Adding Power Steering to Case 646 Loader Tractor

One of my main issues for me, while adding power steering (P/S) to this nearly antique 45 year old tractor, was to keep the modifications, or hacking of the tractor to a minimum. Maybe someday someone will want to restore this antique to its original form and function, which would require removing the power steering. 

Being the first person to do this to a Case 646 tractor, I am essentially building a prototype. If this Power Steering design does not work, I have to be able to return the tractor to a functioning state. 

Therefore, I did not modify the tractor in a way that would prevent me from returning the tractor to normal operations. As it stands I should only need to reinstall the two factory tie rods and re-route the P/S oil supply to drain and the tractor will operate as before.

A discussion on the CCI forum that started back in January of 2017 helped me break the process of adding power steering to the tractor down into 3 areas: Hydraulic Supply, P/S Control Valve, and Hydraulic Cylinder. 

One of the primary issues with adding P/S to a Case 646 or 644 loader tractor, is the need for a separate hydraulic flow for the power steering system. Case - Ingersoll used a couple of different methods over the years in later models to incorporate P/S into those later tractors. 

The Case 648 models started out with the power steering controller in the ‘power beyond’ line that eventually feeds the loader. Which led to the P/S on that model being described as quirky. Because using the P/S impacted the loader speed and using the loader impacted the P/S.

The Ingersoll 60xx and 7020 models use a dual pump arrangement or effectively a separate pump to power the P/S. In the 60xx -7020 models one half of the dual pump drives the PTO, and traction. A second smaller half of the pump drives the power steering and loader (also the backhoe if I recall correctly)

On the Ingersoll 40xx tractors Ingersoll used a hydraulic splitter valve, or more correctly a hydraulic Priority DIVIDER valve. Which is designed to split one hydraulic supply into two different flows, and ensure there is oil flow to the ‘priority’ hydraulic circuit when the rest of the tractor’s hydraulic circuits are idle.

A specialized 'priority divider valve' is needed because when the tractor is setting in neutral there is little if any restrictions to the oil flow, so the oil flows around the system freely and at very low pressure.

If we simply Tee'd off part of that flow for the power steering, the oil, like water in a river, would follow the path of least resistance and bypass the P/S control, which means we won’t get any oil flow or pressure for our power steering circuit.

Therefore we need a “priority divider valve” to create and maintain the separate flow for the P/S. A priority Divider valve has a hydraulic spool valve inside that makes sure the ‘priority’ flow port always gets 1.5 gallons of oil per minute. Regardless of what the pressure is in either side of the system, you always get 1.5 GPM out of the priority port.

Which is good and not so great.. Good in that the P/S circuit ALWAYS gets 1.5 GPM. This means the steering speed and response is always the same no matter whether the engine is at idle or WOT. 

The possible BAD of a priority divider valve is that when the steering hits the limits, the priority valve will still try to push 1.5 GPM to the “priority” port until something blows, or it deadheads the pump and kills the engine. The priority divider will attempt to divert all of the oil to the ‘priority’ circuit in order to get 1.5 GPM to go out that port. 

That’s why there must to be a relief valve in the P/S circuit, the particular valve I used has a relief valve built in. (Prince RD 405R: http://www.princehyd.com/Portals/0/valves/valvesrd400.pdf ) If you use a different valve remember to add a relief valve that is plumbed back to the drain – tank in the P/S circuit somewhere.. 

It's worth noting that the other port on a divider valve is labeled EXCESS flow.. Basically if we don’t need the flow of oil to make the 1.5 GPM for P/S, the remainder of the pump's output is ‘excess’ flow and the divider valve sends the oil out the ‘excess’ port, a better label might be MAIN flow.. . 

The not so great part of a priority valve is that the P/S ALWAYS gets 1.5 GPM before the rest of the tractor gets any oil. You could say that when you are not using the power steering, you’re dumping 1.5 GPM of pump output to the drain.. And you are.. 

When I looked at replacing the hydraulic pump as part of this upgrade I installed a 0.73 Cu In pump. The Case 646, was built with a 0.55 Cu In (8.5 GPM) pump originally.. The new 0.73 pump, at WOT, should move 11.4 GPM, which is a tad much for a “16.5 HP” Onan CCKa to pull. 

But the engine is not producing 11.4 GPM at 2200 – 2400 PSI.. Its producing 9.9 GPM at 2200 – 2400 PSI and 1.5 GPM at 1000 – 1500 PSI which it can handle. 

Which also means I get an increased flow of 9.9 GPM (instead of 8.5 GPM) for the tractor and loader.. (I find it fascinating that the 644 and the 648 models were later updated to use a 9.5 GPM pump, but the 646 was forever shipped with a 8.5 GPM pump)

The new pump I bought bolted right up to the existing mount, and used the same Lovejoy coupler. 

The new pumps output is the same SAE #10 sized port as the old pump. Both the in and out ports are located in the center of the pump’s body instead of towards the rear of the pump like the OEM pump.

The new pump has a standard SAE #12 port for the input – suction line. To get the suction line attached, I used a 45 Degree SAE #12 to 1” hose barb fitting, (# 4603-16-12 ) which is necessary to make the connection to the suction line without putting major kinks in the line. 

The other fun part of the suction line on a Case 646A, is that the space between the engine’s base - oil pan and the frame is SOO tight you cannot run a rubber suction hose through there.. 

I had to re-use the OEM steel suction line to plumb the suction line to the new pump. I had hoped to use rubber suction line for the entire connection like newer models, but it wouldn't fit.

Another issue with the steel suction like is that it had holes in it that were brazed up. The suction line had been rubbing on the steel OEM drain line.. To ensure that the line was not sucking air, I gave all the worn areas a good cleaning and externally applied a layer of JB Weld to seal them up. The new installation would be relocating the drain line so the suction line should not be rubbing on anything.

To create the necessary 2 hydraulic flows or "circuits", I ran the output of the pump first to the divider valve, then the ‘excess’ port of the divider valve connects where the pump's output used to go. (More or less, I added a PTO valve to this tractor at the same time, so the output actually goes from the divider to the PTO valve, then back to the travel valve where the pump used to be connected.)

I installed the divider valve between the tractor frame rails below and behind the engine, basically where the mid lift used to be. I reused 2 of the midlift mounting holes. Which puts the divider valve in front of the steering gear. 

(Which now all said and done a better location might have been on the inside of the right hand frame rail. The placement I used, between the frame rails right behind the engine prevents you from reaching in behind the engine from the left side.. Which makes hooking up the engine wiring a challenge.)

I only needed an 18 inch rubber pressure line to get from the new pump to the input port on the Divider valve. The PITA of this brand – model of valve, IMO, is that ALL of the connections to it are pipe threads (NPT) which means when you tighten the fittings, (even when using a hydraulic thread sealer) you can wind up with the fitting pointing the wrong way. I got spoiled by SAE – O ring fittings where I can align them as I want and then tighten the nut, washer and, O ring to seal it..

I opted for JIC #10 fittings on the divider valve's in and excess – out ports to match the existing tractor fittings, and a JIC # 6 for the P/S – priority flow. The input on the divider is on the top (as I have it mounted) and the outputs, both P/S – priority flow, and main (or excess) flow are on the other side – bottom. 

http://www.princehyd.com/Portals/0/valves/valvesrd400.pdf

Another challenge of splitting the oil supply is that you need to connect the output or drain from the P/S controller AND the output of the pressure relief valve, both back to the tank. I guess one could go redneck and run the drains back to the filler cap….But, we're not..

With a new pump and new P/S system on the tractor, I really wanted a hydraulic oil filter in the system, and for that to be effective the filter needs to be in the return – drain line. It needs to filter ALL of the oil that is returned to the tank.. Therefore the return from the P/S circuit needs to be plumbed into the drain BEFORE the filter.

This was a challenging part of the system to design and implement. By having a ~ 12 GPM pump I needed a filter that could handle that flow, which based on price and availability, it rounds up to a 25 GPM filter.

Which is a physically large filter, not super huge, but real-estate on a Case 646A in the drain line area is at a premium. AND, there are these pesky front tires that take up a lot of the space where I thought I could put the filter.

The ‘drain line’ starting at the P/S controller is a JIC # 6, and the priority valve’s built in relief is a 3/8 NTP.  I combined the output from the P/S controller in with the pressure relief output and routed both back to the main drain – return line. Which is where the fun started.

The standard drain setup on a 646a is a 5/8 ID steel line from the travel valve and a 5/8 steel line from the loader valve that both arrive at a JIC #12 TEE fitting located on the right side of the 'engine compartment' below the loader valve, behind the engine (again). The 3rd leg of the tee normally connects to an additional 5/8 steel line that routes around the side of the engine and ends near the oil cooler in the front of the tractor.

The JIC # 12 Tee (#15 on the Diagram) seemed the best place to route the P/S drain back into the system before the hydraulic filter. I was determined to not modify – hack the OEM return line (#16), but instead replace that section of line from the JIC # 12 Tee to the cooler with the filter and something else..

The space between the CCKa’s oil pan foot and the frame rail where the drain TEE is at is VERY tight, so much so that only a 5/8 Steel line could make its way out of there. My ¾ ID rubber return hose was not going to fit, nor would it make the bends needed.

Between the motor mounts, plus where the front wheel sits during a right turn and the size of the filter, the only practical place to locate the filter is right under the engine’s oil drain plug. Butted up against the frame. The only way to connect to the filter in that location is come THROUGH the frame:

Therefore, I had to hack my tractor. 🤷 There is now a 1 ¼ inch hole in the plate on front of the right side ‘loader tower’, similar to where – how the steering tie rod comes through the frame on the left side of the tractor. A carbon steel hole saw can and will make the hole. It takes time and lots of cutting oil, but it can be done. 

I wound up ‘turning’ the JIC # 12 TEE connector so that the ‘open’ end that used to route to the oil cooler, is now pointing down instead of forward. Because the hydraulic filter is ¾ NPT, (did I happen to say I HATE NPT fitting in a hydraulic system?) 

I was able to source a JIC # 12 Female to ¾ NPT 90 degree elbow (# 6501-12-12) which when attached to the JIC # 12 Tee put the ¾ pipe in a good position to attach the filter head. I added a ¾ NPT TEE to the 6501-12-12 fitting so I could connect the drain from the P/S circuit. Next a 4” long pipe nipple runs through the hole I cut in the frame to the filter head.

The assembly OUTSIDE the tractor looks like this:

This can only be assembled in place, and I had to screw the filter head on to the pipe nipple before I connected the JIC #12 fitting to the drain Tee fitting in order to get this in place. Needless to say, it's a tight fit. 

The output of the P/S controller, is routed to a JIC # 6 to NPT fitting at the priority valve, then combined with the relief valve output, that runs through a 3/8” ID JIC # 6 hose and terminates at the ¾” NPT TEE in the drain line.. 

The last connection from the hydraulic filter output to the OEM oil cooler is done with ¾ ID rubber drain line and hose barbs. To reduce the number of bends in the Rubber drain hose, I added another 4” long 3/4” pipe to the filter output, then a 45 Degree elbow puts the hose barb in about the best (not ideal) location to connect to the oil cooler. My only fear is that rubber hose might collapse or kink when hot. But it's where I can keep an eye on it. So we shall see.

Power Steering Controller

There are probably more P/S steering controllers types that this, but for this project I looked at ‘rotary – pump’ steering controllers, (which is what all of the OEM Case and Ingersoll tractors used),  and an inline ‘power assist’ spool valve.

The rotary pump controls are a very nice solution.. You just have to find space to put them (usually under the dash) and connect them to the steering wheel. 

When Case added a rotary type steering control to the 648 model they had to relocate the other controls on the dash outward to make room for the P/S unit under the dash. Since I was not going to redesign the entire dash, and I could not conceive of some way of squeezing that type of controller under the dash, I looked at the second type of P/S controller – an inline spool valve.

A ‘power assist’ inline spool valve seemed to require the least amount of hacking to the tractor. There was a series of ‘garden tractors’ that used these in the past, the JD 400 series tractor . This type of P/S controller seemed to be a minimally invasive upgrade, it replaces part of the tie rod from the steering sector gear to the spindle arm.

This type of controller is basically a hydraulic spool valve that fits in the steering tie rod. When you turn the steering wheel, you move the spool valve out of center and it routes oil to a hydraulic cylinder that ‘assists’ in turning the wheels. Once the cylinder moves the wheels enough to null out your movement the oil flow to the cylinder stops. Pretty simple ‘servo’ system.

One of the challenges of adding this particular P/S controller to the Case 646a is that the P/S controller uses ½ inch fine thread tie rods vs the 646’s use of 5/8 fine thread for the tie rods.

Where to physically locate the P/S controller to work around the front axle, the front tire, and the motor mount was interesting.

After a bunch of mock ups, and rebuilding my steering sector gear and lowering where the tie rod attaches to the sector gear, I was able to get the controller into a workable position.. In addition to lowering the rear of the tie rod, I also had to space the Heim end at the spindle arm down as well so that the body of the P/S control just clears the axle. One of the major constraints on the 646, is the front motor mount. When the steering is turned to the right, and the front axle articulates up on the left side, where the controller is located, the P/S controller will impact the motor mount and can flex the tie rods.

To adapt from the 5/8 tie rod size to the ½ inch size, I used a ½ inch Female, right hand threaded Heim end at the wheel spindle with a ½ inch bolt and a spacer to center the bolt in the 5/8 hole of the spindle arm. 

I made a custom 5/8’s rod that is threaded 5/8 LEFT hand on the end attached to the sector gear and turned down and threaded ½ RIGHT hand – fine at the other end for the P/S controller. I opted for the left and right hand threads so I can adjust the length of the rod to center the steering wheel, or make other adjustments.

In order to make the 5/8 LEFT hand threads, I ordered a threading die for around $25 and threaded the rod with the die.. I also had to make new tie rods for between the front wheels which also have left hand threads on one end of them..

Once the P/S controller is in place I ran a JIC # 6 hose from the divider valve’s, priority port to the IN port on the P/S control. The Out of the P/S gets Tee'd in with the pressure relief output of the divider valve pressure relief, before being plumbed back to the main drain – return line.

After that, I ran 2 - JIC #4 hoses to the P/S cylinder.. Depending on your setup, the lines may connect different from mine.. One good thing to remember is that with the tractor's front end jacked up, you can connect an air line to the P/S controller and verify that the lines are connected correctly. If you turn the steering wheel and the hydraulic cylinder kicks back at you, the lines are wrong :-) 

Using an air line and manually operating the steering lets you check for binding or areas that need changes for clearance.

Locating and Mounting the Hydraulic Cylinder

Or, may the fabrication begin..

All of that new found hydraulic power and control doesn’t do much good, if you can’t use it to turn the wheels. Which is accomplished in most P/S systems with a hydraulic cylinder.. Usually something about 2 inch bore and 6 inch stroke, for Case 646 sized tractors is used, although not all of that 6 inch stroke is needed.

I had a couple of personal criteria for mounting the hydraulic cylinder.. 

1. I did not want to run it from the tractor frame to the axle like the OEM setup, because the cylinder is generating around 4,710 pounds of force at 1500 PSI. I had images of the cylinder ripping the front axle off.

2. The type of P/S controller I picked must be installed in the tie rod from the sector gear in order to function, so you can’t replace the tie rod with the cylinder .

3. The spindle on the opposite, right, side of the tractor is not long enough to put an arm on the top of it.. 

4. I didn't want to reduce the ground clearance of the tractor by hanging the cylinder under the frame or axle.

(When Case added P/S to the 648 model, they changed the attachment of the steering arm to the top of the left spindle.  On the manual steering models the connection is a single 1/4 inch wide woodruff key. The P/S models all use a multiple splined shaft and arm instead. My take on the change is that Case  wanted or needed a stronger joint because they now had a hydraulic cylinder pushing on that arm..)

Because this is a LOADER Case moved the steering tie rods to behind the axle to safeguard them (as compared to the Garden tractors where the tie rods are in front of the axle). 

I was not crazy about putting the cylinder out in front of the tractor.. If I did the cylinder would need some kind of protection, even if only a covering on the rod so dust and dirt is not being sucked back into the system. I had considered adding a ‘bumper’ in front of the cylinder, but just did not like the idea.

While I was working on the P/S design I picked up a 2 x 4 tie rod hydraulic cylinder that has a 5/8 rod and was already threaded ½ fine on the end of the rod. Unfortunately, or fortunately, the cylinder does not have clevis mounts on either end.. When I received it, it was setup to be bolted down via a plate on the rod end.

When I studied how far the tie rods on the Case 646 move when steering I found that the travel was about 3 1/8 inches (I have 5/8 Heim ends on the tie rods instead of ball joints, which may limit it a bit) Hmm, I have a cylinder that wants to travel 4 inches and I need to move the tie rod a maximum of 3 1/8 inches, sounds like a job for a lever.. 

In my mind because my 2 inch bore cylinder produces over 2 tons of force, I wanted the cylinder to hit its end of stroke instead of the steering hitting its limits or some kind of stops I fabricated. I figured that the cylinder was better able to handle hitting its limits than the steering system, which was never designed for P/S in the first place.

Coupling the desire to keep the cylinder off the front of the tractor and the need for a lever to reduce 4 inches of travel to 3 1/8 inches, I started looking at mounting the cylinder between the frame rails under the engine. My tractor does not have the front belt clutch and I don’t know if I’d ever use it, Also previously I had removed the mid lift cylinder and mounts. So I had a fairly clear space to work with.

But, the need for the 4 inch to 3 1/8 inch conversion in the movement just made things really complicated.. As part of attempting to design this, I realized that I could fit the cylinder I bought vertically under the hydraulic reserve tank in front of the engine and more directly connect it to the steering tie rods that are located right below that area.

To eliminate the 4 inch to 3 1/8 inch conversion, I started looking for a cylinder with a 3 inch stroke instead of the 4 inch I had. During my research I stumbled upon a surplus cylinder with the comment;” the stroke could be increased if the internal stop was removed” ??? 

Hmm, So I can shorten the stroke of the cylinder without any heavy machining? Just add a block, or in my case a piece of a 5/8 ID brass bushing, to the cylinder rod? Cool, so now I have a cylinder that fits under the hydraulic tank, and it moves only 3 1/8 inches.  All I need is a 1:1 lever to convert the cylinder's vertical motion to horizontal and connect to the tie rods.

Locating the cylinder and lever mechanism in the front of the engine under the hydraulic tank, where the clutch would have been, means I can connect the hydraulic cylinder’s action into the tie rod between the front wheels. Which keeps the steering force inline with the axle.

I designed a lever that transforms the vertical movement of the cylinder to a horizontal movement connected to the steering tie rods in the center of the tractor. The fun part was sizing the lever mechanism so that it was as large as possible, but it also did not hit the frame.

The design lent itself to attaching the hydraulic cylinder at the rod end and letting it move back and forth as needed under the tank. (which later turned into some REAL fun..)

I sketched out the lever design and necessary pivot points on graph paper and transferred the critical points to 1/4” thick plate steel. Once the plates were cut out, I match drilled both plates and tapped holes as needed.

I have a supply of 5/8” id by 1” OD Brass bushings that are 2” long that worked out perfectly for this.. The lower pivot point has 2 – 5/8” Heim rod ends stacked side by side, which makes for 1 1/2”, add 2 layers of ¼ steel plate and you have a 2” wide assembly for the “lever” arms.

I ran 2 pieces of ¼” thickness 1 1/2” angle iron across the frame as the main supports for this and added ¼” plate hanging down below the angle irons for the central pivot to attach to. This assembly sits on top of the two hydraulic tank support brackets. Which added more fun, the front edge of the angle iron cross piece landed in the center of the bolt hole for the tank support bracket. I added a scrap of ¼” thick iron to the front of the angle iron so the bolt sits on a level surface.

Locating the cylinder & lever assembly in the center of the frame meant that I had to create new 2 piece tie rods between the front wheels. The OEM tie rod measured 20 inch from hole center to center. Once I factored in rods with Heim rod ends on both ends I came up with needing 2 – 5/8” rods that were 7 ¼” – 7 ½” long.. I threaded each rod right hand on one end and left hand on the other end so I can adjust the rod lengths for toe-in, and centering.

One problem I ran into was binding of the Rod ends at the wheels. I had used standard hex headed 5/8 bolts, nuts and lock washers to attach the Heim ends to the spindles.. 

The new center pivot on the tie rods, causes the rods to angle up in the center about ½ inch when at the limits of the steering.. The large 5/8 bolt heads and the nuts I had under the Heim ends caused the rod ends to bind before they got to the steering limits. 

When I was figuring out where to locate the P/S controller, the head of the bolt on the left hand Heim end was really close to the hydraulic lines and I thought I should replace that with something thinner, like a Carriage bolt. Well, now with the Heim ends binding, I needed to modify the attachment of the Heim ends at the spindles to allow more movement.

I had seen special ‘Heim End Cone Spacers’ that are turned down so that they don’t interfere with the ball on the Heim end. Being that I have a metal lathe, I used some 5/8 carriage bolts and turned the heads down, removed the squared section and then cut some “1/2 inch” water pipe to make spacers and bolted it back together.. Now the Heim ends clear the bolts and spacer so I can turn the steering completely from left to right.

One area that I did NOT prototype well enough and pay attention to is how much the top end of the cylinder rocks as it cycles through the arc of the lever.

When I first attempted to reassemble the tractor and I installed the reserve tank supports I found that when I turned the wheels the top of the cylinder tipped so far over that it hit the left hand support (the one on the muffler side) and I could not turn the wheels all the way.

Back to the graph paper to see how I can modify the design. I had to move the pivot point of the cylinder mount over 3/8” so the cylinder's pivot point is more in the center of the lever’s arc, which changed how far the lever moved the tie rods left and right when turning the wheels. I fixed the cylinder hitting the mount, but I still could not turn lock to lock.

Next I worked out where the attachment point for the tie rods had to be moved  in order to correct the movement. Which involved welding closed the existing holes, adding onto the one edge of the lever and drilling and tapping a new attachment point on the lever.

I also had to cut a notch - relief in the one side of the lever so the Rod end at the front center didn't bind:

I can report that the P/S system works and works quite well. I can turn the steering with a full load on the loader with minimal effort.  The system might benefit from a little more hydraulic flow, like 2 GPM instead of 1 1/2, but swapping out that $$$ divider valve is not on my todo list anytime soon.

Overall the tractor has plenty of speed, and strength. It will lift more now than with the old hydraulic pump.. 

Alternatives to this design & lessons Learned:

Now that I’ve constructed all of this mechanism to connect the vertically mounted cylinder to the tie rods, and made custom tie rods, I am seriously reconsidering the decision to NOT put the hydraulic cylinder on the front of the tractor. 

I’ve got 75 to 100 hours into building and debugging the setup. Building this a second time should go faster, but the lever mechanism, tie rods and rod ends are complicated to construct and assemble. Installing the cylinder as I did under the reserve tank also means that I have to dissemble a lot of the tractor if that cylinder needs to be serviced. And of course I have no Belt PTO on the tractor and can not have one. There is about 3/4 of an inch space between the side of the cylinder and the head of the flywheel bolt. 

One of the things that additionally held me back from putting the cylinder in front of the tractor was the fact that my 2 x 4 cylinder just fit in between the brackets that are welded to the front of the frame, with no space left to attach the cylinder to the frame or to the axle.

A 2x4 hydraulic cylinder’s body will pretty much fit in between the frame right in front of the pivot pin. If we reduced the barrel length of the cylinder so the travel is limited to 3 1/8 inches, that cylinder would fit with room to attach one end to the frame or better yet attach it to the axle. 

Cutting the barrel down leaves you with a longer rod, which helps. Because, you’re going to need to extend the rod far enough to connect the cylinder to one of the spindles.

To connect the hydraulic cylinder's rod to the steering with a minimal of hacking, I would extend the bracket that the Tie rods connect to on the back side of the spindle out in front of the axle on one side. This would provide an attachment point for the cylinder. 

I think it is possible to place a 3/8 x 2 flat iron parallel to the existing tie rod bracket and extend the arm from the back of the axle out in front with no welding or modifications to the tractor. If we run our new flat iron along side of the factory tie rod bracket, on the inside of it, the new piece can run under the axle and come out in front of the tractor.

To not hack the tractor and weld things on, if our new piece of iron has a tab welded onto the bottom at 90 degrees, so that it runs under the tie rod bracket, we can drill a hole in that added tab and use the rod end’s bolt to hold things together at that end. Moving forward, to where we pass the axle, we should be able to run a ‘U Bolt’ under our new bracket and around the axle and use that to hold and clamp our piece securely to the factory bracket. If our new bracket is the same length in front as behind the axle the movement of the free end of it should be 3 1/8”. The same distance the tie rods move.

I have not prototyped exactly how the cylinders rod needs to be extended and attached to this new bracket, but the cylinder’s rod is going to need a dust cover. Why not give the cylinder a real cover? 

Standard thickness “3/4” water pipe (Schedule 40) will fit inside standard 1 inch water pipe, if you file out the weld on the inside. One piece of ¾ pipe combined, or running inside 1 piece of 1” water pipe should make a nice telescoping cover for the cylinder's rod, and would make a fairly tough guard for the rod. 

With a loader there is always the problem of dumping a log, or stump or rock on to a pile with the loader, and having that rock, etc roll back down the pile right in to the front of the tractor.. If that rock is large enough and hits the P/S cylinder or the rod in the right spot, that's the end of your power steering. Therefore protecting that cylinder and rod are very important. That's part of the reason why I opted to put the cylinder inside the tractor. 

Hopefully my experience can inspire others and hopefully reduce how much time someone would spend fabricating this the next time. 

What have I left out of the description of this build? There is a more complete photo album on google, each photo should have comments that I added describing what each photo is: https://photos.app.goo.gl/1fbGxQfyTfoFVLku8

You may need to click on the info icon (a circle with an 'i' in it) to be able to read the entire comment I added to the photo.

Bandsaw Lumber Mill - Simple Saw - Bill Rake pattern

Building a Sawmill based off the Bill Rake ‘Simple Saw design’.                         March – April 2014…

Video of our Version of the Simple Saw in use: Sawing Red oak 

My son asked me if we, ala I, could build a sawmill because he had access to lots of standing timber and he saw it as a good hobby. He initially purchased some plans from the internet for a chainsaw based system. But in looking over the plans, the cost for the long – long chainsaw bar, plus a very large chainsaw engine, plus special ‘ripping’ chains kind of put the cost of doing that out of reach.

I recalled seeing something about DIY bandsaw based sawmills. After some research I found several free copies of plans, that are not of really high quality, but they were enough to get me started, since I NEVER follow anyone’s plans exactly anyway.

Plans Version1   Plans Version 2  Plans Version 3

Photos of other peoples builds for more ideas: http://kruppt.tripod.com/mill_1/

The basic parts of the Bandsaw mill are a lawnmower engine, I used a vertical shaft 12 HP Briggs since I already had it, 2 – 12 inch ‘boat trailer’ wheels on rims. Trailer hubs, shafts, belts and pulleys to drive everything. Angle Iron for a track that in our case is sitting on top of a shortened Mobile Home trailer frame. And Box tube for the uprights and cross pieces.

2 major departures from the ‘Simple Saw’ design we made right off were to use a vertical shaft (riding) mower engine with a twisted belt to a jack shaft instead of the more expensive Horizontal shaft engine.

We used all-thread rods to raise and lower the ‘mill head’ instead of a boat winch and cables.. I felt the blade and mill head might ride up when it runs into a knot in the wood. Using 5/8 – 11 all thread rod to raise and lower the mill head meant that 10 turns on the rod (crank handle) would move the head .9 inches which is not a bad rough dimension to make ¾ -.75 finished stock out of. That dimension gives us enough allowance for shrinkage when drying and then planing the wood.

If you watched the video, you can see the 'power lift' option on the design.. Nothing fancy, just a Dewalt 18 volt cordless drill chucked to a turned down section of the all thread. We wanted a battery operated lift option and who does not have an old cordless drill in the shop? (If you don't have a lathe to turn the all thread down, put double - locking nuts on the shaft, and put a socket in the drill..)

Several things that make this saw build work are the fact that “12 inch” trailer tires are just about the right size for this kind of bandsaw and they cushion and drive the blade without any problems.

Second is that ¼ inch thick 3 x 3 steel box tube will fit OVER 2 ½ x 2 ½ box tube almost perfectly and that’s how the ‘sliding' joint of the mill head is created. You will probably have to hand file the welded seam off the inside of that 3 x 3 box tube, but the pieces are only about a foot long.. 

Other items we used that are different from the online plans, is we used an entire ‘riding mower’ frame as the deck where the engine is mounted along with the 'jack shaft' and pulleys. This also gave us room for a gas tank, blade lube tank, etc.

The steel for the tracks and most of the mill head frame was purchased as new steel. We did substitute and use existing used steel from around the shop for other parts of the mill.

I have 2 metal lathes, a milling machine and several arc welders in my shop, therefore some of the steps or choices I made in design and construction may not work unless you can machine your own parts.. 

While I worked on the 'mill head' my son worked on the track - deck - trailer.. We picked up a stripped Mobile home trailer frame for cheap, these things are really fun. The frame as it sat exceeded the legal size you can tow down the highways in Illinois.. So, first we cut the outriggers off and then we chopped the frame in half lengthwise (there were welded joints at that point already).  Then we were able to load that onto our car hauler trailer to bring it home.. The son converted the 40+ foot long trailer frame in to the 20 foot long Sawmill frame by relocating the axles and suspension. He also installed all of the cross sections from the discarded part of the trailer frame into the 20 foot 'new frame' to make is stronger and give us places to mount log dogs, etc. (This could be street legal if we added lights, etc..):

                                 Before:                                                                            After:

If you watched the video you might notice that the mill head and log are setting off to the one side of the trailer and he is walking on a platform on the other 1/2 of the trailer.  We recycled old deck boards to make the work area on the trailer frame to make operations much easier.  The trailer - sawmill is semi permanently installed at our farm now with a 'log deck' built next to it..

 The mill head simply sets and rolls on the edge of 2 - 20 foot long 2 x 2 angle irons. Which means the mill head is not held down. On the one hand we can lift the head off the trailer and store it inside.. BUT, if you FUBAR you can flip the entire mill head OFF the trailer!

The Bandsaw portion of the Sawmill consists of an inverted U shaped frame that rolls on the angle iron rails of the trailer or base. The inverted U comes down on to Channel iron 'feet' that are supported on 4 'V' rollers Example of V Rollers .. Adding small tabs to the bottom on the U channel made nice axle mounts.  If you locate rollers that already have mounting plates, an option is to flip the U-channel over and bolt the caster mounts to it.. Another detail to watch is that you will NEVER be able to lower the blade below those U-channel feet, so the taller they are off the track the taller your log needs to set and the more complicated the log dog design becomes..

The entire sawmill assembled looks like this:

Starting on the left is a vertical shaft 17 HP Briggs 'lawn mower' engine. We started with a 12 HP, but "Tim Allen" needed more power.. AKA to be able to cut faster..

3/4 of the way to the right is the HORIZONTAL jack shaft that the engine drives.  The key points to use when engineering a twisted belt is that the pulleys must be aligned in their centers.  The center of the pulley on the jack shaft must align with the center of the engine crankshaft in the vertical plane. and the jack shaft center needs to align with the center of the pulley on the engine in the horizontal plane.

Then on the far right is the final drive pulley, shaft and drive wheel - tire..

Underneath and closer it looks like:

That's pretty much the belt setup. We recycled the lawn mowers engine mount with the slotted holes and that's how we adjust the tension of the 1st belt.  The engine has a centrifugal clutch on it, so the band engages when you throttle up and disengages at idle.

The jack shaft is a 3/4 shaft that is riding on standard pillow block bearings.. Because I have a milling machine I cut keyways as needed to attach and drive the pulleys..  Pre keyed shafting is available if you need to go that way

The final drive belt tension is handled by a spring loaded idler.. We needed some kind of fail safe in here somewhere.. If we jam something up, the final drive belt can slip.

I created a blade speed calculator so we could see what different clutches and pulley ratios would do to the final drive speed, you can access that at: Blade Speed Calculator

Our bandsaw blade supplier Timberwolf blades specifies that 5,800 Surface Feet Per Minute is the max speed for these blades. (that should scare or instill some level of respect for the machine in all of us, at that speed the band is doing 65 MPH!!! When the blade snaps what happens to you and the mill head depends on your design (skills) !!)

Next let's 'walk around' and take a look at the tension - idler side of the mill.  The non-driven wheel needs to handle blade tension, plus blade tracking. Think of a standard 'Rockwell Delta' bandsaw.  The driving wheel in a standard bandsaw is on the bottom and it's NOT adjustable. The upper wheel is used to adjust tension and tracking.. This side of the sawmill functions the same as the UPPER wheel in a typical bandsaw. And the theory behind adjusting and aligning the wheels, and blade guides in this bandsaw is no different from its cousin..)

My design for this is TOTALLY different from the 'simple saw' design.  The simple saw design has the 1 inch trailer shaft butt welded to a thick plate like this:

There are probably LOTS of saws out there that are built this way and working.. I guess I don't trust my welding skills.  Plus I had these scrap shafts that I machined the 1 inch trailer axle onto the end of.  So, why cut the shaft off, when I can use the entire length of the shaft for greater strength? 

Also you need both tires to run in the same plane. Once the wheels were mounted I put a long straight edge on the rims and moved the axles in and out until the wheels were in alignment..

Since I have a long shaft, I can accomplish tracking adjustments by moving one end of the shaft while the other end is stationary. That's what the chain in the center of the picture does. Normally it turns both threaded rods at the same time to adjust the blade tension.

By loosening the thumb screw behind the conduit 'handle' on the right, we can keep the rear threaded rod stationary while the chain turns only the front screw to adjust the tracking.  There is a flat plate attached to the front of the mill head that the front threaded rod moves and the rear alignment is handled by a scrap of the same 2 1/2 x 2 1/2 box tube running inside a scrap of the 3x3 box tube. Most likely overbuilt to the max, but that's how we tend to fly around here..

You can also see the 5/8 all thread that runs vertically to raise and lower the mill head. We used a coupling nut so we had more threads to bear the load.  Trying to align multiple nuts and weld them in place will NOT work, the heat will make them move just enough that they will bind. You can get all thread in lengths up to 6 foot long cheaply..

The wheel hub on this end (the idler) is 100% standard trailer hub, tapered roller 'wheel' bearings, rear seal, grease cover, etc.

Continuing to walk around, here is the front of the mill head:

Still looking at the idler side. you can see how the mill head frame needs to resist the tension of the blade.  The Simple Saw design runs a box tube right inline with the wheel axles.  Which directly opposes the force that the blade tension puts on the entire mill head. And if you know how much tension it takes to keep a 1/2 wide band on that Rockwell Delta saw tight and running true, you can guess how much tension it takes to keep a blade 3 times that wide at 1 1/2 inches tight and running true..

I wanted to give the saw a larger throat, for a thicker cutting capability. Therefore,we moved the cross piece to the top of the mill head and added 45 degree braces. Have we ever used the full cutting depth of this saw ?? NO (not yet) , but it certainly gives a nice clear view of where the blade is and what its doing..

The blade guides on both sides of the saw are the same and they are a set of ball bearings,

The 'hold down' bearings are some odd ball 2 inch long bearings premounted on stub shafts that I found at Surplus Center, and they no long have them.. Many people just put double or triple bearings on a common shaft.  

The "backup bearing" is a standard flat race bearing from a lawn mower hub if I recall. I made cams -  offset shafts by turning a 3/4 shaft that fits the bearing ID, down to 5/8, which is what runs up through that box tubing. If you loosen the top 5/8 nut you can rotate the shaft and adjust how close the bearing is to the back of the blade. The shafts look like this:

Cams like these are NOT that hard to make on a lathe. You just add a spacer between one of the three jaws of the chuck equal to the offset you want and tighten it up and turn the shaft to size..

The 'blade guides' on the idler side of the mill head can be adjusted in and out to widen or narrow the cutting throat, and they can also be adjusted up and down. The driven side guides can only be adjusted up and down. Those adjustments let you square the blade to the saw's travel and also allows you to 'lift' the blade off the tires as it cuts to keep the blade more stable.

Walking around some more we get to the drive side of the mill:

We used (re used) an 1 1/4 inch shaft on standard 'pillow block' ball bearings with a 10 inch pulley on the end as a final - main drive shaft, the shaft used to be in a JI Case combine.. 

The end that drives the wheel has 2 sprocket hubs on it that were turned down on the lathe to fit inside the wheel hub.  We drilled and tapped holes from the outside of the wheel's hub into the 'sprocket' hubs and bolted it all together.. 

I was really concerned that welding the cast iron trailer hub would cause things to crack, so we bolted it together instead. 

There is some adjustment possible in the pillow block bearings as well as the shaft that the idler rides on so you can make sure the tires are running plumb, straight, level, etc.

Also once you get this all assembled and working, without a band on the tires, grind - sand down the drive wheel to take the bulges out of it and also to form more of a crown on the tire. With the engine running, put a sanding disc on an angle grinder and go to it.. (A dust mask and goggles MIGHT be handy, just saying.. :-) You should be able to hold the grinder steady enough by hand to accomplish the job.

Then swap tires, put the idler wheel on the driven side of the mill head and do the same process to it.. (your idler hub had better run fairly true, if not you've got other issues you need to attend to.

Each one of these saws and saw builds is unique, Hopefully that explains the choices we made and gives you some ideas to work from.

3 Phase Power in the Home Shop

I assume most people are like me and when someone talked about running 3 phase powered tools in my home workshop, I said there was no way to do it. In 'the states' 3 phase 220 volt power is not automatically wired to everyone's home. I live on the END of the line in a rural area where the 'high line' is not even 3 phase. The possibility of getting 3 phase power at my house are essentially ZERO.

When I found an absolute STEAL on a milling machine, I bought it..... BUT, the mill has a 1-1/2 HP 3 phase motor on it. Initially I had planned to purchase a NEW single phase motor to replace it.

That was until some of the discussions on the internet explained what a Variable Frequency Drive, VFD, or Motor Drive was.  A few searches showed that I can purchase a VFD with MORE capacity that I needed, for only SLIGHTLY more than the replacement motor would have cost me.. COOL..

AND, the VFD would provide: Soft Start of the motor/mill, electronic Variable speed, Electronic OVER speed of the motor, Nearly instant braking of the motor and mill, and 3 - phase power for OTHER devices in my workshop.

The one thing that complicates the setup of 3 phase equipment with a VFD's is that VFD's  are NOT well understood by home hobbyist, and the manuals provided are well...... translated from Chinese if that says enough.

In this blog post I want to document my experience in setting up a VFD. Which is actually VERY easy to do. Once you get past the lousy documentation..

I settled on the Teco FM-50 model 202 which is 220 volt single phase input and 220 volt 3 phase output VFD. It is rated to drive up to a 2 HP motor or, more accurately capable of up to 7 amps of output.. I am planning to drive a 1-1/2 HP 3 – Phase motor on my RF-30 Mill Drill with this unit initially.

The AC hookup was very straight forward. Points to note are that the 3 phase output of the VFD MUST be wired directly to the motor (no switches or fuses in the lines).

My AC input for this is a 20 amp 220 volt circuit that I use for my Lathe and Mig Welder (I have a 220 - 20 amp plug on the wall in my shop.).  There is NO Neutral in that connection, so the wiring on the VFD INPUT side goes to L1, L2 and then of course the Ground Tab.

The cord I located to run from the VFD OUTPUT to the RF30 mill's motor only has 3 wires in it, so I ran a separate 14 gauge ground wire to the motor. I also ran that same ground wire to the Mill itself to ensure it was grounded as well.. I attached the wire to the head so that everything is grounded.

My 3-phase motor ran 'backwards' (as is often the case) when I first setup the wiring.  But changing directions on a 3 phase motor is as simple as swapping 2 of the 3-phase wires at the motor, which corrects that problem.  I powered everything off, and swapped the first and second wires around at the motor to correct the direction of rotation problem

One thing to note is that, when I unplug the VFD, its takes almost 30 second for the display to go off. So I am careful to wait until it is TOTALLY off – dead – (blank display) before I touch the power wiring.

If you don't want or need a "remote control" panel for the VFD and are OK using the start - stop buttons on the front of the unit, that's about all you need to do for the setup. There are some programming or settings changes you might want to make even without “remote controls” to tailor the VFD's operations to your liking. But I started working with and running the VFD and mill with ONLY the power connections and controlling the start/stop and speed of the motor right from the VFD front panel.

To ensure that everything was setup from the factory correctly one of the first things I did programming wise to the VFD, was to force a "factory reset" by setting function 25 to 020 (for 60 Hertz power). Many comments on the net indicated that people sometimes had weird symptoms or operation issues with the VFD until they reset it to factory defaults. I figured it would be best to just start there.

Setting up remote controls for forward – reverse and variable speed can be done with a single switch and a single Potentiometer (often referred to as a 'Pot').  I got my parts from Radio Shack. A Single Pole – Double Throw – Center off switch (SPDT), part number 275-711 was $3.50, I think it was described as a replacement automotive switch. There's no need for heavy duty or anything like that. The switch was cheap and the longer handle – paddle on it seemed to me like it would work well in the shop. I also picked up a part number 271-1715 10k Ohm Linear taper Pot (also $3.50).

There are two possible 'tapers' in Pots. One is called audio taper and the other is Linear.  As the name linear implies this type of pot has a straight line increase in resistance as you turn the knob.  An audio taper is more like an exponential curve and the increase in resistance is NOT a straight line. IMO the straight line change in speed is what we want for machine operations.

All of this, the switch and Pot, can be housed in a wall outlet type junction box and it only needs 6 low voltage wires to connect it.  For my junction box I choose an old metal one I had lying around because I could stick a magnet on it and then just 'stick' the “control panel” to the mill's head.  I used a blank metal cover plate that I drilled out to accept the switch and Pot's shanks. (and you could just as easily use some heavy sheet metal for the cover or the entire box for that matter if you have a bending brake. A plastic cover might not hold up well with the toggle switch snapping back and forth in it..)

I had a nice length of hookup wire (which actually has about 12 wires in it instead of 6) that I used to make the hook up.  You can use telephone wire, 'intercom' wire or network cabling. Anything that could be used for low voltage connections. Stranded wire would be more flexible, but the cable I dug up for example is solid wire.

One word of warning on Network cable, it generally has 8 wires in it.. BUT those are configured as “4 pairs” and the color standard in the cable, is Blue – White, Green – White, Orange – White and Brown – White. Depending on the cable vendor or supplier, those 4 white wires may NOT be color coded. They may only be twisted or wrapped with their “paired” wire, the Blue, Green, Orange, or Brown.  You might find that you can not tell which of the 4 'white' wires is which in that type of cable.  Before you decide to buy or use networking cable it would be advantageous if you can check the end of the cable, or cut into the jacket so you can see how the wires are color coded.

The ideal version of Network cable to use has each of the white wires marked with a colored stripe. One white wire would have a blue stripe, one has green, orange, etc. That way you can keep the wires straight as you're wiring things up.  For a basic setup you only need 6 wires, and a network cable usually has 8. Whether the wire is “twisted pair” type wire or not should not matter in this case.

One of the things for me that made this setup VERY confusing were the MANUALS.  The versions of the Teco FM-50 VFD manual I downloaded off the net were OLD and do not include some of the diagrams and details that the pocket sized manual that came in the box has. The first additional page or diagram in the pocket manual that I though was useful is a block diagram of the power wiring:

This makes it pretty clear where any breakers, or switches or contactors, etc are to be located in the AC power lines.  It also makes it clear that there should be NOTHING between the VFD and the motor.
Apparently the reason for that is because the VFD electronics are constantly monitoring the motor and IF the motor is disconnected the VFD will continue to attempt to drive the motor, even though its disconnected and that can FRY the VFD..

In my case I do plan to eventually share the VFD between the Mill and the Metal lathe. BUT, there will be a AC disconnect installed BEFORE the VFD so I can power it completely off.  Right now it has a line cord to a 220 – 20 amp wall plug that I use to power it off..

 I plan to eventually be able to switch the motor connections with a pair of L14-20 twist lock plugs on the VFD output. To do that it will be necessary to power the VFD COMPLETELY off, unplug one motor, plug in the other motor and then power the VFD back on. That's part of why my “Control panel” is 'mobile'.

I was really confused by the descriptions of the 'multi-function' inputs in the manuals.  I could see the multi-function outputs described in the pin out diagram. BUT, the way the diagrams look to me, all of the Input lines are labeled as having a single function.. The diagrams as presented lead me to believe that Pin 6 is SP1 and Pin 7 is Reset, Correct?  Well actually NO. Pins 6 and 7 can each be assigned anyone of 6 DIFFERENT functions. Pins 6 & 7 ARE the multifunction INPUTS...

Also pins 3 and 4 can either be setup as: ON/Off for Forward and ON/Off for Reverse OR Pin 4 equals Direction and Pin 3 is Start/Stop. For our use and simplicity in setting this up,  the 1st option, 3 = Fwd and 4 = Rev is the simplest setup.

Another page that is missing from the Online and OLDER manuals is the options, or programming chart. This charts lists ALL of the options for all of the 'functions' in ONE PLACE. Notice the 4th column for Functions 19 & 20 as an example.

The chart also makes it clear that the multi-function OUTPUT can be set to 3 different outputs. The multi-function OUTPUT (pin 1 and 2) can be; On when the VFD has power, or ON when the motor is up to Speed, or ON when the VFD has a fault.

Let's get back to the wiring and setup for a plain and simple forward – reverse with variable speed type remote control.

Our SPDT (center OFF) switch needs to have the 12v common (pin 5) connected to the center tab on the switch. Fwd (pin 3) should be connected to one of the outside tabs, Rev (pin 4) needs to be connected to the other tab. The Radio Shack switch has tabs on it that are actually sized so they can take push on – 'FastOn' type crimp-on connections. If you want to skip the soldering, at least on the switch, you could use crimp type connections here.. Unfortunately the Pot is a solder only type of connection.

When you are setting this up and labeling the switch keep in mind that inside, the switch is connecting that center wire to either one and only one of the FWD, or REV wires. AND, the pin or wire it is connecting to is the OPPOSITE of the direction the handle or paddle is pointing. There is pivot inside the switch and if the paddle is UP, then the switch is connecting the center and BOTTOM wires together.

If you apply the 12V line to FWD (pin 3) the VFD spins up the motor in the FWD direction.. When you remove the 12v signal from the pin (3 or 4 in this setup) the VFD goes into STOP or spin down mode based on the setting of function 14 “Stop Method” (the default is a controlled 5 second spin down).

In my case, if I connect 12v to pin 3 the mill runs forward, remove it and the mill stops. Connect 12v to pin 4, the mill runs reverse, remove it and it stops. That's why the switch MUST be a 'center off' switch for this type of configuration.

Variable speed is just about as simple. As the pin out diagram shows, one end of the Pot is connected to pin 8, the other END to pin 10 and the center terminal on the Pot to pin 9. The wiring diagrams for the nema enclosure versions of the VFD actually shows this kind of setup in the manuals (without the pin numbers shown!) I added them to this diagram:

With the 'hardware" all setup, what 'software' - Program settings do we need to make our remote control setup work? After the reset (function 25 set to 020 for 60 Hertz type power.) we need to set:

F 6 = Frequency UPPER limit. The Default is 60 Hz, I like to run the mill up a little higher, so I set it to 90 Hz.(And yes that means I am OVER driving the motor.. But now instead of having to loosen and swap belts, I can just dial up the speed I want... )

F 7 = Frequency Lower limit. Default is ZERO??  I set it to 15 HZ and this will be the LOWEST speed I can dial with the remote control POT.  Turning the pot to the limit of its travel will not go any lower than this setting.

F 10 = Start/Stop control  Default is for the KEYpad to control start/stop, we want the remote,  set this to 1 (terminal TM2). Which is NOT to describe a pin number, but the Terminal BLOCK.  Apparently the AC terminal block is TM1 the smaller control lead block is TM2. Because we LEFT F 3 (operation Mode) at the default setting of 0, pin 3 = Fwd/Stop and pin 4 = Rev/Stop which will cause the remote to function as we expect it to.

F 11 = Frequency Control Default is for the KEYpad (again) to control Frequency. We want remote so we set this to a 1, (terminal).

That's all the program settings we HAVE to change to make this work.  You can of course play with the Accel and Decel (braking time). You can play with Stop method settings, etc.

If you want you can use more wires and with more switches you can add; Jog, Emergency stop, etc.  Any of those 6 options listed for functions 19 and 20.

I did actually add a spring loaded momentary switch to my configuration (seen on the extreme right of the first photo) because I wanted to add an emergency stop.

What I discovered is that the Emergency stop, does the SAME THING as a regular stop if you have controlled Decel mode enabled, F 14 = 0 and the decel time, F 2 set to something low like 1.5 seconds.

You may also need to increase the DC braking time to get the VFD to completely stop the motor. But that might also cause an overload if the motor is running at high speed, at 90 Hz for example. Then you'll probably need to add a braking resistor. Check on eBay.. I got a 150 Watt, 100 Ohm resistor from China for less than $20,,

Based on what I observed I really don't see any difference between Emergency stop and a normal stop. It seems to follow the Stop Method (F 14) setting and the Decel time. If I set the Stop Method to coast, then the emergency stop just lets the mill roll to a stop. I'm either missing something as far as the setup goes or Emergency stop is a bit of smoke and mirrors.

Some functions of the FM50 seem a little ODD to me. For example I wired up my momentary switch to pin 6 and set the option to 1 – jog.  When I enable the signal nothing happens. The display on the FM50 shows the JOG frequency (F 9) I have set, but the motor does not turn.  It seems you have to do a JOG, plus FWD or REV to get that to work.  Since the FWD and REV lines “start” when you enable them I ASSUMED that the JOG, SP1, and SP2*4 commands or options would do that same. But apparently NOT. (it looks like you have to enable JOG, then also enable FWD or REV to get the motor to run.)

What I DO like about the VFD is the variable speed.  I set my Frequency lower Limit (F 7) to 15 Hz, which is 1/4 of the normal frequency and normal speed.  The VFD lets you change the “speed” even when the motor is not running. (Which kind of negated my need for 'jog'...)

My normal mode of operations now are that I do my setups on the mill, I dial the speed all the way down, which only goes down to 15 Hz, and I start the mill motor.  At that slow speed I can check for cutter touchdown.. I can also make sure things are clear.  Like the one time I had the face mill over too far and at 15 Hz, the motor just turned until the cutter hit and stopped. I immediately switched off and corrected my mistake, but it's a nice check before I really start cutting.

Once I decide my slow speed check is OK, I dial the VFD, with the POT in the “remote control” up to the speed I want to run and start cutting.  I mounted my FM 50 up on the wall actually over my lathe, in part because I plan to share it. But I also wanted to make absolutely sure that no swarf or coolants, got inside the VFD. This size unit does have a cooling fan that COULD suck stuff into the unit, and the manuals are rife with warnings about not blocking the fan..

So what does my setup REALLY look like, at least that's what everyone always wants to know.

My Teco FM-50 is mounted above my lathe on the wall, I screwed the FM-50 to a scrap piece of MDF that let me position the VFD where I wanted it while also being attached to the framing in the wall. The MDF happens to be painted white, it also had a hole cut in it, that's why it's scrap :-)

The Grounding lug and connections are on the far left, then the 220 single phase input, the LARGE white and black wires. Its a line cord I am plugging into to a wall socket for now. A more permanent installation would likely use 12 gauge wire and include a neutral connection.

The 3 phase output is on the right rear, the white, black and yes, GREEN wires.  I tagged the green wire at the motor with BLUE tape to remind anyone that opened it that the wire is HOT.. NOT ground.  That setup will probably change over time. I didn't have any 4 conductor stranded cables long enough to reach from the VFD to the Mill right now..

The “hookup wire” I used for the remote control is some kind of old computer wire. It already had brass pins crimped onto the one end and those fit nicely into the 'TM2' connections on the VFD, so I just left the brass connectors on the wire.  I do have more wires hooked up than I am actually using.

One thing that was nice about this cable is I could use the 8 primary colors for my connections. I made up a little chart as I was going along, Pin 3 = Fwd = Black, Pin 4 = Rev = White, Pin 5 = 12v = Red. So when I got to wiring up the switch and pot I could just follow the wire colors in my notes.

Here is the metal junction box with the magnet sticking to the mill's head. This box was missing all of the wire clamping hardware, so I just tied a knot in the cable as a 'strain' relief, which is perfectly fine to do for low voltage stuff like this.  You don't want an accidental yank on the wires to be pulling on the switch and Pot's connections.

I had LOTS of green electric tape around the shop so I used that instead of Black tape, so where you see green tape, think BLACK tape.

The Pot is on the left and I was concerned that the terminals MIGHT short to the inside of the metal box as I was assembling, so I insulated them by running tape all of the way around the pot.  You can kind of see the wires soldered onto the tabs of the pot. Green, Gray, and, Blue are connected to pins 10, 9, 8 on the VFD.

The center switch is the SPDT center OFF switch. It has the RED wire (12V) connected to the center and the Black and White wires, FWD and REV on the two ends.  Again, that's all of the wiring you really need.

I wanted a 'JOG' button so I added the spring loaded momentary switch that is on the far right. The center connection of the momentary switch is wired back to the red (12v) line of the other switch and the Brown Wire which is Pin 6 (sp1) is actually programmed to be JOG. F 19 = 1.  Which does not work correctly as wired because you also have to also power the FWD or REV lines to get the VFD to actually do a JOG.... That's for another day.

I went ALL OUT on the labeling.. Yes, sir, grab the nearest weird colored sharpie and start marking.  I can take the lettering off and relabel this with a little Goof Off paint clean up stuff. So it's a fast, easy and modifiable labeling system.

And that's about all there is to it..Overall the VFD is a VERY cool device. I hope this write-up can help others to complete the setup quicker and with more confidence.