An Electronic Lead Screw controller using a Teensy 4.1

[RJSakowski]

If the lathe is being lifted, might as well install a riser. Have some 1"x4" plate that would work. Would definitely help get better access to clean out the chip pan. A little leery about levering the lathe up, just because of the high center of gravity, and the fact I would be alone. It was my first thought on how to lift it. Suppose that if I take it slow and avoid any tilt it should be ok.

Nice simple screw jack. Standard hardware and a couple of welds. I could make something like that. I will scrounge around to see if I can find some larger hardware. Bigger stuff isn't that common around here.

Place a 2 to 3 ft.long piece of 2x4 under the ways and wooden blocks under the 2x4. using the 2x 4 as a 1st and 2nd class lever,you can alternately jack up the front and back of the lathe, placing additional blocks as you go,. This is actually how I placed the risers under my lathe. Levers can be your friend. As Archimedes said, "Give me a lever long enough and a fulcrum on which to place it, and I shall move the world.".

 

[WobblyHand]

The steel I have is a bit too small for the risers, it isn't wide enough. Tomorrow I will go to the steel supplier. They have a drop area, so I will check that out first. The price quote I got for 1"x5" new steel came out to about $1.39/lb including the cut. Hope to come home with some additional materials to add to the stock pile.

My broach set arrived today. So I will be able to broach the key ways of the pulleys once I set up the arbor press on its stand. This project is keeping me busy learning new stuff, which is a very good thing.

 

[WobblyHand]

Went to the steel supplier this morning. Bought 237 lbs of steel @ $0.75/lb. Got some 1"x5.5" plate that I will make the lathe risers from and a whole pile of other steel plates. Unfortunately they didn't have any very thick cut offs. I did get some 1.25" plate to have on hand.

While sawing the steel for the risers, the blade broke. I made it half way though the first piece. Went off to buy a couple of band saw blades at Harbor Freight. They used to carry decent blades, not any more. Bought two blades, a cheap 10 pitch carbon steel blade and a significantly more expensive bi-metal 10/14 blade. I mounted the 10 pitch blade and had all sorts of issues. Mostly because it has been so long since I have put in a blade on my 4x6 saw. Had the blade pop off a couple of times including in a cut. Finally got it working right. My 4x6 is not speedy. It took about an hour per cut. It was 90F in the garage, it wasn't fun setting up the blade, nor babysitting the saw. The shutoff switch isn't set up right. It was shutting off the saw before the cut was finished. I adjusted it a couple of times, but it isn't right. Going to have to fix that hokey shutoff with a proper micro-switch sometime.

 

[WobblyHand]

Some progress, although minor in the scheme of things. Cut off a 12" x 23" piece of 1/4" plate as a base plate for my arbor press. Since it was from a scrapyard it was all rusty and sorry looking. Some wire wheel action took care of most of the crud.

Rearranged a bunch of stuff in the shop and shoehorned the stainless arbor press table (seen above) I bought from @mmcmdl into place. Enlisted my wife to help me get the table down the basement stairs. I can lift the table myself, but wanted a little help down the stairs. Still isn't permanently set up, but it is in place.

Removed the ram and the arbor anvil and picked up the arbor press and somehow got it on the table. Nearly had to put it down, but with sheer determination managed to get the press on the table. Then I reassembled the arbor press. Of course I didn't carefully check the spacing of the table supports, so had to sort of waggle both the plate and press into the correct place. The widest spot between the braces is a hair over 5". Probably do that tomorrow. Was good to have gotten that done.

Curiosity got the better of me, and the broach set was brought to the arbor press. One thing led to another and I managed to broach one of the timing pulleys. Used a 14mm collar and a 5mm broach. Ended up using 2 spacers, since the Grizzly key was rather tall. First broached the key way using no spacer, then one spacer. Did a fit check and discovered the key way needed to be a little bit deeper. Found the spacer with the 4mm broach and stacked it with the 5mm one. The pulley now snugly fits on the lead screw shaft.

The day before I worked on the spacers. They are not done yet. Having a bit of a problem getting them flat. The little 1.25" carbide fly cutter that I have is really slow. It seems like it is beating the steel rather than cutting it. Been slow going facing off these plates. I have since ordered a 2" face mill that uses the nicer cutting inserts. The current cutter gives a decent finish, but it struggles with anything over a 0.005" cut. Hard to make much progress 5 thou at a time. The size of the spacers is just larger than the work envelope of my PM25. So I have to constantly flip the piece, just to get to the other part of the piece. This is with my 4" Kurt vise. The Kurt has a relatively large fixed jaw. Think I may try clamping the spacers to the table to get a little more Y travel.

Probably be taking some aspirin soon, all the lifting and sawing has gotten me a bit sore.

 

[WobblyHand]

Broached the GT2-60T timing pulley. Machined the hub to allow the E-clip to fit. Also machined the 60T M1.5 plastic gear so that the timing pulley was inset about 1.5mm into the gear. Now my lathe is inoperative, until I finish the installation. (I do have spare pieces, so I could use the lathe, but it is a pain to switch back and forth. Won't do the switch unless I have a bigger piece to turn.) The above pieces were machined on my mini-lathe.
Here is the 2GT timing pulley installed on the lathe.

Found out why my fly cutter was behaving so poorly. Turns out the insert was chipped. Strangely, it looked like a small flat shiny spot on the very tip of the insert. The cutting edge no longer had the right geometry and literally was beating the riser steel plates into submission. Since that was the last of the original inserts that came with the Sherline fly cutter, I dug around and found some Valenite inserts that I had bought for the fly cutter. Oh my goodness, what a difference. Little blue c's and 6's again and very low noise. And the finish was pretty good for steel. So much so, I decided to redo the top and bottom surfaces for the riser plates. This time, I bolted the plate to the table so I could do the surface without flipping the piece. Have just enough Y travel to do this. Need to up my game with clamping, but it seemed to go ok.

The plates are within a thousandth or two of each other in height, so I am finished with that. It would be nice to drill them ahead of time, but I don't have a drawing of the feet of the lathe. Think I will have to place the plates then somehow mark them. Then remove and drill, and put them back. Seems like a bit of work, but don't know how to do it otherwise.

 

[RJSakowski]

Broached the GT2-60T timing pulley. Machined the hub to allow the E-clip to fit. Also machined the 60T M1.5 plastic gear so that the timing pulley was inset about 1.5mm into the gear. Now my lathe is inoperative, until I finish the installation. (I do have spare pieces, so I could use the lathe, but it is a pain to switch back and forth. Won't do the switch unless I have a bigger piece to turn.) The above pieces were machined on my mini-lathe.
Here is the 2GT timing pulley installed on the lathe.
View attachment 418182
Found out why my fly cutter was behaving so poorly. Turns out the insert was chipped. Strangely, it looked like a small flat shiny spot on the very tip of the insert. The cutting edge no longer had the right geometry and literally was beating the riser steel plates into submission. Since that was the last of the original inserts that came with the Sherline fly cutter, I dug around and found some Valenite inserts that I had bought for the fly cutter. Oh my goodness, what a difference. Little blue c's and 6's again and very low noise. And the finish was pretty good for steel. So much so, I decided to redo the top and bottom surfaces for the riser plates. This time, I bolted the plate to the table so I could do the surface without flipping the piece. Have just enough Y travel to do this. Need to up my game with clamping, but it seemed to go ok.

The plates are within a thousandth or two of each other in height, so I am finished with that. It would be nice to drill them ahead of time, but I don't have a drawing of the feet of the lathe. Think I will have to place the plates then somehow mark them. Then remove and drill, and put them back. Seems like a bit of work, but don't know how to do it otherwise.

Here are drawings of my risers.

 

[WobblyHand]

Here are drawings of my risers.

View attachment 418211View attachment 418212

Thank you. The smaller holes are for adjustment? I didn't know the location of the main mounting through holes. This fall I will make a new sturdy stand for the lathe. This current stand is not as rigid as it should be.

 

[RJSakowski]

Thank you. The smaller holes are for adjustment? I didn't know the location of the main mounting through holes. This fall I will make a new sturdy stand for the lathe. This current stand is not as rigid as it should be.

The smaller holes are for fixing the risers to the table structure below. Shims between the riser and table are used to adjust for twist, if needed. I don't run the lathe mounting bolts through to the table on my lathe. The lathe is firmly planted on the risers. This gives a more stable way of shimming.

 

[WobblyHand]

The smaller holes are for fixing the risers to the table structure below. Shims between the riser and table are used to adjust for twist, if needed. I don't run the lathe mounting bolts through to the table on my lathe. The lathe is firmly planted on the risers. This gives a more stable way of shimming.

I thought it was similar to that. My table isn't quite like that. Similar, but at the moment, can't use the leveler idea as is. I am not going to do much more to this stand. It holds the lathe, but needs various improvements that are hard to retrofit. In the fall, I will build a new stand. Too hot right now to be doing that.

Can you tell me the x-dimension of the main holes from the left edge? The headstock riser x-dimension is not legible to me. Is it 5"? The tail stock riser edge to center of hole x-dimension is 2.75"? I may go with a smaller diameter through bolt for now and graduate to the style you show after my new lathe stand is built. My steel plates are not quite the same dimensions, although similar to what you have. I left mine on the thicker side about 0.970" since I was having issues with my fly cutter. I don't have a face mill at the moment so it is tough to whittle it to size. The headstock riser is about 7.5" x 5.4" x 0.97", the tail stock riser is about 6.5 x 5.4 x 0.97.

 

[RJSakowski]

The horizontal location of the hole in the headstock relative to the left edge is 5.00" or .25" to the right of the left side of the headstock foot. On the tailstock drawing, the distance is 2,75" from the left edge or 1.75" to the right of the left side of the tailstock foot.