# Commissioning and Repairing my 1994 Shoptask 1/5/10 a



## SAM in LA (Jan 5, 2010)

I received my quick change tool post from CDCO yesterday. I had ordered it on Friday 1/1/10 and it arrived yesterday, 1/4/10, via standard UPS ground delivery. So now I had to figure out how to mount it to the carriage on my Shoptask. (I realize that what I accomplished would be considered very basic in comparison to what I have seen on the site.) The threads on the QCTP stud are M14 x 1.5 and the mounting block was several inches to short. I rummaged around and was not able to find a chunk of metal to use as a spacer. I turned out that I could not see the forest for the trees because right in front of me was a block of steel that was exactly the correct size. The yellow block from my existing tool post was perfect for the job.

The only problem was the old tool post was threaded M12 x 1.75 and the new QCTP is M14 x 1.5. I then needed to adapt the two together. The easiest way to do this was to make a new stud with one end threaded M12 x 1.75 and the other end M14 x 1.5. Easier said than done.

I need to machine a stud about 6 inches long. It ended up taking about 12 of stock to do this. I cut the M12 thread 3 times before I got it right. I then threaded one end of the new stud properly. I practiced the M14 thread on a piece of scrap to make sure I had the correct dimensions. Finally I finished the new stud with good threads on both ends.
On the Shoptask, you have to manually swap out gears when you want to cut threads. The diagram supplied is not the best, so it took me a couple of tries to get it set up correctly. This is not the best picture, but you can see the gear train.

The black stud is the one that came with the QCTP, the silver stud is the one I made.

This is the completed product of my labor.


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## SAM in LA (Jan 5, 2010)

This is the completed product of my labor.

A few things that I learned from this little project are;
-Write down each step before you start machining.
-Test fit threads before you make the final cuts.
-Time required to make a part is much more than you think it will be. (7 hours to make the stud)
-Use more oil than you think you need.
-Amazed in the volume of swarf created from 0.75 round stock.
-Keep my day job, because I would starve to death if I ran a lathe for a living.
Thanks for listening. After I clean up my mess Ill figure out what to do next.
BTW  It was 25F in Lower Alabama this morning. Global Warming, Ha!


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## SAM in LA (Jan 14, 2010)

More about my repairs and modifications to a 1994 Shoptask.

I attached it as a PDF, it takes up a lot less room.

Sam 

View attachment QCTP Bushing and Boring Bar.pdf


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## SAM in LA (Apr 16, 2010)

This week I changed the headstock bearings and replaced two bushings on the triple gear in the gear box. Thm: I had tightened up the thrust bearings and ended up with oval 0.003" out of round on a 1" diameter cut. :wall: Taking the same cut after the bearings were change resulted in 0.0002" out of round. :big: I may change out the bearings in mill and see what kind of improvement results.

SAM


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## Deanofid (Apr 16, 2010)

Sounds like you're getting it pretty well whipped into shape, Sam.

"The 1994 Shoptask doesnt allow a fine enough feed rate to give a good finish, in
fact the carriage moves pretty darned fast."

Doesn't this machine have change gears? You should be able to find a ratio that will run the lead screw slower. Also, put a round nose on your cutting tool for a better finish. Maybe a 1/16" radius. Depends somewhat on the machine. The smaller the machine, or the less rigid, usually requires a smaller radius to eliminate chatter, but almost any machine will benefit when it comes to finish passes.

Dean


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## SAM in LA (Apr 17, 2010)

Dean,

My surface finish comments were from mid January. Since then I figured out that the finest feed rate on this lathe is 0.075mm.

You have to change out the individual gears to change the feed rate.

I'll try changing the radius on my bit.

Thanks,

SAM


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## Deanofid (Apr 17, 2010)

Hi Sam;



> You have to change out the individual gears to change the feed rate.



Yes, that's the way you have to do it on any lathe that uses the lead screw for the carriage feed, and that doesn't have a quick change gear box. That feed you mention should be about .003" per revolution, which will give a fairly good finish with a tool with a small radius. You should be set!

Dean


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