Modifying Top Slide For QCTP

Allan

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I have a new QCTP but it is meant for a T slotted top slide. Mine has only a single bolt. The bolt passes through a raised "collar" which is integral to the top slide. In order to use the new tool post I have to remove the collar portion. My question is how best to do so. I have a lathe and a drill press. These are the options I came up with:
1. drill it off with the drill press. Seems a bit crude but easily set up.
2. put it on a face plate on the lathe and turn it off. Or
3. Cut it off with a hacksaw and file it level. Also crude.

So how would you do this or do you have a way to leave it in place and still get the TP to fit?
Al
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I'm all for modifying tooling but always weary of cutting off OEM parts. would you be able to turn a ring to sit between the compound and the QCTP? or would that raise the TP too high up?
 
If Sharon's idea won't work for you, I would use the faceplate method or find a buddy with a mill.
 
I'm in the same situation

so to modify the QCTP and leave the lathe tool post intact is my route...the collar is called a boss...these guys leave it in.

Here is a link with detailed instructions.
http://www.cnccookbook.com/MTLatheQCTP

video of another guy who did the same ... not as detailed

http://www.youtube.com/watch?v=JK-SjoKnjDc

here is the basic plan...Note that these are not all the correct measurements of my or probably your toolpost, but the concept seems sound

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Is it possible to counterbore the toolpost?

That's probably what I would be looking at doing. I would think you would be able to bore it out on the lathe and not be in a danger of contacting the inner mechanism in the post. You should be able to see if it's "doable" when you disassemble the post to put it on the lathe.

It would also be nice to know just how the post on the compound is connected to the slide. Maybe you could still use it or maybe you'd need to make use of the one that come with the QCTP. I can't really tell from the pics how much they differ in diameter and length.

-Ron
 
Thanks to you all.
I will peruse the QCTP and see if it looks feasible to counterbore it. I always like to run these things by other people. When I was flying, the Aviation Safety Letter used to say, "Learn from the mistakes of others because you won't live long enough to make them all yourself". I try to hold myself to that.

Sharon, I'm of the same mind. I hate to make irreversible changes to the OEM design. I think the wider collar around the boss will make it too high.

Giorgio, thanks for the links and thoughts. The stock bolt is too short to reach up through the TP. The original and new bolts are very similar in OD so I'm not sure if the sleeve is the best option. I can probably modify the new one of make one to fit. The original bolt has a round head on it about 1/8" thik. It has a lug on one side to prevent it from turning. It shouldn't be too tough to duplicate it.

I like the idea of retaining and using the boss. It just seems to be a more rigid proposition. Again, thanks.

Al
 
in that case, I'd also opt for counterboring the tool post. will also give you extra friction support.
 
This was my first project on my machine.

The standard tooling was a 4-way toolpost and I wanted to use a QCTP. I took apart the crosslside and found that the stud was held in with a very slight press fit and a roll pin to prevent spinning. I removed it to take some measurements, reassembled the whole thing and used the 4-way to make a whole new stud. It took a while to machine the majority of the length down to the final diameter while leaving the large shoulder, but it was a good exercise.
 
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