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How to exit a dead end cut without moving the cross-slide?

bikemutt

Aluminum
Joined
Mar 5, 2022
I'm turning the end of a piece of finished round material to a reduced diameter. Once I reach the length of the reduced diameter feature, the work is done. The problem is how to get the cutter off the workpiece with out scarring it, and without moving the cross-slide, there are more than a few parts to process, this is a manual lathe.

If I release the QCTP, the cutter is still locked in because it's ever so slightly below the spindle axis; I can't lift the holder up and out, nor out and up. I think what may work is to get the cutter on the spindle axis, in theory it should then lift up and out.

There are other operations pending on the part so releasing it from the chuck isn't an option.

Thought I'd ask the experts here for ideas, thank you.
 
Perhaps you could explain the reason for not moving the cross slide? Won't you be able to put it back to the same position with the cross-slide dial, or DRO?
Yes, I could use the cross-slide, I'm trying to avoid that in order to save positioning time.
 
Back cross slide out 1 full revolution of handle (.100), move saddle out of the way, remove the part, insert new part, crank cross slide back in .100. You could do same on compound. Either you are trying to reinvent the process, or you are not clearly explaining the problem. Do you have DRO, or just using dials?
 
If I release the QCTP, the cutter is still locked in because it's ever so slightly below the spindle axis; I can't lift the holder up and out, nor out and up. I think what may work is to get the cutter on the spindle axis, in theory it should then lift up and out.
Yes, I could use the cross-slide, I'm trying to avoid that in order to save positioning time.
Removing the tool from the QCTP would be slower than moving the cross slide, especially if there's any chip contamination that needs to be cleaned.

Less repeatable too, even without potential contamination.
 
A dial is a dial, repositioning to the same mark should place the tool in the same position. What tolerance are you trying to hold?
 
I'm no expert, but for enough parts to justify building something like this https://www.hemingwaykits.com/HK1250. It's really meant as an aid for single pointing threads, so its retraction amount isn't that large. I believe Hardinge and no doubt a few others made at least some rack operated tool slides. So something off the shelf and just maybe reasonably priced might still be found on places like Ebay.
 
or a stop clamped to your cross slide vee-ways will allow accurate re-positioning, but it all comes down to the tolerance you need to hold between parts
 
I fail to see what the issue is...but in case, only a half-ass and nutty machinist would remove the QCTP with the machine running...or even with the machine off if the tool hasn't been backed off some.
 
I would use the cross slide back out , but an alternative (not sure it isn't slower) would be to open the chuck, and push the stock away from the tool.
move the carriage to clear, insert new material and tighten the chuck. Rinse and repeat.
Cheers Ross
 
If you had a Holbrook C 13 like mine it has a lever by the cross feed dial, it moves the cross feed .2, put it back and your diameter is the same as it was. Super nice for threading.
 
I often just pull back on the top of the tool post while backing the carriage off. Depending on the material and if the cut was a light finish cut it’ll pull the tool back enough so it doesn’t drag the part.
 








 
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