# 5C collet stop for square and hex block



## PT Doc (Oct 28, 2019)

I am needing to make 12 short tubes. OD ~.5". Since a have both square and hex 5c collet blocks, seems that a stop for these would be just the ticket. I have a mill but no lathe.
There are a few options available and I'd like your opinions on what is worth getting.  Thanks in advance.


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## mmcmdl (Oct 28, 2019)

What exactly are you looking for ?


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## PT Doc (Oct 28, 2019)

I'm looking for a collet stop for the hex and square 5c collet blocks that will allow me set the length of the part and mill the piece to final dimension.


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## RobertB (Oct 28, 2019)

PT Doc said:


> I am needing to make 12 short tubes.



Define "short" and what is the wall thickness of the tube? You will need a stop small enough that the collet doesn't close on it yet large enough it won't go into the tube. If it's thin wall tube that may be a tall order in a ready made stop.


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## PT Doc (Oct 28, 2019)

RobertB said:


> Define "short" and what is the wall thickness of the tube? You will need a stop small enough that the collet doesn't close on it yet large enough it won't go into the tube. If it's thin wall tube that may be a tall order in a ready made stop.



Od .5"
Id .375"

Length ~ .375

Thanks


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## BGHansen (Oct 28, 2019)

Are your square and hex collets threaded for a stop?  They make threaded stops for 5-C collets.  Think I bought mine from www.cdcotools.com for well under $20.  It threads into the back of the collet.  For adjusting, you turn the rod in/out to set a depth and tighten a jam nut on the back.  When I've used mine, I set the depth to "whatever" and set in a part of known depth.  Edge find the end of that part and you'll be dialed in to the stop.

I don't think mine will get to within 3/8" of the tip of the collet, so would need a spacer or something to fill the gap.

Another method could be setting a depth mic and use that for a stop on the back side of the collet.  Slide the work into the collet until it hits the mic and tighten the block nut.  Same idea as a typical work stop on a mill.

Bruce



Generic 5-C collet stop.  Threads into the back of the collet, stop screws in/out to set the depth which is locked in with a jam nut on the far LH end.



My stop has a slot on the end for adjusting in/out



Couple of generic 5-C collets



Mine are all threaded on the back for the work stop



Work stop screwed into a 3/4" square collet.  Adjusting rod can be adjusted through the hole.



Work stop installed to a collet which in turn is in a square collet block.  I wrote the width of my collet block on the block for referencing my mill's DRO.



Also could use a depth mic as a depth stop.  Anvil would go into the back side of the collet and base would be held against the vise jaws.


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## RobertB (Oct 28, 2019)

PT Doc said:


> Od .5"
> Id .375"
> 
> Length ~ .375


Edge has a nice set https://www.edgetechnologyproducts.com/5c-collet-stop/ but they jump from 3/8 to 3/4 so you would need a spacer a little less than  1/2" dia. to go on top of the 3/8" stop.

Bruce's idea of the depth mike would be pretty easy and accurate. If you don't have a depth mike a caliper would do.

An alternative would be to chuck it up in your mill and hold a lathe cut off tool in your vise and part them off. 

Much depends on the precision you need.


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## MrWhoopee (Oct 28, 2019)

Make some soft jaws for your vise and bore to .50 dia. x .31 deep.


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## mmcmdl (Oct 29, 2019)

I have plenty of collet stops . You need one , shoot me a pm . I have regular and extended stops from Hardinge Bros.


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## PT Doc (Oct 29, 2019)

Thank you for the replies. That Edge Technology set seems pretty versatile but it’s missing the exact diameter that I need. Maybe collar on the end of one of them would work.


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## Jimsehr (Oct 29, 2019)

Another way to hold 1/2 x 3/8 part would be to buy 5c emergency soft collet and bore it to depth you want on the mill. If you bored it to .300 deep you would have a collet with a built in stop. And you can buy the collet on eBay for about 7 bucks shipped and have it in a few days. Then if you want you can keep the collet as is or rebore it to another size for a latter part. That is cheaper then buying a collet stop.
Jim


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## MrWhoopee (Oct 30, 2019)

Jimsehr said:


> Another way to hold 1/2 x 3/8 part would be to buy 5c emergency soft collet and bore it to depth you want on the mill. If you bored it to .300 deep you would have a collet with a built in stop. And you can buy the collet on eBay for about 7 bucks shipped and have it in a few days. Then if you want you can keep the collet as is or rebore it to another size for a latter part. That is cheaper then buying a collet stop.
> Jim



In the same vein, you could make a "top hat" split bushing to fit in a 3/4 collet. No need to buy anything.

One thing that hasn't been mentioned in all this is that if the OD of the parts has some variability, so will the length. It may not be an issue in this situation, but worth noting.

*PT Doc, *is that avatar a "Steal your Porsche"?


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## Bob Korves (Oct 30, 2019)

I picked up some shop made collet stop parts for almost no cost, seller did not know what they were.  They are nice, fit very well, good work.  Looking at them, they are quite simple to make.


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## PT Doc (Oct 30, 2019)

MrWhoopee said:


> *PT Doc, *is that avatar a "Steal your Porsche"?



yes indeed!


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## PT Doc (Oct 30, 2019)

mmcmdl said:


> I have plenty of collet stops . You need one , shoot me a pm . I have regular and extended stops from Hardinge Bros.




PM sent the other day.


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