Quick and Easy Expanding Collet Stop

[MrWhoopee]

I found myself in need of a second collet stop. I was about to order a simple threaded stop, when a quick survey revealed that nearly all of my collets have no internal threads. I have a Hardinge style expanding stop, but after pricing them I started looking for another option. Finding nothing acceptable, I decided to make my own. The ID of a 5c collet is about 1.020 in. I used some #210 o-rings (1 in. od), some 1 in. dia. 416 s/s and 1/2-20 threaded rod. Took about an hour.

 

[IHinIN]

Nicely done.
I’ve been meaning to make a collet stop. About half of my 5Cs don’t have the internal threads. What is the step depth and diameter on your pieces?

 

[Janderso]

I found myself in need of a second collet stop. I was about to order a simple threaded stop, when a quick survey revealed that nearly all of my collets have no internal threads. I have a Hardinge style expanding stop, but after pricing them I started looking for another option. Finding nothing acceptable, I decided to make my own. The ID of a 5c collet is about 1.020 in. I used some #210 o-rings (1 in. od), some 1 in. dia. 416 s/s and 1/2-20 threaded rod. Took about an hour.

Very nicely done.
What are you doing with these?

 

[MrWhoopee]

Nicely done.
I’ve been meaning to make a collet stop. About half of my 5Cs don’t have the internal threads. What is the step depth and diameter on your pieces?

The o-rings are nominally 1/8 section, measured .118 (3mm). Step is .100 wide x .770 dia.

 

[MrWhoopee]

Very nicely done.
What are you doing with these?

Used to provide a positive length stop when turning multiple parts. In this case, to turn 3/16 dia. to a shoulder on a bunch of 1/4 dowel pins.

 

[IHinIN]

The o-rings are nominally 1/8 section, measured .118 (3mm). Step is .100 wide x .770 dia.

Thank you.

I found this cutaway of a Hardinge stop. I may try to make one this style.

 

[RaisedByWolves]

I found myself in need of a second collet stop. I was about to order a simple threaded stop, when a quick survey revealed that nearly all of my collets have no internal threads. I have a Hardinge style expanding stop, but after pricing them I started looking for another option. Finding nothing acceptable, I decided to make my own. The ID of a 5c collet is about 1.020 in. I used some #210 o-rings (1 in. od), some 1 in. dia. 416 s/s and 1/2-20 threaded rod. Took about an hour.

I have the hardinge and love it save for use in our KO-LEE cutter grinder.

It expands the collet land too much and you cant insert it.

I might have to copy this.

 

[MrWhoopee]

Thank you.

I found this cutaway of a Hardinge stop. I may try to make one this style.
View attachment 499757

Note @RaisedByWolves comment about this style expanding/distorting the body of the collet. I've seen comments elsewhere about the same issue because of the small, localized points of contact.
Also, mine does not have the spring ejector, it is simply tapped 1/2-20 for a solid stop.