# Need A Rotating & Locking Intermediate Part.  Do They Make This?



## countryguy (Mar 1, 2016)

Hi everyone,  
My son is making something and needs a key part.  He struck out and asked me if we could buy this or something similar.  If we need to make it, we're not sure how to really approach it due to the rotating and snap-lock requirement. 

A picture is below.    There is an A side to thead into.   Same on B side.   when he puts this between his latest project, he can rotate it in 90 degree increments w/ a snap-lock type feel.   Then a release or pressure turn to the next position.   We can adapt the opening sizes on each end - But need a minimum of around 1.5" to 3" or so. 

I've looked on several sites.  McMaster, Grainger and a few specialty sites.  I simply am not sure what you call this.


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## JimDawson (Mar 1, 2016)

I'm not sure what you might call it, and I've not seen a hardware item like it.   I think I see a spring loaded detent in there somewhere.  Maybe a pin and a cam arrangement.  Looks like a good 4th axis job.


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## TommyD (Mar 1, 2016)

Thinking detent too.


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## francist (Mar 1, 2016)

Wonder if you could scrap a Rubic's cube for the working bits inside? Aside from the fact I've always wondered how those things work, I bought a small version of one shortly before Christmas. It only had 9 squares per side I think, but it had that positive "snap-turn-lock" feel that I think you're after. Cheap, like six bucks or something, in a bookstore. 

-frank


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## RJSakowski (Mar 1, 2016)

If you look at the construction of the four way tool post on a lathe, it basically does what you want.  Replace the beveled pin with a straight pin or one slightly rounded and you have it.  It shouldn't take too much work to make a similar device.


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## P T Schram (Mar 1, 2016)

RJSakowski said:


> If you look at the construction of the four way tool post on a lathe, it basically does what you want.  Replace the beveled pin with a straight pin or one slightly rounded and you have it.  It shouldn't take too much work to make a similar device.



I was thinking indexing head with four detents. Same idea, just make the two parts, bolt them together and one one, make a single impression, on the opposite piece, on the same radius as the first single impression, make four, 90' apart and go from there.


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## dlane (Mar 1, 2016)

Keep us posted 
Thanks


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## silence dogood (Mar 2, 2016)

This sounds like a bayonet mount that you see on the tail light of a car.  Or more complicated, a camera  bayonet mount so that you can change lenses.


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## P T Schram (Mar 2, 2016)

silence dogood said:


> This sounds like a bayonet mount that you see on the tail light of a car.  Or more complicated, a camera  bayonet mount so that you can change lenses.



That wouldn't allow for repeated indexing.


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## British Steel (Mar 2, 2016)

An idea of its purpose would be helpful - is it meant to deliver torque through the "snap lock", is it all rotating, is it static and purely positioning two sections relative to each other?
If it's just positioning, ball-and-spring with bevelled detents, multiply by x for a firmer location. It'll need a bit of depth, and a bolt & thrust washer or something to hold the two parts together and keep the springs compressed, of course...

Dave H. (the other one)


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## countryguy (Mar 3, 2016)

RJSakowski said:


> If you look at the construction of the four way tool post on a lathe, it basically does what you want.  Replace the beveled pin with a straight pin or one slightly rounded and you have it.  It shouldn't take too much work to make a similar device.



thanks a bunch RJ.  I think you have offered the kid a place to get into hands-on w/ that one. 

   Hope everyone here in HM land is doing well!   The kids doing very little CAD/CAM/CNC  work due to Collage Scholarship workloads.     I'm working endlessly to get the house 'sell' ready.   This project is something Mitch wants to sell to help his College fund.  ;-)   He has a nifty idea!   letting him do the work on this one more than I.


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## kwoodhands (Jul 17, 2016)

countryguy said:


> Hi everyone,
> My son is making something and needs a key part.  He struck out and asked me if we could buy this or something similar.  If we need to make it, we're not sure how to really approach it due to the rotating and snap-lock requirement.
> 
> A picture is below.    There is an A side to thead into.   Same on B side.   when he puts this between his latest project, he can rotate it in 90 degree increments w/ a snap-lock type feel.   Then a release or pressure turn to the next position.   We can adapt the opening sizes on each end - But need a minimum of around 1.5" to 3" or so.
> ...



Make both    A & B pieces with a center pivot. Scribe centerlines both ways for detents. A small pin that is spring loaded thru A will  go into detent hole B.
mike


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## Shepherd (Jul 19, 2016)

Drill holes deep enough for springs and a ball bearing at each 90 degree mark on A, and matching detents on B.  Secure a to b with a through bolt and nylock nut to control how hard it is to turn....


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## Wreck™Wreck (Jul 19, 2016)

Bearing clutch, used in automation worldwide and available off of the shelf from suppliers.
For example:
http://www.mcmaster.com/#one-way-bearings/=13cs6qm


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## Holescreek (Jul 19, 2016)

Add a narrow intermediate dial between the two threaded portions to function as a lock that holds a spring loaded detent in place until it is released by rotating the intermediate ring.


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## buffdan (Jul 19, 2016)

I wonder if there is a similar dzus fitting...Which are quick fasteners


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## 4GSR (Jul 19, 2016)

What you are needing is a spring detent arrangement.  Look for fixture components. 

Here's some design information for starters.

http://www.vlier.com/product_index/SLD/sel_06_diam.html

Some more stuff

http://www.vlier.com/product_index/SLD/pf_00_index.html

http://www.vlier.com/product_index/SLD/bb-wrench.html

http://www.carrlane.com/Catalog/ind...006280B1713050245221E0107070F1A3C3B2853504258

http://www.carrlane.com/catalog/ind...20609090C0015482013180B041D1E173C3B2853524458


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