Pultra 10mm Collet Blocks

OK I know this is a long shot, but before I set to and make some, has anyone come across any commercially available ones.

What I am talking about are the four and six sided blocks to hold collets, they are typically available for ER and 5C etc.

Those are too bulky for my needs, and I would like a set to take my 10mm Pultra 1770 collets for doing really small work on the Boley jig borer. I have every imaginable size and shape of collet, so it makes sense to use them on more than one machine.

Thanks

Phil

I've seen nothing commercially available, recently, Phil

A few years ago RDG did have a few 'bench' collet holders for 10mm Pultra collets, but I missed out

Hearsay was that they were specials made for BAe, but I don't know for sure.

If you do locate any, do please let me know.

MichaelG.

I've only ever heard of them for 5C. I kept suggesting to the late John Stevenson that he make some for 3C since there are so many of those collets around for Boxfords. 6, 8, 10mm sizes would also be logical developments of the theme.

As I suspected.

The only thing I have managed to find is on this website, he calls it an upright collet holder but it is not really what I am after.

**LINK**

Looks like I will be making my own then.

Phil

.

That's very similar to the one I mentioned ... useful, but not what you are looking for.

You presumably want something more like the ones I pictured on this thread from 2017:

**LINK**

https://www.model-engineer.co.uk/forums/postings.asp?th=131257&p=2

MichaelG.

Yes Michael

That's the sort of thing, in fact I have just this minute finished drawing a set up in Solidworks 3D CAD.

Watch this space !!

Phil

OK, if anyone is remotely interested, here are my Solidworks drawings in JPG format.

Just bear in mind that I have not actually made them yet, so they may possibly change.

The plan is to bore the 10mm collet hole and taper in the square and hexagon raw materials, then use a mandrel to hold them in the dividing head to finish the flats to size on the milling machine.

Phil

Many thanks for sharing that, Phil

MichaelG.

The one thing I'm always wary of with the 5C blocks is that when you use them vertically they are stood on the end of the collet as it and the nut stick out the end, not a problem with ER blocks.

I wonder if this could be avoided if the block were made a little longer and a recess cut for a "nut" that could be tightened with a two pinned spanner so nothing stuck out the back. Possibly make a second larger flanged nut too for when you want that to act as a stop as discussed previously in Michael's linked thread.

Jason

Fair comment.

I have made the nut so it is machined on both sides and also so that the collet cannot poke out of the end for that very reason. I did wonder about a recessed nut, but thought it over complicated the design.

Phil

.

[my emboldening]

Jason: If you scroll down Phil's recently linked page: **LINK**

http://www.wefalck.eu/mm/tools/attachments/attachments.html

... to 'Upright Collet Holder'

You will see that's exactly what was done [albeit on a much smaller scale than 5C]

MichaelG.

Hi Phil

I have some Pultra 10 collets so I am interested in making the collet blocks'

The problem I have is getting the correct size taps to make the nuts for the collet.

Could you give me the Tap size and where could I get the Taps from.

Cheers

Malcolm

Be careful here. Pultra 10mm collets are not the same as Pultra10 collets, which are probably 8mm collets.

If you are making the same as Phil's then the thread size is on the drawing . M10 x 1 which is quite common as it is a spark plug thread

The 8mm collets have a thread 0.268" dia x 40tpi, I think I have seen this size tap somewhere as several collets use the thread. Shouldalso be able to single point them on the lathe with a small tool.

Phil P -- thanks for posting your excellent and very clear drawings.

I am thinking of making a pair of these collet blocks, and maybe a third one in a cylindrical form. Can I ask - did you make them, and did you make any changes that were advantageous?

I was thinking of using Jason's idea of making recessed nuts, for instance.

Thanks

Colin

I am in the process of making some er16 blocks so they can be used in the sherline. My only complaint with my er25 blocks is that I find them a bit on the short side a problem I hope to get over when doing the er16 version.