Custom collets

[Freddy0309]

not quite sure if this is the right place or not so apologies in advance if not.

I've recently bought a mill with a proprietary collet system but only came with one, I'm torn between getting some collets made up, some form Taylor/morse taper adaptor made or the spindle reground I'm thinking collets may be the cheapest way forward but have no idea of costs involved with any of the above does anyone know a rough ballpark figure?

 

[Spark plug]

What is the spindle taper? Is it something odd ball?

Getting a set of purpose made collets made will be very ecpensive I would emagine.

 

[Freddy0309]

It's off a George Taylor milling machine mk1

http://www.mig-welding.co.uk/forum/threads/milling-machine.63422/

http://www.mig-welding.co.uk/forum/threads/george-taylor-milling-machine.65276/

As far as I'm aware it doesn't have a taper

 

[Spark plug]

Hmmm.......

Now that is a tricky one, I take it there's no draw bar?

If there isn't a draw bar I think your best bet will be to have the spindle machined and ground to a standard ER collet size.

 

[Freddy0309]

Nope no draw bar fitted, I've been in contact with a few local engineering companies and the ones who have replied aren't interested that's why I was leaning towards custom collets

 

[Stueeee]

Didn't see the original post. Those collets look like so-called Universal collets. see here: http://gpcollets.com/tsd_main.html

 

[Spark plug]

Try some ware that specialises in machenery rebuilds grinding etc. Give Bryan Caddy a ring at slideway services.

IMO you would be much better with an ER system as each collet has a range on 1mm so each collet will hold anything within its range. If you went with fixed size collets you would need a set of metric and imperial and still wouldn't cover any eventuality, this would remove the need to hold a drill chuck in a collet for drilling as the ER collets would cover any eventuality.

 

[gaz1]

the ers dont fit either

While very early versions had plain bearings fitted to both the (No. 2 Morse taper) main spindle and the various jockey pulleys and countershaft, later versions had ball races throughout leading to much easier running and far less power loss. Almost certainly in line with the change to anti-friction bearings the spindle was modified to accept the above type of direct-mounting "double-split" collet with an included angle of 23 degrees. Although these appear to be of the modern "ER" compression type (which has an included angle of 16 degrees) they are not, unfortunately, the same and don't fit.

http://www.lathes.co.uk/taylormiller/

 

[Freddy0309]

Funnily enough the double taper ones look a lot like the one in my machine apart from the dimensions are slightly off.

I'll try Bryan caddy to see what they can do

 

[Freddy0309]

the ers dont fit either

While very early versions had plain bearings fitted to both the (No. 2 Morse taper) main spindle and the various jockey pulleys and countershaft, later versions had ball races throughout leading to much easier running and far less power loss. Almost certainly in line with the change to anti-friction bearings the spindle was modified to accept the above type of direct-mounting "double-split" collet with an included angle of 23 degrees. Although these appear to be of the modern "ER" compression type (which has an included angle of 16 degrees) they are not, unfortunately, the same and don't fit.

http://www.lathes.co.uk/taylormiller/

May be being ignorant so does that mean it can't be ground out to accept er collets?

 

[gaz1]

i could be wrong here but the 16 degrees wont fit due to it being a slack fitting so grinding out would have the same effect unless you was going to go down the route of losing some of your head to reground

its either that way or make the collets up for it

I think

 

[Freddy0309]

I have no idea either, hopefully one of the many companies I've emailed tonight to see if they take on one off public jobs will get back in touch and they'll have a better idea, even if it's making a taper or potentially making a new spindle with a morse taper/r8 and drawbar

 

[Freddy0309]

Had a few responses today and basically the responses have been I can't have it ground out to accept er collets and I would have to either modify an er collet chuck and use a drawbar or have a new spindle made

 

[Pete.]

If you can't adapt the spindle for a common collet size I would consider making a new one. It's just a piece of turned-down steel after all.

 

[Freddy0309]

It does used a raced bearing, the problem I'm getting is same as before no one seems to want to take a small on off job

 

[Freddy0309]

 

[Freddy0309]

Might not be a bad shout to put an ad up

 

[Pete.]

View attachment 87940

Hehe whoever drew that should have used an inch rule.

 

[Freddy0309]

Ah I can't take credit it's screwdrivers drawing and glad he used metric as to be perfectly honest as soon as you got down to thousandths of an inch I am completely lost

 

[Pete.]

Ah I can't take credit it's screwdrivers drawing and glad he used metric as to be perfectly honest as soon as you got down to thousandths of an inch I am completely lost

You shouldn't be because some of the dims are quite obviously wrong.