ER40 collet chuck for 260???

[ventureoverland]

Hi Mal,
Did you ever get any further with the ER40 collet chuck for the 260? When we spoke some time ago you were 'thinking about it'...

If there are no plans I may need to opt for the ER32.



Thx
Jon

[cba_melbourne]

Hi Mal,
Did you ever get any further with the ER40 collet chuck for the 260? When we spoke some time ago you were 'thinking about it'...

If there are no plans I may need to opt for the ER32.



Thx
Jon

Jon, I just bought a Jacobs model 50 rubberflex collet chuck from the ebay US. Should arrive any day. Cost me $290 with postage, chuck and a set of 10 collets. The 10 collets will cover gaplessly any diameter from 0.1" to 1.06" (2.5mm to 27mm) whilst allowing through spindle stock feed of up to the actual spindle bore (25mm on the Hercus 260).I will post some pictures here once it arrives and is set up, it will need me to make a new backplate as it comes with an 1.5x8 adapter. The Jacobs collet chuck can be dialled-in axially onto a the backplate, so I hope to get minimal runout. I did also consider ER35 collets, but these would limit to 20mm clamping and need 18 collets to cover 2 to 20mm clamping range gaplessly.

I hope I made a good choice, as I have never before had the chance to use a Jacobs chuck. I shall soon see and post pics. The model 50 Jacobs collet chuck was made some 50 years ago for lathes like the Southbend 10k. They once were were expensive, about 2K in todays money, but can now be found on ebay for between 200 and 300 US$ depending on the condition of the rubber in the collets (the rubber can get brittle if it was not stored properly, just like a perished car tyre...).

[allterrain50]

Hi Mal,
Did you ever get any further with the ER40 collet chuck for the 260? When we spoke some time ago you were 'thinking about it'...

If there are no plans I may need to opt for the ER32.



Thx
Jon

Hi Jon,
Not at the moment, bigger fish to fry. Have to get the current projects finished, not to mention clearing the remaining stock.
Mal

[.RC.]

I have a piece of cast iron here that has been threaded to fit the spindle of a 260... It was supposed to be made into an ER40 collet chuck, but doing the thread was all I ever did to it...

Since I have sold my 260 it is sitting here doing nothing so free for the taking...

[scottyd]

Hey .RC., did anyone take you up on your offer? If not, id like to have a crack at making a collet chuck up.

[pipeclay]

You may find cast a little soft and to quick wearing for a collet chuck.

[scottyd]

So youd suggest steel? Im guessing vibration control isnt as big an issue given that its a collet and mounted so close to the bearings already.

[pipeclay]

Is this going on a Hercus?
I wouldn't think vibration would be much of a problem if it was mounted directly to the spindle.
If it was to be mounted via an adapter then vibration may be a slight concern.
The biggest concern would be the 1.5 mm pitch threads for the collet nut.
The price seems right so why not give it a go.
If it works great other wise let me know and I can provide a steel internal threaded blank chuck ( taper & threads need doing ) to suit either ER 32or40 for $65.00 plus post.

[scottyd]

Thanks for the offer pipeclay, ill see how difficult the whole process is. Id like to make a nut myself, so im not constrained to the 1.5mm pitch thread for clamping the collet in place. Hell, ive got some steel sitting around that wouldnt be far off the right size, but I suspect its 4140 and thatd be a bit too much like hard work. Ive made a chuck backing plate before and plenty of external threads, the only curly bit for me would be the taper. Im guessing the best way to set the compound would be to dial it off a collet mounted on a bar in the lathe?

[pipeclay]

That would work or you may be able to use an existing milling collet chuck for the taper or a sin bar if you have one.

[Tiptoeturtle]

The biggest concern would be the 1.5 mm pitch threads for the collet nut.
The price seems right so why not give it a go.
If it works great other wise let me know and I can provide a steel internal threaded blank chuck ( taper & threads need doing ) to suit either ER 32or40 for $65.00 plus post.

Do you Pipeclay happen to have a photograph of what one these looks like, that you can upload (for a 9" Hercus in my case) ?

Donald

[.RC.]

Hey .RC., did anyone take you up on your offer? If not, id like to have a crack at making a collet chuck up.

Yes it is on it's way to ventureoverland as we speak...

[pipeclay]

Do you Pipeclay happen to have a photograph of what one these looks like, that you can upload (for a 9" Hercus in my case) ?

Donald

Unfortunately I don't have any of the internally threaded 9" blanks, I do have an ER32 unfinished chuck .
This would require you to finish cut the taper.
The Chuck can be supplied with nut if required.
The Chuck would be similar to the pictured.