Would like to make collet holder for use on Optima drill sharpener.... but which collet system ?

[Milacron]

Pics below will give some idea of what I'm talking about. Collet holder would have 33mm body and if one where a nut closes the collet, the nut would need to fit in the arm and therefore no more than 33mm diameter. Therein lies the rub as a ER25 straight shank holder would have the desirable 5/8" range but of necessity, has a larger than 33mm diameter nut on the end*. ER20 would work but only 1/2" capacity.

Can you think of another straight shank collet style of at least 5/8" capacity that could be made to fit thru a 33mm bore ?





*And yes the nut could be turned down or made special but the shank external threads are too large diameter.

 

[matthewlee]

can you make your own er25 collet nut to suit the outside diameter you need?

 

[sfriedberg]

can you make your own er25 collet nut to suit the outside diameter you need?

*And yes the nut could be turned down or made special but the shank external threads are too large diameter.

 

[GM]

Maybe a nikken SK16 collet would work?...but you would need to make your own collet holder.

 

[eKretz]

Saw that too, and checked the timestamps. It was there when he posted. Almost expected to see backlash from Milacron. Historically, it was swift and often brutal,

A DA180 might work. Not sure on thread size but it should be close. A 100 would surely work but maxes at 9/16" IIRC.

 

[Milacron]

Looking at SK16 dimensions it would gain me a few thou but still wouldn't work. DA100 would work but as eKretz says...9/16" capacity...which probably is all I can go on with a standard collet design. The Optima used special long double angle collets that were a push type, thus 3/4" capacity. Still available new, holder and collets, but $$$$

 

[Peter from Holland]

A pulltype collet perhaps Like the Deckel ones
Simular system as on the SO or SOE With a hollow drawbar

Peter

 

[APD]

Looking at SK16 dimensions it would gain me a few thou but still wouldn't work. DA100 would work but as eKretz says...9/16" capacity...which probably is all I can go on with a standard collet design. The Optima used special long double angle collets that were a push type, thus 3/4" capacity. Still available new, holder and collets, but $$$$

DA180 is 1.25" diameter IIRC, which is 31.75mm and 3/4" capacity

 

[Machinery_E]

Went through this awhile back, as I started out with an Optima with limited tooling. Bottom line is there are no "standard" collets out there such as ER, TG, DA, that will accept as large of a drill that the Optima collets will. I was going to go with a custom made "push" style holder to use ER collets (instead of an external nut to maximize capacity) but before I started that project, I purchased a well tooled Optima/Mega Point.

 

[SVE Performance]

Seeing as you will be holding the drills by the flutes you will need a long collet to be able to hold the drill accurately I don't think any of the standard collet systems are long enough . I would check before modifying . Bill

 

[johnmontrose]

ER20 oversize collets are listed up to 16mm:

ER 20 (428 E)

Clamping range 1-13 mm

www.shop.santool.de

 

[wesg]

4-C might fit. 3/4" capacity, but as SVE noted there won't be much grip length to get decent alignment on the flutes, not be mention damaging them or the collet in the process.