R8 Collet Set or R8-ER32 Collet Set

Dabbler

ersatz engineer
Jacobs precision keyless - 300$.
Albrecht precision keyless

my preference: Jacobs keyed super chuck. Sometimes can be had used for 50$. Jacobs sells rebuild kits for them, and rebuilding them is easy, and the kit costs about 1/3 of a new chuck. TIR is 3 thou, but most are better.

Rohm precision keyless
Even the Accusize Precision keyless chucks are less than .005 runout.

-- If you are using a drill or a countersink this is way more than accurate enough... To achieve more accuracy, you need to do something more exotic like reaming or boring.
 

PeterT

Ultra Member
Premium Member
I mentioned this in the spindle repair post. I didn't buy from this vendor but I'm pretty sure it's what I have (rebranded) & it is very good runout/repeat. I also have a GS R8-ER collet & runout is also great so I think the brand is decent. They don't list runout but I'm sure the specs are somewhere. And if you are not in a hurry wait for a sale, KBC always seems to have one every odd month or so,
http://www.sowatool.com/Product/8/312/1338

Another consideration (maybe) is overall chuck length if you are headroom constrained. Not a lot but maybe as much as inch depending on capacity & key vs keyless. But I am very happy with keyless chucks. Also (just an opinion) if you spend good money on a precision chuck, don't use that to grip Grandpa's hand sharpened 1" bit to drill manhole covers. Precision can be lost by gronking down or irregular shanks or slippage under heavy loads... you get the idea. Use rough tools for rough service.

Also, pay attention to the arbor. A 0.0005" chuck wont do you much good on a cheapo 0.005" runout arbor. Some precision chucks are integrated with the arbor directly but I think majority are separate & you need to source, so like R8>J33 and then your chuck would be J33 socket
 

Brent H

Ultra Member
That would be quite the set of precision tooling.....remember though - your drill bits etc would all have to be precision ground to make the most of that type of set up and : you are drilling a hole which is not quite a "precision" thing. For the most part bolt holes and drilled holes typically require some clearance room. If you are looking for perfect fit, then you are reaming the drilled hole to final size or boring it out. A couple thou or .01 mm is not going to break the bank on a drilled hole.....or at least it shouldn't ....just my thoughts
 

RobinHood

Ultra Member
Premium Member
Keyless vs Keyed chuck: when using LH cutting tools (drills), the tools will come undone in a Keyless chuck. Not in a Keyed chuck.
 

YYCHM

(Craig)
Premium Member

PeterT

Ultra Member
Premium Member
Keyless vs Keyed chuck: when using LH cutting tools (drills), the tools will come undone in a Keyless chuck. Not in a Keyed chuck.

Good point, never thought about that. I've reversed out of a tapped holes without loosening but smaller thread diameters & probably low torque load in that mode.
 

YYCHM

(Craig)
Premium Member
This is kind of frustrating actually...….

Neither a set of 1/16"-3/4" by 32nds R8 collets (23pcs) or a 11pc ER32 collet set ranging from 1/8"-3/4" by 16ths can clamp the intermediate 64th sizes. Or am I missing something here?
 

YYCHM

(Craig)
Premium Member
ER collets have a much wider clamping range than you think. Get the full metric set and you'll clamp anything.

Define full metric set for 1/64"-1/2"? The increments of supplied collets don't appear to overlap them selves clamping range wise.
 

Dabbler

ersatz engineer
All ER collet sets in metric are in 1mm increments. They also have a 1mm clamping range. They do this so that they can clamp ANY size.

Let's say for argument you went with ER32 collets. They come in sizes from 1 - 21mm - that's 22 collets, and they will clamp any size in between. Little machine shop has a convenient table to show what metric collet to use for what imperial dimension.

https://littlemachineshop.com/info/er_collet_sizes.php

Your best bet for price and versatility is still my previous suggestion. There is one other alternative - get a 5C adapter and buy collets in 1/64 increments. Prepare to pay arout 1K$ or more for that solution.

i hope this puts to rest your concerns.
 

trlvn

Ultra Member
Would these qualify as quality precision components? ...

https://www.kbctools.ca/itemdetail?auto=1&itemcode=1-508-7340
Yikes, that arbor is an actual Jacobs brand and they're asking $167 for it! Accusize Tools offers arbors for $18. I used a dial test indicator on the one I got and the runout was imperceptible.

https://canadianhobbymetalworkers.com/threads/drill-chuck-for-a-mill.1582/page-2#post-16013

I would stay away from the KBC-branded arbors, however. I rejected two of those as the grinding on the jacobs taper end was terrible. Lumpy like a potato.

Craig
 

PeterT

Ultra Member
Premium Member
That's kind of the thing about Accusize or many of the inexpensive imports in general (including some so called name brand that may well originate from the same place +/- their own QC). On Monday you can get one and its bang on which makes it excellent value. The Tuesday purchase of the exact same thing or something just like it can be completely out of whack. I guess if you had an easy return recourse & are not pressed for time, the odds suggest trying the cheaper. An arbor or collet set is reasonably light to return ship but something like a lathe chuck or rotary table... not so much. I bought some Accusize annulur cutters thinking they would probably be crap but as far as I can tell, just as good as the European ones at 2X the cost. That's the other game that sometimes gets played - the good ones are produced in Asia & sold under a recognizable name brand in NAm. But sometimes manufacturer sneaks them out the back door under their own name or maybe allowed because within a non core sales area. And other times what goes out the back door is the out of spec (rejects). So what the distributor is carrying can be any permutation, it really is a crap shoot.
 

YYCHM

(Craig)
Premium Member
All ER collet sets in metric are in 1mm increments. They also have a 1mm clamping range. They do this so that they can clamp ANY size.

Let's say for argument you went with ER32 collets. They come in sizes from 1 - 21mm - that's 22 collets, and they will clamp any size in between. Little machine shop has a convenient table to show what metric collet to use for what imperial dimension.

https://littlemachineshop.com/info/er_collet_sizes.php

Your best bet for price and versatility is still my previous suggestion. There is one other alternative - get a 5C adapter and buy collets in 1/64 increments. Prepare to pay arout 1K$ or more for that solution.

i hope this puts to rest your concerns.

Yes, it does John, thanks. Almost all of the sets I have been seeing seem to start at 3mm increasing in increments of 3mm. Maybe I should be looking at ER20 rather than ER32. ER20 seems to run 1-12mm which is more the range I had in mind.

Craig
 

RobinHood

Ultra Member
Premium Member
Hi Craig,

The collets we used to upgrade your mill table/saddle were BRT Ultra Precision ER 32 and ER 16 collets. You can google then for a price. DMH here in YYC had them on sale a couple of months ago. Can’t find it right now, but I remember reading 0.0004 TIR guaranteed.

Just checked: Bridgeport Spindle > R8 to ER 32 adapter (TMX brand) > 10mm ER 32 collet (BRT) > 3/8” carbide end mill (KBC brand, made in USA) = > TIR 2-3 tenths runout. Well good enough for me.
 

YYCHM

(Craig)
Premium Member
Hi Craig,

The collets we used to upgrade your mill table/saddle were BRT Ultra Precision ER 32 and ER 16 collets. You can google then for a price. DMH here in YYC had them on sale a couple of months ago. Can’t find it right now, but I remember reading 0.0004 TIR guaranteed.

Just checked: Bridgeport Spindle > R8 to ER 32 adapter (TMX brand) > 10mm ER 32 collet (BRT) > 3/8” carbide end mill (KBC brand, made in USA) = > TIR 2-3 tenths runout. Well good enough for me.

I didn't realize we had used some ER16? I thought it was all done with ER32. After using them it occurred to me that they seemed to be the way to go rather than messing with the draw bar for every tool change.
 
Last edited:

PeterT

Ultra Member
Premium Member
Just be aware, same comment I mentioned above. Even though your collet ID may fit the smallest diameter, the physical nut might be quite large depending on what ER# you have & it may eclipse the work you are trying to look at. Picture a 1mm diameter drill extending ~25mm form your collet and a 50mm (~2" nut) on the end. The ER## refers to the nominal diameter of the collet crown in mm, nut the nut is larger again There may not be 'one set' that meets all your future needs so you may have to decide what range is optimal or a priority at this time. I use ER 90% for milling not drilling but I'm repeating myself.

Another consideration is ER collet blocks which adds a lot of functionality to your collets. ER 25 is as low as they go, I may have seen ER20 somewhere else.
https://www.arceurotrade.co.uk/cata...?node_id=705d5bc4-8d4e-40db-a730-9fb100a1d8c1

and also collet plates which I've always thought would be a better system on rotary table but people adapt them to other things including lathe
https://www.arceurotrade.co.uk/Catalogue/Collets/ER-Lathe-Collet-Chucks/ER32-Lathe-Collet-Chucks
 

Attachments

  • SNAG-8-28-2020 0000.jpg
    SNAG-8-28-2020 0000.jpg
    54.1 KB · Views: 0
  • SNAG-8-28-2020 0001.jpg
    SNAG-8-28-2020 0001.jpg
    40.8 KB · Views: 0

RobinHood

Ultra Member
Premium Member
I didn't realize we had used some ER16? I thought it was all done with ER32

Actually i think you are right Craig, we did just use the ER32s. My mind was miles ahead and I may have thought that I needed the ER16s because up until recently, I did not have a complete set of 32s that went down small enough....

good point about locking nut size and space requirements, Peter. That was my original reason to get a long, straight shank ER 16 holder: it can go into some really tight spots.
 
Top