ER32 Collet Chuck

So I have been looking for a collet setup for my 9A. I have considered the 3C setups, but have decided against them due to cost and the limitation on the already small stock that can pass through. I also considered a 6K setup with a 10K spindle upgrade but that becomes stupid expensive.

I considered a 5C chuck, but cost is still higher than I wanted to spend and the 5C chuck really reaches out farther than I would prefer for a collet adapter. It would, however, be fast and allow the full spindle bore to be used.

I then found a number of threads on using the ER32 and ER40 collets. Since I would want to maximize precision, I decided against the several one piece 1 1/2-8 to ER32 chucks I found. I would either need to make one myself on my lathe or get a plane back chuck. Although these chucks are pretty reasonable, they were still more money than I wanted to spend.

Well, I found one at hhip.com. I had never been to their site before. It seems like many of the other US sites selling Chinese machine tools. However I got to their sight because Google led me to a $62 plain back ER32 collet chuck. They also had a matching backplate with 1 1/2-8 threads and the three through holes pre-drilled for another $26. So I was able to get into a new ER32 setup for my 9A for less than $90. Collets are cheap and plentiful on fleabay. I paid $54 for a 19 piece metric set which runs from 2mm to 20mm. That should more than cover any size stock (metric or imperial) up to the spindle capacity.

I will have to machine the backplate to determine how accurate this thing really is, but it "looks" really nice. I will report back when I get my High School 9A up and running and get the backplate machined.

Part numbers are 3901-5032 and 3900-3112. I got the three inch (80 mm) chuck because I figured the smaller the better (they also advertise a 4" - 100mm chuck). I will take a lot of material off the backplate as well to snug the whole assembly up as close to the spindle as possible. This setup should allow me to pass 3/4" stock all the way through the spindle. It also allows me the versatility of running an MT2-ER32 chuck in the tailstock and an R8-ER32 chuck in my mill/drill for one set of collets for nearly every occasion.

If anyone is looking for an alternative to the original 3C setup, I don't know how you could beat this without making the chuck yourself (which is, of course, a perfectly good alternative).


Baxter

I just contacted them and they don't have the ER40 chuck, "check back in a month or two". However, Glostertooling.co.uk does have them but shipping is about 25 Pounds.
Karl

A problem with ER chucks, is the amount of torque required on closer nut, for proper grip.

Enough to take teeth off of your cast iron backgears.. 100 ft lbs is recommended torque.. ER 40 is 130 ft lbs..

Slow collet change.. and twice as many dirty parts to wipe clean, every collet change...a problem on a lathe..

Jacobs Rubberflex system worked and looked good....

The proper factory equipment allowed lever closers, very handy for multiple same sized work.

5C collet chuck works fine on a SB, and has a MUCH larger selection of collets.. step,internal expanding, square, hex. emergency, Easily handles depth stops..

Using a tool holder only to hold work, is just wrong

What do they say about something sounding too good to be true?

I guess, at the least, I should set the chuck up to allow the use of a spanner wrench opposite the collet wrench to resist the temptation of using the back gears to hold it while tightening. At least I don't have too much money invested in the chuck and the collets will definitely serve multiple purposes.

Baxter

abarnsley said:

A problem with ER chucks, is the amount of torque required on closer nut, for proper grip.
Enough to take teeth off of your cast iron backgears.. 100 ft lbs is recommended torque.. ER 40 is 130 ft lbs..
Slow collet change.. and twice as many dirty parts to wipe clean, every collet change...a problem on a lathe..
Jacobs Rubberflex system worked and looked good....
The proper factory equipment allowed lever closers, very handy for multiple same sized work.
5C collet chuck works fine on a SB, and has a MUCH larger selection of collets.. step,internal expanding, square, hex. emergency, Easily handles depth stops..
Using a tool holder only to hold work, is just wrong

Click to expand...

I have to disagree with you on this. One shouldn't have any problem getting the nut tight enough and if they're THAT concerned, put flats or pin holes for a pin spanner on the chuck. Non existent problem solved.

Plus, the ER collets are intrinsically more accurate than 5C collets, have a more versatile clamping range, and colet for collet - are less expensive. Depth stops are easy, so moot point there. Even the expanding collet point is moot, simply because they're available as plain round ones as well. ( although I usually make mine )

It's a good enough choice that having the option to do whatever I wanted to my Hobber, I chose ER40.

panabax said:

If anyone is looking for an alternative to the original 3C setup, I don't know how you could beat this without making the chuck yourself (which is, of course, a perfectly good alternative).


Baxter

View attachment 140446View attachment 140447View attachment 140448

Click to expand...

That's what I did. As far as tightening the chuck, I milled grooves on it for use with two spanners - no need to rely on the back gear. Here's a photo of it on the lathe.

Ping iwananew10k
I'm pretty sure he did something like that....

An ER collet is a poor relative of a TG

TG's are available to 2 inches...

A Hobber is not likely spinning HR or CR steel as run...

A plain bearing SB, is not going to stretch the accuracy argument of 5C vs ER.

Still no hex or square collets for ER.. Or emergency collets for making those eccentric parts.. 5C is just plain more flexible.. Those 5C collet blocks (hex and square) are a time saver.. Collet blocks would be clunky in ER..

Nice having lathe collets by lathe, and mill collets by mill, never have both machines needing same collet at same time... (Except for those handy 5C collet blocks)

Nothing like getting 2 wrenches to do something.., That I can do with a flick of my wrist, While spindle is turning..

Or with same chuck key (5C chuck) that fits my 4 jaw.

5C collets were invented/intended for workholding (work that is often very slightly irregular) and not precision ground like an endmill shank.. Getting a raw piece of CR steel spinning to .0005 is fine, Not so fine spinning an end mill .0005 out..

Using mill tooling on a lathe, might save money.. Will NEVER save time... Which is money to me..

For example if I have around 40 ea 3/16 rivits, to modify heads on... ER collet, 5C collet chuck, or Lever closer???.. No way am I going to even think about ER..

abarnsley said:

An ER collet is a poor relative of a TG

TG's are available to 2 inches...

A Hobber is not likely spinning HR or CR steel as run...

A plain bearing SB, is not going to stretch the accuracy argument of 5C vs ER.

Still no hex or square collets for ER.. Or emergency collets for making those eccentric parts.. 5C is just plain more flexible.. Those 5C collet blocks (hex and square) are a time saver.. Collet blocks would be clunky in ER..

Nice having lathe collets by lathe, and mill collets by mill, never have both machines needing same collet at same time... (Except for those handy 5C collet blocks)

Nothing like getting 2 wrenches to do something.., That I can do with a flick of my wrist, While spindle is turning..

Or with same chuck key (5C chuck) that fits my 4 jaw.

5C collets were invented/intended for workholding (work that is often very slightly irregular) and not precision ground like an endmill shank.. Getting a raw piece of CR steel spinning to .0005 is fine, Not so fine spinning an end mill .0005 out..

Using mill tooling on a lathe, might save money.. Will NEVER save time... Which is money to me..

For example if I have around 40 ea 3/16 rivits, to modify heads on... ER collet, 5C collet chuck, or Lever closer???.. No way am I going to even think about ER..

Click to expand...

I agree with you all the way. Those er collets are fine if you only use them to hold precision ground tools and you replace the collet nut the instant it starts to get worn, if you don't you will booger the extraction grooves on your collets and the nut will come off and not pull the collet out, and you will have a bad day.

littlemachineshop.com has 3C collet closers for lathes with a #3 MT spindle taper for around $100.

Another tool in the box is never a bad thing. I have ER32 collets for TTS tooling on my mill, ER32 collet chucks for 3MT for bigger stuff on my mill than the TTS tooling can handle, and also for the lathe. A 2MT ER32 chuck for the tailstock of the lathe, and am getting an ER32 face plate very similar to yours.
Is it the best for all occasions? No, but nothing is preventing me from using other tools when they'd be more appropriate.

Putting aside the question about the appropriateness of the ER32 collet chuck, the one identified above turned out to fully meet my expectations. After machining the back plate on my spindle, I measured a TIR on the inside taper of the collet chuck at less than .0005". In fact, it barely moved the needle at all. Given the price, and what I was hoping to accomplish, I am very satisfied with the collet chuck. I have already turned a couple parts with it for my lathe and it worked great. It is much better at holding small parts, especially threaded parts that are easily marred up by the 3 jaw chuck.

Thanks for all the feedback,

Baxter