[tanky321]

I recently bought an ER16 collet chuck on ebay. After receiving it I noticed that the inside of the nut has an offset circular hole in it. It almost looks like it belongs, but im not sure, thats why I come here! Does this look correct?

Pictures, its really hard to get a good angle.

[wantacnc]

Yes the oblong hole is proper for the Er collet nut any series. The collet snaps into the hole and it also assists in releasing the cutter when you loosen the nut. To remove the collet from the oblong hole you lean the collet to the side and pull out.
Joe

[Bob La Londe]

Yes, that is the "Eccentric Ring" that holds the collet in place. Its the magic dohickey that pulls the collet out of the chuck taper when you unthread the nut.

[tanky321]

Great! Thanks alot!

Now I just need to find some 8mm angular contact bearings for it!

[Bob La Londe]

Great! Thanks alot!

Now I just need to find some 8mm angular contact bearings for it!

VXB.com or Ebay.

[ssutton]

On the subject of ER16 collets. Do you mount these into your routers chuck for more reach or what exactly is the purpose of them?

Scott

[fizzissist]

Instead of buying 2 ER 16's, wouldn't it be cheaper to just buy one ER 32?

[Walky]

On the subject of ER16 collets. Do you mount these into your routers chuck for more reach or what exactly is the purpose of them?

Scott

They can be used for that (I don't see much need for extended reach in most cases, though) and also to broaden the range of available collet sizes, but at the cost of increased runout. As I see it, their ideal use is to build spindles from scratch (there are quite a few related builds on the forum using those).

[tanky321]

I'm building a spindle from scratch for a small commercial engraver that I couldnt get collets for. I'll post some pics as I go on.

Instead of buying 2 ER 16's, wouldn't it be cheaper to just buy one ER 32?

I'm not sure I follow you, I only bought 1 chuck. I took a bunch of pictures because I found it difficult to get the right angle.

[Bob La Londe]

I'm not sure I follow you, I only bought 1 chuck. I took a bunch of pictures because I found it difficult to get the right angle.

humor

[tanky321]

Dont know if I should have started a new thread, but im also trying to figure out how to hold the entire assembly together.

I'm going to have a set of angular contact bearings, compressed by the collet chuck. Now, I have no idea how to compress the assembly. I was thinking a shaft collar, but I feel like that may not be a great solution. Ideally I would want a threaded portion on the shaft, similar to a led screw.

Any ideas?

[Bob La Londe]

I think the better spindles are usually made with 3 bearings. Two back to back ACBs at the nose and a third bearing at the back right below the pulley. The third bearing isn't always an ACB.

An ACB pair is designed to be squished together to tighten up the endplay. Atleast one vendor suggests that you contact them if you plan to use them that way as not all ACBs are created equal.

The way you have it threading the shaft is an option. I am not crazy about spring collars either, but if you used a thrust collar/washer and spring to hold them snug it might be an option.

[rowbare]

Have you read this thread? It is a beautiful example of a shop built spindle based on a collet chuck. http://www.cnczone.com/forums/cnc_wo...dle_build.html

bob

[tanky321]

The only difference I can see is that the end of the shaft is tapped, allowing him to bolt through for retaining. I may end up drilling and tapping mine to use the same approach.

[victorofga]

im not sure you try to drive with this assy... but i like to think, the bearing behind the collet should be at least 12mm and should connect with a radius..

the 12 mm bearing still can be used permanently over 20K rpm
on your picture that grove known as ""break point""" in a design..
so the machining there should be a radius only, no grove..



i think if you using two angular contact bearing, then between bearings need an exactly machined spacer..
what you showed design i believe works well with taperroller bearings..

[Bob La Londe]

On the subject of ER16 collets. Do you mount these into your routers chuck for more reach or what exactly is the purpose of them?

Scott

They can be used for that (I don't see much need for extended reach in most cases, though) and also to broaden the range of available collet sizes, but at the cost of increased runout. As I see it, their ideal use is to build spindles from scratch (there are quite a few related builds on the forum using those).

I have one with a 1/2 straight shank that I used for greater range of tool holding in a 2HP PC690 router. I cut the shank down to be just long enough to full engage the collet and nut that came on the router. Yes, it has more runout, but not so much when cut down short like that that I can't use standard ME consultant produced feed and speed numbers on small tool.

I'm building a spindle from scratch for a small commercial engraver that I couldnt get collets for. I'll post some pics as I go on.

8mm is the bore of a standard skate bearing. You can get them in grades from unknown to ABEC 9. They are not ACBs, but I know of one small mill maker that uses them with a spacer like ACBs on their lead screws.

I've played with the idea of making my own spindles using these a number of times. Keep us aprised of your progress please.