Thread: Collet Chuck for the Lathe

Originally Posted by Oldneweng

Thanks Scotty. Yes I will be buying the nut.

Dean

Wuss

Give it a go! It didnt take me that long. Ive got dimensioned drawings if youre keen.

Originally Posted by Oldneweng

Another question that has come to mind. Setting the taper for the collet chuck.
Indicate and adjust taper to suit. The collet should be a firm fit on the shaft. I hope my TTA will adjust to 8 deg.

Confession time -
Once many collet chucks ago I made a chuck with 7.5 degrees. It worked (in a fashion) because I think the 30 degree taper grabbed at the front and compressed things enough. It was taken to 8 degrees a short time later when I realised the error, but to me it suggests that the ER 8 degrees is not as critical as say setting up a Morse taper. I've used the compound for all of my ER chucks so far (with a bit of a polish). The TTA will give a smoother finish but over the length of a collet while being spot on is the target I don't think that a slight error (a few tenths) will necessarily end civilisation. (Remembering too that the grade of collets that most of us buy are not likely to be spot on co-axial/ concentric either, so the "master" could be out as well) Provided the error is not great, the bore can always be bored again with the "correct" angle too.

Michael

Sounds fair enough Michael. I was going to check the TTA tonight, but I forgot.

I need to remember to make the chuck somewhat longer than needed to allow for further machining. Making the thread extra long may be a good idea as well.

Dean

I set my collet on a shaft that was drilled and tapped on the end, inserted in the 3 jaw, and the bolt tightened up to hold it square, then clocked it. This afternoon, I ground it internally to give it a polished finish, the Dremel flexible shaft makes an excellent internal grinder.
Can load pictures if required.
Kryn

Originally Posted by scottyd

Wuss

Give it a go! It didnt take me that long. Ive got dimensioned drawings if youre keen.

Ok I'm a wuss. I have very little time to spare and my silly season is about to start. Vintage. All work, no play and 72hr weeks. I also don't have any threading tooling. I can knock something up for external threads if I have to. I am waiting on the discount from Dale tools so I can buy some more tooling. He did offer to let me try some threading tools.

Dean

Originally Posted by KBs PensNmore

I set my collet on a shaft that was drilled and tapped on the end, inserted in the 3 jaw, and the bolt tightened up to hold it square, then clocked it. This afternoon, I ground it internally to give it a polished finish, the Dremel flexible shaft makes an excellent internal grinder.
Can load pictures if required.
Kryn

Did the shaft have a shoulder to tighten the collet against? I am interested in pictures.

I was thinking about grinding the taper finish with the pencil air die grinder that I bought when Rob (Nearnexus) was talking about them about 18 months ago.

I also have a Dremel and flex shaft, but the die grinder is cylindrical and narrow. A mount for the lathe is very simple to make.

Dean

Originally Posted by Oldneweng

Did the shaft have a shoulder to tighten the collet against? I am interested in pictures.

I was thinking about grinding the taper finish with the pencil air die grinder that I bought when Rob (Nearnexus) was talking about them about 18 months ago.

I also have a Dremel and flex shaft, but the die grinder is cylindrical and narrow. A mount for the lathe is very simple to make.

Dean

No shoulder on the shaft, just up against the chuck with a washer and bolt at the back. I like the KIS principle
I found that the air die grinders are noisy and the exhaust causing moisture on the lathe bed. I used the Dremel and flexible as that is what I had, that was small enough to get inside the chuck, about 60 mm, keeping the stone as close as possible to the head. The holder was a piece of 12 mm ID pipe X 40 mm long drilled to 13 mm, welded to 25 X 8 flat with a small screw holding the housing in place.
Pics tomorrow.
Kryn

I checked the TTA on my lathe finally. The scale says +/- 10 degrees so it should work fine.

Dean

Originally Posted by KBs PensNmore

No shoulder on the shaft, just up against the chuck with a washer and bolt at the back. I like the KIS principle
I found that the air die grinders are noisy and the exhaust causing moisture on the lathe bed. I used the Dremel and flexible as that is what I had, that was small enough to get inside the chuck, about 60 mm, keeping the stone as close as possible to the head. The holder was a piece of 12 mm ID pipe X 40 mm long drilled to 13 mm, welded to 25 X 8 flat with a small screw holding the housing in place.
Pics tomorrow.
Kryn

Setting the collet

Depth.jpg


Locked in 2.jpg


Set up to clock.jpg


Clocking.jpg


Start Grinding.jpg


Internal Grinder Holder.jpg

Ground.jpg

Hope these help,
Kryn

Originally Posted by KBs PensNmore

Setting the collet

snip
snip

Hope these help,
Kryn

Thanks Kryn. What type size of collet is that?

The flexible shaft I have for my Dremel has a moulded handle so it won't fit in a holder neatly like yours which is why I intend to use the die grinder. The only issue with that is that I need a good supply of air. I will have to use the extra air tank (45kg lpg cylinder). My air compressor tank has sprung a leak. It is rusty. It still works at the moment, but loses air. I will have to do something about it before using the die grinder as I don't want to run out of air half way thru a pass. It is only one of the cheap 2.5hp direct drive units. Maybe I should buy another cheapie and connect this compressor to that tank as well.

Dean

I used my pencil air die grinder to make a collet chuck for the Schaublin.

https://www.youtube.com/watch?v=HXGcLwWZeSQ

No problem.

If anyone is getting moisture from the grinder air exhaust it means their water trap/filter is not working.

Rob

Originally Posted by nearnexus

I used my pencil air die grinder to make a collet chuck for the Schaublin.

https://www.youtube.com/watch?v=HXGcLwWZeSQ

No problem.

If anyone is getting moisture from the grinder air exhaust it means their water trap/filter is not working.

Rob

Made the whole collet chuck?

I have just watched that video. I was hoping to see some construction happening.

I am now thinking about a grinding wheel to use for grinding the taper finish. CTC has some 30mm diam wheels that have internal threaded centres which screw onto the collet thread on the die grinder.

Delivered With Mounting Nut Threaded For Micro Grinder Spindle Nose

30mm Grinding Wheels.jpg http://www.ctctools.biz/servlet/the-...grinder/Detail

These seem perfect to me. Does anyone have any other ideas. Having these mounted direct to the grinder is better than on the end of a 3mm shaft and the wheel is larger in diameter than the die grinder so the front of the grinder can enter the collet chuck. The only question is whether a 30mm wheel will fit inside an ER40 chuck.

I have almost decided to go with the ER40 from CTC, as I can get an MT4 chuck and 2 extra nuts on top of the full collet set for less than the cost of 12 ER50 collets from Taiwan Tools. My only concern is freight. I got as far as the checkout at Taiwan Tools, trying to find the freight cost, but the next step was confirming the purchase. Did I miss something with regards to freight or do you have to email for a quote. On the other hand I am still waiting on a reply from CTC regarding surface freight cost. It is a bit hard to make a decision without all the facts.

Dean

Originally Posted by Oldneweng

Made the whole collet chuck?

I have just watched that video. I was hoping to see some construction happening.

Dean

Gawd Dean, you couldn't get anything easier to make.

You want instructions ???????

Rob

Originally Posted by Oldneweng

Thanks Kryn. What type size of collet is that?

The flexible shaft I have for my Dremel has a moulded handle so it won't fit in a holder neatly like yours which is why I intend to use the die grinder. The only issue with that is that I need a good supply of air. I will have to use the extra air tank (45kg lpg cylinder). My air compressor tank has sprung a leak. It is rusty. It still works at the moment, but loses air. I will have to do something about it before using the die grinder as I don't want to run out of air half way thru a pass. It is only one of the cheap 2.5hp direct drive units. Maybe I should buy another cheapie and connect this compressor to that tank as well.

Dean

Hi Dean,
I have a spare shaft if you want, for what it cost me, $15.00 plus postage. The collets I use are ER25 metric, as that is what came with the mill when it was given to me.
In regard to the air compressor, I had a couple of those and hooked them together for spraying, only just kept up. If you go to the local tip you might find a couple or more . Early last year I gave a tank from one away, as well as a NEW top assy. that was given to me the year before. I gave a friend my old one, that made 7 that he had to repair, a lot of them it's the head gasket (if you could call it that) that lets go, or the valves.
I went to trash converters to look for a larger unit, they wanted $450 for a S/H unit, went to the local Auto pro and got a brand new one with warranty and delivered for $399 (same unit) .
Kryn