Logan, SouthBend, Atlas, ER collet chuck

[Ringo]

I'm going to attempt turning a ER32 collet chuck for my Logan, 1 1/2-8 threaded spindle.
I have one of the 5C chucks for it, and it is big, takes up a lot of room, feels like burrs or sharp edges in the scroll, and have had previous issues with runout.
So I will attempt a ER chuck. Spindle bore for 1 1/2-8 nose is 3/4", so ER32 will do. The same collets and collet draw nut, wrench will fit the new R8 item I just ordered.
Seems I use 3/4" dims most often as straight shanks, or blank drill rod, or whatever. ER32 made sense for me to go back forth of mill and lathe.
This will be quite the adventure, at least for me, and my machines.
I'll be internal threading to a tolerance,
internal taper boring to a tolerance,
and metric threading on a american lathe.
This could be the trifecta of goofballs.

Here is the material blank next to the 5C chuck,

[gambler]

subscribed

[nickel-city-fab]

Cool. In case you haven't seen it yet, can I recommend Halligan's videos about doing an ER chuck
https://www.youtube.com/watch?v=OZOnSnylNcI&t=20s
There was 3 or 4 videos total, same spindle you have

[Ringo]

someone made a ER40 in one of the magazines on this website, I think March 2015

[mattthemuppet]

go for it! I made an ER25 hex collet block for my Atlas 618 and use it alot. Used today actually to sidemill a flat then drill holes in the flat. Just make sure to a) leave a flat or spanner hole in the chuck and b) turn the external threads and taper (8deg?) with the chuck mounted on the spindle.

[Ringo]

yup !

[JRouche]

I bought one and havent had the need to use it. But at that crazy price why not. I will be watching. Thanks... JR

[thaiguzzi]

If you want to make it, great project, but Arc Euro Trade sells a chuck back plate and ER32 chuck for that spindle.
Just sayin'...

[Ringo]

If you want to make it, great project, but Arc Euro Trade sells a chuck back plate and ER32 chuck for that spindle.
Just sayin'...

I know there are many of them with the backplate setup. I intend for this to be native to the spindle, no back plate.
All in one piece.
And small

[rickyb]

Ringo, you won't be sorry, well except for not going to er40 or 50. I use my er40 on the 10" Logan for 90% of my projects. Can use them on my Rockwell mill and central machine 7x14 lathe. I bought metric collets as the English have small gaps in diameter coverage from what I understand.

[Ringo]

I decided ER32 because my 9x17 spindle will only pass 3/4" stock, and I want to interchange with the 6x26 mill.
The ER40 seemed a bit big for the little mill, and I cannot pass ER40 sized material thru the lathe spindle.

[BCRider]

Maybe you can't pass ER40 max size stock through your spindle but you COULD hold workable amounts of it for a few jobs. And the ER40 line DOES include a 3/4" size.

But you made a decision and you have the collets so ER32 it is!

Other than having to do an external thread for the collet nut this will be a lot like my own 5C collet chuck project. Just no drawtube.

I would also not be too quick to dismiss that 5C chuck. See if you can doctor it up and make it shine. ER collets use a full length size change. But that also means that to be accurate that you have to fill up nearly the full length or more so it grips evenly. 5C on the other hand is superb for gripping a short length step feature. To allow you to work the same way with an ER collet you have to pack the rear with a matching size or marginally smaller plug so you can grip a short step feature in the nose of the ER collet.

It's a classic case of man not living by one collet style alone. The two styles complement each other.

[Ringo]

I think my 5C chuck is deterred by the backing plate, but not 100% proofed yet
anything larger than will pass thru spindle will get the 3jaw or 4jaw by default, anyway

[Ringo]

Got a good start, internal threading

[Ringo]

and about 30seconds later, the tip chips off the carbide bit,