Another Power Drawbar Thread

I believe that the ER32 holder is intended for CNC use,

This does not mean that a tool holder "intended for cnc use" can not be used in a manual machine with the same spindle.
ER is a tool holding system independent of the machine spindle, do not confuse a tool holding system with a spindle taper.

Many do and this leads to much confusion, as Jim Dawson noted your machine will have an R8 spindle taper, this will require an R8 to ER collet tool holder.

Put simply you will place an R8 taper ER tool holder in the spindle then place the tools in the ER holder, simple as mud really.
If you require typical hobbyist .0001" accuracy this will not be ideal.

A typical cat spindle machine uses tool holders with a feature that allows them to be changed automatically, R8 does not support this.

If indeed you would like a good deal of accuracy and tool holding ability buy a machine from PM with an HSK spindle.
 
Yes, straight shank drill chuck, held in a collet. ER or R8, both work fine. My drill chuck has a 5/8" shank, so I just use a 5/8" collet to hold it.

The big differences are the way you tighten / loosen them, and if you want to use the collets for other stuff. Collet blocks are common for ER, haven't seen them for R8.

There is no "best" collet system. Just a bunch that have various tradeoffs.
 
Kb58, I would really look at the ER 40 if you have a lathe. I’ve heard really good things about the Shars zero set collet chuck. you could use one set of collets between the two machines. I think will be my next two purchases just seems handy to me
 
Using a drill chuck in an ER collet does add to the length from the spindle. I'm not familiar with the 935 - round column or dovetail? I find that the ER40 collet chuck (or equivalent British format) is similar stick-out to my drill chuck, so I don't often have to change the head height in the middle of a project. Changing chucks isn't much of a problem with a cordless impact driver to handle the drawbar.
 
935 is a knee mill like a Bridgeport. About 15" of Z according to the specs.

It does add to the stick out. I go the other way and use a battery drill on the knee with a 3D printed adapter.
 
One last question about ER tool holders. Looking through various threads, there are comments regarding the amount of force necessary to lock the cutter in place, that it takes so much force that a few people have broken parts in their quill. Is this a "thing", or rare outliers? I realize there can't be a black-and-white answer since some people don't post what machine they're having the problem on.
 
One last question about ER tool holders. Looking through various threads, there are comments regarding the amount of force necessary to lock the cutter in place, that it takes so much force that a few people have broken parts in their quill. Is this a "thing", or rare outliers? I realize there can't be a black-and-white answer since some people don't post what machine they're having the problem on.

Never heard of that happening. I normally use 2 wrenches on ER collets
 
Oh yeah... duh. Good point about using two wrenches (I've never seen an ER setup but instantly realized what you mean). Okay then, an non problem!
 
I went and talked to the machinists at our company. After explaining my situation, and them explaining all the options, they did point out that, unless I'm doing frequent cutter changes, sticking with a simple R8 collet set isn't such a bad thing. Some decisions to be made.

(First-world problems)
 
For the first 45 years of my chip making life I never used anything but R8 collets/tool holders in a mill. It has just been in the last 5 years or so that I have had machines that used other collet systems.
 
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