Replacing old Collets

[ltlvt]

I am looking at replacing my R8 collets on my McLane mill with ER 40. Anyone using this set up? Looking for a good source and brand. Not looking to build space ship just good shop quality. TIA

 

[ddickey]

Why are you wanting to do this?
You mean an R8 to ER collet chuck? It will add some length from your cutter to the spindle but otherwise they work well. When I had an R8 mill i had an R8 to ER32 collet chuck. I think 32 is a better size.

 

[Dabbler]

I am looking at replacing my R8 collets on my McLane mill with ER 40. Anyone using this set up? Looking for a good source and brand. Not looking to build space ship just good shop quality. TIA

I have a set of er40 and the R8 holder for them. I've used them perhaps twice in 7 years. I still gravitate to my R8s even though ER is far 'better'.

- I'm used to the R8, and so I keep using them.

 

[RaisedByWolves]

I have a set of er40 and the R8 holder for them. I've used them perhaps twice in 7 years. I still gravitate to my R8s even though ER is far 'better'.

- I'm used to the R8, and so I keep using them.

I disagree about ER collets being better. More versatile, sure, but I’ll take an R8 for holding an endmill any day, especially carbide.

 

[ltlvt]

Why are you wanting to do this?
You mean an R8 to ER collet chuck? It will add some length from your cutter to the spindle but otherwise they work well. When I had an R8 mill i had an R8 to ER32 collet chuck. I think 32 is a better size.

Mostly my age and the reach of getting to the drawbar to loosen or tighten it. I do most of my work from a walker, so I'll just say I am semi handicapped. What is better about the ER32? From what I have looked at the ER40 has a better range of sizes. Based on what RaisedByWolves said I may just buy a new set of R8.

 

[RaisedByWolves]

Can you spring for a power drawbar?

I personally don’t like them, not even sure why but for your situation it might be worthwhile.


As to quality I have an ER20 set from Icarbide for my mini mill that are great.

Er collets/collet nose are all I can use on there and it’s not great, not terrible.

The crap step in this part was due to the endmill slipping down while hogging. Didn’t change anything but came around to where I started and the endmill was taking .170 instead of .100, the **** finish is another issue (user related/abuse) altogether.






Cleaned up nice.

 

[ltlvt]

Yes I can afford a power drawbar but my use of the mill does not justify the hassle of installation and cost. .070 is a lot of slip. I may be better off just buying a new set of R8. I have 2 sets of R8's one new and one old abused set. I can get b wit what I have but the 2 mills are seperated by a room. One inside the room and one outside. I hate the idea of moving tooling in and out of the room. Good way to lose it or damage it.

 

[Dabbler]

From what I have looked at the ER40 has a better range of sizes.

I put better in quotes - because objectively it holds better, with far more contact area. But to do this, on an ER40 collet you need to apply 90 - 130 foot pounds to tighten it. Most people don't tighten them enough, and so they don't seem to work 'better'... Your mill needs a good brake or you need an adapter with flats so you can use 2 wrenches.

I disagree about ER collets being better.

In fact from an engineering perspective, ER collets win in every way. *IF* they are properly tightened. BUT I still use my E8 collets. Habit. Comfort. But not because R8 is better, because it is not.

For proper tightening, see https://www.shars.com/media/manuals/clamping-torque.pdf

There are many other sources that all agree with these numbers.

 

[mksj]

On a R-8 arbor for the mill I prefer an ER-32 size over ER-40 due to the stick out and size of the nut. ER-32 will go up to 3/4" (range is .02-.787 inches) which I find works for the majority of my milling. If you use a bearing or power nut it helps in tightening and retention, but they need to be clean of oil. Since most end mills come in standard shank sizes, you only need a limited size collet set which saves some $$. I have the Shar's R8 to ER-32 and ER 40 arbors for the mill, MT3 to ER-40 for the tailstock of the lathe and they all have very low TIR (0.0002" or better). I like the Techniks ER collets, but I also have some from Iscar,, Rego-Fix and a few others, and they have less run-out then typically seen with R8 collets. I have heard of some run-out issues, and also clamping issues with some of the cheaper metric sets when used for imperial shanks. I have only experienced pull out/slippage of a 1/2" end mill with my ER-32 collet and this was due to oil contamination and maybe not enough torque on the nut. I subsequently got high torque bearing nuts. If I run I am doing heavy milling with a 3/4 or 7/8" end mill I use an R8 collet.

R8 ER32 ER Collet Chuck Tool Holder

www.shars.com

 

[ddickey]

Mostly my age and the reach of getting to the drawbar to loosen or tighten it. I do most of my work from a walker, so I'll just say I am semi handicapped. What is better about the ER32? From what I have looked at the ER40 has a better range of sizes. Based on what RaisedByWolves said I may just buy a new set of R8.

Nothing is better about ER32 except a slightly smaller size chuck. Max size ER32 is 7/8", you probably shouldn't be using anything larger than that in an R8 spindle anyway...??