I just got a nice LMV Sharp milling machine with no vice or collets. I can buy either r-8 collets or an adapter and ER 40 collets. If I get an adapter and ER 40 collets I will be able to hold larget cutteres than I could with R-8 collets.........Does anyone have an opinion on this one way or the other?????
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What collets????
- Thread starter evlwhtguy
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- Joined
- Dec 3, 2017
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- 1,911
It’s my opinion that the best course of action would be to by a 5 piece set of R8 end mill holders, and force yourself to use it as if it was the only thing that existed.
Sometimes I think we’re so spoiled with options, we spend a bunch money on options, when we should be spending a bunch of time on practicing with what we have.
Something like this is what we had at my last job. This and a boring head should keep you busy for a good long while.
Remember, the most efficient machining is done at the bandsaw. Mills aren’t the right tool for removing major sections of material, unless it’s a pocket or hole.
Then again, I’m basing this on my work, with no idea what your machining interests or jobs might require.
Sometimes I think we’re so spoiled with options, we spend a bunch money on options, when we should be spending a bunch of time on practicing with what we have.
5 Pcs R8 End Mill Holder Set Adapter Kit For With a R8 Spindle Milling Machines | eBay
<li> Specification：</li> <li>Contains 1 each R8 holders: 1/4", 3/8", 1/2", 5/8", & 3/4" diameters For double and single end (single end mill only for sizes over 5/8") Hardened and ground for durabilty and superior performance Crafted from alloy forged tool steel Drawbar End Thread: 7/16"-20</li>...
www.ebay.com
Something like this is what we had at my last job. This and a boring head should keep you busy for a good long while.
Remember, the most efficient machining is done at the bandsaw. Mills aren’t the right tool for removing major sections of material, unless it’s a pocket or hole.
Then again, I’m basing this on my work, with no idea what your machining interests or jobs might require.
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- Jun 12, 2014
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- 4,817
I have the same mill, as a general rule you would not run anything larger than a 7/8" end mill, as there are rigidity issues beyond that for this size mill. With an ER-40 holder you loose quite a bit of table to cutter height, I much prefer using an ER-32 arbor/collet system on this size mill. You also have issues of holding power and pull-out of the end mill if the ER collets are not torqued sufficiently, which is a common problem. So I recommend a using a high quality (TECHNIKS, REGO-FIX ) power nut or bearing nut with an ER arbor. Most end mill shanks are standardized to more common diameters so you something like a 1/8" R-8 collet set (1/4-7/8") works well. Anything larger than that I use a something like a shell arbor with a cutter head. I use 3/4" and 7/8" roughers for bulk metal removal, an R-8 collet will be more rigid and have less stick out from the spindle. The cheap R-8 collet sets often have higher runout as well as fitment issues if you use the arbor guide pin (which most people recommend to remove).
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- Feb 9, 2017
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- 5,252
+1. If you are trying to remove a lot of material there are no collets that will reliably retain large end mills like tool holders. If I didn’t need to be keeping my Z the same on my mill drill I wouldn’t have needed the whole set of R8’s.It’s my opinion that the best course of action would be to by a 5 piece set of R8 end mill holders, and force yourself to use it as if it was the only thing that existed.
Sometimes I think we’re so spoiled with options, we spend a bunch money on options, when we should be spending a bunch of time on practicing with what we have.
5 Pcs R8 End Mill Holder Set Adapter Kit For With a R8 Spindle Milling Machines | eBay
<li> Specification：</li> <li>Contains 1 each R8 holders: 1/4", 3/8", 1/2", 5/8", & 3/4" diameters For double and single end (single end mill only for sizes over 5/8") Hardened and ground for durabilty and superior performance Crafted from alloy forged tool steel Drawbar End Thread: 7/16"-20</li>...www.ebay.com
Something like this is what we had at my last job. This and a boring head should keep you busy for a good long while.
Remember, the most efficient machining is done at the bandsaw. Mills aren’t the right tool for removing major sections of material, unless it’s a pocket or hole.
Then again, I’m basing this on my work, with no idea what your machining interests or jobs might require.
- Joined
- Oct 11, 2016
- Messages
- 3,866
(takes a big breath)
There are about 10 threads that have discussed this... I own all 3 systems below: - But it boils down to:
Use what you are comfortable with - if you are new, here are some of the tradeoffs:
#1 High quality R8 collets will give you the least runout - minimum number of pieces from the spindle to the cutting tool. Not perfect, they suffer a little from all common North American single spit collets, with regard to holding, that is, the primary squeezing force is in the foremost section of the contact, or let's say 'lower contact area'
#2 Weldon end mill, holders (as in post #6, above (thanks, @C-Bag ) are very old school, reliable and transfer more torque than you mill can dish out. They can be hard to find (well, really good ones) and offshore ones can be hit-and-miss. Many new end mills are missing Weldon flats, rendering these holders "not recommended" for those end mills.
#3 Ah, the ER system: this requires and extra layer of parts between the cutter and the machine. *IF* you buy a very high quality adapter, and *IF* you use very high quality collets ($$$), THEN you will have minimal runout, but I'd argue a little more than #1, above. This system is designed to have high contact area. The engineering behind them is wonderful, however, you *must* learn to use them with the correct tightening torque. This can correct any of the problems in the use of them.
[A note from experience: even if you use imperial measurements exclusively DON"T buy an imperial ER collet set. It will skip sizes, and the short tightening range will make for problems gripping reground or mis-ground end mills. The full metric set will cover every single size in that ER range; You might need to post a chart of converting imperial sizes to the correct MM size...] [end of helpful advice]
---------------
The big take away here is to buy quality. Any of the mill collet systems will do the job (and there are about 20 others not covered here)
There are about 10 threads that have discussed this... I own all 3 systems below: - But it boils down to:
Use what you are comfortable with - if you are new, here are some of the tradeoffs:
#1 High quality R8 collets will give you the least runout - minimum number of pieces from the spindle to the cutting tool. Not perfect, they suffer a little from all common North American single spit collets, with regard to holding, that is, the primary squeezing force is in the foremost section of the contact, or let's say 'lower contact area'
#2 Weldon end mill, holders (as in post #6, above (thanks, @C-Bag ) are very old school, reliable and transfer more torque than you mill can dish out. They can be hard to find (well, really good ones) and offshore ones can be hit-and-miss. Many new end mills are missing Weldon flats, rendering these holders "not recommended" for those end mills.
#3 Ah, the ER system: this requires and extra layer of parts between the cutter and the machine. *IF* you buy a very high quality adapter, and *IF* you use very high quality collets ($$$), THEN you will have minimal runout, but I'd argue a little more than #1, above. This system is designed to have high contact area. The engineering behind them is wonderful, however, you *must* learn to use them with the correct tightening torque. This can correct any of the problems in the use of them.
[A note from experience: even if you use imperial measurements exclusively DON"T buy an imperial ER collet set. It will skip sizes, and the short tightening range will make for problems gripping reground or mis-ground end mills. The full metric set will cover every single size in that ER range; You might need to post a chart of converting imperial sizes to the correct MM size...] [end of helpful advice]
---------------
The big take away here is to buy quality. Any of the mill collet systems will do the job (and there are about 20 others not covered here)
Last edited:
- Joined
- Mar 12, 2022
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- 132
I agree.
Further notes: R8 tool holders with 7/16 drawbar threads are available in metric sizes. With those, the high quality and relatively cheap metric milling cutters from China can be used. I have R8 tool holders and R8 to ER32 holders, as well as ER32 collet holders for the lathe - all from AliExpress, and they have all been OK. ER collets themselves can be a different story - lots of attached cutting swarf in the slots and other defects - some cosmetic, some not.
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- Sep 28, 2013
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- 4,309
hey, you're not that far from me 
I have a set of decent R8 collets (missing the small sizes I think) and a whole bunch of milling and machining related goodies. Almost enough to open a shop
I think it's probably about a 2h drive max from where you're are to Spartanburg where I'm at now
I have a set of decent R8 collets (missing the small sizes I think) and a whole bunch of milling and machining related goodies. Almost enough to open a shop I think it's probably about a 2h drive max from where you're are to Spartanburg where I'm at now
- Joined
- Oct 14, 2013
- Messages
- 990
+1 on a high quality 5 piece R8 set! That's your go-to group. Two of the 1/2" collets isn't crazy, as you can leave a mill in one and have the other for tooling like chucks and edge finders.
Chucks and even ER holders eat up a lot of daylight... less of an issue on a big ol Bridgeport, but troublesome on my little Rockwell.
A sneaky trick to avoid cranking up and down: buy some drills, short drills, spotting drills, and center drills in 1/2" and dedicate them to the mill. After you've used that system for your spotting and hole starting needs for a while, you might add 3/8" and 1/4".
I recently had a stack up where I ran out of daylight... I had to put a drill in a loose fitting R8
worked on Teflon, so it was a win 
after that I bought a cheap set of 1/32" R8 collets for those "zero chucking length" needs. NOT my daily drivers for end mills, of course! THOSE are vintage German collets!
Sent from my SM-G715A using Tapatalk
Chucks and even ER holders eat up a lot of daylight... less of an issue on a big ol Bridgeport, but troublesome on my little Rockwell.
A sneaky trick to avoid cranking up and down: buy some drills, short drills, spotting drills, and center drills in 1/2" and dedicate them to the mill. After you've used that system for your spotting and hole starting needs for a while, you might add 3/8" and 1/4".
I recently had a stack up where I ran out of daylight... I had to put a drill in a loose fitting R8
worked on Teflon, so it was a win 
after that I bought a cheap set of 1/32" R8 collets for those "zero chucking length" needs. NOT my daily drivers for end mills, of course! THOSE are vintage German collets!Sent from my SM-G715A using Tapatalk