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Mike Hunter
12-20-2010, 10:35 AM
I’ve seen quite a bit of discussion over the years on ER collet tool holders. Kinda wondering what all the fuss is about. Currently using standard R8 collets in my BPs, what would switching to an ER system really buy me.

Thanks

Mike

Lew Hartswick
12-20-2010, 10:52 AM
what would switching to an ER system really buy me.

Thanks

Mike
The ability to use ALL drill bits within the range of the colletts, and metric shank cutters.
...lew...

JCHannum
12-20-2010, 11:18 AM
If you have a machine with an R8 spindle, the benefits would be minimal.

Approaching from the other side of the coin, what, if any, shortcomings do you feel the R8 system has in your shop that would cause you to go to a different system?

The Fixer
12-20-2010, 11:47 AM
You can use cutters with shanks over 3/4" (ER) with a more secure holding power.

dalee100
12-20-2010, 11:48 AM
Hi,

Like many things in this world, it depends.

I've used both systems extensively. Neither is inherently better or worse. It mostly boils down to how you are working and the types of jobs you are doing.

Those quick change ER systems are great when you need to have a number of tools set up for multiple part runs. Especially in manual tool change CNC.

But I don't think they hold any real advantage over R8's for onesy-twosy type work most often done in the home shop. In fact, I've found the nut to a pain in the backside when working tight to hold-down clamps and other assorted fixturing occasionally. And for holding drills? Again, nice for CNC and quick repetitive tool changes on multi part runs, but rumor has it that drill chucks have quite the size range also. And are just as easy to use for the onesy-twosy home shop work.

I guess my opinion is, unless you need the quick change aspect of ER tooling for multiple part runs with repetitive tool changes, or are tooling up a machine from scratch and have no other tooling. I would seriously consider the ER. But for general home shop type work, it might not be that cost effective to simply ditch what you have now. Nor hold much if any working advantage over the R8 in the typical home shop environment.

But only you can answer those questions.

dalee

lazlo
12-20-2010, 11:48 AM
If you have a machine with an R8 spindle, the benefits would be minimal.

Agreed, although there is a considerable convenience associated with multiple tool changes, at the cost of considerable ER chuck stick-out. I'm not sure how much of that advantage would be negated by a powered draw bar...

Chain-drilling Bridgeport motor mount slots:

http://i164.photobucket.com/albums/u15/rtgeorge_album/Servo%20Plate/ServoPlate031.jpg

DFMiller
12-20-2010, 11:48 AM
I thought the big advantage for ER vs R8 is the number of independent gripping surfaces. The R8 has three slots and thus only conforms at three points. The ER has a lot more. This should translate to better gripping and a wider range of sizes that fits.
Dave

lazlo
12-20-2010, 11:51 AM
I thought the big advantage for ER vs R8 is the number of independent gripping surfaces. The R8 has three slots and thus only conforms at three points.

The additional slots on an ER only provides a wider gripping range. You could double the number of slots again to 12 and presumably get an even larger gripping range, but you already increase runout as you grip beyond the nominal hole size of the ER collet...

photomankc
12-20-2010, 12:21 PM
I use an ER25 in a couple of situations. One, when I will be changing out tools several times because I don't have to crank up and down as much to remove the tool and ER collet as I do the R8. Another is when I want a hole drilled as accurately as I can do with a drill bit and I can beat my Jacob's chucks runout by a fair margin in a collet. Last is when I need to reach way down to the table level with a short endmill. I can't get down there with an R8 collet. The head will not lower far enough.

I like the ER25 size. Handles up to 5/8" shanks and the nut is not as large nor does it need to be cranked on as hard to clamp. I may even get an ER16 for tighter squeezes with smaller endmills. The nut can and does get in the way. For heavier cuts I stick to the R8's. A lot less stick-out from the spindle nose with those.

crancshafter
12-20-2010, 12:35 PM
Ha.
The Postman (Santa) dropped a full set of ER32 w/chuck in my mailbox to day. just unwraped them, nice and shiny, right from Hong Kong. Have had a set of OZ-collets for some years but missed the grip-range. well of to the cave and give the ER's a try:-)

Crankshafter

Mike Hunter
12-20-2010, 02:14 PM
Well, shop isn’t quite HSM…possibly one step higher… I do a lot of repetitive operations.

One that comes to mind, that got me thinking about this are dovetail cuts in barrels, rough out with ¼ inch EM (1/4 shank) then changeover to 3/8 dovetail cutter (3/8 shank). Not too bad with one or two barrels, but with with half a dozen or so, and 3 dovetails per barrel… that’s a lot of changing.

So will the same ER collet handle both ¼ and 3/8 shanks W/O changing out collets?
V/R

Mike

lazlo
12-20-2010, 02:24 PM
when I want a hole drilled as accurately as I can do with a drill bit and I can beat my Jacob's chucks runout by a fair margin in a collet.

Very true -- I should have mentioned that: a good quality ER collet chuck has runout in the tenths range, so it's vastly better than even the best drill chuck.

noah katz
12-20-2010, 02:43 PM
...rumor has it that drill chucks have quite the size range also. And are just as easy to use for the onesy-twosy home shop work.

I find that to be true only after putting a power feed on the knee (SO nice); before that cranking the knee up and down to accommodate the much longer chuck+bit to be very tedious.

Though now that I think about it, the drill bit length is a lot of the problem.

A product I'd like to see is a set of split sleeve drill bit bushings with I.D.'s matching the 1/32 and 1/64 drills and O.D.'s to the next 1/16 up.

MichaelP
12-20-2010, 03:13 PM
Aside from everything said above, I wouldn't suggest you to think about ER as of a real QUICK tool changer. To me, changing R8 is often quicker and less unpleasant than replacing ER collet.

JCHannum
12-20-2010, 05:02 PM
So will the same ER collet handle both ¼ and 3/8 shanks W/O changing out collets?
V/R

Mike

No, you will need two collets, and changeover will be more cumbersome. 1/4" endmills with 3/8" shanks are readily available so the same R8 collet can be used.

krutch
12-20-2010, 06:04 PM
The farther away from the spindle bearings you get the more flex and/or runout you could expect. Both systems have their advantage and dis-.
I recently aquired some of Tormachs' collets and have been OK with them. For those not familiar, it uses a special 3/4 R-8 collet and tool holders which locate on the spindle nose for repeat setting of the tool Z. The R-8 collet stays in the spindle and the holders have a collar to locate on the spindle. With an air type drawbar tool changer and these collets, my change time is easier and faster. So far I am happy with them. I also have some ER-8 collet holders which are OK for smaller work and work well with the Tormach holders or with the appropriate R-8 collet.

Mike Hunter
12-20-2010, 06:40 PM
Gentlemen

Thanks for all the advise, greatly appriciated.

Think I'll pass on a ER system...don't tink it will save me much time

V/R

Mike

John Stevenson
12-20-2010, 06:57 PM
I have a Bridgeport, hawk - spit - ding......................

For normal day to day work that has to be plus or minus a post code at which the Bridgy excels, I use R8 collets in metric and imperial sizes to suit the cutters used.

I also have ER25 and 32 collet chucks for those jobs that won't fit into an R8 like drills or 9mm cutters on 9mm shanks.

I made this up a few years ago, in fact we used to sell them at one stage.

http://www.stevenson-engineers.co.uk/files/R8_holder.jpg

The lower holder is a bought one from J&L but it suffers in that you can't have tall tools in it or it won't rotate.

The ones we did, above, were supported from underneath and had 20 collet spaces in the outer edge and 6 holes inside for larger tools kile boring heads etc.

Because the holder hangs in the keyhole slot it tightens the collet up enough to hold a cutter so it doesn't fall out. This allows a standard set of cutters to be ready for immediate tool change.

IdahoJim
12-20-2010, 07:19 PM
A product I'd like to see is a set of split sleeve drill bit bushings with I.D.'s matching the 1/32 and 1/64 drills and O.D.'s to the next 1/16 up.

Amen, brother, that would be the cat's a--! Or, a not-too-expensive set of R8 collets in 1/64" increments.
Jim

IdahoJim
12-20-2010, 07:23 PM
Hi,

.... rumor has it that drill chucks have quite the size range also. And are just as easy to use for the onesy-twosy home shop work.

dalee

My problem there is the 3 1/2" length of my 14N Jacobs...On some jobs it just needs too much room in the Z travel
Jim

gnm109
12-20-2010, 07:26 PM
I have a Bridgeport, hawk - spit - ding......................

For normal day to day work that has to be plus or minus a post code at which the Bridgy excels, I use R8 collets in metric and imperial sizes to suit the cutters used.

I also have ER25 and 32 collet chucks for those jobs that won't fit into an R8 like drills or 9mm cutters on 9mm shanks.

I made this up a few years ago, in fact we used to sell them at one stage.

http://www.stevenson-engineers.co.uk/files/R8_holder.jpg

The lower holder is a bought one from J&L but it suffers in that you can't have tall tools in it or it won't rotate.

The ones we did, above, were supported from underneath and had 20 collet spaces in the outer edge and 6 holes inside for larger tools kile boring heads etc.

Because the holder hangs in the keyhole slot it tightens the collet up enough to hold a cutter so it doesn't fall out. This allows a standard set of cutters to be ready for immediate tool change.


Two great minds with a single thought. I've stolen your design John....heh heh.


http://i144.photobucket.com/albums/r188/gnm109/Machinery/MilltoolHolder002.jpg

GadgetBuilder
12-20-2010, 08:24 PM
Most of my drilling is in small sizes so I have a 5/32" chuck on a 1/2" shank which fits into the 1/2" end mill holder (picture below). And, I made a short 1/2" shank for a 3/8" chuck off a dead hand drill; the short shank minimizes clearance needed when swapping that chuck for the end mill. I don't have a scheme for larger drills so the big chuck gets swapped in.

I found the drill bit pictured below in some junk from a flea market and thought I'd ask if anyone knows what they're called.(This seems like a good substitute for the drill bit bushings mentioned above.) It is a #40 drill in a 0.300 shank, made in USA with a makers mark of 4 points connected by curved lines, sort of a collapsed square.

John

http://img41.imageshack.us/img41/2701/smalldrill.th.jpg (http://img41.imageshack.us/i/smalldrill.jpg/)

Uploaded with ImageShack.us (http://imageshack.us)

John Stevenson
12-20-2010, 08:25 PM
Not quite George,
Mines a quick draw one, you only have to lift the collet up about 1" and it comes out sideways :D :p

lazlo
12-20-2010, 08:42 PM
Not quite George,
Mines a quick draw one, you only have to lift the collet up about 1" and it comes out sideways :D :p

I love that idea. I love it so much, I'm going to steal it :)

noah katz
12-21-2010, 01:24 PM
Not quite George,
Mines a quick draw one, you only have to lift the collet up about 1" and it comes out sideways :D :p

Yes, that's crucial.

Works with anything that has a fat part

http://www1.snapfish.com/snapfish/thumbnailshare/AlbumID=3452065016/a=3455608_3455608/otsc=SHR/otsi=SALBlink/COBRAND_NAME=snapfish/