MadModder

The Shop => Tools => Topic started by: John Rudd on July 17, 2009, 06:33:11 AM

Title: ER collet sizes
Post by: John Rudd on July 17, 2009, 06:33:11 AM
Pardon my ignorance but I guess I should know this but....what is the difference between  ER25 and an ER32 ?
Title: Re: ER collet sizes
Post by: Darren on July 17, 2009, 06:38:01 AM
The bigger the ER number the larger the collet sizes range covers.

There is also an ER40 and I'm not sure why I or others don't select that option?

I opted for the ER32 range and find them indispensable
Title: Re: ER collet sizes
Post by: John Rudd on July 17, 2009, 07:06:38 AM
Thanks Darren...
Looks like I'll be addign a ER32 series set of collets and holder to my ' I'd like one of those please ' list
Title: Re: ER collet sizes
Post by: Stilldrillin on July 17, 2009, 08:06:48 AM
The ER32 basic set from Arc, (now with added collets) works very well for me & my Chester Conquest.....  :thumbup:

(http://i110.photobucket.com/albums/n95/Dayjo/p2250011.jpg)


David D
Title: Re: ER collet sizes
Post by: bogstandard on July 17, 2009, 09:21:56 AM
John,

There is a rather large physical size difference over the whole range. With each jump up in the size range, because the collets are physically larger, then they can have larger holes in them. So the higher the number, the more collets in the set.

I think the range goes from ER16 which is minute when compared to an ER40. It is so that you can have a range that also  matches the machines they are designed to fit. The ER40 would be more suited to the Bridgeport and above sized machines (which can handle much larger cutters), whereas the ER16 would go well on a micro mill, which can only handle the smaller sized cutters. I think the ER32 size has become the standard to be fitted to the X2 and X3 sized machines.
The other main advantage of the ER system is that each collet has a full 1mm compression range. So even though they are marked up in mm they can also hold imperial cutters just as well.

John
Title: Re: ER collet sizes
Post by: John Rudd on July 17, 2009, 09:32:53 AM
Thanks guys for the appraisal...

I'm looking to see who has them in stock.. :clap:


Update...

Looks like Warco, £37 for an ER32 holder...collets I can buy from Fleabey as and when I can afford them need them...Kewl.

The Warco holder appears unbranded....but this one http://cgi.ebay.co.uk/3MT-ER32-COLLET-CHUCK-FOR-MILLING-MACHINES-OR-LATHES_W0QQitemZ370090357893QQcmdZViewItemQQptZLH_DefaultDomain_3?hash=item562b1ab485&_trksid=p3286.c0.m14&_trkparms=65%3A12%7C66%3A2%7C39%3A1%7C72%3A1688%7C293%3A1%7C294%3A50      is made by Vertex..and I can vouch for their quality.. A bit dearer but then you get what you pay for...
 
Title: Re: ER collet sizes
Post by: John Rudd on July 18, 2009, 09:46:35 AM
Guys, what do you think of this?


http://cgi.ebay.co.uk/ER32-MT3-M12-COLLET-CHUCK-CNC-MILLING-LATHE-NEW-A75_W0QQitemZ380135637276QQcategoryZ12584QQcmdZViewItemQQ_trksidZp4340.m183QQ_trkparmsZalgo%3DSIC%26its%3DI%252BC%252BS%252BIA%26itu%3DSI%252BUS-BWR%252BUCI%252BIA%252BUCC%252BPSS%252BCRS%252BIT%252BUA%252BIEW%26otn%3D8%26ps%3D33
Title: Re: ER collet sizes
Post by: Stilldrillin on July 18, 2009, 11:15:25 AM
That looks good to me.......  :thumbup:

David D
Title: Re: ER collet sizes
Post by: Darren on July 18, 2009, 02:07:56 PM
Same place I got mine I think :scratch:

It's perfect  :thumbup:
Title: Re: ER collet sizes
Post by: shred on July 18, 2009, 02:14:43 PM
I'm a big fan of ER collets-- to hold little parts in the late and to hold cutters on a mill.  My "big" mill has an R8 spindle, but for most all cutting with 3/8" and below cutters I use an R8-to-ER16 adapter.  I tooled up around ER-16 because my little Taig CNC mill has an ER-16 headstock and can share tooling.  On the lathe, the same set of collets holds anything too small for the chucks and then some.  

If I were tooling up from scratch and didn't have the Taig, I'd look at the larger series.  I'm not sure why they don't all go to zero, but the 'minimum' size collet grows as the series gets larger, so that may be worth watching if you use really tiny drills or bits.

Here's a list of sets from one supplier:

Code: [Select]
Series  Range In.     (mm)   # of collets in set
ER11     0.020-0.275 (0.5-7)    13
ER16     0.020-0.393 (0.5-10)   10
ER20     0.039-0.511 (1-13)     12
ER25     0.039-0.629 (1-16)     15
ER32     0.078-0.787 (2-20)     18
ER40     0.118-1.023 (3-26)     23 * (see below)

Update: whoops.. that's not the entire range for the big guy, just what's in the sets.  ER40 can go to 1.14" / 29mm.
Title: Re: ER collet sizes
Post by: Darren on July 18, 2009, 02:17:40 PM
Ah.....that's good to know.... :thumbup:
Title: Re: ER collet sizes
Post by: bogstandard on July 18, 2009, 02:29:23 PM
I got it wrong in my above statement, I suppose because I only take notice of what I am interested in.

Similar to Shred's chart, but a little more expanded. Rooting about on the site where John is considering buying his holder from, I found the complete picture on the size range of ER collets. So I hope this is correct.

Bogs


Quote
I'm not sure why they don't all go to zero,

When you fit a collet into the nut, you will find that the ones with the large holes in them go in a lot easier than the ones with the very small holes. This is all to do with deforming the collet to get it to 'snap in'. The ones with small holes have a lot more meat left in them to deform, maybe that deformation has something to do with why they can't go to zero. Without a very small hole in there (0.5mm), there would be nowhere for the deformed metal to move into while you fitted it into the nut, and so it just wouldn't be able to be fitted.
Title: Re: ER collet sizes
Post by: John Rudd on July 18, 2009, 03:58:02 PM
Thanks for the info guys...Looks like I'm buying.... :clap:
Title: Re: ER collet sizes
Post by: shred on July 18, 2009, 05:21:08 PM
Thanks John.. that makes sense. The little ones are tricky to get in and out of the nut.  I keep my 1/32" ER16 in it's own nut for that reason.  It will hold the really tiny drills since it starts a little smaller than 1mm but it's a nuisance to get in and out.

Egads, they make an ER8?  I saw an ER11 the other day and first thought it might be some sort of tiny novelty joke collet.   :scratch:


Title: Re: ER collet sizes
Post by: John Rudd on July 18, 2009, 05:38:29 PM
Same place I got mine I think :scratch:

It's perfect  :thumbup:

OK bought one...If its a pile of crap I blame Darren :lol: and I want my money back......
Title: Re: ER collet sizes
Post by: Darren on July 18, 2009, 06:04:42 PM
Blame me for everything, I don't mind......

Thorngumbald you say....got a very good mate in Scarby...... :coffee:

 :lol: