584,863 active members*
4,865 visitors online*
Register for free
Login

Thread: Collet sizes

Results 1 to 13 of 13
  1. #1
    Join Date
    Apr 2014
    Posts
    185

    Collet sizes

    G'day all,

    I'm just finishing off the list of stuff to buy for my PCNC 1100.

    I'm kinda lost with all the different ER Collets.

    The most common (shank) sizes that I use are: 1/4", 5/16", 3/8", 1/2", 5/8" and 3/4".

    I've already figured out that the ER-20 will do up to 1/2". But it seems that the ER-32 will go down to
    fairly small sizes as well.

    I don't quite get why they overlap the ER-20 and ER-32 collet sizes.

    If I'm starting from scratch, what's the smartest way to do this?

    All help gratefully appreciated.


    Michael

  2. #2
    Join Date
    Jun 2014
    Posts
    1777

    Re: Collet sizes

    I use the er20's mainly on my Tormach, I have about 25 of those.
    mike sr

  3. #3
    Join Date
    Nov 2007
    Posts
    2151

    Re: Collet sizes

    Er20's fill the tool trays. I do see a need for a few 32's for access to 3/4 shank tooling but not many.
    The holders become big when working on small parts and can get in the way of fixtures and part features.

  4. #4
    Join Date
    Jun 2008
    Posts
    1082

    Re: Collet sizes

    I think if you can actually plan ahead it would be smart to try to use smaller collet sizes for smaller tools. I'd say ER-16 for anything up to 1/4" (or maybe 5/16"), ER-20 for anything larger up to 1/2", and ER-32 for anything larger (that will still fit, of course). The trouble is that small tools also tend to have short shanks, when they're stuck in large tool holders it's not easy to get coolant to them effectively.

    If I was a very good planner, I'd try to have a variety of ER-16, 20, and 32 tool holders. I'm not though, so almost every holder I have is ER-20. They're not so bad with small tools and hold all the way up to 1/2" (13mm actually).

    Are you sure you're going to be using tools larger than 1/2"?

    I have Tormach's 30-piece ER-20 collet set. Since that set will hold any shank from 1/2" down to ~1/32" I know I can hold any tool shank that I'm likely to use. If I happen to do a project where I need a bunch of 1/8" tools all I need to do is make sure I have enough 1/8" collets, likewise for projects that might use a lot of 1/2" tools. If I was trying to match my tools to their holders more closely these two projects might necessitate buying more tool holders.

  5. #5
    Join Date
    Jul 2007
    Posts
    438

    Re: Collet sizes

    Is there even a 3/4" shank er32 collet chuck available?

    If so, I'd have both. I'd have many er20 chucks and a full set of collets because they are compact and affordable and one or two er32 holders and purchase collets as I needed them because they are much more expensive. This is what I do on my turning center. My er32 chucks are 1-1/4" shank.

  6. #6
    Join Date
    Mar 2009
    Posts
    1863

    Re: Collet sizes

    When I bought my machine, I ordered 4 each 1/4, 5/16, 3/8 and 1/2 inch set screw tool holders. I also ordered 6 each of the ER 16 and ER 20 tool holders. I have added a few holders since then, but I have never run out of holders.

    I set up each tool individually in the offset page and NEVER use the tool table.
    You can buy GOOD PARTS or you can buy CHEAP PARTS, but you can't buy GOOD CHEAP PARTS.

  7. #7
    Join Date
    Sep 2012
    Posts
    1543

    Re: Collet sizes

    Never use the tool table.. well I haven't either, I have the ETS and it does it on it's own. (I have ATC, if you get ATC, well.. you would use the tool table without even knowing it)

  8. #8
    Join Date
    Apr 2014
    Posts
    185

    Re: Collet sizes

    Is there really that much difference in (physical) size, between the ER-16 and the ER-20?

    Still seems odd that they would overlap so many of the sizes.

    Michael

  9. #9
    Join Date
    Nov 2007
    Posts
    2151

    Re: Collet sizes

    Quote Originally Posted by BAMCNC.COM View Post
    Never use the tool table.. well I haven't either, I have the ETS and it does it on it's own. (I have ATC, if you get ATC, well.. you would use the tool table without even knowing it)
    So many ways to get results!
    I have huge tool table setup in cam system that goes with master cam project tool table and those "about 30 currently" are setup in mach .
    I check the lengths, clean and inspect every couple weeks, and find almost no changes are required. I like and will build out over time a large dedicated tool and holder base. Its worth the money to have a large variety setup and ready to use in my programs. I bet tormach likes my thinking and adds to their sales of holders. For me its about going from cam to machine and not do much fussing with tools and offsets just load code and material and go.
    md

    I would also like to know what size the collet nut is on a er16?
    If they are smaller in diameter then I will add a couple of these to my crib also.
    As I noted on another thread, I tend to get the holders real close to work piece and rely on cam to help me spot problems.

  10. #10
    Join Date
    Jun 2005
    Posts
    653

    Re: Collet sizes

    Typical ER-16 collet nuts are ~1" across the flats, so quite a bit narrower than ER-20. You can also get narrower nuts that use a different wrench.

    I like defining certain tool numbers to certain tool sizes to make the CAM easier. They aren't always populated, but at least when code calls for tool #120, I know that's a #20 drill.

  11. #11
    Join Date
    Jun 2008
    Posts
    1082

    Re: Collet sizes

    ER-32 > ER-20 > ER-16 > ER-16M

    I'm not sure if the "ER-16M" nut is a standard size or not, but both Maritool and Glacern sell them.
    ER16 3/4-1.5MT STRAIGHT SHANK COLLET CHUCK TOOL HOLDER MariTool

    Oops, that ER-32 nut doesn't have normal wrench flats. Oh well, it's about the same size I'm sure.

  12. #12
    Join Date
    Jul 2007
    Posts
    1602

    Re: Collet sizes

    Quote Originally Posted by 300sniper View Post
    Is there even a 3/4" shank er32 collet chuck available?.
    There is a TTS version available now.

    I bought a couple to deal with the odd sized end mills. If an endmill has a 3/4" shank, one might as well just put a TTS adapter on it.

    bob

  13. #13
    Join Date
    Dec 2008
    Posts
    3110

    Re: Collet sizes

    I use the BT40 ER32, ( collet range 3mm to 20mm ), the nut diameter is something like 45mm
    - so it is awkward for tight spots, or letting coolant get to the smaller diameters to flush swarf away

    I also use the BT40 ER16, (collet range 1mm-10mm)

    I also use a 20mm straight shank ER16 collet, that can be used in a ER32 collet holder to get extra length, & also lowers the flex on the tool when compared to a extra long ER16 holder

    now I also use T/C tap holders that also use these same collets

    Cuts down on mixed holding methods

    Collets should hold shanks that fall into its designated range, never force a larger shank into a collet, as it won't run true
    - same goes if the collet has to close-up too much to grip, the tool will run-out if side cutting....drilling is not really affected, as the force is straight back up the spindle

    Not a fan of ER11, not stiff enough for varying widths / depths of cuts
    ER40....to big for the smaller machines

Similar Threads

  1. Damn it limited on collet sizes
    By stk2008 in forum DIY CNC Router Table Machines
    Replies: 4
    Last Post: 01-06-2012, 10:45 AM
  2. Collet sizes and Starting cutters
    By NVTS in forum DIY CNC Router Table Machines
    Replies: 4
    Last Post: 09-27-2010, 07:32 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •