What Material To Us For Vise Jaw That Will Compress Slightly More Than Aluminum?
Close
Login to Your Account
Page 1 of 2 12 LastLast
Results 1 to 20 of 28
  1. #1
    Join Date
    May 2006
    Location
    Illinois
    Posts
    291
    Post Thanks / Like
    Likes (Given)
    105
    Likes (Received)
    57

    Default What Material To Us For Vise Jaw That Will Compress Slightly More Than Aluminum?

    I'm cutting the vise jaws for a production run of 200 small parts. I want to hold 15 parts across a 10" vise jaw. I've done this in the past with 6" jaws but if one or two of the parts are say, .002-.003 out of tolerance, the shorter parts come out of the vise.

    My thought is to use a plastic material on the front vise jaw to allow a little compression and take up any slack. There's very little machining force on the part for this second operation.

    I picked up some Delrin to try, (this is my first experience with Delrin,) but now that I have the Delrin on the bench, it seems almost as hard as 6061.

    Do you think the Delrin will compress enough or do I need to look into a different resin material?

    Thanks!
    gm.

  2. #2
    Join Date
    Nov 2017
    Country
    UNITED STATES
    State/Province
    California
    Posts
    369
    Post Thanks / Like
    Likes (Given)
    248
    Likes (Received)
    244

    Default

    Nylon might be the ticket here. The problem to watch for is the plastic deforming and staying that way.

  3. #3
    Join Date
    Feb 2010
    Location
    ch
    Posts
    3,381
    Post Thanks / Like
    Likes (Given)
    279
    Likes (Received)
    471

    Default

    delrin/acetal has a compressive modulus about 1/25 of aluminum.

  4. Likes mhajicek, TeachMePlease liked this post
  5. #4
    Join Date
    May 2017
    Country
    UNITED STATES
    State/Province
    Minnesota
    Posts
    2,118
    Post Thanks / Like
    Likes (Given)
    2897
    Likes (Received)
    1520

    Default

    Yes, Delrin is far softer / more compressive than aluminum. I was going to recommend PEEK, as it's significantly harder and stronger than Delrin, though it would be a bit pricey.

    Edit:

    What about using aluminum for the solid jaw with a pocket, and plastic just for the moveable jaw?

  6. Likes TeachMePlease liked this post
  7. #5
    Join Date
    Jan 2002
    Location
    West Coast, USA
    Posts
    9,315
    Post Thanks / Like
    Likes (Given)
    607
    Likes (Received)
    6800

    Default

    For low quantities, I'll cut strips of softwood (lattice, etc.) to capture parts on the movable jaw side. Just crush them until the vise is about normally tight. With moderate cutting forces, these capture and retain parts firmly. Balsa will handle even highly irregular parts as a prototyping expedient.

    Just throw away the deformed bits after. Disposable plastic strips might also work, but the crushed cell structure of wood seems effective and the material isn't as slippery as most plastics.

    This was, of course, before lumber dealers started selling wood by the ounce.

    If you deform plastic with a high part in one setup, seems likely to me that a low part in the same pocket might move the next time around if you try to make permanent plastic jaws. Stay below the deformation limit (high durometer rubber??) and you might have enough clamping force for somewhat permanent jaws and variable thickness parts.

    Best if you can have most of the cutting force working against the fixed jaw.

  8. Likes DouglasJRizzo liked this post
  9. #6
    Join Date
    Feb 2007
    Location
    St. George, Utah
    Posts
    1,429
    Post Thanks / Like
    Likes (Given)
    948
    Likes (Received)
    997

    Default

    A lot of plastics are slippery. I prefer leather, and just on the moving jaw of course.

  10. #7
    Join Date
    May 2005
    Location
    AZ
    Posts
    2,544
    Post Thanks / Like
    Likes (Given)
    260
    Likes (Received)
    868

    Default

    For a slightly different approach: I have frequently used a business card between the movable vise jaw and a stack of "identical" parts being held in the vise. It can accommodate a few thousandths of differential compression between parts in a vertical stack, or lined up next to each other between the jaws. Fairly good frictional properties as well.

    If you go through enough mergers and acquisition activity in the places where you work, you usually have enough defunct business cards for every clamping situation. ;-)

  11. Likes TDegenhart, Mark Rand, reggie_obe, 52 Ford liked this post
  12. #8
    Join Date
    Mar 2011
    Location
    Geneva Illinois USA
    Posts
    6,631
    Post Thanks / Like
    Likes (Given)
    2974
    Likes (Received)
    2664

    Default

    high durometer urethane rubber.

    Tom

  13. Likes Bobw liked this post
  14. #9
    Join Date
    Sep 2015
    Country
    UNITED STATES
    State/Province
    Ohio
    Posts
    1,855
    Post Thanks / Like
    Likes (Given)
    1215
    Likes (Received)
    1992

    Default

    I use a strip of Teflon.

  15. #10
    Join Date
    Aug 2007
    Country
    UNITED STATES
    State/Province
    Idaho
    Posts
    2,588
    Post Thanks / Like
    Likes (Given)
    1115
    Likes (Received)
    1433

    Default

    I have had good luck using a keywat cutter to cut a slot in the live aluminum soft jaw and inserting a 3/16 x 3/16 strip of nylon full width of the jaw that sticks out about .02 farther than the aluminum for cutting harder parts and square o-ring material for real soft parts

  16. Likes AckshunW liked this post
  17. #11
    Join Date
    Mar 2019
    Country
    UNITED KINGDOM
    Posts
    295
    Post Thanks / Like
    Likes (Given)
    2
    Likes (Received)
    75

    Default

    Could you machine a tapered location to negate any deviation in the parts? Maybe like 2-5 degrees? Then use aluminium as the material and allow them to bed in the taper surface?

    Or use a hard fixed parallel jaw and a sprung loaded piece to take up any slack in parts?

  18. Likes 1yesca liked this post
  19. #12
    Join Date
    May 2017
    Country
    UNITED STATES
    State/Province
    Minnesota
    Posts
    2,118
    Post Thanks / Like
    Likes (Given)
    2897
    Likes (Received)
    1520

    Default

    I've done this sort of thing with aluminum or even steel jaws. Just cut the "A" side of the parts from a strip the length of the jaws, flip it over as one piece for the "B" side. Parts are cut with the same tool at the same offset, size difference is almost zero within a strip.

  20. Likes kustomizer liked this post
  21. #13
    Join Date
    Oct 2005
    Country
    CANADA
    State/Province
    Ontario
    Posts
    1,706
    Post Thanks / Like
    Likes (Given)
    562
    Likes (Received)
    665

    Default

    I'd think delrin or some other plastic would deform but would it return to it's original size so the next run of parts are held properly?

    I think Tom in post #8 might be on the right track. I just made some isolation mounts from 80 duro urethane and that is pretty solid, something a little stiffer would work I'm sure.

    edit: I see that was mentioned in post #2...

  22. #14
    Join Date
    Jun 2001
    Location
    downhill from Twain\'s study outside Elmira, NY
    Posts
    11,492
    Post Thanks / Like
    Likes (Given)
    4372
    Likes (Received)
    4104

    Default

    If most of the part is supported in the pockets in the metal fixed jaw, or even just against the fixed jaw, i have use the following materials for various ops:

    (You did say cutting forces are minimal)

    thick pape/cardstock
    cardboard (the kind on the back of notepads, not corrugated)
    Wood, just like PeteM describes.
    old flat leather belting
    Baler belting form Central Tractor (this does not work well for small parts as it tends to try to push them up)

    That said, when such things are necessary, i'm usually trying to hold 3 or 4 parts, not 10.

    smt

  23. #15
    Join Date
    May 2006
    Location
    Illinois
    Posts
    291
    Post Thanks / Like
    Likes (Given)
    105
    Likes (Received)
    57

    Default

    Thanks for all the feedback. Excellent ideas.

    I'll start with the Delrin since I have it on hand and see how it goes. Making the movable jaw modular will allow me to change it if needed.actuator-arm-maching-assembly.jpgactuator-arm.jpg

    Here's a couple pics of the setup and the part. Width of the part is 0.250 with a length of 1.61.

    Thanks again.
    gm.

  24. #16
    Join Date
    Aug 2007
    Country
    UNITED STATES
    State/Province
    Idaho
    Posts
    2,588
    Post Thanks / Like
    Likes (Given)
    1115
    Likes (Received)
    1433

    Default

    Quote Originally Posted by gmoushon View Post
    Thanks for all the feedback. Excellent ideas.

    I'll start with the Delrin since I have it on hand and see how it goes. Making the movable jaw modular will allow me to change it if needed.actuator-arm-maching-assembly.jpgactuator-arm.jpg

    Here's a couple pics of the setup and the part. Width of the part is 0.250 with a length of 1.61.

    Thanks again.
    gm.
    I was thinking you had individual parts, in strips like that I would simply cut the soft jaws to match the profile, remove all the material I can while still leaving them connected until the last op then seperate them, I wouldn't put any plastic in therr at all

  25. Likes mhajicek liked this post
  26. #17
    Join Date
    Jun 2012
    Country
    UNITED STATES
    State/Province
    Michigan
    Posts
    14,236
    Post Thanks / Like
    Likes (Given)
    4852
    Likes (Received)
    5133

    Default

    With having a surface grinder you might grind verticle groves and put on a strip of electrical tape on both jaws.

  27. #18
    Join Date
    Jan 2005
    Country
    CANADA
    State/Province
    Saskatchewan
    Posts
    10,403
    Post Thanks / Like
    Likes (Given)
    1421
    Likes (Received)
    3825

    Default

    I'd try the Delrin, or UHMW and face it with a 'peel and stick' abrasive sheet. I use the stuff that comes in rolls for a 5 or 6" disk sander, not sure what else is handy to get.

  28. #19
    Join Date
    Jan 2005
    Location
    Victoria, Texas, USA
    Posts
    4,832
    Post Thanks / Like
    Likes (Given)
    3515
    Likes (Received)
    1373

    Default

    I use strips of roofing lead I put in between the back jaw and work piece. When it gets thin, fold it over and reuse.

  29. #20
    Join Date
    Aug 2007
    Country
    UNITED STATES
    State/Province
    Idaho
    Posts
    2,588
    Post Thanks / Like
    Likes (Given)
    1115
    Likes (Received)
    1433

    Default

    10's of thousands of these goofy little bastards have run through these same 6061 jaws over the years, 4 operations, we put in a new blank in the back, a 3rd op strip after being broken in half in the front. 4 separated parts go in the right vise for the final op.Push the green button, when it stops you flip the back strip 90 degrees so you can do the end work, put 4 more parts in the right vise,green button, Put a new blank in the back, the last 4 in the right vise, take the strip from the rear station, break it in half and load them into the front, start it all over again.Whatever wear is in the jaws is even and polished now so they make better parts now than they did when new.
    img_7440.jpg
    img_7441.jpg
    img_7443.jpg
    img_7444.jpg
    img_7445-1-.jpg

  30. Likes michiganbuck, mhajicek liked this post

Tags for this Thread

Bookmarks

Posting Permissions

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