Results 1 to 3 of 3

Thread: v carving and routing incised letters in plastic sheets

  1. #1
    Join Date
    Jun 2018
    Location
    Pennsauken, NJ
    Posts
    31

    Question v carving and routing incised letters in plastic sheets

    Hi all

    i've been playing around with doing some v-carving in left over plexiglass that i have around the shop. I do a lot of electrical signs and often have cut-offs that never seem to get used up. I'm considering making some "business cards" out of leftover 3/16" white plexiglass. As a test i got clipart of a ship and then put lettering above and below it. I kept the lettering as a bold gothic font since it was small.

    i did a test cut and after playing around a bit, one run came out great. then I ran another a few minutes later and the bit started to melt the plastic chips which stuck to the bit and ruined the cuts. The bit ( a 1/32" ball nose in this case) was so hot that it burnt my thumb when i took it out of the spindle motor to clean off the stuck on plastic.

    A small v bit worked well enough but it doesn't give the look I'm after for small lettering (say 0.3" tall) set into the plexiglass. Do I need to cut the feed rate waaaay down or are there better bits just for plastics? Maybe a small end mill instead of the ballnose? Or even an aluminum cutting bit perhaps? I don't have small enough endmills but can get some if that's better. Anyone have specific suggestions?

    i also tried the same design in serveral differet types of wood (pine, poplar and maple, plus plywood). In larger sizes (about 8" x 10") it all looked fine but when i got down to the small letters, the edges were always fuzzy. Anyone have suggestiosn for small lettering in wood as well. Again the text is as small as .3". i can go bigger but don't want it to be larger than a cell phone. I'm figuring that most business cards are tossed but soemthing that's cool looking might be kept, even if many people are going electronic for business cards.

    I can post the file (assuming that's allowed) if that would be helpful.

    Thanks!
    Last edited by Rocco.G; 09-12-2022 at 10:40 AM. Reason: Forgot to incoude something

  2. #2
    Join Date
    Mar 2013
    Location
    Memphis TN
    Posts
    983

    Default

    Melting plastic typically indicates the speeds are too slow and the RPM's are too high. Lower the RPM's to the minimum and increase the speed. The problem with small bits and plastic is the chips, which carry away the heat, aren't ejected efficiently. That leads to melting.
    ShopBot Details:
    2013 PRS Alpha 96x60x12
    4hp Spindle
    12" indexer
    Aspire
    Rhino
    Fusion 360
    Ferrari 360
    Prusa MK3S+

  3. #3
    Join Date
    Jun 2018
    Location
    Pennsauken, NJ
    Posts
    31

    Default

    Ah, just the opposite of what I would have done. i'll give it a try.

    Thanks!!!

Posting Permissions

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