1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.

Plastic Liners

Discussion in 'Steel, Hardware, & Handle Material' started by ToddR, Mar 7, 2019.

  1. ToddR

    ToddR Putterer, Tinkerer, Waster of Time Staff Member

    Likes Received:
    247
    Trophy Points:
    43
    Question about using recycled plastic for handle liners. My apologies up front because I'm pretty sure this was discussed some time ago. Also, my search function ever finds anything. I searched on "plastic" and got no hits. Something is up.

    Anyway, does anybody have some good ideas for upcycling plastic for handle liners? Also, tips on what types of plastic to use etc. I have it in my head that somebody suggested liquid laundry detergent bottles. I could be imagining it.

    Thanks in advance amigos. I know liner material wouldn't break the bank but I do get a big kick out of turning "junk" into usable things.
     
  2. FORGE

    FORGE Maker of the Year Best Knife

    Likes Received:
    289
    Trophy Points:
    63
    I would think that you would have a tough time to get most glues like epoxy to adhere to the plastic.
     
  3. dancom

    dancom Dust Maker Best Shop Tool

    Likes Received:
    949
    Trophy Points:
    113
    XenForo search is poor. OK, that might be an overstatement. LOL

    Many plastics have low surface energy. From experience I have found that epoxy will simply pop off of polypropylene. Also polyethylene is nearly impossible to get any adhesive to stick to. High surface energy plastics like ABS are ok with solvents (think plastic drain pipes and that horribly stinky goop). Polycarbonate can be bonded with solvent as well. There are ways around this like roughing and priming and heat treating. It really it depends on material and what you want to achieve, but test some out first.

    Dan
     
  4. Griff

    Griff Active Member

    Likes Received:
    136
    Trophy Points:
    43
    Yup learnt the hard way trying to epoxy up some G-10 to some colourful cutting boards that were on sale at Walmart I thought would make unique liners lol! It’s was part ignorance and part arrogance as the epoxy I use is 3M 08115 panel bond, used in collision repair for panels on cars in place of welding, so the shear strength is quite amazing...that said it didn’t like those cheap sheets and pulled right off haha! In the end you realize epoxy is a very picky partner and doesn’t lay down with any old cheap composite :D
     
  5. Mythtaken

    Mythtaken Staff Member CKM Staff

    Likes Received:
    245
    Trophy Points:
    63
    No, that would be an understatement. Forum search is notoriously bad.

    I agree with the others about the difficulty of getting a lot of recycled plastics to adhere. I like the idea, though, so it might bear some experimentation. I would think adding enough holes in the plastic would help, letting the sticky stuff bond the steel and scale material instead. The liner would just be the spam in the sandwich.
     
  6. Wishalot

    Wishalot New Member

    Likes Received:
    19
    Trophy Points:
    8
    Assuming we are talking about fixed blade knives here, can I ask why a liner is necessary for a knife. Newbie here.
     
  7. dancom

    dancom Dust Maker Best Shop Tool

    Likes Received:
    949
    Trophy Points:
    113
    Liners are not usually necessary. They are primarily used for aesthetics, contrasting with other materials, adding colour(s) to a handle etc.

    In odd cases liners can act to prevent galvanic action between dissimilar metals or thermal expansion buffering between dissimilar materials. Liners can also be used to aid in bonding materials of different surface energies. Some claim liners offer shock absorbing qualities, but I think that would depend on the material used.

    The sheets that are commonly sold as liner material are typically vulcanized cellulose fibre. It's commonly used for gaskets and in electrical manufacturing as an insulator. It is known as "fish paper" in the trades. At home I use it more for racing stripes on a knife.
     
    Wishalot likes this.
  8. Wishalot

    Wishalot New Member

    Likes Received:
    19
    Trophy Points:
    8
    Thanks, Dan. I have seen many knife handles that sure look great and while I envied the craftsmanship and work it took to create the look, I always wondered if it was for a practical purpose. Your response certainly answered the question. Again my thanks.
     
  9. John Noon

    John Noon Well-Known Member

    Likes Received:
    582
    Trophy Points:
    113
    The world of plastics they can be joined with
    Solvents
    Welding
    Mechanically

    For liners and such that I suspect will decide to take a hike some day I will drill very small holes in the material. This creates a nice spot for epoxy to fill which creates a mechanical hold on the material.
    the outer material will still need pins or bolts to hold everything in place
     

Share This Page