Working With HDPE

Discussion in 'The Garage' started by Prototype4342, Nov 14, 2017 at 11:39 AM.

  1. Prototype4342

    Prototype4342 Long timer

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    I bought some cheap HDPE [cutting boards] to play around with the possibility of making a rally fairing type thing for my 690. I'm thinking of making a rough cut with a jigsaw with a fine tooth blade on it, then using my cheapo drill press with an end mill bit to clean things up. I know that heavy side loads on the drill press will shorten the life of the bearings, but I figure i can put pretty light side load on the bit to make cuts in the HDPE. Anyone worked with this material before and have tips?
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  2. Nodabs

    Nodabs Been here awhile

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    Use a lot of SFM and upsharp tooling. Polished flute HSS end mills work best. Coatings or any edge prep have a tendency to make the tool build up cutting temps on the cutting edge.
    Air blast helps.
    A drill press won't work, there isn't any rigidity, the tool will chatter. Maybe a router would work?
    #2
  3. GregDavidL

    GregDavidL Adventurer

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    A router will work. A router in a route table will work better. Move the router/material faster than you think you should, you want big shavings (cooler cutting temps).
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  4. Nodabs

    Nodabs Been here awhile

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    Not to get too geeky technical, but .008-.012" per tooth feed and climb milling works best. Chip thickness is your friend and climb milling produces less heat. Heat is the enemy here, too much at the cutting edge results in a melted gooey mess.
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  5. ericrat

    ericrat Long timer

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    The fine tooth blade may not clear chips fast enough, but you will figure that out.

    I expect that your drill press won't turn fast enough for HDPE.

    I would use a woodworking router and bit. I have a made a few things in HDPE with wood working tools without much trouble. It is messy.

    With a handheld router I would conventional cut then do a climb cut as a finishing pass.
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  6. gmk999

    gmk999 ____ as a Rotax

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    Jigsaw will heat up the material too much and it will most likely weld back up behind the cut. Router is much better with a up or down spiral cutter to remove material from the friction area.
    Heep the machine moving , Heat (friction) is the enemy, so a good guide to run the machine base against is far better then a bearing and or collet
    #6
  7. Prototype4342

    Prototype4342 Long timer

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    I guess I will play with some things then. I don't have a router currently but maybe this is an excuse to get one :lol3
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  8. nickguzzi

    nickguzzi Long timer

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    Echo the ^problems^ with jigsaws - it will work but you need to find the sweet spot of blade speed and rate of advance.

    We used a lot of hand tools to work it. For straight cuts, a hand plane is excellent. Sharp and finely set.
    #8
  9. Beezer

    Beezer Long timer

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    look on Craiglist.... always routers & tables there for cheap. its a great tool. you can do so much with it, but beware the router, it will eat yer lunch if it gets away from you
    #9
  10. tominboise

    tominboise Long timer

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    I have something like 6 or 8 routers in the garage. I don't like to change bits. As mentioned, pawn shops and craigslist are your friends.
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  11. shovelstrokeed

    shovelstrokeed Long timer

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    A sturdy bench with a couple of stops on top and a coping saw is all you really need. For straight cuts, one of those Japanese saws with a long, blade does a wonderful job. The power tools, when used with skill and the proper bits are pretty good but the key word is skill. Applies to the coping saw as well, of course but it is less likely to make a huge mistake, which is the trouble with most power tools.
    #11