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Martin Eastburn Martin Eastburn is offline
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Default Can you melt and cast polyethylene

Outrigger ground pads - sounds like you want some tough stuff
lifting up the crane with them. I would think you might squish them
out from under the feet. 1/2" steel plate would be nice, I see a
lot of large lam blocks or log cabin cutoffs.

I saw the guys here in town - they have some neat cranes! - They
use counter balance weights. They move them with the crane while
setting up - boom not extended... light enough to use tires...

I would think plate weights would be in the scrap line of yours.

Martin

On 11/12/2015 10:30 PM, Carl Ijames wrote:
"Ignoramus885" wrote in message
...

I wanted to make some "outrigger pads", which are square pads
something like 24x24x3" thick. I have some scrap polyethylene cutoffs
and I was wondering, if I just melt and cast them, do I lose any
possible assurance of strength?

i
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I've played a bit trying to melt very small pieces of PE, and I usually got
charring and smoke long before I got any kind of fluid state that I could
pour. I think there is a reason they use injection molding with PE and not
simple pouring - get it hot, pump it in so it doesn't need to have a very
low viscosity, and get it cooled before it can decompose. Guessing that you
only want two or four pads, I'd weld up a pan to use as the mold from mild
steel, maybe 1/4" thick or more on the bottom for decent temperature
uniformity and 1/8" or whatever on the sides with some angle for easy
release, and put it on a stove top with two or all four burners going. Put
in your chunks of PE and try to melt them in place, stirring as you go as
much as you can. Even if you don't get it all truly molten you might get
enough mixing to get a fairly cohesive mass. Then just turn off the
burners, cover it and let it cool slowly, and hope it doesn't crack too
badly. Do your pads have to be solid, or would high density foam work? You
can get some pretty thick foam from ULine for not that much $$.

-----
Regards,
Carl Ijames