pour your own bushings

[winchest]

can i melt wheels down without changing their characteristics? does anyone have any experience with this? i dont think it would be too difficult to make a simple mold but i could be wrong.

i have cut bushings from wheels and the bit gets hot and the wheels turn to liquid where the bit is cutting. When it hardens, it appears to be the same as before.

there is so much wasted material when you cut up a wheel.

[atomictiki]

An intriguing premise with possible promise. Of course
the downside is obviously wasted time and materials.

I have seen mentioned here before folks obtaining urethane
stock of different dimensions for lathing bushings. That may
be more cost effective for R & D than cutting up wheels.

Some Chemistry knowledge would help, too. I'd imagine that
liquification would alter the properties in some meaningful way.

Give it a shot and crank some out, there is no shortage of
willing Guinea Pigs waiting for another product to dissect.
I'm sure some pictures would elicit responses, too.

Tinkering is great, don't forget to skate.

[Longbord1]

well in a sense it isn't a chemical change because you are just liquifying it. its more of a physical change like chopping the wheel into little pieces.

i could be wrong though so don't take my word

[tomahawk]

no

most plastics (and urethane too) are thermoset polymers. Basically a chemical reaction takes place to join the -mers into polymers (ie make "plastic") and it's molded, and then gl re-melting it. It'll probably just burn and smell nasty as all hell.

[pithaya]

youd have to apply the heat in a way that it doesnt burn, maybe like a pot inside a pot of water or someother indirect heat.

CHopping the urethane into bits before will help it melt

[Ravn]

http://en.wikipedia.org/wiki/Polyurethane#Production

http://www.pslc.ws/macrog/uresyn.htm

[Sensei]

Mr. Wizzard ruled. He used to blow s_hit up.

[Aaron]

I have heard that Urethane fumes have very high toxicity. Be careful.

[winchest]

hey guys, thanks for the help

[mexifly]

Chaput is has taken big old wheels and cut out a bunch of bushings that way.

[Geezer-X]

Urethanes are 2-part polymers. There's a resin and a catalyst that are mixed, and the polymerization initiates a cure cycle. Once this reaction has occurred, it can't be reversed. If you melt cured urethane, the moleculer bonds are destroyed.

Normally, the 2 components are heated prior to mixing to promote good flow and leveling characteristics. This is why you'd hear about "hot pour" urethane as a selling point of wheels back in the day.

To make your own bushings, you'd need molds, which usually consist of a machined block of Teflon with cores the size of kingpins which are removable, a precision scale for mixing the urethane, a means of heating it, and finally, and most dificult, the knowledge of the black art of formulating urethanes to enhance rebound while holding the correct hardness, and having it be tough enough to endure the compression and shear forces a bushing undergoes.

I played with this a few years ago, and dismissed it after a few months of wasted teflon, urethane, and time.

That's why I bought every single remaining Tracker Stimulator on earth, and I'm not kidding.

[wombat boarder]

well in a sense it isn't a chemical change because you are just liquifying it. its more of a physical change like chopping the wheel into little pieces.

i could be wrong though so don't take my word

do pray, tell us what is a chemical reaction then?
seriously though, it wont be possible
if you really want to do this, youll need a lot of raw materials etc, and you may as well just buy bushings from people who know how to make em, and have been doing it for years