UHMW vs Polyurethane

[VinniE30]

I know there's plenty of vendors selling poly and one selling UHMW. Some that are on r3v. I'm looking for unbiased opinions and facts.

In what ways is UHMW better and worse than polyurethane? What about in an e30 used on both street and track for example?
I'm talking about engine/transmission/diff bushings and also subframe, RTAB, etc. Which is more fit for which application?

Where would UHMW fit into this chart from AKG's site? I've felt it and it feels completely solid and couldn't move it whatsoever so I guess it's like delrin hardness. But what is the advantage of UHMW over other materials of about the same hardness like 75D poly or just solid aluminum?
Lets talk about the condor speed shop ones for example.

[Varinn]

I deal with UHMW all the time through my work, but in a different aspect (machinery in a factory). I personally find that UHMW is a fairly dense, firm plastic. The problem with it is that it's very susceptible to scratches and gouging that eat away at the material quickly if it's used in a position where it will see lots of movement. It doesn't seem to deform much from impacts but I haven't actually grabbed a piece and repeatedly hammered on it to test, it does not rebound well from deformation. Major benefit of UHMW as I see it is price, it is significantly cheaper to purchase as a base material than poly or aluminum. Going from the list above, I'd probably rate UHMW somewhere around the Delrin. Above or below, I cannot say as I have not dealt with delrin before.

[e30Rooster]

They are very similar
UMHW

http://www.iplasticsupply.com/wp-content/uploads/2010/06/uhmwsheet.pdf

Delrin

http://www.iplasticsupply.com/wp-content/uploads/2010/06/PomaluxWestlake.pdf

you decide

[pwagon717]

I am running silence's motor and transmission mounts. They are really solid, and I was about to replace them as they do cause vibration. We decided just to keep them in as they are liveable.

[VinniE30]

Can anyone that's had both UHMW and poly bushings give some experiences?

[meengreene30]

Condor's motor mounts paired with E36 oem rubber trans mounts. Perfect combo imo for a daily

[cwatt]

Thread revival? Also interested in a poly/UHMW comparison from people who have driven both.

[SkiFree]

http://www.r3vlimited.com/board/showpost.php?p=3881423&postcount=9

You can have urethane as stiff as delrin/umhw/aluminum, all depends on the formulation. (80a is a typical street urethane choice, delrin/umhw is about 110-115a). Really just depends on how you want to car to feel and how you define it. People have been equally happy or unhappy with both.

and if you want some drama/nitty gritty.

http://www.r3vlimited.com/board/showthread.php?t=303678

[nando]

We use UHMW in industrial applications for its density and low coefficient of friction (close to Teflon).

For a bushing, I'd think Delrin would be superior due to its self lubrication properties. it's about as stiff but without the squeakiness.

both should hold up just fine. we're using it in one application as part of a support structure to erect a 6 million pound walking crane. it also seems to hold up to decades of exposure to maritime conditions, supporting process piping that isn't light and does in fact move quite a bit.

[crappycoco]

From what I've heard delrin isn't good for bushings because it softens up when it heats up. That's why polyurethane is widely used in motorsport applications. This also (supposedly) applies if you live in a hot climate.

Nevermind, brain thought UHMW is delrin. Silly guy.

[SkiFree]

UMHW and Delrin share many of the same characteristics.

Honestly though, there is way too much round-about information out there ... it'll make your head hurt and you won't end up with any clear answer.

[mitchlikesbikes]

i bought all condor stuff for my car because it's gotten good reviews and condor seems like a good company that is active racing e30s and takes care of their customers. i also don't care about ride quality, or i probably would have gone with something else.

[cwatt]

I was once told poly absorbs water and can swell and bind when used as a bushing. Can anyone comment on this?

[nando]

Absorb water? I don't think so.

[TRAK WDW]

From what I've heard delrin isn't good for bushings because it softens up when it heats up. That's why polyurethane is widely used in motorsport applications. This also (supposedly) applies if you live in a hot climate.

Nevermind, brain thought UHMW is delrin. Silly guy.

This is definitely NOT true. Most motorsport applications are either Delrin or Solid Al.

I'm running AKG 75D Delrin bushings front to rear on my e46 m3, which is also known as Acetal. Also, delrin engine, trans, shifter, clutch pedal, diff mounts on my e30. (soon to add AKG delrin subframe bushes).

Thread revival? Also interested in a poly/UHMW comparison from people who have driven both.

If your car is a DD, go with either poly (softer) or delrin (depending on your tolerance). Race car, go with Solid Al.