What are the bushes made from?

[Rik178m]

Is there different types of polyurethane? We have some at work and I'm considering using it to make the wishbone bushes but want to make sure its the right stuff.

[squbti]

all i know is that the bushes have to be flexible & not too hard so that you dont get too much stress on the welds but i´d also like to know exactly what kind they´re made of because i´ll also be making them myself at work.
cheers

[Bonzo]

Polyurethane is sold by it's shore rating

80 or 90 shore should be ok.

I have heard it said that this material can be difficult to machine.

One thing I would say, my Poly bushes were definately injection moulded.

Personally, I would not know as I have never tried to turn the stuff

Heres a linky to the correct grade

Polyurethane Bar

[flyerncle]

It has been mentioned that freezing makes it easier to machine.
It is very expensive and is it worth the effort when they can be purchased with the sleeves for about £90.
I am making my own and used UHMWPE,total cost about £30,including sleeves.

[RAYLEE29]

Hi, ive made my bushes from black delrin its probably harder than the poly bushes but i figured if some people use rose joints then a slightly harder bush should be ok

Quite happy if anyone wants to give me a valid reason why not.

I paid £15 for 1metre of delrin and £3.50 for the four 300mm peices of 19mm stainless from the scrappy

I have my own lathe so making them was easy for me (engineer 28yrs)
Ray

[flyerncle]

There is no valid reason "why not" ,we are building on a budget and you get the I made this factor as well.