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.

[squbti]

the reason not to use hard bushes is that there are alot of forces in all directions on the suspension so not only up & down but also forward & backwards & so if the bushes are too hard all that stress & force will go to the welds .
Cheers

[thwang]

raylee what speed do you turn them at i allso want to turn my own.
thwang

[onedayTM]

Hi there,
reading your reply on the bush material subject and would like to know what the UHMWPE material stands for and is it as good as poly bushes.
cheers
tony

[Bonzo]

Originally Posted by onedayTM

Hi there,
reading your reply on the bush material subject and would like to know what the UHMWPE material stands for and is it as good as poly bushes.
cheers
tony

Here you go Tony

A Bit of info & online shop

I must admit, I had to find out when I read that