identifying rubber type and lethal ( to the rubber) solvents

[Tmoose]

the bushing construction is like this.

https://www.polymax.co.uk/media/cat...b8d27136e95/k/p/kpsb-type-hexagonal-mount.jpg

~ 8"Ø. Inner and outer steel sleeves are ~ .15" thick. The rubber is about .25" thick, and well bonded to the inner sleeve.
My task is to remove the tough rubber without damaging the inner steel sleeve

I'm thinking of a burning test to ID the rubber material, to then select a solvent that will at least break the bond to the steel.


The TIER one manufacturer is likely going to claim the material is proprietary.
I ain't asking them because the terrible quality of some key dimensions makes the bushing useless. We sent them an actual bushing from the order of several dozens they shipped us for their evaluation.
And so far their responses based on their evaluation have been disgraceful.

 

[GrahamBennett]

Try standing some of the rubber in normal gasolene for a few hours. If the rubber becomes very soft and sticky, gasolene is your answer, if it doesn't then you need some other solvent.

http://www.over50schat.com

 

[Compositepro]

Burn out the rubber with a propane torch in a few minutes. If you are concerned about affecting the heat treatment of the inner sleeve, stuff-in some wet cotton. After the outer sleeve is off you can clean off the rest of the rubber with a razor knife and wire brush.

 

[3DDave]

Seems like a lot of work to get two pieces of steel tube. Are they special in some way?

 

[Tmoose]

Hi 3DDave,

We need to gently harvest the sleeve to confirm the dimensions and form of the inner sleeve with good accuracy and precision.

https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSESb1Rdldos13lRMB8l5rEdjhLHD0Fyzwmxg&usqp=CAU

The ID was dimensioned as Ø6.752" +.004/-.001".
Inexplicably The tier one supplier so far refuses to acknowledge Y14.5, Rule #1, also known as the “Individual Feature of Size Rule” (the Taylor Principle).
Per this rule, the maximum material condition of our diameter and tolerance creates a size and form boundary at 6.751”, meaning a 6.750” shaft must be able to fit together with the bushing. Our 3rd party inspection proves this is not the case, as the maximum inscribed cylinder is 6.722”.

 

[3DDave]

I'd go with a liquid nitrogen dip and then drill out most of the rubber - work quickly and be prepared to return it to the cold bath.

You might be able to press it out when frozen - the rubber should be in plenty of tension and ready to fracture. Don't hit it - just press.

This might work:

https://www.youtube.com/watch?v=ATZlj7SObrU

but try it first on something you don't like.