Mike, I spent a while looking into the best way and I know others have too. Lots of conversations about the same topic on the locostbuilders forum you'll find as well. I'll describe my conclusions (and then please everyone else feel free to disagree!):
It is important that when the bolt is tightened, the bracket hardens up tight onto the crush tube, and isn't left clamping the poly only. This ensures the tube stays fixed and the bush rotates around it.
My final assembly process was:
1) Clean all powder coat out of the wishbone sleeves (otherwise bushes are too tight). I used sandpaper wrapped around a bolt mounted in a drill. Worked a treat.
2) Fit poly bushes into wishbone and offer up to chassis.
3) Sand off from either end of either bush in order to make wishbone fit chassis - aim to leave the bush maybe 1mm longer than the chassis mount (i.e. a tight push fit). In my case I had to remove asymmetric amounts from the bushes which did concern me a bit with castor angles, but ho hum.
4) offer a crush tube up to the bush, and shorten if necessary to leave it about 1mm shorter than the bush (i.e. about the same as the chassis mount spacing)
5) grease up the crush tube good and proper (as John says I know some people have also made a grease reservoir in the bush. I didn't find it was necessary - ymmv.
6) press tube into bush then mount in chassis. Bolt up good and hard on to crush tube.
Done! Your wishbones now move smoothly around the crush tubes, just as the suspension gods intended (well, smoothly-ish - should then loosen up with use).
Anyone with different experiences?
Richard
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