Anyone who's following my ramblings will know that my quick 'fix it up and get it on the road' has turned me into the local factors best customer so when it became clear that I would need new suspension bushes I decided to make my own on the lathe to save a few pennies. The first problem was finding the polyurethane, this stuff ain't cheap and a 38mm bar costs £1 per cm and comes in a minimum length of 30cm, so before I've started I'm already down £30. The two middle anti-roll bushes are mouldings so I've had to buy them too...... another £30 gone, suddenly the £100-ish charged for a full set on Ebay doesn't seem quite so heavy.
Ok, so here's the raw materials, 90 shore Polyurethane bar, and stainless bar to make the liners from. I am limited in what I can buy locally, so the larger bar is mild steel unfortunately. The poly bar looks frosted because it is, it's been in the freezer in the hope of making it easier to cut.
After centring the poly bar I started machining it down to the right diameter, the first thing you notice is that polyurethane is a complete bitch to machine. The key word is resilience, if you haven't got your tool centred properly and very sharp the plastic just pushes it's way under the tool and you get a horrible finish.
When you get cutting you find that you are actually peeling back a sheet of poly rather than cutting a line of swarf.
After a fair bit of swearing, this is the result, a blank bush.
Did I mention this stuff doesn't machine well? That includes drilling, holding it in a three jaw chuck results in a triangular hole in the bush. To get round this I made up a holder for the bush from nylon, this one is double ended so I can hold a inner arm bush with one end and a anti-roll bar bush in the other.
You have to feed the drill through the bush veeeeeeeery slowly otherwise it snatches and rides up the bit, it's actually quicker to drill steel.
Making the liners is just standard turning with lots of centre drilling to keep the hole square.
The inner arm liner has a 14mm bore which is fine as I have a 14mm bit, the anti-roll bar liner is 16mm and has to be bored out as I can't find a bit in that diameter.
The results!
The bushes aren't the shiny items you would buy as they aren't moulded and the internal bubbles inherent in the material are exposed by the cutting.
Bushes and liners pressed into the suspension arm.
I'm pleased with the results, but even more glad that it's all over, this stuff isn't fun to work with and I've probably saved myself £20 over retail and lost an entire day in the process. On reflection the seemingly expensive kits aren't a bad solution if you want a poly bush kit on your car.
Rich
The Megajolt system is the only gucci gear on mine. I've got it all soldered up, just need to mount the pickup before I put the engine back in, though I think I may get it through the MOT on the dizzy and then concentrating on getting it sorted. I'll try and get the settings close(ish) before taking it to the local rolling road at Tipton St John, apparently the owners have quite a reputation with A series tuning.
Yes the bonnet was specifically developed for front mounted fueling systems and to add additional cooling in the engine bay with hotter running engines. It certainly too a while to fabricate. 2 months worth of evenings. Not that anyone seems to realize whats involved.