Hi:

I really botched the lengths of my front upper control arms. They were supposed to be 8.75”, not the 11” jobbies I made. I do need to organize my notes a bit better…

Anyhow, my current arms currently use custom turned Delrin bushes and a ˝” studded rod end (in place of a ball joint). This rod end screws into a cro-mo threaded tube adaptor. I’m really not fond of the Delrin decision. Since I have to rebuilt the front arms anyway, my thoughts are to switch to ˝” rod ends for the pickups as well. Thing is, it is a bit pricy once the rod ends, the tube materials and the threaded tube adaptors are added up. I’m also not quite sure if I’d like the way it would look.

Does anyone have any pictures of there rod end control arms, preferably with the nosecone in situ?

--Thanks, Chris

F1 cars use them....... shouldnt look that crap!

atb

steve

ps - beware if you mount them vertically that side loadings of the bearings are approx 15% of the 'pull' loading values. F1 cars use them mounted 'flat' im told, but this restricts angular movement.

I already have the book sized brackets fully welded in place.

My main concern is that of the upper control arms. Rather than thread the rod end into the angled control arm--and just let the rod end adjust for the misalignment--I would thread it into tubes that are perpendicular to the chassis...then the anged arms would meet the the perpendicular tubes. Since the arms are so short, it may look a bit funny because most of the arm would not look too traditional. Aesthetics or not, this seems like the way to go.

pics anyone?

--Chris

I would be inclined to stick with the Delrin bushes. They will outlast the rod ends (even Teflon lined ones) by far and the arms will be much easier to make. The ride will be hars though.
Putting rod ends on the inner ends of the arm will only give you adjustment parallel to the axis of the two rod ends. If you wanted the rod ends there to allow castor adjustment you would need to make stackable side spacers or have a third (non spherical) rod end adjacent to the outer rod end/balljoint to accomodate the change to the arms shape.

Chris,

I've been thinking about this issue and what I would do and I think I would stick with the Delrin units. You already have the book brackets in place, you could cut them off and start over... but what a royal pain! Locating new brackets in the proper location would be more difficult than to just build new a-arms.

Whip up a nice strong MDF jig and start a-cutting and a-weldin'!

Can you tell me why you don't like the delrin units?

Also - something like this except with Heims?




Graber

[Edited on 8/25/04 by sgraber]

you can shorten the upper wishbone relatively easy with some sheet steel and keep the important (expensive) parts like the threaded center tube.
Cut off the section with the threaded center tube and weld a top,bottom front and end plate to it.
Weld this whole new front section onto the wishbone.
hope the drawing will explain it a little

Thanks for both the comments. The shortening method is certainly viable and may be hidden by the wheel. If I rebuilt using rod ends, Graber’s example is exactly what I had in mind. His are hidden though, mine would be hanging out in the open.

After thinking a bit about this, I think I’ll stick with the Delrin. When I speced the part to get CNCed, I made the Delrin flange literally fit exactly to the suspension pick up bracket. I now know it would be better to make it slightly smaller. This means the bush tube will need to be filed slightly.

Originally, I used the MDF jigs to build the arms. I now believe this is the wrong approach. The wood will always move slightly and actually begins to burn as the arm is fully welded. I think I have it figured out how I will built the metal jig and make sure nothing moves…at least I hope. If anyone is still interested, I’ll post updates as soon as I build them.

Again, many thanks.

--Chris