Suspension Question

[ammoace]

I was wondering why suspenions on R/C cars have a lower A-Arm but a turnbuckle for an upper arm? Why not have Ti Turnbuckles for upper and lower arms? Wouldn't this shave overall vehicle weight? Indy cars, full size ones, have a simular suspension in front. You could still attach the shocks to the steering knuckles. I'm sure this has been done but can't understand why it isn't more popular. Granted this would probably be less successful for off-road then on-road cars.
Jerry

[KIWIRCGUY]

The Tamiya Avante off roader had this type of suspension arm set up. It would be very hard to set up sort of like a Hongnor OB4. Everything has to be just right, cant tell just by looking, and anyway the Avante always fell to bits.

[ammoace]

I guess the weak spot would be the ball cups instead of the turnbuckles.
Jerry

[The Real Maxxter]

Not really, when you think about it, what's to stop them from putting a pivot ball on the end of a ti rod. I see some cool after market parts coming here. As for ball cups, you could always install captured ball ends.

[Grizzbob]

Actually, ammoace, you pretty much just described a pivot ball suspension, which a number of chassis are using now(like the FSR Bullet, Serpent Impulse, Yokomo GT-4, & I believe the Nitro TC3 will too). They do allow an incredible range & precision of the suspension's set up, but they're also more difficult to set just right. They definitely make set up boards(like Hudy's) a neccessity, & you have to check the set up much more often than the older designs, as when they're off, the car will handle horribly...... :)

[gubbs3]

I've seen some touring cars (aftermarket items) have a lower A-arm but two upper camber links, one for camber and one for caster. I could see how it might help to have a lower turnbuckle. This setup would be very tunable but you would have to have many setup tools. It might be a little more fragile than regular a-arms but the tuning aspect of it would be remarkable.

[ammoace]

Grizzbob,
I thought there had to be some cars doing this. I wouldn't think a non-race oriented car would have a suspension this "technical" but like some others have already said the suspension tuning capabilities would be endless. Toe-in, Caster, Camber, and maybe even change the width of the wheel base. If you wanted to run 200mm bodies add longer Ti Turnbuckles. And if for some reason you needed a narrower wheel base then get some shorter Ti Turnbuckles. For the oval racers they could have longer turnbuckles on the right side and shorter ones on the left. In theory this would give the car more left turn bias and shift the center of gravity to the "inside" of the chassis.
I still think the hardest part, other then tuning, would be hooking up the shocks.
If you haven't noticed I keep reffering to Titanium Turnbuckles because I don't think steel and aluminum turnbuckles could handle the amount of stress these would be under.
Captured ball links would be awesome. I can't beleive I overlooked them. I have a T-Maxx which has those things everywhere. You would think they would be on the top of the list of must haves for most any application.
I wonder if I could adapt this type of suspension to my stadium truck. Hmmmm. :D
Jerry

[ 06-02-2001: Message edited by: ammoace ]

[WhoKnowsWho]

You could easily attach the shock to the end of the captured ball links, doesn't the Ultima ST use that type of method in the back? Instead of attaching to the arm itself, it attaches to an extension of the outer hinge pin.

[ammoace]

WKW,
That would work well as long as it didn't interfer with the wheels and you could find a collar to slip into the lower shock mount to take out the slack between the screw and the shock mounting hole. But brass or aluminum tubing could be cut down and used for a "collar".
This is looking more and more feasable. I think it is time to take a look at my MRC truck to figure out if it possible to "test" fit this type of suspension.
Jerry