MWP":27l3w3kj said:
bajallama":27l3w3kj said:
MWP":27l3w3kj said:
I hope those adapter bolt things have been hardened!
If its just turned mild steel, i would be very worried.
Is there a reason they should be hardened? It's in pure shear from my understanding.
Its not in clamped shear (how calipers are normally mounted) as your two turned steel 90deb bolt things are taking *all* the load in a small area.
The more i think about it, the more incredibly unsafe i think they are!
Even if they were hardened, they will still fail... i have little doubt about that.
Make proper dog-bone adapters.
Easy to do and they will be safe.
Dog-bone's were my original plan but packaging will not allow them. The bolt spacing is exactly the same between the Lexus and Celica caliper.
So you're saying under a braking load the calipers will shear through two 14mm dia. areas of steel?
What is clamped shear? Do you mean the preload?
To stop an All-Trac at 1.25 G's, 1500 ft-lbs of Brake Torque is needed per front wheel.
(Cool little calculator =
http://www.jakelatham.com/radical/info/ ... tors.shtml )
I had calculated the Brake Torque from the Caliper Clamp force for these calipers and rotors and it came out to only ~850 ft-lbs (all dependent on pedal pressure), but for sake of argument lets go with the larger number.
To react that moment the point of shear is of question. I haven't gone out and measured it, but say its at about 3/4 to the rotor edge from the center.
Rotor is about 1' in diamter, 6" in radi. Caliper adapters are 4" from center.
3750 lbs force reacted at brackets.
Cold Rolled has a yield strength of 36,000 psi
Shear Strength = 36k * .6 = 21,600 psi
3750/2 = 1875 lbs force per adapter bolt thing
Shear Stress = F / A = 1875/.24 = 7812 psi
Factor of Safety = 21,600/7812 = 2.76
Let me know if any of my calculations are wrong and if I made some improper assumptions.