Quote:
Originally Posted by JamesCH95
I'm sorry, I should have been more explicit, my brain is not 100% in this caffeine-free day 
3/4"x0.35" square 4130 steel tubing would roughly maintain the weight of a 1"x0.065" aluminum square tube. The benefit is that 4130 steel still has a YS of around 70-80KSI when welded, whereas welded 6061 aluminum will be total garbage, around 8-10KSI. With further optimization a far more efficient chassis is possible if you use welded 4130 vs welded 6061 because the yield-strength:density ratio is roughly five times higher with welded 4130 compared to welded 6061. |
If a designer knows and understands the limits of a welded 6061 frame, this is not a downside. We've been running welded 6061 frames for years, and the one broken weld we had was just horrible, awful, horrible design. Please stop saying how awful welded 6061 is every chance you get. There are a lot of advantages to teams only having to stock primarily one type of aluminum (we still stock a lot fo 2024, 7068 and 7075 for shafts however).