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PISTOL PETES WRECKED tt spec (crashed by dead beats who wont pay)

5racer

5racer

Well-Known Member
 
Jack Johnson said:
A little insight from an old fart:
I always preferred using 1020 DOM or 1026 CDS (which is actually pricier than moly) for the main cage due to their ductility.
Both are much "tougher" due to their malleability.
Its all about the point at which materials begin deforming, to the point at which they tear or ultimately fail.
Yes, moly has an ultimate tensile strength 10-20% higher than the low carbon steels, but its elongation properties are much lower than 1020 or 1026.
Yes, .15-.20% carbon content DOES make a difference in regards to toughness.
Look at it this way, landing on the roof at 100 mph is better with cro-moly IF it's a one or two hit crash.
Barrel rolling at 100 mph, with multiple roof impacts becomes troublesome with 4130 because it does not deform well without tearing. That deformation is analogous to a crumple zone in the front of your car, or the foot box tearing away in an open wheel racer.
Add in the effects improper, or lack of post weld treatment of medium carbon steels (4130) which STILL is rampant in today's age, and you have a recipe for disaster.
For the record, 4130 roll cages are NOT heat treated like a 4140 spindle may be, they are stress-relieved by either high frequency vibration methods or carefully applied post weld heating and cooling processes.
I remember talking to Bill Stroppe (yep, I'm THAT old!) at the Parker 400 right around the Rough Riders campaign.
There was alot of monkey see sh** going on then.
While I was stress relieving ALL of my 4130 weldments at 1075-1125 degrees in the dark of night with a rosebud torch, he had this cool "vibratory" platen that he welded his chassis on. Done. No heat needed. Just jostle the ATOMS (not molecules) around at the proper frequency while welding and presto!
Sorry I jumped off topic.
But seeing lay-mans talk improper materials tech is like fingernails on a chalk board.
C'mon guys. At least you have the internet.
I had to go to a library to learn.
Click to expand...

sprint cars are welded with that method of vibs all of them or they won't let you race and there has been good success with that method
 
dhjeepgeek

dhjeepgeek

Well-Known Member
 
Looks like it proves that it bends and rips. In that particular situation.
 
PeteRock

PeteRock

Well-Known Member
 
Its funny all these people say 4130 does not bends and breaks, well how do you think roll cages are made? By bending 4130. So its very very likely in a crash where the roll cage makes contact with the ground, there could be deformation of the tube without cracks or breaks, especially if its over a long section of tube.
 
Dave_G

Dave_G

Well-Known Member
 
I don't understand why someone selling a TT wouldn't put it through an escrow. Generate the contract, buyer places money into escrow, buyer test drives truck and if he wads it up escrow pays the seller according to the agreed upon contract and buyer trailers his wrecked POS home with him. Escrow is common for aircraft purchases so why not for race cars? 🤔 I put my latest aircraft purchase through an escrow and it only cost a couple of hundred bucks. It provides protections for both parties.
 
BBBBeans

BBBBeans

Well-Known Member
 
J BomBer said:
what part of the car was this
Click to expand...
This was part of the rear bumper.
We rolled the car at the Snore 250. It was a blind turn and got tagged by the next car coming through.
It was sketchy but we made it out safely.


It all depends on the Tubing wall thickness.
 
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