identifying steel for tubing

[dgordner]

Is there any way of telling the difference between seamless mild steel and (chrome molley)? Spelling? I think we have a karter in our organization who took the kart that was made of mild steel and had it duplicated with chrome molley. (spelling). I am the tech official and am getting hammered by the other competitors to check the kart but I do not know what to look for.

[dcarr511]

If its supposed to be ERW ( ?? ) MS then look for the weld seem, DOM wont have that though. You could have it sonic checked or weigh it and compare the weight to another known MS Chassis.

If it is the same thickness as MS and painted, I dont know how to tell w/o causing at least a small amount of damage ...

If its not painted you can look for the grade markings on it ...

If this guy is just whoopin up on everyone else ... it could very well just be he is a better driver. Have a friend who went through that, won the Season Points his first year and missed the last 3 races ... he just out drove everyone .. regardless of who's cart he was in.

[bjuice]

don't know what kind of KART racing your speaking of ( go -karts,sprint karts etc...)...anyhow most of these kart classes have weight restrictions Minimums( Kart and Driver)..if this is the case..i do not see where CM vs MS would make any difference....Cm moly is a lighter and tougher metal

can you tell us where the competitiors think he is getting the edge over them if it was a cm chassis ?...just curious

[dgordner]

It is a Red Cross fund raiser race with the Mini-Indy karts. This particular team is all karters as i am myself. However, There are other teams who have their act together as well but can't touch them. We know for a fact that they took the kart and had it made in cm. It is a violation of the rules as the rules state the kart must be purchased through the Red Cross. Short of causing a serious problem, I am looking for a way to point out that I know what they did by inspecting the chassi. It is a fact that cm flexes better and can withstand more abuse that the other metal. I just wanted a way to prove it other than cause more trouble than need be. There are several people involved, including the kart shop that did the work. Everyone are friends of mine but I have to be the bad guy.

[jmarksdragster]

Maybe a hardness tester, I believe CM is harder than plain steel. Also how about wall thickness?

[zipper06]

Is there any way of telling the difference between seamless mild steel and (chrome molley)? Spelling? I think we have a karter in our organization who took the kart that was made of mild steel and had it duplicated with chrome molley. (spelling). I am the tech official and am getting hammered by the other competitors to check the kart but I do not know what to look for.

You have a tough problem, without cutting a piece of the tubing and having it annalized by a lab.
Both mild steel and dom (1010) will have evidence of a weld seem, the difference there is that DOM is draw over a mandrel after butt weld IE leaving no seem on the inside.
I've been a mechinest for 50 yrs. and the way we can tell is spark test it. By this i mean take a piece of mild steel and put it up to a grinding wheel. The mild steel will spark more red, while the crome molly will spark more to the white side. but you still need some of the material that the chassis is made from.

Zip.

[dgordner]

Thank you Zip for the info.

[Bubstr]

Been a while since I was involved in karting, but I thought mild steel went out in the 70s because you could use up two to three chassis in a season. The thing that made Chrome molly better was it's memory, but even at that on factory teams we changed them out a couple times in a summer. Even their memory isn't perfect. I'm not for Chrome molly for a lot of things, but in a cart, it would be a waste of money not to have it. The guys are right a piece of 1 1/8 .083 in mild or molly weighs the same. There is a hardness tester kind of a spring loaded center punch that records the hardness. Not sure of the name or the price. The only other thought, would be to make templates off several of the legal karts. It would be very hard to reproduce the bends on a different mandrel. Hopefully the maker held to good tolerances. Of course on mild steel a crash could change some measurements but it wouldn't change them symmetrical. The best way out and cheaper for all in the long run would be to supply a C/M kart.

I doubt this is the reason they are fast. We had our Karts for sale at the race at all times after competition. It went less engines and seat and seat hardware. We was always competitive with them the next week. That should tell you where to look for advantages. That don't mean they are illegal.

[dgordner]

Ya, I fully understand as I was in Karting for 25 years with my two boys. Now we are in Stock car circle track. Where my problem lies is that the karts are purchased from Midwestern Industeries in Ind. and sold to the racers through the red cross as a fund raiser. Then we take a weekend and race through the park of Williamsport Pa. The real problem is that this team has won for the last three years and the other teams can't touch them. I have been there on the winning side and suffered the same consiquences of being a winner. Everyone has a reason for you winning all the time. Bad thing is that this team shouldn't have had the chassi duplicated with c/m because the word is out. Me being the tech man is being pressured to do something about it. Friendships will be lost but through no fault of mine.

[Bubstr]

As tech inspector it is your job to get compliance, not impose penalties. I would go to them and tell them what you know and that you are being pressured into action, so don't come with the C/M chassis if they don't want to be found illegal. That can't be anymore fair of you. There should be no hard feelings that way. The bad part is if you have to invest in something to catch them,it is deducted from the charity proceeds. If you don't, the race could belly up and their would be no proceeds for charity. Being the tech guy is a thankless job. Where a dummy gets disqualified for rounding off a port with a ball hone and a guy that knows shot peening and acid etching can make any port he wants. I actually got tore down 26 times with a restricted Yamaha KT100. It was so far away from the good end of port tolerance that the tech guys shook their head. The jug was a throw away in the machine shop. Factory port way to off for an unrestricted engine. It made power about 2,000 RPM lower than everyone else but it was good power curve.

[dgordner]

Ya, I am going to let him know that I am aware of the chassi and request he correct the problem. Take it from there I guess.

[mcracecars]

from what I understand, are you saying...
these guys duplicated a mild steel chassis and built it in cm and are using the cm chassis?
they are running a lighter car (chassis) therefore winning a lot ?(cheating)

If that is the case, are the ms chassis required to be a certain thickness in material, say .120?
If so, all you need to do is get one of the nhra inspectors to come in with their sonic checker and inspect the thicness of all the tubes in the chassis.
If the tubes check out thinner, say .083 or .065, then it would be either thin wall mild steel, which would be illegal, or cm, which would be illegal, and you would need to bounce them out of the running.
If it is .120 , or whatever is requiered it could be ms or cm, in which case, I do not see any advantage in the cm as it all weighs the same.

You will most likely have to pay the inspector to come and check out the chassis, but you could get the other competitiors who are complaining to pony up the bread for this if they are suspecting cheating here.
Then it would be in the other guys court so to speak, if they want to subject the car to the inspection, or save face and not continue with the chassis....if they back out or refuse the inspection, it would tell me they are cheating.
also, these chassis from the red cross are most likely mig welded, if buddies is tig welded, which is kind of required for cm then it could be cm or ms, but it still would not be a chassis bought through the red cross.
I also would question why someone would go through the trouble to duplicate a chassis in the first place, unless there was some way to gain an advantage....
good luck here...

ed

[Bubstr]

Ed I can see the advantage. You basically use the chassis as it;s own suspension. It is it's own springs and shocks. The difference, even using the same wall thickness would be the same as making a leaf spring out of mild steel or a spring steel with a lot of carbon and tempered to retain it's memory. There is a ton of deflection in a kart frame. you can pick up a front wheel sometimes up to 8 inches before any other wheel comes off the ground. You control it with ride hight, wheel offset and seat and mounting points and just moving weight around.