Chrome Moly vs Mild Steel Help!

Old 12-27-2008, 02:06 PM
  #1  
markadams
Member
JUNIOR BUILDER
Thread Starter
 
Join Date: Jun 2007
Location: Fort Mill SC
Posts: 69
Default Chrome Moly vs Mild Steel Help!

First off I would like to say this is the best forum I have ever seen. I have bought a couple things and posted a couple questions and have had a great time meeting nice people all over the place.

Now I know this topic has seen its share of postings, but I still can't decide, so I need your help. I am a high school auto tech teacher and I am trying to form a race team with about 10 of my best students (even though it is open to anyone who wants to work). I am using a BBC, transmission and rearend from a former drag car of mine, so it will never be real fast. Ok so I have a steel distributor that will sell me CM for less than DOM mild steel (about $1.00 per foot less), however we do not have a tig welder. We do have a bender and a notcher. I have a neighbor that will tig weld it for us for $25 per hour plus consumables. That will entail us to move the car a couple time back and fourth, which is really not a big problem. But for every little bracket I forget to install it will have to go back to him for welding...Or should I spend more money, have it be heavier, and less valuable, just to be able to controll the welding process. Approx. how long should each joint take him? I know TIG is a much slower process than MIG. 15 min. 30 min. any guesses? If I knew how far the money savings using the CM would take us I could make a better decision.

I am pretty sure I want to go with the CM, but that changes day to day. Thanks in advance and sorry if this is a re-post. Mark Adams
markadams is offline  
Old 12-27-2008, 07:46 PM
  #2  
kwkracing
Senior Member
RACING JUNKIE
 
Join Date: Dec 2004
Location: austin texas
Posts: 729
Default

okay, let me be the black sheep of this post. lol.


In your case i could go either way, if you feel firm you and your class can mig weld , i would build a mild steel car on a budget and everything could get done hands on by you and the students. I also do not know to what extent you are wanting to build a car, tube chassis, back half with cage or so forth.
If you are wanting to build a full tube chassis i would do cm and let your friend weld it up, a typical 1.250" tube,360 saddle should not take more than about 30 secs to run a tig weld around, but you have to factor in, getting situated to run the weld, under the car , inside, where you cant reach and on and on. if the fit is tight, factor the weld time is twice what a mig weld would be, but yes every main thing needs to be tig welded. I wouldnt worry about resale that much either unless its a full chassis car. just my 2 cents.
kwkracing is offline  
Old 12-27-2008, 08:11 PM
  #3  
zipper06
Senior Member
RACING JUNKIE
 
Join Date: Jan 2006
Location: La.
Posts: 2,890
Default

I'm with KW on ths one, you're not building a high dollar hard at it compitition race car. I would build a rec. tube base frame, and you can buy the whole kit for about $600.00 then use .134 wall MS, for the cage and all the bracing. This will put it all under your control in the shop and you can weld it. If you screw up on a bend or notching, you have control of it and can fix it.If you go to cromoly and take pieces to your friend and something does'nt fit then it becomes a run around. Besides if you're doing it for your students, they can learn every facet of the build when it's done in house. A rec. tube chassis will certify to 8.50 easy and to 7.50 with a few more bars, and your students can say we built it, not like if you sent it out to be welded and fitted. By the way i took auto shop 45 yrs. ago and got hooked on cars and racing since then.

They had a highschool build off with 2 highschools a couple yrs. ago, one school did exactly what you're talking about, they sent the chassis out and had a chassis shop build it the other school did everything them selves and the school that did everything themselves finished their car first, and not only did it run faster but when the high dollar tube car got finished it still got outrun, this was in eastern Tn.

JMO

Zip.
zipper06 is offline  
Old 12-27-2008, 08:33 PM
  #4  
hotrodharley
Senior Member
EXPERT BUILDER
 
Join Date: Dec 2002
Location: spring creek nv.
Posts: 328
Default

i agree 100% with Zip..do it yourself and enjoy the build and your kids will have more fun helping and be a lot proader of it and what they will be part of.i do everything myself and maybe everything isn't perfect sometimes as it would be from a pro shop but i can not say enough on how good it feels when i beat a pro built/high money car at a car show or at the track..i don't feel there will be a big differance in what you get for it between the C/M and M/S if they are nhra certified for same time..

build yourself and have fun..
hotrodharley is offline  
Old 12-27-2008, 09:25 PM
  #5  
markadams
Member
JUNIOR BUILDER
Thread Starter
 
Join Date: Jun 2007
Location: Fort Mill SC
Posts: 69
Default

As a matter of fact Zip, I saw two episodes of that show tonight on speed channel. It was called drag race high. Pretty cool. They built some very fast cars. My administration is not as supportative than those on TV, so we are left to work on the car after hours. It is going to be a full chassis car. We even have a mock up partially built just to see how everything is going to work. Too bad it was built with 1-1/2 .090 wall mild tubing, it came out pretty nice. We will use that for templates when we get the correct tubing. I am using a fresh 468 aluminum head BBC out of my retired race car. We have a 63 Corvette front and back shell to set over our chassis. It should end up being about 1500-2000 lbs lighter than my full framed S-10 Blazer was, so I'm pretty excited. If I go with the CM, the students will cut, fit, notch and bend all the tubes and I will MIG tack them in place, then over to the neighbor for final TIG. I don't know how to post pictures yet. Well thats the plan for now...Tomorrows another day! Keep those opinions coming it is really helping. Mark Adams
markadams is offline  
Old 12-27-2008, 10:59 PM
  #6  
zipper06
Senior Member
RACING JUNKIE
 
Join Date: Jan 2006
Location: La.
Posts: 2,890
Default

Hi Mark,

The reason i mentioned the rec. tube chassis is that they can be bought in any stage, for example i had ART build my Anglia chassis, and it cost me $1050.00 fully welded with mounts for the strut front end and a 4 link.
I didn't know that you already had a mock up for a tube chassis.
By the way you got a good body to start with. I would go to the expense of ordering the SFI specs. either 25.2 or 25.4 for $35.00 that way you won't have any surprises when you go to have the car teched, i think it has to be a double lower tube chassis to certify to 25.2, single tube for 25.4, i do know that my rec, tube chassis will not certify lower than 7.50, but i don't think i want to go faster than that in a 92" wheelbase car anyway. I do have a Miller tig, so i'll be useing cromoly for the cage. good luck and i hope the kids really enjoy the build.
Keep us up to date on how it's going, and i think theres a lot of people on here that has most of the answers to your questions, which i donot have for sure.

Zip.

Here's the web page for the specs.

http://www.sfifoundation.com/
zipper06 is offline  
Old 12-29-2008, 09:45 AM
  #7  
markadams
Member
JUNIOR BUILDER
Thread Starter
 
Join Date: Jun 2007
Location: Fort Mill SC
Posts: 69
Default

Bought the chrome moly this morning. Wish me luck guys. I'll keep you posted on the progress.
Thanks everyone!
markadams is offline  
Old 12-29-2008, 11:42 AM
  #8  
curtisreed
Senior Member
RACING JUNKIE
 
curtisreed's Avatar
 
Join Date: Feb 2004
Location: KIEFER, OK.
Posts: 1,311
Default

Originally Posted by markadams
Bought the chrome moly this morning. Wish me luck guys. I'll keep you posted on the progress.
Thanks everyone!
We want pics also. Good luck to you and your kids.

Curtis
curtisreed is offline  
Old 12-30-2008, 02:14 AM
  #9  
zipper06
Senior Member
RACING JUNKIE
 
Join Date: Jan 2006
Location: La.
Posts: 2,890
Default

Originally Posted by markadams
Bought the chrome moly this morning. Wish me luck guys. I'll keep you posted on the progress.
Thanks everyone!
I don't know how to post pictures yet,


I use www.picoodle.com./

upload the image, and copy and past the #1 forum to here and the image shows up.

Zip.
zipper06 is offline  
Old 12-30-2008, 06:04 AM
  #10  
markadams
Member
JUNIOR BUILDER
Thread Starter
 
Join Date: Jun 2007
Location: Fort Mill SC
Posts: 69
Default

Zip, I have a picture downloaded to picoodle, but don't understand "copy and paste #1 forum to here". I did click on copy on picoodle, but it will not allow me to paste it here. Please explain. Thanks, Mark Adams
markadams is offline  

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service