Anyone know of any good tube chassis welders who like to weld for cheap (aka case of beer and a sticker on the car)? I head up a student racing club on campus (see sig) and we’re looking for someone to TIG our race car chassis. The chassis is all jigged and tacked, it just needs to be finish welded.
We have a few people on the team who can lay down an ok-bead (mostly MIG) but no one seems competent enough to TIG it.
not knocking you, however–carneige mellon’s sae teams are light years ahead of other schools in terms of budget, donated items, etc. i know at upj, we had like a 3k budget and outdated shit to build an off road car. you guys get carbon fiber, chromoloy tubing, top of the line everything.
our team was made up of all engineers, and me-- an eng. lit/history major w/ an sae membership card. I was the only one on the entire team who could weld, understood how to wire the damn thing, and got the donated parts (briggs engine, dana rearend.)
w/ that said, why dont you guys atleast attempt to weld the damn thing. i know cmu has to have a tig welder and enough tubing to let you guys fuck up quite a few times. i know upj had welders, and they even had a dyno that i didnt know about until my last semester of college–or i would have found a way on it.
thats what these things are for-- for the engineering students to actually “do” it before they make drawings of how it should be done.
It’s easy to knock when looking at the situation from the outside. We’ve worked long and hard for everything we have. Personally, I’ve put thousands of hours into the organization (no joke) - and I can barely lay a tack. Why? Because we have to design and build the entire car from scratch - I don’t have time to also become a professional welder, I’m already trying becoming an engineer. Design-time alone takes about an entire semester - we CAD and iterate everything, stress analyze every component and do physical testing when possible - this takes a huge amount of time (I’m not even mention the organizational bullshit we go through daily). Plus we’re not born with this knowledge, everyone is learned this stuff as we go. The fact that we are able to get a car on the ground, from concept to conception, in about 6 months with a group of only 6-7 FULL-TIME, unpaid students at an extremely demanding university is nothing less than a miracle.
That said we have had a few really decent welders come in and out of the organization, when we have, we’ve used them. In the past two-years though less experienced members have MIG’d our chassis, our welds look “ok” but we know a professional or more experienced TIG welder could do much better (we’d had problems we chassis cracking, hence our broad appeal to pittspeed). Our analysis said this shouldn’t be happening, so the problem is with us. We have a TIG, in fact, we have one in our shop – that doesn’t mean we have someone who’s capable of laying a good, strong bead
In regards to funding, we’re always indebt. Aside from our garage space and electricity bill, the university doesn’t give us a single cent. Every dollar our team runs on is given by a sponsor we’ve had to secure and keep on the team. We know what it’s like to be a team running on a 3k budget; I’ve been around long enough to see it. Our budget is significantly larger now, but because put in the time to get it there.
Every single one of us has a ridiculously precarious schedule; I rarely sleep more then 5 hours a night. Save the “you’re privileged, work harder” speech for someone else, we bust our balls.
I mean seriously its like 10pm on a Saturday night and I’m on pittspeed. Damnnnnn I need a drink.
PS: back to the point, any bad-ass welders out there?
i would be interested. i was on pitt’s SAE team my senior year. will send PM
Life’s gonna get alot harder than that. Enjoy it now.
Pick up a TIG and quit your whining.
people should see what these cars are like!!! there are so many hours into these cars being built. the competition is very fierce every year where compete with schools from all over north america
For the few years at the Pittsburgh Vintage Gran Prix I helped run the SAE autox put on over by Phipps conservatory. I remember hearing from some of the CMU guys how bad it was to get funding. After seeing the work some of the students put into their cars it kinda pissed me off the schools couldn’t at least lift a finger to help them out. Good to hear things are going better now.
I usually give a donation to CMU each year (small, but something). If it’s possible to direct it towards you guys then I will!
Check out the website, there’s a paypal donate button on the front page down on the bottom left :bowrofl:
It takes a lot to get a sticker on the car, but we list all small donations on our website.
To put some closure to this thread:
Last Friday I organized a ‘weld off’, where each of our 3 “welders” were given two test pieces to weld, using the welding method of their choice. As a control I also had a professional welder weld two test pieces. After welding, I destructively tested the pieces in a tensile test machine I found hanging out in our Civil Engineering Department (this thing is a beast, big cast iron contraption from 1902).
As it turns out, our welds, although looking much uglier then a professional welders, were on the same level of strength. The interesting thing is that the professional welder’s pieces failed at the weld itself where as our tubes were failing at the heat effected regions surrounding the weld. Obviously we’re putting in too much heat and too much filler.
Still, we verified that our welds, all be it not the best, will work just as well as if we get someone from outside our group to do it.
Another interesting fact: the absolute strongest welds in the group were MIG.
So this weekend we started welding our chassis.
Thanks though to all who offered to give us a hand!
(if anyone is really interested in this test, I can upload some pictures/data)
Did the weld itself fail, or the material right next to the weld? Was the same welding rod material used for all of the welds?
I wouldn’t mind seeing the pictures.
x2
Here’s some Grade-A nerdery.
Before wasting tons of time telling me how we should have conducted this test, realize that this was a comparative test between our welders ONLY. Thus I would not use these results to draw any conclusions about which type of welder is better (MIG/TIG), etc.
Also, it would have been nice to perform a verity of different loading conditions etc, but this test was decided because we had all of the resources to perform the test available and it was quick.
Your welds are just fine from an engineering standpoint in that scenario. Have fun welding, it’s a wonderful learning experience and very satisfying to see two pieces of metal (or more) become one!
Good experiment. :bigthumb:
How are you determining that specimen 3 fails in bending?
Looks like you are doing all axial tests.
Welding is a fun hobby.
Get some spare metal, weld shit together and make stuff…who cares if it’s good, it’s practice and fun!
Just don’t burn yourself!
We saw locational bending stresses on #3 because the tubes were welded together slightly bent (1-3 degrees, you can notice it in the photos). So when the tube was pulled axially it was also bending as it tried to straighten out.
Those are all pretty close numbers, that’s encouraging. Did you do any hand calcs to see what theoretical failure is?
If you had time you could even model some welds in ANSYS to see what it gives you. And when the database becomes corrupt you can do a CDWRITE/CDREAD to fix it (that was intended for obi-1 :))
Yeah, you were aiming for obi-1 but hit both of us… 