Tube frame kit car

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This is why I started welding. It's been a huge learning experience because I've gotten to use so many new tools. I started with Flux-core, moved onto using gas, and now I'm getting ready to learn to TIG so I can weld up the a-arms. This is kit car assemblying via plans. This is the car I'm trying to assemble [ www.grabercars.com ]. I go into my progres a lot more in detail at the Forum there. New to this forum and just wanted to share this. It's been a long-term project, especially the welding part. The further I get along, the more I notice my first welds looking like junk and redoing them.
Reply:Not to knock your project down but that is a large liability you have going there. Especially learning to TIG and then welding A-arms. Wow. You kind of answered your own question by stating the first welds look like junk and you are re-doing them. Remember this is not a welding cart. What is the use of this vehicle. It is still carrying fragile cargo and needs to be safe.Sorry but I have seen one person get maimed in person when he "welded" up an ATV with a GSX-R engine in it and the frame broke a 50mph. Where it broke was right at his so called "weld". Good Luck.   T.J.www.tjsperformance.comDynasty 300 DXHTP 240HTP Microcut 380Hyperthem 85JD2 Hyd Bender and HF Hyd Ring Roller all in one =(Frankenbender)Bpt. Mill/DRO4' x 8' CNC Plasma TableInstagram: tjsperformanceYT: TJS Welding and Fabrication
Reply:Well, eek. I know it's important to weld this thing up strong. The end result is a street car, not planning on any HP past like 250. Trying to keep it as light as possible. I am trying to ensure my welds as much as I can. Does it really hurt to grind down welds and then run over the area again with a bead? What's the usual proceedure for fixing a bad weld? I've found my first welds probably didn't have enough amps because the bead was more sitting on top, rather than into the metal. I grind down until it is flush with the tubes then just run down where the joint is with another bead.I'll be practicing with the TIG too until I feel confident before I start on the a-arms. I'll have someone inspect them befote I put them on as well to be safe. Also, the frame will be re-inforced in the end with some sheetmetal, VHB tape bonded to it. I've also been trying lately to find the high-load bearing points and re-inforcing them with plates as well. The guy who designed the car actually lives near me, so he should be able to tell me how I am doing. Thanks for any tips.I had also kind of figuring this would be pretty forgiving due to the full circumference welds you get to do on tubing. Heck, I couldn't even beat off a tube with a hammer that was only tacked. I ended up having to cut through the tacks. Well, you definitely have me scared a little, I'll be going over all my welds an extra time. Thank you though, I do appreciate your concern. I definitely don't want to get killed over this.Last edited by kman0066; 04-18-2008 at 02:45 PM.
Reply:Originally Posted by kman0066Well, eek. I know it's important to weld this thing up strong. The end result is a street car, not planning on any HP past like 250. Trying to keep it as light as possible.
Reply:Actually, I would think doing it over with 4130 would be the least safest thing to suggest.  The whole issue of post heat treating / heat affected zone embrittlement, etc would be far more complicated.  If the chassis is mild steel then it's going to be the most forgiving because at least it should be fairly ductile.I think it's great that you want to start a project like that and have the guts to dive right in - most don't.  But, you need to be very confident of your welds first.  Everyone else's comments are right - that is no place to to be questioning the integrity of the welding!This project reminds me of the Roadster I built.  It was an obsolete model that Panoz produced from '89 - '95 and I got access to the jigs and built my own.  It is all 304 stainless tubing.  Here is a poor shot of the chassis:For more pics visit http://webpages.charter.net/jlbarnes/roadster
Reply:Originally Posted by TubularFabActually, I would think doing it over with 4130 would be the least safest thing to suggest.
Reply:If you haven't all ready, I'd look into an evening welding class at a local tech school. The instructor can give you some pointers on how you are doing and whether or not your welds are any good. Even if you are not enrolled, if you ask nice he may be able to bend test a couple of your welds and you would have some real solid feedback. All the tests I have done in class have passed so far but I wouldn't trust my welding skills yet on something this critical.Nice project BTW and good luck with it. Keep us posted on how its going.
Reply:Thanks for the comments. I'll look into signing up for a class. I definitely want to do this right. I'm definitely not too old for school, heh, never can be I suppose. I really had no idea there would be that much to this. Figured it was a fuse metal and smile process. Well maybe not that simple, but I definitely think I underestimated the need of the weld strength.BTW, the guy who designed it has been trying to talk me into a smaller motor, he's more concerned about total weight than the strength of the chassis, but maybe I should head his advice as well. Bigger numbers shure do look pretty though.I'm not new to cars at all, just the welding part. This is my first fabricating experience of something this scale though.How is working with stainless? I'd definitely like to do that one day maybe. Sure would look a lot nicer and last longer I'd imagine. For now though, I think I need to save my project, I have almost a year into this so far and I'd hate to throw it all away.I'll also look into as many ways as I can for testing out the frame before I get going down the road in it as well.Last edited by kman0066; 04-18-2008 at 07:48 PM.
Reply:Originally Posted by kman0066 I need to save my project, I have almost a year into this so far and I'd hate to throw it all away..