RS Motorsport :: Classic Speed Restored

Off to the shed to do some more seam welding (chassis rails). When I come to do the window and door openings how do you people suggest it is done? I do not have a TIG welder only a MIG. Am I best to just run a weld along the edge of the panel join or would it be better and stronger to use the spot weld drill to drill out some holes in one of the panel's lips then effectively plug weld them together?

Going to this extent for a tarmac rally car is perhaps not necessary but I want to do it for the experience anyway.

I would use the spot weld drill then plug weld the hole with the MIG
(If you seam weld the edge you will have trouble when fitting the rubbers)

Personnally I haven't bothered with this - I have stitch welded the chassis rails and suspension uprights. The weld in cage turret to turret will then provide so much more chassis stiffness than playing around with the window seams.

Use Oxy-Acetalene and stitch weld all the seams of the windows and doors

Chassis rail seam welding going well. Good penetration and only 2 holes (easy fixed). Old seam sealer is a pig...no doubt carcernagenic (sp).

I am doing the chassis rails, front suspension and possibly the window/door openings. Should I be putting seam welds along areas such as the bottom of the sills and any other area where panels meet??? Rally prep book dopesnt say to but I have read that other people have....

I had thought about gas welding Danny. I have never done it nor do I have the gear. Any of the Adelaide boys with gear wanna teach me and earn a carton or two???

I did the "if it's got a joint we welded it" approach

What's the general consensus.....after seam welding do you grind down/dress the welds or leave as they are? Mine are pretty nice looking

On the white car I left them as is, and ended up capturing dirt in the edges and now have a few rust dot stains appearing.

On the new shell I have linished back and seam sealed to hopefully prevent the above

Ta Paul. Was hoping to leave them but I guess it makes sense to clean them up

TIG Weld !!
basicly fuse the 2 edges together

as i said in the OP, I dont have TIG facilities or knowledge. Will be happy to learn TIG if somebody wants to lend me a TIG machine!

Im not sure seaming the exterior body panels on is a good idea, especially if you have a well built cage and its a tree dodger. the chassis stiffness should come from the cage tying the suspension points together, the rest can flop around as we are only trying to maintain suspension angles, not window aperture shape?
If seam welded all round, the inevitable repair is going to be horrendous. Imagine the mess removing a rear quarter after its been seam welded to the inner panels, all a-round the panel. I aknowledge in the monocoque structure the rear 1/4 supports the boot structure etc, but again, maintaining tailights geometries during cornering is overkill.

Your car and only my 1.3 pence worth

cheers,

JP

Yeah get what you're saying JP. This is a tarmac rally car but seeing as I will be driving a "tree dodger" is a good description

I dont think I would ever go to the hassle of welding all around the 1/4's. Looking over the car I think the appatures definitely. Probably the A-pillars. Not sure about along the bottom of the sills. I dont think I would consider any other areas.

Yesterday I had a go at MIG'ing the flange where the front chassis rail is spotted to the inner arch. I got a fairly good bead along the flange without blowing it away but realistically the I cannot see that it adds much. It was once described to me as putting both hands palm to palm and welding at the fingertips. Doesnt really stop the palms coming apart!

Glenn
I was discussing seam welding with a guy that has been building escort gravel cars for the last 30+ years and he advised me against fully welding screen openings. He suggested plug welds approx. 50mm apart. Run a spot weld drill bit through the outer,plug weld and grind flush.
Easy to remove the damaged panel if the worst happens.
Make sure that you load it with fish oil or similar after you paint it,or you will have the burnt steel rusting.

Thanks for that. I am just taking a break now from the shed where I have just finished seam welding (1" weld, miss 1.5".....) the rear window opening. Decided to try to MIG and it appears to be doing a great job. No blown flanges (:oops:).

I got out a 5mm drill bit ready to grind it to a spot weld bit but after counting how many hundreds I would have to do on the car I got the MIG . I may revert if I start blowing holes.

On the rusting issue, I always cover up my welds afterwards with a liberal coating of KURUST (poked as far into seams as possible with a brush). That seems to be fine for places other than where there was old seam sealer remaining. In those spots, the seam sealer causes the welded metal to rust like mad!!!!!

Cup of tea finished.....time to get back to it.

The whole car has now been done. All window and door openings! Took ages but I think the depth of weld into the flange has made it worthwhile. Should have plenty of strength.

Now I am just trying to work out what to do with the rear firewall. Had some input previously from Roger M and have been looking at various pics on Turbospud. I think I will end up making some sort of a frame around the turrets then folding up some alloy sheet. Not sure how to stop it drumming though. Swag lines or maybe some kind of cross bracing between the turrets. I decided that filling the original panel might not look fantastic and I know I would regret it.

If the drumming bothers you on then firewall, stick 2 anti drumming pads on it on the boot side, works a treat,
if the extra weight bothers you for competition use, go to the toilet before each race to balance it out lol

Me not stupid!