my first welding (car) help

[djinuk]

Ok, i have a renault 5 gt turbo, and i also have a mig..


The boot was carpeted by previous owned and trapped water, this has damaged a few areas which will need to be plated up..
My question is should i be cutting the areas back to neat rectangles and then cut out some peices from sheet of the exact same size or should the repair bit slightly smaller than the hole or larger.

I hope this makes sence.

 

[rkde]

you will find it neater and easier if everything is straight and flat. butt joints will give you a good flush finish so i'd say cut them to neat shapes

 

[mike 109444]

Please take care. I don't know the renault 5, but I bet that's your petrol tank under the boot ?. Also if thoes are pipes, pics 2 and 4 they are probley vents from the petrol tank that vent fumes from the petrol tank. You have been creating sparks from an angle grinder? near this. If you expect to do more and welding then remove tank!. Best of luck sorting the rot (dam that salt gritting gerrr) Mike G

 

[rtbcomp]

you will find it neater and easier if everything is straight and flat. butt joints will give you a good flush finish so i'd say cut them to neat shapes

I agree, and somehow nice square shaped holes don't look as intimidating as horrible rusty ones!

 

[djinuk]

hey mike, appreciate your concern however on these the tanks under the rear seats and them things in the pics are purely wires, these a bit of welding i will need to do which ill have to remove the fuel tank filler neck to attack but ill be removing the tank when i tackle that.

ok guys, nice square holes it is thanks for the advice.

 

[tux]

The more exact the fit of the repair piece, the easier it will be to weld with thin metal. Even a 1mm gap between panels will encourage hole blowing, not impossible to deal with, but why make it difficult for yourself.

 

[PaulMcElhinney]

Have a look on the Paul Baker Custom Metalwork site. He did some work on a Renault 5 GT Turbo. You might find it informative.

Regards,

Paul.

 

[redhouse53]

yep, as everyone said, make the holes as uniform as poss, use fresh steel if possible, not recycled, use a sanding disc on a rubber pad on your grinder, not a grinding disc for removing paint on the edges around the hole (or a dremmel if space is tight)

When you cut the new panels, make sure they are as tight as possible, but they will still need room to expand a little, good luck.

 

[djinuk]

really apprecaite your advice guys, i was going to use a pretty dead flap disk on the grinder for preping the edges (removing paint, im going to begin with the easiest holes and see how i get on, if i imagine them i will slowly move onto the more difficult ones. I will update on how i get on.

 

[djinuk]

speant a bit of time tonight, removed the aux fuel tank and wont be refitting it.

Ground back some of the rust to see the full extent, i think i now have a clear idea of how i will tackle this however i have somthing far more worrying.. this rot, caused from all the mud and crap stuck behind the filler neck, its very tight for access and im really not sure how to make a panel and weld iit in well up there.. Im half tempted to get it back to fresh metal, por 15 it, then do what i know how to do best and fibreglass it (matt/resin) , that way i can make the shape correct and i will be able to rust proof it well.. thinking this would probably be a better option than making a hash job of welding in a patch only for water to get back in at it.

 

[droopsnoot]

I don't know the R5 that well, if those holes are within 18" of a suspension mounting point you have no choice but to weld them up.

 

[djinuk]

the renualt 5s run a very basic rear beam with torsion bars meaning they only mount to the chassis rails under the boot floor, the holes here will be welded, the part im looking at fibreglassing are right up above where the filler neck goes so non structual etc. Theres no physical strut on these you see that goes up into the wheel arch.

 

[jayrs]

djinuk, i seen that user name somewhere before, you on FT.com aint ya?


R5's are common for rot in all areas, i have to say fella, its a nice fast motor, but one of the worse ive worked on before, there so thin its unreal, so i would advise weld where you can as there not that strong even when there not rotton.

you got your work cut on on this one i have to say.
thought of getting a joggler tool for some of the replacement metal?