Welding ideas/tricks

[mk2-1jz]

I'm just about to start prepping the rear quarter panels on my 88 camry to cut out and weld in patch panels. The patches I bought cover the entire length of the wheel lip, that is rocker panel all the way down to the bottom of the bumper. I have a managable amount of welding and body work experience to tackle this myself, but my question is how do I go about cutting the old lip off and trimming the new patch panel to fit in the void. I'm debating on the proper technique, and it has to look good. My first option is to cut out the QP lip and try to trim the patch to fit exactly in the void, OR cut the QP and slightly bend the edge of the metal in that I just trimmed with a sheetmetal hammer and dolly to be able to weld the patch with an overlap. Does anyone have any suggestions or a preffered method to tackling this project?

Jamie

Here are the patches I'm talking about.

[ghettosled]

while i havent done body work like this, i have been told by friends that do this (because im dying to get a project car and do work like this) to NOT overlap the panels - butt them together. since this is fairly thin metal, watch the amount of heat you use as not to warp the metal.


*edit* i bet if you post this in the general discussion tab youll get many more responses.

[mk2-1jz]

Thanks for the suggestion. I know and have been told butt welding the new panel is the proper way to do it. The thing is that the panel has to line up exactly in the void, the problem with that is if you miss even as little as an 1/8 of an inch when you trim your new panel its makes your life difficult because you then have to fill the gap up with weld, its tricky and you often get a lot of blow by, even on a low temp, where the wire melts a hole inbetween the gap your trying to weld. The trick i want to know is how to trim the new panel to butt up perfectly with the metal on the car, so that i dont have to weld over a gap,

Jamie

[marc780]

There is a special tool made that is sort of like vice grips. You grab one edge of the metal to be welded and squash it with the special pliers and it makes a "step" in the sheet metal so you can weld it more or less flush.

[Grumpy_X]

Originally Posted by marc780

There is a special tool made that is sort of like vice grips. You grab one edge of the metal to be welded and squash it with the special pliers and it makes a "step" in the sheet metal so you can weld it more or less flush.

This is what you're talking about, a flange tool. Very handy indeed, but not necessary.
http://www.mytoolstore.com/astro/600pt.jpg
One side (upper) is a hole puncher, use to prep for plug weld.
Other side make a step in the sheet metal. Mostly use for lapped weld.

88camrycrazy - to better understand what you're trying to do, post a few pics of the damage you're trying to repair. Your post is a little vague, so seeing where you're at will help find the direction to where you want to be.
As a general rule, make the path (new metal) slightly larger. You can alway trim to fit with a grinder.

[mk2-1jz]

Well heres the extent of the damage....









Jamie

[Grumpy_X]

I'll do my best to explain while trying not to confuse too much. Its quite a bit of work, but not as hard as it sound. Set aside a weekend, give yourself plenty of time. Patience and determination will go a long way. Once you start, there's no turning back but going all the way through. A few tools you're gonna need;

- MIG welder, 110v will get it done, thin metal need little heat. Also welding helmet.
- Drill & spot weld drill bit
- Cut-off tool (for sheet metal trimming.
http://www.harborfreight.com/cpi/cta...emnumber=95028 or equivalence.)
- Safety equipment (safety goggle/face shield and glove)
- Vise grip (to held the patch in place while welding)
- Grinder (to clean the metal for welding)
- Hammer (to "persuade" sheet metal to line up/fit)
- Weld-thru primer (aerosol, corrosion protection for area behind the weld)
- Welding blanket (to keep spark off the interior, car on fire = bad)
Can also use cardboard & duct tape to seal off the interior, don't forget the door also.

These are bare minimum. Okay ready, here we go...


Look like you're gonna be using most of the patch panel. Rust is bad, you wanna get most if not all of it out. It already had some work done on it so I'm sure there's more underneath those body filler (bondo).

Depending what it look like behind the bumper this is a good place to make the cut (red line).


When cutting the rotten sheet metal off the car, slightly under cut it around (green line). Meaning leave a little bit more on the car, over lapping the new metal
Yellow dot is resistance weld (dimple), it need to be drill out to separate the skin (outer layer) and the structure (inner layer). Drilling only the outer layer and not all the way through. With this much rust, there may be only a few left. It take a special drill bit for this. http://www.harborfreight.com/cpi/cta...emnumber=95343 Drilling pilot hole will help keep the bit from walking.

After you get the old metal off, hold the new metal up to the car and trace the outline. Cut or grind off excess for a proper fit, double check the gap with door close. If the car has been in an accident, hammer the car to meet with the new metal. You may not need to drill hole for a plug weld in the wheel arches as there won't be much to weld on too.

Grind the metal about an inch back from the edge of both metal to be welded. Don't forget the flange on bottom of rocker panel. Spray the bare metal to be welded wtih weld-thru primer, especially the area where you can't get to after its welded.

When welding, first tack 'em in a few key places and double check the fit. Make a few more tack, spacing 3-4 inches apart, all the way around. Then weld about an inch at a time starting from every other tack. This will keep the heat down and distortion to a minimum.

Some grinding to clean up the weld, a little body filler to smooth it out. Throw on some primer and paint, she's good as new!


If you're still not sure or confuse, just ask or pm'ed me. Just remember, you can always cut a little more, but you can't uncut.

[mk2-1jz]

thanks a lot for your help, your putting me on the right track. I've got some more questions though, there in bubbles in the pic below.

[Flashmn]

I noticed your post, although I dont normally post in the camry section heres my 2 cents.

You cut the edge off with an angle grinder, but looking at the pic of the damage I'd leave that on and cut it from the car, you're probably gonna find more rust.

Get an inner fender for a camry or get it from another car thats close to the camry from so you can modify it to fit. Most bigger sedans come close. Making it from a straight sheet is not great.

If your rust damage goes down, replace it all, even if you have to add some from a straight sheet. Cut and weld as much as you can. Otherwise whats the point in doing the work, its gonna come back.

Yes those tacks are holding it down.

Easy way to make the mid fender seam is to use the flange tool and make step onto the car, then fit the replacement panel and tack it on. Its alot harder to weld a butt joint then a lap weld.
Remember to clean it with a wire brush tip and then put some weld thru primer there.

When you weld, start from the middle and make spots about 10cm apart, then let it cool down, then go again, and repeat, this will prevent the panel from warping due to heat.

Welders vicegrips, 3-4 should be atleast needed to hold it down.

Oh and the more power you have in your welder the more easier the job gets, cheap machines have very crude power settings. I have a mid price 220V mig in my garage and even thats kinda cranky to weld with. I've welded most of my corolla with it, though, I would prefer a 400V 3 phase machine.

I'm sure I missed some points, but dont hesitate to ask me in private message for details, I've done quite alot of body work.

OH forgot to say, invest in body solder, its alot better than bondo

[mk2-1jz]

body solder, you mean lead? I've heard that lead is much harder to finish than bondo, I use bondo gold, not the crap that people use to fill rust holes, the stuff thats meant to do the finishing. If its applied in this coats its a dream to sand. Ive done my share of body work too just not the quarters, the rest of the car is sanded and primed, I'm just waiting on this job, midterms=no time, so Im taking in as much info as I can before I go for it. Thanks a lot for your help

[Flashmn]

body solder, you mean lead? I've heard that lead is much harder to finish than bondo

Yes, and it is harder, but it gives you a result that lasts. It uses capillary force to fill up small pores welding leaves and prevents moisture from coming through from the other side. Bondo is like a sponge, it sucks moisture from the air into its pores.

Then when all is done, put rustproofing chemicals inside the body panels, that way you wont have to fix it every other year.

[Grumpy_X]

Sorry for the delay, work has been keeping me quite busy.


Flashmn has the right idea about the inner fender. See if you can buy it.

Flange tool is great if you got 'em, but not necessary. These metal are so thin that lap weld can be easily blend with a little bit of body filler. When you say gold bondo, are you talking about Evercoat Rage Gold? That stuff is great. A bit pricy, but well worth its weight in......gold.

After some grinding to clean up the weld, use wire wheel to clean oxidation off the weld bead. Filler don't stick very well to it. For the first coat of filler over weld, I usually do it in All-Metal. Its dense and very tough, help reinforce the joint.

[Flashmn]

It wont blend in with bondo, you can see it from the reflection when its done.

Flashmn has the right idea about the inner fender. See if you can buy it.

You can... just costs (alot) money at the dealership, see if you can get for example a Klokkerholm Volvo 240 inner fender, from the parts store you bought the fender you have pictured. Its big enough to modify to fit.

[mk2-1jz]

Ill check out the inner fender thing, its a good idea, I was wondering how i was going to fix that area. The bondo I use is this stuff, it is a bit more pricy, but I'm trying to fix the car, not put a band-aid on it, so its worth the money.

[Grumpy_X]

Originally Posted by Flashmn

It wont blend in with bondo, you can see it from the reflection when its done.

Believe me, you can. After you're done dressing the weld, tap it lightly with the hammer so its slightly low. Then smooth over with filler and viola, it never happen.

The shop switch to these a few years back, and I have no complain.