OK, I have 99% of the front driver side floor pan out. I think I will be lucky and not have to replace any of the braces there-hopefully. My question is this: what primers, fillers, paint do I need ato install the two pans on my 57 ford wagon? I am thinking of the following: Seam sealer Weld through primer bare metal primer and then paint Not sure what the first two are though or how to use them. Anything else? Thanks, Mike
A few different ways to skin a cat. but I will sand my floors before welding them. Much easier that way. Both sides. Apply a weld thru on inside of the weld joints Fit and weld em, dress welds. Prep the area then I will apply an epoxy. I will seam seal over the epoxy.
What he said ^^^! That's what I did on my '54. After patching all the holes I layed down a couple coats of epoxy then seam sealed......
It can be both, sorta. Caulk or preformed ribbons. Go with caulk. Several kinds. Even 2 part caulks. Go with whatever automotive grade fits the budget. Follow the instructions.
Seam sealer is what it sounds like, it seals seams. You use it on seams\lap joints that are spot welded or plug welded and not fully welded, it keeps water out. And like Anthony said always over epoxy, and filler goes over epoxy also.
I like 3M paintable seam sealer applied with a caulk gun and then smoothed with a bondo spreader. It dries harder than silicone but remains pliable. It doesn't sand very well so a tidy application is important.
My nephew gave me a tip when using seam sealer I thought was great. Now the factory wasn’t all that great at applying the seam sealer in a tidy fashion so what my nephew does is lay masking tape on both the sides of the seam and then applies the sealer. He smooths it out and then peels the tape for a very neat look.
OK, Thank you all for the info. If I am understanding correctly I should do things in this order: 1) Sand all metal edges that are going to be spot welded (top/bottom) so I have nice edges. Blasted previously to remove any rust obviously. And treated for flash rusting. 2) Apply a weld through primer to both sides of the metal. 3) Weld slowly (spot/****) 4) Spray an epoxy primer over everything top and bottom 5) Apply seam sealer and then re spray? I ***ume 4 and 5 can be reversed if need be. Does this all sound good? Mike
Here's a good idea, paint the floor bottoms in primer 1st. Just mark where welding has to be done and mask it, then just touch it up after. Unless you wanna do all that work over your head. If you have a rotisserie then disregard. And I said primer thinking red oxide resto look like a lot of cars are. I'm lazy like that, don't wanna work over my head any more than I have to.
I kinda like this style in a lot of places it is self leveling and looks factory. The caulking tube seam sealer has its place also.
The factory seam sealed over bare metal. One reason we fix so much rust on these old beaters. There are seam sealers designed for bare metal. Quickly collision repair. I prefer primer under it. I’ve also primed large panels before installing.
If “spot/plug “ welding a lap joint it’s a good idea to spray both surfaces with a weld through primer and then punch or drill hole where you want to plug weld. Clamp the panels together and take a drill bit the same size as the holes you made and grind it flat at the tip. Now chuck that bit up and hit the holes to remove the weld through primer so you’ll have clean metal to weld to.
The reason for the sealer is to keep water from soaking into the overlap gap. If a guy welds it the right way (**** welded), there is no overlap to hold water.
The OEMs lapped em. They also didn't build em to last forever. The overlap is a production ***ist. Their spot welders were high current and pretty bad***. In the 40s the overlaps were sprayed with an asphalt based sealant to prevent water from getting inside. Just a big swath of what we now call undercoating. Some plants/manufacturers sprayed the whole underside of the floor.
Thanks for the explenation. Id heard lap welding floor pans was a no no, but I see in some instances its still done, when so use weld through primer & seam sealer & you're good... Got it. Both sound better than my "stomp form" whatever s**** aluminum and screw em down with self tappers.
Update: first pan is done and set in place. I am going to cut the main pan down tomorrow and set it. Then I will see what else needs to be enlarged, patched etc. I am hoping to start welding things in after Christmas or early in Jan. I will come back here and ask more questions so stay tuned….
Yeah I know. I will have to fix that somehow with a patch piece. The problem I had was, I had no way to trace the out line on the new pan. So it was cut, trim, check, trim, check etc. I didn’t realize I had cut too much off until it was too late.
Get yourself a nice pair of left and right tin snips. I can get Wiss brand at my local Menards home improvement store. And pick up a sharp new scribe. Use the cutoff wheel to make the hole, then place the patch up to the hole and scribe it for an exact trim with your new snips. Try for a ZERO gap.
A suggestion, next time you post a picture, click on "Full size" Don't worry, it's a learning process!
***uming you require **** welds as that what it looks like you're shooting for, note that narrow patch pieces are all but impossible to weld as they blow away with the heat as quick as anything. I'd suggest about 1/2" width minimum. If that means taking some more off the repair panel then so be it. You can weld that on the bench = easier. Then do the aforementioned accurate scribbing etc, aiming for zero gap. Should help you make a nicer job, more easily, from where you are currently, if that's what you desire. Chris
Final cuts like that with a cut off wheel are almost impossible. Overlap a small amount and trace. Use aviation snips to make the final cut. if I need to add a piece to fix a bad cut, I make that piece much larger than needed. Then trim to fit. It’s easier than trying to weld small slivers of metal.
You can bridge those gaps with a copper backer. I'm sure the next panel, you'll fit in better after learning your lesson.
Going fwd, I suggest drilling a hole at the end of the parent metal, then cut your straight line between the holes. Rounded corners weld way easier and don't give that excess weld that shrinks more and warps the corner. Just an idea, fit is everything. Welding is fast n easy.
Small pieces of mig wire helps fill the gaps, burn it all together, jump around to let it cool, it does take some finesse. As mentioned, non steel backing works too.
I'd suggest about 1/2" width minimum. If that means taking some more off the repair panel then so be it. You can weld that on the bench = easier.----Thanks for the idea. Yeah I may have to cut some of the new metal away to make room for a small patch piece. Fortunately, there is a guy in my local club who used to make his own car bodies and I am going to have him come over and help me weld things up and give me instructions. Thank you all for the ideas and direction.
When I need a small filler I use thicker metal than the repaired area. And lower wire speed to keep the heat down. Good luck
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