I am about to get into the point where I am going to be replacing the floor pans in the 77 F250. I don't have my seats out or the carpet up yet, but they will need to be replaced. I am experienced in welding using my stick welder and my Mig. However, the mig does not have a gas kit on it and I feel like when i attempt butt welding, the flux core will blow through. I use my welders enough to justify upgrading my mig to one that will take gas. Would shielding gas be the way to do this repair?
Post Reply
1 of 1
Welders and Floor pans
1,287 Views |
9 Replies |
Last: 5 mo ago by BrazosDog02
Not an expert on the welding front, but I can stick to pieces of metal together.
Don't have any advice on what welder to use other than flux core mig is fine for most things as long as it doesn't need to be super clean after the weld.
Concerning replacing the floor pan, when you take out the old floor, undercut it by about 0.25" all around in relation to the patch panel. Drill a bunch of 3/16" holes around the edge of patch panel. Then rosette/plug weld the panel in. Way easier than butt welding. Then if you want a total weld seal, just do 4000 tack weld around the edge of the patch panel.
Just my two cents. Ignore me if you're more comfortable with a different strategy.
Don't have any advice on what welder to use other than flux core mig is fine for most things as long as it doesn't need to be super clean after the weld.
Concerning replacing the floor pan, when you take out the old floor, undercut it by about 0.25" all around in relation to the patch panel. Drill a bunch of 3/16" holes around the edge of patch panel. Then rosette/plug weld the panel in. Way easier than butt welding. Then if you want a total weld seal, just do 4000 tack weld around the edge of the patch panel.
Just my two cents. Ignore me if you're more comfortable with a different strategy.
Another option that may be easier - leave a "flange" on the existing pan, and use panel bond to secure the new pan in place. You could plug weld it if you really care but I don't think that's necessary. The right panel bond will be a quick fix
This will ultimately be a full restoration. I can flange the good pan and weld in the new but that leaves two pieces of metal and I feel like this would be prone to rust being exposed to elements. It certainly would be a neater and stronger patch. Butt welding will have a high chance of me burning through. Not sure the right way to do it. I guess I could flange weld and then use body seam sealer on the exposed pieces.
What do restoration shops do?
What do restoration shops do?
Calling ClassicDoug.
Not sure what the correct way to do it is, but I've seen people clean grind the back side of the flange and lay over with seam sealer.
Not sure what the correct way to do it is, but I've seen people clean grind the back side of the flange and lay over with seam sealer.
Hopefully Doug will chime in.
I'd cut the pan leaving room for a flange, lay a bead of body adhesive then screw the pan down until the adhesive sets. After dry, tape off the edges, pull out the screws, and paint seam sealer over the edges.
Plenty of factory body panels are held on with only body adhesive and no mechanical fasteners today. A floor pan would be fine. Just wouldn't be "factory original"
I'd cut the pan leaving room for a flange, lay a bead of body adhesive then screw the pan down until the adhesive sets. After dry, tape off the edges, pull out the screws, and paint seam sealer over the edges.
Plenty of factory body panels are held on with only body adhesive and no mechanical fasteners today. A floor pan would be fine. Just wouldn't be "factory original"
You know what else isn't factory original? The rust hole ventilation system. "Whatever blows your skirt up" takes on a whole other meaning.
I agree but would just overlap the new pans over the rails. Trimming the pan to allow a precise enough fit for butt welding sounds like a pain. Lap welds would be 10x easier.txyaloo said:
Another option that may be easier - leave a "flange" on the existing pan, and use panel bond to secure the new pan in place. You could plug weld it if you really care but I don't think that's necessary. The right panel bond will be a quick fix
Seam sealer. Tons of it in your truck from the factory. Stitch it with spots, clean and prime welds, apply seam sealer, paint.
This is the way I am leaning. Not because it's easier, but because I have the tools to create an actual flange. If I do it straight, it will look nearly factory, especially after seam sealer. I'll have a think on this. Butt joints are 'better' by all purists, but I have yet to see a true butt joint that doesn't look like ass. The more it's hidden, the assier it looks.
The guys that CAN make it look good are employed by good body shops. Suffice it to say, they have a little more practice and skill at that than I do.
The guys that CAN make it look good are employed by good body shops. Suffice it to say, they have a little more practice and skill at that than I do.
Featured Stories
See All
58:55
18h ago
8.9k
Ask Liucci: Offseason begins with a busy portal window & more
by Billy Liucci
35:26
15h ago
1.8k
Reed Report: Recapping a 'culture building' week for Bucky Ball
by Luke Evangelist
11:13
17h ago
1.4k
Dominguez will get his first taste of Lone Star Showdown on Saturday
by Luke Evangelist
whoop1995
Completed my Texas A&M bowl game ticket collection - 1944 orange bowl
in Billy Liucci's TexAgs Premium
51