Floor pans

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I have a 76 Chevy truck that was my grandfathers. The floorpans are trashed and need to be replaced as well as most of the under floor bracing. Has anyone posted pics of a similar project? Does anyone have a link to a site for this kind of project?
Reply:I don't have any picts, but I've done pans in a couple older work trucks over the years. JC Whitneys used to sell replacement pans for a lot of older vehicles. I used them a number of times. Often was a lot easier than trying to fab on up from scratch if the damage was moderately extensive and simple sheets wouldn't do. Building a complicated pan from scratch was very time consuming and usually wasn't a good option unless there was no other choice. Usually the braces underneath were in moderate shape and I didn't have to F with them. One or two times I just needed to replace a small section. I forget what we did the one time. The other I had a donor vehicle that had been wrecked in the rear, that we cut out a section from to use as a "patch" so that eliminated that issue.All the parts were cut out with zip wheels ( didn't have plasma at the time), sanded to remove undercoating and rust, and mig welded in with a small 110v mig with 75/25 gas and.023 wire. 90% were but welds with tight joints or very small lap joints, to keep from having areas under the floor that would trap water/dirt/road salt and destroy the work. If we did have to do laps, we'd weld both sides if possible. Most was welded from the top for simplicity..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I have the new pans for each side. I have the plasma cutter. I have never done anything like this and dont want to mess it up. i am alos going to have to replace the rocker panels but those are going to someone who really knows how to get them in and lined up correctly so the doors fit right.
Reply:I have done several floor pan replacements... I don't have any pics of what I've done though, before I had a camera. First and foremost just buy the pans and save yourself a TON of time.http://www.lmctruck.com/icatalog/cc/full.aspx?Page=26Strip everything out of the cab, seats, carpet, seatbelts... all of it, steering column too as it will be in the way.When you get the pans lay them in the cab and determine if they are large enough where you will cut out the rot and be working with good metal, if not replace the rot first until the perimeter of the pan is good metal.When you are down to good metal drill out all the spot welds in the area you will be cutting out.Lay the new pans down and mark the edges of where you will cut... this is where you have two choices. Either lay the new pan on the old, clamp it down and cut both to size at the same time, when I do this I hold the grinder wheel at an angle so you do have the full grinder wheel cut width to have to deal with. When you have cut the entire old pan out lay in the new one and start fitting it, lots more grinding time and sanding will be required.Once you are satisfied with the fit you need to prep for welding, and clean is the name of the game here. I like to blast the factory metal as the sand blasting gets down into the pits and really get the metal clean and ready to weld. Then I use a scotchbrite wheel to clean the black paint off the new pan all along where I will be welding, including the spot weld areas on the cross members. You also will need to drill holes in the new pan everywhere a spotweld was so you can plug weld it in all those places.After all the prep is done I like to shoot the overlapped  areas with weld through primer for extra rust protection. After laying the pan in the truck I start welding, I have an extra big clamp for holding my but welds even, if you don't a hammer and dolly will get them even all the way around, fit is critical with sheet metal. I am assuming mig welding is at your disposal, I like .023 wire, but can live with .030.I like to tack the entire perimeter, a tack about every 6" and then go and do all the spot welds, it helps to keep warping down if it has central stability. I use a hammer handle to hold the metal tight to the cross members while I plug weld them down.After that keep tacking slowly around the pan until you have a tack every 1", at that point I start welding between tacks jumping around from side to side and front to back. When it is all welded walk away and let it cool for a while, don't rush it. When it is cool bust out the grinder and smooth it all down and stand back and admire.I like to flood the cross members with paint and a wand for further corrosion protection and then paint everything top and bottom.
Reply:Floor pans aren't too hard honestly.  I just used 22 GA sheet metal instead of buying premade tubs.Also... you will want to grind the welds down, prime the whole area brush primer over the welded spots and then seam seal over that to prevent moisture issues.JoeMiller 140 Autoset (2010)Miller Syncrowave 250 (1996)