Repairing Rusted Floorboards

[hmills]

I removed the rubber floorboard lining and found that the place where the floorboard meets the side wall under the dash on both driver and passenger sides is rusted through. Probably because the windshield weatherstrip allowed water to seep in over the years. I have never done this before so I'm going to ask some basic questions. What is the best way to remove the rust (What tools and techniques do you use?). How do you prepare the metal to be patched/what are the basic steps to repair these holes? HMills

[jor]

There are a lot of good post and photos here on this subject but essetially you are going to have to cut out all of the rusted metal and weld in a patch. If you are not a welder (nor am I) you can do all of the prep work (cutting, grinding, sanding) and take it to a pro for the patch. Then you can finish it up with bondo and paint.
jor

[heep70]

jor is right, cut out the bad rust (rot). I just did my floors in my 80 Toy. I fabbed my own pans and puddle welded them in. Before I welded them I painted everything with POR15. Then after I puddle welded them I cleaned around the welds and repainted that with more POR15. I sealed the seams and next I will undercaot the areas.

[spartman]

Nice pics there heep.

[Jake11]

Good work you did on that one!!!

[hmills]

thanks guys. any favorite tools for cutting, grinding and removing rust?

[boots]

thanks guys. any favorite tools for cutting, grinding and removing rust?

I have not done it on my truck yet, but I soon will. I plan to just use a 4.5" grinder to cut the old rusted part out, then Im going to use the grinder ( or if I have one by the time I do this, a bandsaw to cut the patches out of.

[flyboy2610]

Best tool to cut out the rusted floorboards is a reciprocating saw with a 10TPI blade. It'll go through those fllorboards like a hot knife through butter.

[Sharkdance]

I respectfully dis-agree with using a recipricating saw to cut out floor boards.
While it will surely cut the steel very easily, the length of the blade makes it hard to controll the depth of the cut and you could accidentaly cut something else. Especialy if (for example) you are trying to only cut the floor pan out and leave the rear section of the cab mount in tact.

IMO, a 4 1/2" grinder with a cutting wheel attached does a much cleaner job. The cutting wheel will only sink less than two inches past the floor board and you can cut around the cab mount easier with it without cutting thru both parts at the same time.

I just did mine. It probably took longer than using a recipricating saw, but I was able to cut out only what I wanted to cut and save the rest.

http://www.fordification.com/forum/files/leftcut.jpg

http://www.fordification.com/forum/files/00035.jpg

[hmills]

I really appreciate the replies. Thanks for the photos. I guess I should go down to the salvage yard and cut out the floorboard of that red 71 F100 I found a couple of weeks ago if it's not rusted out and if the yard would let me do it. we'll see. Need to buy a angle grinder - would be nice if it were cordless.

[heep70]

I used a 4 1/2" grinder w/ a 4 1/2" x 1/8" wheel. Worked great.