67 evil eleanor

On clean metal, you will need to etch with something like phosphoric acid in order for the POR 15 to bond. Also if you plan to paint it, you need to spray some primer on when it just tacks up (feels sticky but does'nt stay on your finger), otherwise, after it cures, nothing likes to bond to it, and paint can flake off. I like using POR 15 but usually limit it to areas that are not seen like interior floor pans and in the door shell along the bottom (insted of seam seal) and had good results. On the bottom, a 2 part paint works great and will resist brake fluid. Remember that seam seal works two ways, it keeps water out, and it keeps water in. So be wise in its use. Heres a photo of butt and spot welds on a floorboard section that need replacment. The tranny tunnel was enlarged and the butts still need grinding. The rotisserie makes life easier.

mortman

Tig welding is a great option but vary expensive and time consuming. Those are the down sides, the ups, less heat distortion much stronger welds. the down sides are the reason most of us use a mig welder, some one mentioned using a cut off wheel to grind the welds down, good advice but i used a flap wheel, grinds and polishes at the same time last 4 times longer and cheaper in the long run and less dangerous.
good luck

SJs 66coupe

You know what I like about the forums....I can come here and read and learn a ton without even asking the question. :-)

A friend had told me to use rivets to hold in the floor pans but I was under the impression that butt welding was the way to go so I was trying to figure that out. Knowing overlap is ok helps everything make a lot more sense.

My only question is what do you use for seam sealer?

I am considering doing my floor pans soon so I have certainly printed out this thread for reference purposes.

Shawnb23

I used steel screws to pull the pan and frame rail together. Then I drilled holes in between the screws and did rossete welds in the holes. Then I welded the screws through to the Rails.

HGC

I thought this was one of the most informational posts I have ever seen on floor welding so I messaged JamesW and asked if it could somehow be added to the FAQ. This is a post worth keeping around.

CalStang65

When you talking about etching before applying POR-15, should I be using the "Metal Ready" product put out by the same people that put out POR-15, or is that just a waste of money? How much POR-15 did you end up using? A quart? More? Less. I'm looking at two full floor plans plus seat risers (I'll probably do top and bottom just to be safe) so I'm trying to get an idea how much I should pick up without over buying. Thanks for any insight you can provide . . .

67 evil eleanor

That should do it. POR does'nt like to stick on clean shiney metal and the acid (metal prep) will etch giving it a better surface to bond to. For me, I would rather use the acid as to leave some rust. As long as it has phorsphoric acid, it should work, their brand or some off the shelve. I would think a quart would be enough. Also have some plastic wrap ready to put under the lid of the POR can when you re-seal it. If you get it in the seam and put the lid back on, you will not get it back off. If using the POR, I'm not sure what else, if any on the interior of the car that needs to be seam sealed. Their are a couple of places in the trunk and under the car that will need it though. I let it flow into the cracks and have had good results. Just make sure you check under the car after to see if any has leaked thru. Also wear gloves, if not, and you get this stuff on your hands, you will wear if for a week or so.

CalStang65

Good call on the plastic wrap, I'm guessing that will save me a real headache. Now just so I'm clear: is there a need to paint on top of POR on the floor pans? Is it purely cosmetic? It sounds like a 2-part paint on the bottom of the car will help prevent crud buildup, but is this 2-part paint on top of a POR bottom coat or on its own? And does it change things that the floor pans I ordered are EDP coated? Do I etch on top of the EDP? Do I not need to POR on top of EDP? Or do I remove the EDP coat, etch, then POR?

Thanks again!

CalStang65

So it sounds like I'm a complete idiot and won't be using POR b/c the new pans are rust free. I'm going to use a self-etching epoxy primer, then seam seal, then paint. I will then use an undercoating on the bottom. I figure that should work pretty well.

Any thoughts on how to patch up the hole shown below?



I think that's the speedometer cable (I could be wrong), but that seems like an awfully easy way for water to kick up into the carpeting/car. Any thoughts on how to seal that up without screwing up the cable going through it? Is there a part that is missing?

Thanks again.

Cheers!

Progress update: Finished painting the interior-side of the doors and the rear quarter-panels. Put on the rearseat seatback upholstery, but it turns out I was sent the wrong seat-portion upholstery from the rear. It is literally 8 inches more narrow than the original. Be careful when ordering if you're trying to re-upholster.

mortman

Sure looks like something is missing, your speedo cable should be much higher in the dash so i doubt that's it, i just checked my 68 and that hole is not there. i would find out exactly what that is and re rout it to its appropriate place and patch that mother up.