Floor pan corrosion - advice please!

Hello all.

I've just started looking over my puma for the first time after picking it up a few weeks back. I've stripped out the interior to be greeted with the following:



Mostly surface rust without penetration or weakening the structure. On the drivers side there is a hole that you could poke a biro through but I'm sure if I gently cleared away some of the flakes a bratwurst would clear it without damage. Not good:



The same patch from underneath:



So, my question is - which of the following is the best approach?

1. Get it pro welded by a decent garage
2. do a DIY MIG repair on it
3. Weld in a brand new box section joining the sills for the rear mounts and turn it into a track car
4. Strip the car for parts and send it to the puma graveyard

Thoughts? Cheers in advance

Same problem on my car. I am going to save up and get it properly repaired, or get some training in welding and do it myself.

As Flying Scotsman says but if you're thinking of taking up welding with a MIG anyway now's the time to get some practice in. On most of the areas underneath the Puma that rust it's a seam between thick areas (a strengthener) and thin areas (floorpan or inner sill). The thick areas are usually salvageable as you can grind off the rust back to good metal. You'll probably find that if you do the work yourself that the seat mounts (with the thread in) will be salvageable after you've ground off the rotted floor above them. But now for a caveat, if the floors are bad what's the bottom of the sills like and the rear of the inner sills?
Barry

tuonokid said:

....if you're thinking of taking up welding with a MIG anyway now's the time to get some practice in

Click to expand...

I've done a teeny bit of welding and have a MIG setup so it's deffo an option.

tuonokid said:

On most of the areas underneath the Puma that rust it's a seam between thick areas (a strengthener) and thin areas (floorpan or inner sill). The thick areas are usually salvageable as you can grind off the rust back to good metal. You'll probably find that if you do the work yourself that the seat mounts (with the thread in) will be salvageable after you've ground off the rotted floor above them

Click to expand...

Spot on - that's the case here. The strengthener plate looks sound now I've got it back to metal.

tuonokid said:

But now for a caveat, if the floors are bad what's the bottom of the sills like and the rear of the inner sills?

Click to expand...

Surprisingly, the inner sills seem fine, I've had a good poke down with a torch through the access holes. There's a couple of bubbles on the outer sill but some surface treatment and cavity gunk will keep that under check.

Cheers for the info!

You're very welcome, enjoy saving another Puma.
Barry

A quick update. I found myself with a free weekend day so thought I'd have a go at my first welding job. I've played around with a welder before but only tarting around with garden tools etc. for this I used my ebay special MIG, a cheaply grinder and a big hammer.

As seems to be usual, when you chase the rust out of a teeny hole it becomes... Well, this:



Hmm. Oh well, in for a penny and all that. Quick cereal box template:



Transfer to 1.2mm mild steel - thicker than the factory floor but I figure it could use the extra strength. And I had some in the garage. Fold lines marked for massaging into shape with the vice and hammer.



A little bit of tickling with the lump hammer - AKA fine tuning - and it's an ok fit. It seemed like a pain as it not only has a selection of angles and bends but drops off in a couple of planes:



To welding. Taking it slow and moving around a bit to help the cooling process, I tacked and moved, tacked and moved then filled in with a series of interconnected tacks until I built up stitches and eventually runs. It was good fun if a little stinky - the flux cored wire, underseal and sound deadening made for a potent combo:



I butt welded from the top but checked penetration below (snigger) and it seemed ok to me:



I bashed the repair into submission with a very heavy hammer and it all was rock solid so I reckon it's probably ok.

Didn't take any more pictures as I forgot, but I finished it with primer then seam sealer top and bottom, then paint on top and underseal below.

The folks who actually do this sort of thing will probably be laughing at my efforts, but for my first go I thought it was alright - I've seen worse from backstreet garages in the past for sure

Well done!

I think it looks great, I'm no expert but it sure looks less corroded!

Yeah that looks great, i wish i could weld.....

On the drivers side there is a hole that you could poke a biro through but I'm sure if I gently cleared away some of the flakes a bratwurst would clear it without damage. Not good:

Click to expand...

:grin: :'(

Kizza said:

i welded up a project puma members car last weekend, spent about 10 hours in total sorting out about 8-9 patches of bad rust. he wants to stay anonymous though :lol:

Click to expand...

Are we allowed to guess?