Mot seam welding question

I'm a noob to welding so ill use all the wrong words before we start haha. My boot floor needs patching most of it seems Mint just under the back seats have started to go a bit. If I was to cut the rust out and plate over the top lay the metal on the top and seam underneath wouldn't have a seam would that fail an mot if near a structural point. Does it need to be seamed underneath or does the plate have to fit the hole and then but weld the two together with a seam.

If anybody understands lol.

it can overlap if thats what you mean, as long as its strong ,not sure i get what your saying are you talking about just laying it and welding from the top ,it wont be very pretty if you do that and will leave a space for water to sit i would do both sides but thats just me

dyte said:

it can overlap if thats what you mean, as long as its strong ,not sure i get what your saying are you talking about just laying it and welding from the top ,it wont be very pretty if you do that and will leave a space for water to sit i would do both sides but thats just me

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Yeh that's it laying and welding from the top. I suppose that's true though that unless it was undersealed it would cause more rot quickly. I will probably best fitting the metal in the holes and sealing it round.

I would cut it back to square it off then fabricate a new piece that sits flush then weld it in.

the repair must be as close to the o.e pannel as possible, i.e if its a solid pannel it must be repaired with a seam weld all the way round, you can only spot or stich weld a pannel if it came like that from the factory.

ideally cut a piece that fits in the hole perfectly and seam weld it, if you are going to overlap (easier to weld - hows your welding?) make sure its as flush to the original piece as poss, seam weld it, tidy it up, treat it (front and back) with rust treatment (fertan or similiar) then red oxide, then seam sealer and then some good underseal (shutz) underneath. I have had to do this on a truck a few years ago and there is absolutely no sign of corrosion whatsoever, be carefull with this method as it can create an area that can fill with moisture and rust through much quicker.

Also practice on a scrap piece 1st and make sure your happy with it before you tackle the disco.

brettguise said:

I'm a noob to welding so ill use all the wrong words before we start haha. My boot floor needs patching most of it seems Mint just under the back seats have started to go a bit. If I was to cut the rust out and plate over the top lay the metal on the top and seam underneath wouldn't have a seam would that fail an mot if near a structural point. Does it need to be seamed underneath or does the plate have to fit the hole and then but weld the two together with a seam.

If anybody understands lol.

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drill holes in top piece and fill holes with weld to lower piece filling holes ,brush over with seam sealer,google puddle welding

jamesmartin said:

drill holes in top piece and fill holes with weld to lower piece filling holes ,brush over with seam sealer,google puddle welding

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Seen that when I was having a look on mig-welding.co.uk, never heard of that method before but I thought it was quite interesting

the_wolf said:

Seen that when I was having a look on mig-welding.co.uk, never heard of that method before but I thought it was quite interesting

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:lol: How about a consumable insert ring welding process.

That just sounds kinky and perverted. I like it

the_wolf said:

That just sounds kinky and perverted. I like it

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Look it up........ It can be a fooker to do right

the_wolf said:

Seen that when I was having a look on mig-welding.co.uk, never heard of that method before but I thought it was quite interesting

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best way with large body panels ,obviously chassis is fully seem welded,but long lengths of seem welding on panels causes distortion

jamesmartin said:

best way with large body panels ,obviously chassis is fully seem welded,but long lengths of seem welding on panels causes distortion

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That is why body panels/floors/ wheel arches are lapped and spot welded.