How to approach this rear arch replacement

[tom2207]

Not quite sure what you are saying here! Are you saying that Fitzee’s stuff takes too long?

no , his is the only way to make money and get the thing done ,,, unlike some of the others
take a look at Wray Schlien , probably all spelt wrong , for exquisite work but way beyond normal folks budget , there are a lot of others too just his name sprung to mind , peter tomashini lazze etc etc etc

 

[Nick DV]

Ahh with you now Definitely agree with that

 

[Dell]

AHH to be fair Fitzey is the man!!

So having watched his video he said that usually the outer arch is worse condition than the inner arch.

So thinking open up the outer arch and inspect the inner cutting out the bad bits, patch the inner arch and line it up with the existing material for the inner arch and cross check it with the replacement outer arch. Then weld in the outer arch before plug welding the inner arch in place.

Saying this out loud I think Clecos or Skin pins are going to be needed for this job.

@Dell what's the difference between your everyday zinc spray and galvanize spray?

Cold galvanise spray is what it said on the Tin, not as good as hot galvanise dip but much better than Zinc, we tried a couple of years ago 2 bit of bare metal one cold galvanise one zinc and left them out in rain for a couple of weeks zinc going rusty galvanise just a bit around edges.

 

[Cosantoir]

Cold galvanise spray is what it said on the Tin, not as good as hot galvanise dip but much better than Zinc, we tried a couple of years ago 2 bit of bare metal one cold galvanise one zinc and left them out in rain for a couple of weeks zinc going rusty galvanise just a bit around edges.

And is it a spray or a brush on?

 

[Dcal]

And is it a spray or a brush on?

Brush on is much better because it will give a thicker layer.
You need good prep for cold galv whether brush or spray as it's mostly zinc and does not stick particularly well.
Blasting to white metal (ST3) is what is asked for but any good prep getting you to clean steel with a rough, grippy surface helps.
Galvafroid and Zinga are the two best known ones.

I use it between layers that are going to be plug or seam welded so ideal for between your inner and outer arch.
My thinking is, some will evaporate during welding but some will remain and the real advantage of a cold galv coating (like any galv process) is it will protect the steel around it that is not fully covered.

 

[droopsnoot]

When you were tidying up everything did you use seam sealer then or something like epoxy mastic? On the wheel side to finish?

Yes, I'll be grinding the welds back, some kind of paint to protect it, then seam sealer followed by a good coat of stonechip. If I can get to it, I put some sealer on the other side of the repair, failing that stick a load of cavity wax around that area.

 

[Dell]

And is it a spray or a brush on?

It’s spray on.

 

[tom2207]

Yes, I'll be grinding the welds back, some kind of paint to protect it, then seam sealer followed by a good coat of stonechip. If I can get to it, I put some sealer on the other side of the repair, failing that stick a load of cavity wax around that area.

or even better acf50.