Welding a carrier floor

[Lynn Eades]

Thank you guys. I will try to follow your accumulated advice. This floor is from a Canadian hull. It is 3mm thick.
As an aside, the NZ Bren has a new floor made from Corten. I am not working on that.
When i tried to weld the div plate from the NZ Bren, it kept cracking, when I used the mig. That was "mild steel" (nothing like mild!) from the ship "Bowen" built in 1901. I ended up using the stick welder, and I can't remember which rods.
Anyhow I'm guessing others have patched a Canadian carrier floor.

[Petr Brezina]

Hi Lynn, I used basic rods 7016 on my British carrier with pretty good results. No preheating, armoured plates to mild steel.
I was surprised how easy it went.

[Phil Waterman]

Originally Posted by Lynn Eades

Thank you guys. I will try to follow your accumulated advice. This floor is from a Canadian hull. It is 3mm thick.
......

Hi Lynn


3 MM seems thin, check my math guys that would be .11811 inches thick that's less than 1/8 of an inch. Floor plates in CMP cab are thicker than that.


I've welded 1/4 inch diamond plate very successfully with Mig welder using CO2 or CO2-Argon with a 110 volt machine. As suggested weld in short sections to prevent warping. If you can find an old brass kick plate I have had very very good luck using them as a heat sink behind the weld to prevent warping. Brass or copper are good because the weld won't stick to them. If you don't have brass plate I've been using scrap copper pipe just slit it and flatten it out.


Another good heat sink trick is wet toilet paper scrunch up and stuck to the steel about an inch from weld.


Before and after pictures of the repair would be interesting.


Cheers Phil

[David Herbert]

I agree with all of Phill's comments but copper works much better than brass because of its higher melting point.

I must admit I thought carrier floor was 6mm but have never cut into it to see.

David

[Lynn Eades]

Sorry guys, I was assuming 3mm. It is actually 4mm.

[RichardT10829]

Pretty much all been covered, I used mig with good argon shielding mix. Weld an inch then move along say 10" before starting the next inch of weld, the aim as already described is to minimise heat soak into the job.

to add another facet to the job, I stretch my welds on long runs such as this....so weld the inch but before it cools flatten the weld with a hammer (dolly will need to be on the other side) this stops the sheet being pulled as the weld shrinks as it cools, in essence you avoid the issues of the two sheets becoming miss aligned and you putting un necessary tension into the sheets.

its a biggie especially welding aluminium, or aircraft skins which are thinner, but personally I advocate irrespective of metal thickness you do it.

best of luck to you buddy.

[eddy8men]

i replaced quite a few patches on my T16 floor using normal mild steel plate and .8mm mig wire. i welded it normally in one run and had no problems.
the only time i got cracking of welds was doing short 1" welds on the 1/2" wading plates. it goes against what everyone else has said but i put it down to not enough heat transfer from the weld to the armour plate. i did a few large plate patches on the side armour with the mig turned up all the way and had no issues as i believe the original armour got hot and took longer to cool down helping to even things out.

[Stew Robertson]

The floor plate is 10 gauge and can be welded with mig leave a small gap and go at it
Spot it into place and stitch weld it 10 inches apart down the length way easy peasy