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JB
13th May 2005, 09:47 PM
I have a thin metal tray I use for paint stripping that I thought would make a good spark catcher when I was doing some welding. Earth was sitting on it, I dropped the welder, now I have a 5mm diameter hole in my tray. Der.:o How could i repair this hole?

Barry_White
13th May 2005, 11:32 PM
A mig welder or oxy welder or pop rivet a piece of thin metal over the hole.

JB
14th May 2005, 01:08 PM
I think I should have mentioned that the tray metal is about 0.5mm thick. Also the repair needs to be be a seal against liquids.

Ian007
14th May 2005, 01:19 PM
what sort of liquids?

what about a piece of metal that you silicone in place to made it water tight!

bsrlee
14th May 2005, 08:56 PM
Back the hole & surrounding metal with a big chunk of thick Aluminium or copper/brass. Then puddle a weld at the lowest amperage/voltage you welder is capable of. I've done 1.2mm with a stick welder, but its not easy & you end up with an ugly blob to grind down if it matters. MIG & TIG are easier to control than a stick welder, you could possibly braze a patch on with Oxy or a propane torch.

Otherwise, I'd recommend getting a new tray for paint stripping & keep the holey one for spark catching - it will save a lot of aggravation & hair pulling.

DavidG
14th May 2005, 09:05 PM
What sort of metal is the tray?
Could you :
Solder it?
Silver solder it?
Braze it?
Or just stick a blind pop rivet in it - if the hole is or can be made nice and round.

JB
14th May 2005, 09:19 PM
Thanks for the replies.

The liquids are paint stripper, water, meths, etc. A silicon patch may well work.

I don't think I could repair it with my stick welder. Too thin.
Tray is about 4' square, wasn't cheap, and they are not readily available. Don't want to buy another..

The tray is galvanised thin rolled steel, I think. Made by a plumber, the same material they use for weather cocks and the like.
I dunno if I could solder, silver solder or braze it. I know stuff-all about metal repairs, hence my query. I don't think silver solder would be strong enough. I do have a hand-held gas burner, but it doesn't seem to generate a lot of heat.
Hole is too big for a rivet.

Apologies if this is starting to sound like the old duet, "There's a hole in my bucket, dear Liza dear Liza"..."then fix it dear Henry dear Henry"..."But..." etc etc.

DavidG
14th May 2005, 09:38 PM
Flatten the area.
Cut a patch from a tin can.
Solder the patch in place using killed spirits as the flux.

JB
15th May 2005, 09:07 PM
Solder the patch in place using killed spirits as the flux.

Sounds handy. What sort of solder? What's killed spirits?
Thanks David.

DavidG
15th May 2005, 09:35 PM
Go to Bun..(cough splutter)..ngs and get some solder (50/50 or 60/40) and a small bottle of killed spirits from the plumbing section.
Some times they have small coils of pre fluxed solder but you still need killed spirits.

Clean the general area but don't take the gal off (tray and patch)

With a small brush, paint the area with killed spirits.

Heat and apply solder to each part separately and wipe with a cloth so as to leave a film of solder on each. (tinning)

Put the patch over the hole, tinned sides facing.

Gently heat and apply solder and some killed spirits, until the solder flows under the patch.

Be careful with the heat. You do NOT want to burn the gal off.

If in doubt use an old plumbers iron.


Killed spirits : Hydrochloric acid with as much zinc as can be dissolved in it.

JB
15th May 2005, 09:43 PM
Thanks mate.

DavidG
15th May 2005, 10:25 PM
Forgot.
When finished, wash well to get the remaining killed spirits off else it will rust.