Making a strong seam in galvanized sheet?

[Naio]

I'm making a thingy, and I thought one of you guys might be able to advise :B.

.It's for a small garden bed. I want to take some 6 or 8" galvanised flashing and make a ring. The seam needs to be strong enough to resist the outward pressure of around 200lbs dirt/plants/water.

I don't have a welder. (Can you even weld galvanized? Sounds toxic.).

I was going to use short bolts and nylock washers, but wonder if there is a better way. Ideas?

[BobsYourUncle]

Naio wrote:
I think I'll go with BYU's professional method upthread.

🙂

[Naio]

Mex, that sounds scary! But I have a morbid desire to know more details...


I wasn't planning to paint the galvanized. How long would u expect it to last if I don't?

Oh, gosh, I didn't think of this: It's for food plants. Is the metal safe?

[MEXICOWANDERER]

My giant carbon solder gun...

Around 1,100 watts. Touch tip of rod against lug. Arc not desirable. I use a big transformer controlled with a 120vac industrial foot switch. Part is held in a vise. Whole bench is other polarity. Heats 4/0 lugs WAY faster than a Turner torch in full song.

[MEXICOWANDERER]

Without a doubt IMHO that is by far the strongest and most secure way to do it. Hot galvanizing leaves a rough surface. If your sheet metal galvanizing is smooth as a baby's patoosh, it has been electro-galvanized. In that case if buried, I would apply two coats of Rust-O-Leum RED primer then a finish coat of whatever color you choose.

Rust-O-Leum RED makes a joke out of other metal primers as far as adhesion and durability. if you want this thing to last until 2109 AD coat the Rust-O-Leum with black pickup bed coating available at Wal-Mart.

[Naio]

I think I'll go with BYU's professional method upthread.

[TexasChaps]

MrWizard wrote:
the carbon rod, is for creating the arc aka electric torch
But it adds No filler material like a regular welding rod

Harbor freight sells clamp on spot welders pretty cheap
Used for home body work

But I think I would stick with drilling holes
A 3/16 hole and some number 10 machine screws aka bolts will be strong enough

yeh.. small screws or perhaps soft solder the thing..?

[MrWizard]

the carbon rod, is for creating the arc aka electric torch
But it adds No filler material like a regular welding rod

Harbor freight sells clamp on spot welders pretty cheap
Used for home body work

But I think I would stick with drilling holes
A 3/16 hole and some number 10 machine screws aka bolts will be strong enough

[Naio]

Mex: I solder my battery cables with a propane camp stove. Maybe I should move to mexico and learn to weld. What is the carbon rod for?

[MEXICOWANDERER]

Mexican spot welding:

12 volt battery.

8 gauge jumper cables

1/4" carbon rod (not the easiest thing to find)

Dark glasses

Also works great for soldering battery cables

[Dusty_R]

I do sheet metal fabrication, and spot weld a lot of it.

Dusty

[MEXICOWANDERER]

BYU
Is obviously an expert 🙂
Naio when working with sheet metal WEAR GLOVES! Very Important.
If you decide to go the hole drilling, nuts and bolts route. After doubling both ends use Vise Grips and clamp tight. Nut & bolt after drilling then do the same for each hole. Old Mr. "One Hand" here has to try and outwit struggles.

[MrWizard]

drill holes bolt it together

[fj12ryder]

MEXICOWANDERER wrote:
Stainless anything a waste of money. Galvanic protection. #10 sheet metal machine screws. Drill 3/16" hole. Use flat washers both sides. One screw per inch in lightweight sheet.

Stainless bolts that are going to be buried in wet soil are a good investment.

I use a bunch of stainless bolts, nuts, and washers to hold the two halves of my pool sand filter together. Been on there for over 15 years exposed to rain and pool chemicals and still work fine and are easily removed. No rust whatsoever. Some things are the way they are for a reason. Or is there a better way?

[fj12ryder]

agesilaus wrote:

fj12ryder wrote:
I think Trackrig has the right idea: 1-2 inch lap seam secured with pop rivets or stainless bolts, using washers to spread the stress.

Definitely no welding galvanizing, very toxic.

Just curious, how do you do that for a round hole/fitting?

I don't understand the question. Do what for a round hole/fitting?