Welder on board, power supply advice

[GrowleyMonster]

Originally Posted by Reefmagnet

For small jobs don't discount using oxygen and acetylene welding. It is very versatile and can be used for cutting and descaling, too. Probably not the best for stainless steel welding, though.

For mild steel, gas would be a very good option. You can get little "pony" bottles that fit nicely in a gas locker,which needs to be up on deck, btw. You need a can of flux and a coathanger for the fill material. And a good deal of practice at home, making gates and patio furniture and stuff. Its actually a lot of fun.



I have a 48v bank for propulsion and I can run a bead using a ground and stinger connected directly to the bank. Not for the faint of heart. I have only done this once, aboard my boat, just a proof of concept.



On a glass or wood boat, the biggest question is where will you weld, and not cause significant damage to the boat?


Aluminum welding requires a shielding gas. It is also kinda tricky, because it conducts heat much better than steel. Stainless CAN be mig welded without shielding gas, using special flux core wire, but I have never tried it. I believe there are rods designed for SS, too. Again, I have never done that.

[Offshore1960]

The small inverter welders work real well for stick and tig welding. I have a Miller inverter welder on my current tug. Its small about the size of a large pelican case and weighs about 25 lbs. Works great. Alot of shipyards are staring to use them too because they are portable.

[a64pilot]

Originally Posted by earthmover

I am finding this thread to be excellent. So here is a question from a newbie. Is galvanized steel easy to weld?

Best to grind off the galvanizing, and do not breathe the whiteish /yellowish smoke that is given off. I have before I knew better, and it will make you sick to your stomach, give you a headache no hangover can come close to, and you can taste it in your mouth too.
I did a lot of stupid things welding as a kid, like welding patches on a sand dredges outlet pipe in a Jon Boat in the water of course.

Got flashed bad and didn’t think all that much about it until about 1 AM at which point I was sure I was going to go blind.
I was completely self taught on welding on the farm, and it’s amazing I didn’t kill myself. This stuff can be dangerous, be careful.

[john61ct]

Welding prank video
http://digg.com/video/welding-prank

[MCOS]

For the emergency or once in a blue moon use, have you considered running a single wire to the excited on your alternator, disconnect the output wire, substitute the output wire with a cable to your stinger. You could use auto jumper cable, clamp negative to engine ground, the other end to your work, attach positive to the alternator output after disconnecting the output from your wiring, work end of the positive to our welding electrode, you can clamp it to a vice grip for small rod, 1/16 1/8 or 3/32 depending on your alternator output and what you are welding.

[Adelie]

Originally Posted by GrowleyMonster

For mild steel, gas would be a very good option. You can get little "pony" bottles that fit nicely in a gas locker,which needs to be up on deck, btw. You need a can of flux and a coathanger for the fill material. And a good deal of practice at home, making gates and patio furniture and stuff. Its actually a lot of fun.



I have a 48v bank for propulsion and I can run a bead using a ground and stinger connected directly to the bank. Not for the faint of heart. I have only done this once, aboard my boat, just a proof of concept.



On a glass or wood boat, the biggest question is where will you weld, and not cause significant damage to the boat?


Aluminum welding requires a shielding gas. It is also kinda tricky, because it conducts heat much better than steel. Stainless CAN be mig welded without shielding gas, using special flux core wire, but I have never tried it. I believe there are rods designed for SS, too. Again, I have never done that.

Skip the acetaleyne get a propane-oxygen torch, much easier to source fuel and you have it on board anyway. Trade off is it burns slightly cooler

[Adelie]

Originally Posted by MCOS

For the emergency or once in a blue moon use, have you considered running a single wire to the excited on your alternator, disconnect the output wire, substitute the output wire with a cable to your stinger. You could use auto jumper cable, clamp negative to engine ground, the other end to your work, attach positive to the alternator output after disconnecting the output from your wiring, work end of the positive to our welding electrode, you can clamp it to a vice grip for small rod, 1/16 1/8 or 3/32 depending on your alternator output and what you are welding.

I wouldn’t mess with the alternator, I’d hookup 2 12v batteries in series to get 24v and use that. There’s even a wirefeed gun called ReadyWelder that runs off of 2 batteries like this.

Ready Welder

[roland stockham]

Couple of points. For those running 2x6v house banks you can only get 12v. Same with the alternator. Most welders run 30-60v so although you may have enough current not shure how well the arc would run. Plus with no control it is going to be very rough. Not sure my welding technique be up to it. Looking to the future I also want to be able to do things like working on 1" tube for rails etc so want to be able to do a neat job. Will be much easier to do ifI can work onboard.
A safety issue. I was always told that if you lay acetylene bottles on their side they can develop hot spots and blow. Is this a myth? If not I don't think they should be onboard.

[john61ct]

Originally Posted by Adelie

Skip the acetaleyne get a propane-oxygen torch, much easier to source fuel and you have it on board anyway. Trade off is it burns slightly cooler

Works for structural aluminum, 1/4-1/2" ?

[rmlarson1098]

Originally Posted by Adelie

Skip the acetaleyne get a propane-oxygen torch, much easier to source fuel and you have it on board anyway. Trade off is it burns slightly cooler

That's true, should work ok welding with LP. I've only cut with it and it is slower indeed; takes more patience.
Whatever fuel you use with your oxygen, You've got to have patience (unless it's sheetmetal!) and pre-heat the hell out of it. The edges to be welded should be 'breaking down' or slightly melting - not just cherry red - when you start to add filler wire. If you try to weld it before the joint is slightly molten, you won't have decent fusion. Might as well use J-B Weld.
But the more we discus this the more I'm convinced gas welding is the bomb (pun intended) at least for occasional use. If I had a steel boat, I'd bring a small stick machine on board and figure out a way to make it work.

[topmast]

Long before inverters and high tech Got pretty good at gas welding and brazing so found it handy on board Some one asked about laying tanks down Well,, the acetylene is disolved in acetone. Gas comes off at the top of the tank .Just imagine using the tank on it's side and acetone fills the gauge, hose, tip .

[Reefmagnet]

Originally Posted by Adelie

Skip the acetaleyne get a propane-oxygen torch, much easier to source fuel and you have it on board anyway. Trade off is it burns slightly cooler

You cannot fusion weld with propane. You can only braze weld. This is because the gas produced by combustion contains too much water vapour which introduces hydrogen to the weld.

[Reefmagnet]

Originally Posted by topmast

Long before inverters and high tech Got pretty good at gas welding and brazing so found it handy on board Some one asked about laying tanks down Well,, the acetylene is disolved in acetone. Gas comes off at the top of the tank .Just imagine using the tank on it's side and acetone fills the gauge, hose, tip .

You can store the tanks any way you want, you just have to use them right side up for the very reason you stated. The reason for the acetone is to contain the acetylene and prevent the acetylene from going "boom" as it is a very volatile gas. Also, if you have ideas on having the cylinders mounted remotely, do not use pure copper tube. Acetylene can form explosive compounds when exposed to copper although, oddly enough, alloys containing up to 70% of the stuff are fine.

[Simi 60]

Have a sip 160 stick onboard
Used it a few times on 6mm stainless
Short welds I have just used it on inverter/batts (8x220) when I've had 80amps of solar punching in
Other times I fire up the 8kva genset

[Simi 60]

Originally Posted by Adelie

I wouldn’t mess with the alternator, I’d hookup 2 12v batteries in series to get 24v and use that. There’s even a wirefeed gun called ReadyWelder that runs off of 2 batteries like this.

Ready Welder

That'd rape the batteries.
Would they ever recover from that abuse?