I want to weld some black pipe, about 3/4 or 1 inch to a steel 30 gallon
drum. What kind of a welder do I need to do this? I have seen some cheap
arc welders advertised but I have never welded (except a small amount of
brazing) and I have no idea what it will and will not do.
Also, how are they measuring the current? Obviously you can't plug a 150
amp appliance into a standard 120 VAC outlet. I would need to run whatever
it is from a 5000 watt generator (240 VAC available) if an electric welder
would suit my needs. I think I've seen some arc welder/generator
combinations and I think the engines were smaller than 10 HP so my guess is
that it can be done with 5000 watts.
I don't know how much welding I may wish to do in the future so for now I'd
like the keep the price down as much as possible.
Consider various possibilities, such as using a flange and bolting the
flange to the drum (with appropriate backing and gaskets), or paying a
professional company to do it.
The fist alternative could cost you about $15 and would probably work
just as well as welding, if you can get the backing positioned inside
the drum. Depending on what you do, you can use sheetmetal screws
also, provided that there are no stresses on the joint. etc etc.
You would be unlikely to need 150 amps for this application. Our
expert, no doubt, will correct me if I am mistaken. Just yesterday, I
welded 1/8" plates with 80 amps.
80 amps at 30 volts would amount to 2.4 kW.
You should be able to, but you could also tap into a 240V power, if it
is supplied to your house.
Always a great idea...
A disclaimer, I am as far from being an expert in welding, as it can
"Ulysses" wrote: I want to weld some black pipe, about 3/4 or 1 inch to a
steel 30 gallon drum.
Tell us what you are trying to build. It makes a difference whether you are
building a barbecue or making piping attachments to carry water.
My first thought is that, if you have no welding experience, you may have
trouble due to the difference in thickness between the pipe and the drum
150 amps is output amperage at much lower voltage. I run my 225 amp welder from
a forty amp circuit all the time, no problems ever. It will occasionally pop a
thirty amp breaker but not very often. Volts times amps equals power, and you
can think of a welder as a big transformer which conserves power, so volts times
amps on the input side equal volts times amps on the output side. Input side
voltage on my little welder is 220V and output voltage might be 22V so I get ten
times the output amperage as the input amperage. Very roughly, anyway.
I suggest you look on your local craigslist and find someone local who's trying
to make money welding, and pay him a few bucks to weld it for you. Be aware that
the cheap little 110V MIG welders they're pushing these days run flux-core wire,
and it's real hard to get a nice looking weld with that wire. Lots of guys give
up in disgust. A little stick welder would work but it takes some training to be
able to use one. Same thing for an oxy/acetylene setup, and if you buy one of
those then it's quite a bit to store, and you may have problems with your
homeowner's insurance or even local statutes -- o/a welders cause a lot of fires
and lots of people are afraid of them.
Is your pipe hollow or full ? If it's a water pipe then a good 110 V could
do it without any problem. I've tested a 110V welder at the Miller shop on
3/16 inches plate and the weld were full penetration.
Given that your steel drum would be around 1/16 or less thick and your pipe
less than 1/8 you would be ok.
150 amps times 120 volts is 18000 watts. We must be talking about a
transformer here and measuring the current at that output, right?
What I am trying to build is a wood gas generator. It produces mainly CO
gas by burning wood inside an enclosed drum. The fuel is suspended away
from the bottom and sides. Whatever I use to join the pipe to the drum
needs to be very heat resistant and completely airtight or the generator
I am interested in buying a welder and learning how to weld because I may
make one or two additional units after getting the bugs out of the first
one. I'm planning on using it to run a 5000 watt electric generator which
could be used to run a welder to make more units etc.
| I want to weld some black pipe, about 3/4 or 1 inch to a steel 30 gallon
| drum. What kind of a welder do I need to do this? I have seen some cheap
| arc welders advertised but I have never welded (except a small amount of
| brazing) and I have no idea what it will and will not do.
Unless you're willing to commit to the necessary investment of money and
time to welding, not knowing if it will be the thing for you, you are taking
quite a risk. You'll have to spend a few bucks in change, plus the
accessories that may differ depending on the nature of the job. For this
kind of job, I'd really recommend hiring it out. If you insist, then I
think the least amount of up front expense vs. the learning curve would be
to get yourself a torch set and braze it up. Trying to fit and weld up pipe
of unknown wall thickness to a barrel with relatively thin sheet metal isn't
a task for a newbie on any process. Considering my skill level, I'd be
brazing it, even though I think I could gas weld it. The weld would likely
be weak unless it was reinforced, though. My stick skills would be blowing
holes in the drum all over the place. Brazing with a heavy fillet is plenty
strong and not so hard to do. The part that makes it difficult is the
thickness of the barrel compared to the pipe. The pipe will take longer to
heat up than the thin barrel, so by the time you've got the pipe up to
temperature, the drum has melted through.
I think that you should avoid the little torch and tank sets at the
hardware store. Purchase a torch set, even a Harbor Freight kind will work
for you, and rent a set of bottles that you can return with little out of
pocket if you don't use it enough to justify the expense of rental. If you
like it, spend the money to get some better equipment.
You can also buy fittings made for making pipe connections to drums, if
that might save you a lot of expense and hassle right off the bat.
I need the fittings to be air tight and heat resistant for this particular
project. Are there any fittings with seals that can resist several hundred
Here's what I want to build:
Standard plumbing pipe is probably at least 3 times as thick as the drum so
from what everyone is saying it will be difficult to weld or braze. I'm not
sure exactly how hot it will get during operation but it most likely would
be hot enough to melt solder and burn off epoxy etc.
This isn't a practical weld (having read what you're trying to
You need some skill (minimal training and a lot of practice) more than
you need a "magic box". Whatever you do get, you should also get
yourself an extra box of consumables, a spare weekend and a wheelbarrow
load of scrap metal. Take time out and practice your welding before you
need to use it for real. Most beginner welders (especially car
restorers) screw up because they try to dive straight into the real job
first time. Now does that _sound_ sensible? 8-)
IMHE, you don't need much training. Night classes are really good,
because you get to use big machines without needing to buy them first.
If you're using your own kit though, a book (Gibson's "Practical
Welding" is my recommendation) and that important practice on your own
is enough to do pretty well for starters.
As to welder types, then obviously you should get all three: gas, stick
and wire-feed. 8-) OK, so budget might come into it a bit.
Gas welding is a lovely process and good for neat gas-tight work in thin
sheetmetal. It probably is the best process for doing real gas-tight
welds in this type of work. I wouldn't want to make exhaust pipes
without it. It's also useful (which the electric processes aren't) in
that you can braze with it or use it as a heat source for simple bending
or forging. My gas-welding kit spends more time rigged for oxy-propane
heating than it does for welding.
You _need_ a gas burner as a heat source. Simple propane and natural air
torch is cheap to buy S/H (treat it to a decent hose though) and uses
cheap gas. Very useful to have around. With a few firebricks you're
also on your way to brazing.
Stick welders are great because they're so cheap. If you're needing to
weld angle iron together to make a stand or framework, then it's your
friend. Great for fixing ploughs, hard-facing digging tools and all
sorts of other stuff too. Damn all use on sheetmetal though, which is a
Wire-feed is what I use to stick metal together, day-in day-out. I've
got the others, just never use them. Machine isn't cheap to buy, but
it's cheap to run (unlike UK gas prices). It's also the least
skill-sensitive and the quickest in use. Read that book and do that
Now back to your pipe and drum. This just isn't a good candidate for
welding. It's a hard weld to do, because the metals are of varying
thickness. Also the exhaust from wood pyrolysis is infamously corrosive
and it will attack a joint like this in no time. If you weld it, then
I'd gas weld it with a big thick fillet that was beautifully smooth and
had no voids or penetrations in it. Then it would last fairly well, but
would probably rust through at the edge of the thin pipe going into the
fillet. If I did it with the wire feed, even with my best skill, then
it would still rust through the weld in no time.
So what I'd do here, and for nearly all thin metal joints in woodbunring
kit, is I'd arrange for a large overlapping flange and bolt it together
with a good layer of stove cement between the flanges. It just lasts
I do make woodstoves. I do it with wire-feed welding, I'm careful about
my weld quality and I don't use any steel under 1/8" thick. My "drums"
are made from propane tanks, not 40 gallon drums. I just don't think you
can use such thin steel here without getting corrosion problems.
I guess I'm asking the wrong question. In my ignorance welding and brazing
have the same meaning--I don't really know what either is.
So, I take it brazing is more akin to soldering but at a higher temperature
and with a harder bonding material?
Next question: what do I need to braze some black pipe to a steel drum?
That does seem to be a limitation but it gas gets any more expensive someone
will probably figure out how to do it.
Producer gas was also used extensively in Europe for lighting and cooking
and possibly for comfort heat and hot water. I think some kind of blower
might be needed to make up for the suction from an internal combustion
engine for, say, a water heater etc but since they didn't have much
electricity in the 1800's there must be a way to get it going without a
It sounds like stove cement and flanges would probably work for me and would
save me the trouble of having to learn welding or have it done somewhere.
Where do you get stove cement?
A lot of things here that didn't occur to me such as corrosion etc. I had
thought of using old propane tanks (old because of the change in valves and
they can no longer be filled) but the idea of having to cut the top and
bottom off seemed difficult. But this would probably be easy for you with a