What's new
What's new
By:
Advanced search…

Which Material Cannot be welded by gas?

M

monu96

Plastic
Joined
Jul 25, 2019
As a newbie of welding, I just want to know which Material Cannot be welded by gas?
 
monu96 said:
As a newbie of welding, I just want to know which Material Cannot be welded by gas?
Click to expand...
stainless, ti, al, high zinc brass (well, can be...but), si bronze if you are new at it is tricky, corten, copper (see bronze), many more I am sure.
stick with steel, most flavors, to start. Steel is forgiving by nature. no flux, forgives to much/to little o2, flows alright, likes to flow to joint and not away from joint.
 
I've never tried these but this outfit sell fluxes for gas welding Stainless Steel, Cast Iron, Aluminum, and Copper.

Welding Flux - TM Technologies

Edit: Thinking back (waaay back) we did weld cast iron in school as part of welding training. I can't remember if we used flux or not. We used cast filler sticks and used firebricks and a pre-heat prior to welding.
 
The TM Technologies website above has a very helpful tech section on various methods. Aircraft Aluminum welding I believe is still required to be gas.
 
monu96 said:
As a newbie of welding, I just want to know which Material Cannot be welded by gas?
Click to expand...

.
oxyacetylene cannot be used on reactive metals like titanium and magnesium would be a fire hazard even if you had a flux. oxyacetylene requires massive amounts of heat when thickness is over 1/4" and especially when fillet welding a tee joint.
.
tig or tungsten inert gas torch using a arc and usually argon gas is far more efficient. compressed gas is not cheap. if you got enough amps you can tig weld 3/4" thick steel maybe putting down a 1/4" weld and easily weld 2 to 10" per minute. oxyacetylene torch would requires a large flame not only do you have to worry about heat rising shattering electric light bulbs by the ceiling but the cost of acetylene is expensive and it is extremely slow to weld.
.
its 10x easier to make smaller welds with a tig torch and get less warpage. even if material is 3/4" thick there are times where you want small 1/4" welds to get less part warpage.
.
if you put down 100 lbs of weld per year the cost to do by oxyacetylene would be far more expensive than if you bought a tig torch setup and welder and used argon shielding gas. i dont have exact figures but if its
.
over $3000. for oxygen and acetylene and filler metal and takes 100 hours to make 100 lbs of weld or
$2000 for tig setup and machine and argon gas and filler metal and takes 30 hours to make 100lbs of weld
.....just saying it can be cheaper and faster to get better welding equipment especially if you track costs and labor hours required per year
 
I think you're asking the wrong question. Figure it what you're going to be welding and get the right equipment.

The good news is that if you learn OA welding then TIG is easy and fun in comparison.

I've welded Al, stainless steel, and cast iron with OA, so I'd take that first answer with a large grain of salt. A torch can also braze, silver solder, cut, and heat, so it's good to have.
 
In general, not much of anything can be welded by gas ... you'll need a flame.

:)

But if you mean welding with an O/A torch: in addition to wood (mentioned above), plastics are pretty hard to weld without sending it all up in flame.

:):)
 
Tungsten carbide, Magnesium, Titanium, Sodium... Uranium, Plutonium and Radium are also probably bad news generally. :crazy:
 
memphisjed said:
stainless, ti, al, high zinc brass. . .
Click to expand...

In A&P school, 1976, I watched my instructor weld up a 1/2" long crack in an aluminum aircraft intake manifold with OA gear. It was amazing. Nothing happened.... and then with a flick of his wrist a single ripple-less bead went the length of that crack, inside height nearly identical to the outside. That manifold went back into service.

That was the powerplant instructor. The welding instructor at that school had a contract with Boeing to hand-weld tiny stainless beads on solenoid end-caps after coils were in place, part was for the B-52. Beads were less than 1/16" wide.
 
fciron said:
I think you're asking the wrong question. Figure it what you're going to be welding and get the right equipment.

The good news is that if you learn OA welding then TIG is easy and fun in comparison.

I've welded Al, stainless steel, and cast iron with OA, so I'd take that first answer with a large grain of salt. A torch can also braze, silver solder, cut, and heat, so it's good to have.
Click to expand...
how did you get stainless to flow? I have had the seams repel from each other? Forge welding works, then you get iron oxide to act as flux.
 
Are you asking about Oxy-fuel? Do you have any reference books for your course? It’s not like this hasn’t been part of standard instruction on welding for the last 60 + years..
 
As everyone has guessed, odds are good this was a homework question. If not, I'd wager a nickel he's got a garage bet with another non-weldor about "the best" welding outfit.
 
You must log in or register to reply here.

Similar threads

R
Oilfield drill collar question
Replies
14
Views
451
boslab
B
H
Need to source type of steel bolt for welding a finger lever onto
2 3
Replies
45
Views
2K
rogertoolmaker
R
challenger
Tig practic. Do I need to have the gas on?
2
Replies
23
Views
809
Cole2534
Cole2534
T
Getting into a Welding Supportive Role??
Replies
0
Views
296
Taylor’d Metal Co.
T
dgfoster
What is Your Favorite YouTube Training Video Series for Mig Welding New Guy?
Replies
15
Views
617
rons
rons








 

ABOUT PRACTICAL MACHINIST

With more than 10.6 million unique visitors over the last year, Practical Machinist is the most visited site for metalworking professionals. Practical Machinist is the easiest way to learn new techniques, get answers quickly and discuss common challenges with your peers. Register for the world’s largest manufacturing technology forum for free today to stay in the know.

Learn more about us.

STAY CONNECTED

Facebook Instagram YouTube LinkedIn Pinterest Twitter Tiktok

Register Become a forum member. Register today.

Sign Up Sign up for our e-newsletter.

© 2024 Copyright Practicalmachinist.com. All Rights reserved.

Back
Top