Buying my first welder....confused

Some observations and a question.

O/A will cut non-stainless steel only. You will need something else to cut stainless steel, aluminum, copper, brass, etc.

When cutting angles and tubes (regardless of metal type), I find a chop saw far more convenient and easier to use than O/A. For cutting aluminum, a woodworking table saw with a carbide tipped blade is hard to beat.

O/A can soften metals so they can then be more easily bent with some other means, maybe by hand. For heating metal to the softening point a propane torch can often do the job for me. In many cases metals can be bent without heating if you have an inexpensive bending machine, and by not heating you avoid scale formation and annealing (softening that persists after the metal has cooled to room temperature).

Turning on a propane torch is simply a matter of pressing a trigger, while turning on the O/A torch involves the following steps:

1- Select and install torch tip according to amount of heat desired. 2- Open valves on two gas tanks. 3- Adjust pressure on two gas tanks according to tip size selected. 4- Open the acetylene valve on the torch and light the flame.with a separate flint. 5- Open the oxygen valve on the torch and adjust flame to desired intensity and appearance. Why go through all that hassle with O/A if the propane torch is up to the task? That is the question I ask myself every time I need to heat something.

Good old brazing. Brazing is weaker than welding in many cases. Brazing requires more preparation (cleaning, fluxing, aligning, clamping) than welding in many cases. Brazing temperatures are high enough to anneal most metals. Brazing produces more heat distortion that welding in many cases. You will not be brazing steel to steel if you can weld it. You will not be brazing copper tubing if you can solder it with a propane torch. Brazing is good if you can't weld, or if you need to join dissimilar metals and soldering isn't strong enough and annealing is tolerable.

Now the question. Isn't MIG with fluxcore wire supposed to do well outdoors on dirty rusty metal?

Reply to
Tidrix
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I've heard about using oxy/propane for cutting ... where does one find the appropriate equipment? Does it require a different torch? I assume one can use a standard 20-lb. tank of propane? Are special fittings, regulators, etc. required?

I have thought about going this route, but haven't known enough to begin looking for equipment and prices. Any info anyone can give will be most appreciated!

Reply to
Andy Wakefield

Welding dealer will sell you Oxy-Propane cutting outfit. Propane regulator is the same as used for large Acetylene cylinders with CGA 510 inlet fitting that will fit your 20 pound propane cylinder. Acetylene regulators 's low pressure gage has red danger pressure indicated above 15 psi. Propane LP gage doesn't have 15 psi saftey limit. Ok to use Acetylene gage with propane.

10 cubic foot Acetylene cylinders use CGA 300 regulator inlet fitting. 40 cubic foot Acetylene cylinders use CGA 520 regulator inlet fitting. The Oxcy-Acetylen welding outfits sold at building supply have fittings for small 10 cubic foot Acetylene cylinders and small O2 cylinders so adapters are required for use with large cylinders.

Welding hose is good to maximum 200 PSI from regulator to torch. T grade hose is ok for Propane and Aceytlene LP gas. RM grade is for Acetylene only. Grade is marked on hose.

Different Oxy-fuel cutting torch tips are used for Oxy-Propane than is used for Oxy- Acetylene. A good welding dealer should have them in stock.

I would buy Oxy-fuel cutting outfit from welding dealer. The boxed sets will have Oxy-Acetylene cutting tips. Dealer should exchange them for Oxy-Propane cutting tips. Cutting torch tips are sized for metal thickness..

All new Oxy-fuel cutting outfits should include check valves and flashback arresters.

Oxy-fuel cutting outfits are rated for maximum thickness steel they can cut. Light duty or Medium duty torch can't flow as much gas as heavy duty torch. Regulators with small diameter diaphrams generally have smaller gas regulating orifice than regulators with large diaphrams. This is important when trying to cut 14" steel to make anvil.

Reply to
R. Duncan

Why fool around with junk and wannabes when you can own the real deal? Unless you are sweating copper, or really light stuff that takes only a minute.

Steve

Reply to
SteveB

I only mess around with OA for heating and cutting as I prefer my stick for most all else but for that purpose it isn't all that expensive to buy a set. I opted for the small ( half size) tanks which I bought from a local dealer 4 years back. If I recall correctly they were under $200 or so and I got the regulators and torch set from Sams Club on sale, Victors $135. These I just swap for full tanks as needed which is not all that often, and I use it for cutting which sucks the oxy. The small rig serves me fine and is very handy for trips to the boonies to fix the track on my dozer or something similar. I prefer propane most of the time as its dirt cheap, a barbecue tank fill for $7 lasts all year and the tips don't seem to clog up like the Acy tips do. As for buying the tanks I personally couldn't justify paying $60 / year dunnage on top of the gas when I rarely use that much in gas anyways. As I said in the beginning I don't use this outfit constantly or professionally but it seems to do anything required of it adequately to suit my needs. If you want to save on cutting expenses buy one of those Harbor Freight 14" cutoff saws. Its one of the best things I ever purchased and it gets beat to death and keeps coming back, all for a paltry $60. Compared to those little 4" cutoff wheels that don't last for anything at $1.50 each the big wheels last months for $3.50, go figure.

Reply to
Drizler

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