Welding Up?

[glmf]

Most of the advice here is good. Welding uphill on thin metal is not something learned overnight. If the metal is say, 1/4" thick, that will work. 7018, 3/32 wire on about 75 amps DC works very well. I haven't used it on AC, but I think any 7018 can be used on either AC or DC current, could be wrong on that though as its been a while since I hit the books. The technique to welding uphill is to weave the bead from side to side, kind of a whip from side to side. Hold the edges and travel quickly through the middle. As you move sideways, also head uphill slightly. With 3/32 wire, the bead should be about 3/16 to 1/4" wide. And as someone stated, 7018 must be either new, or have come out of a rod oven kept at about 200 degrees. The flux attracts moisture badly and will give you a weld filled with porosity. Even if it looks good, one quick touch with a grinder will show the little specks of trapped moisture.
With you having only a AC welder, I would use 6011 and grind it between each pass. People make a mess when they try to go over some globs, making bigger globs. Grind each pass smooth, and your end result will be much better. I am a pipe welder at a local power plant, and weld high energy steam piping(2200 psi) every day. The people on here are giving you good advice, but the reality is, good stick welding takes some time to learn. If you have a MIG welder, they are much easier to master,,,good luck

 

[patrick_g]

glmf, My hat is off to you and your bretheren, sir. I admire the ability displayed by pressure vessel and high pressure pipe welders.

I recently built version two of a post popper for removing T-posts. It is a ring on a chain and uses the FEL for lift. I used it just this morning when a friend came over to help me set a stretch fixture to terminate a fence. First attempted use popped the chain loose from the bar stock between it and the ring (short piece of pipe.) I just laughed and we reverted to the tried and true but more time consuming wrap the chain around the post technique.

You could tell instantly by casual glance that there was virtually no penetration into the bar stock. It was no stronger than a scant tack. I would have been embarrassed if it wasn't so comical. The moral of the story: It looked really good before it was stressed but it came apart as if it were a crisp dry pretzel.

The two pieces still fit perfectly as nothing was bent and I will just weld them together again with more heat and a lot more attention to what I am doing. I haven't had such a failure since I taught myself to weld using scraps and putting them in a big vise after welding and hitting them with a sledge to try to break the weld. I held "postmortems" over the broken welds and took them as feedback indicating the need for a different technique. Eventually I got to where I just about could never beat a weld apart since the result was then just one piece of metal.

I think my little MIG has spoiled me and when I grabbed the stick to slap this simple little widget together I forgot the basics.

Pat

 

[cp1969]

In a a book about welding, Richard Finch mentions that brazing rod exceeds the tensile strength of a lot of welding rods.

I am looking forward to re-learning welding. I am going to try to take a welding class this fall. I bought an oxy acetylene outfit and am really looking forward to learning how to gas weld. Our shop teacher either skipped it or I was in la-la land that day.

 

[patrick_g]

Charles, Count your blessings, I never had a shop class but sure wish I had every kind of shop class taught.

I managed to learn arc welding (stick, MIG and TIG) through practice, reading, getting advice from welders, and more practice but I only get a good cut with an O-A torch every now and again by accident. I don't gas weld. I barely can cut. My brazing looks like modern art done by a monkey but I can solder really well.

Now that I have a good plasma cutter I can cut steel nicely and after having experienced the advantages of the plasma cutter I am not quite so disappointed that I'm not good with a cutting torch.

Best of luck in your class,

Pat

 

[cp1969]

Well, I might not get to take that class after all. I just got off the phone trying to enroll and found out they haven't had it for the last three years because not enough people enroll. They won't conduct it with less than eight, and so far, I'm the first one to show interest this year.

I will have to look around some more.

Regarding o/a cutting, I remember being taught to use 10 psi acetylene and 40 psi oxygen. Nothing about different tips, different pressures, etc. Now I find out that choosing the correct tip is paramount and each tip will have it's own pressures that it likes.

That sort of explains why 3/8 to 1/2" steel cut so well but everything else was left a mess--probably had the right tip, and 10 and 40 were the right numbers for that tip.

Again, it was probably explained thoroughly, but I was in la-la land. At age 15, I had 'other' things competing for my limited mental capacity.

 

[glmf]

here is some info on O/A cutting. Try 7 psi on the fuel and 40 on the oxy. When you get the flame looking good, hit the cutting stream lever and readjust the flame with the cutting stream on. That long blue/white flame (not really a flame) out of the center hole in the tip is what does all the cutting, the little holes are just preheat. Pure oxygen is all that comes out of the center hole and reacts with the molten metal to cut. The length of that cutting stream is what determines how thick of metal you can cut,,,,surprising as even a small tip will have a cutting stream over and inch long. You can actually get the cut started, and shut off the preheat flame and continue the cut with just the oxygen cutting stream, but it takes a very steady hand, and I have seen it done.
Another tip is to find a piece of angle iron, 2X2 like 1/4" thick or so by say two feet long. You can rest your torch on the vertical leg of the angle iron as a sort of rest and drag it along the angle iron, course this only helps with straight cuts. The cleaner the metal the better the cut, paint and heavy rust should be ground away on BOTH sides of the cut. Slower travel for thicker metal. Tip cleaners are a must, be careful to use the right size as you want a ROUND hole. Tips only last so long, and you can't do a good job with a bad tip. Practice is the key,, good luck

 

[patrick_g]

I have learned more about O-A cutting reading here than I learned from the multi-lingual little pocket sized instruction book that came with the outfit.

Still, given the chance I'll use plasma as first choice, someone else to cut it as second choice and me with O-A as third choice.

Pat

 

[cp1969]

I have learned more about O-A cutting reading here than I learned from the multi-lingual little pocket sized instruction book that came with the outfit.

Still, given the chance I'll use plasma as first choice, someone else to cut it as second choice and me with O-A as third choice.

Pat

Right now, I'm about the reverse of your order:

1. Hacksaw
2. Have someone else cut it
3. O/A (I have the torch but I dont' have any bottles yet)
4. Plasma (Can't use what I don't own)

You can probably go to your torch's website and find good info about tips and pressures. I bought a Smith and their website has a lot of good info, much better than the crummy little multi-lingual book that came with it. I suppose Victor, Harris, and others are about the same.

 

[patrick_g]

Right now, I'm about the reverse of your order:

1. Hacksaw
2. Have someone else cut it
3. O/A (I have the torch but I dont' have any bottles yet)
4. Plasma (Can't use what I don't own)

You can probably go to your torch's website and find good info about tips and pressures. I bought a Smith and their website has a lot of good info, much better than the crummy little multi-lingual book that came with it. I suppose Victor, Harris, and others are about the same.

I have all Victor torches and their little manuals are pretty skimpy. When I ask folks who have had O-A rigs for years about pressures I get the same response, "I DON"T KNOW, I JUST ADJUST BY HOW IT LOOKS AND SOUNDS."

I have (by random selection) accidentally hit on a "GOOD" adjustment for cutting and got fairly good results but alas it was not easily repeated. The plasma torch, to me, is just way simpler to get good results and I don't have to hassle with bottles.

Work out away from the electric grid is about as much hassle as going out with O-A. I have a portable generator that will run the plasma and the required compressor. I would probably be taking a generator anyway to run a grinder, chop saw, or a drill anyway but the compressor is an extra.

Thanks for the tip re checking the mfg web site. It just didn't occur to me.

I hadn't considered the hacksaw since I try to avoid self abuse. 1/2 inch or thicker material of much width, cut in a curve is not my idea of a fun hacksaw task. I'm not that fond of cutting much 1/4 inch with one.

Pat

 

[Jay4200]

The people on here are giving you good advice, but the reality is, good stick welding takes some time to learn. If you have a MIG welder, they are much easier to master,,,good luck

I have a MIGish welder too - a Lincoln 110V wire feed but I use flux-core wire only. In retrospect, I should've used the wire feed - I greatly overestimated the thickness of the bucket metal. Of course, once I had the stick running, I couldn't very well go to the wire-feed (that would be like asking directions while driving...it's just not done).

My stick-welds usually look better than my wire-welds, believe it or not, provided the metal is thick enough that I don't simply vaporize everything (I'm really good at that) and I'm welding flat (of course, hence this thread). I'm sure I could do the multi-position stuff, I just need a lesson.

thanks - JayC