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Denny Kyser
09-02-2010, 05:49 PM
I am a photographer and studio owner and have always built my props and sets using wood, and often wished I could weld, I love to build things and never could with metal.

I purchased a Lincoln Pro Mig 140 to play around with and see if I can do this, always been able to learn anything I put my mind too, so hoping this also is possible.

The only instruction I have had so far is a Covel DVD and youtube, and have learned to look for penetration in the weld to see if its good.

I have a hard time seeing where the puddle is when welding, I am using a auto dim helmet and its set to 9, the lowest power I think. Is there a trick to seeing the seam your welding, or is this something you just get a feel for as you learn.

Also, as far as testing a weld. If I weld something and can not hammer it apart, is is safe to assume it will hold. I realize it will not look great, but talking about strength?

I will post some pics later and ask for some help on how to improve, with my business schedule not sure when I can take a welding class.

Booger Welder
09-02-2010, 05:59 PM
Buy a book and take welding classes at a local Vo Tech or Community College.

You are going to burn your eyes out - with the shade so high.

The purpose of the weld is to melt the base metal with the filler metal. Most times you have to grind back part of the base metal to give the filler metal someplace to go.

You want to hold the gun in one place long enough to create a string and you want to weave the gun back and forth from side to side to get the metal to flow and weave the heat from one part to the other. When you get to the end, you want to stop.

It usually requires a welding table - steel, some C clamps, some vise grips and a lot of patience. A 4 1/2 inch grinder and a air die grinder to get into tight spots. Things like a Dynafile comes down the road when you need to be neater in your work.

Denny Kyser
09-02-2010, 06:47 PM
You are going to burn your eyes out - with the shade so high.


I am a little confused about this, at this intensity, its still very dark, so dark its hard to see the seam your trying to weld, when I go to 10, you can not see anything but the actual arc.

I am using a good welding helmet, not a cheap one.

con_fuse9
09-02-2010, 07:32 PM
The covell videos are informative, the the photography during the weld is pretty much useless. I much prefer something along the lines of HTP's intro to TIG welding. At least there you can see what is going on. I believe they have a MIG video as well. I've never seen the MIG one.

No. 9 shade is O.K. for lower amp flux core wire welding.
I assume you are using flux core wire. Try using a gas shielded wire and up the helmet filter 1 or 2 (like 11). The flux can hide details. With gas shielded (I never use flux) it is easy seeing the wire hit the puddle. You will be able to trace circles around the edge of the puddle with the wire.

See: http://content.lincolnelectric.com/pdfs/knowledge/articles/content/weldinglenses.pdf

As for weld quality. Depending on what you are welding, a couple of poorly placed tack welds might be enough to hold the thing together forever. In most cases, the weld itself should be overkill. But use some common sense. If your welding on a trailer or car that will hit the highway hauling 4000lbs at 70 mph, you probably want to take some care and maybe get someone to inspect your work. If your building a bracket to hold a 20 lbs. flower pot - your probably good. That being said, I would strive for a good looking weld first. If its really good looking, with good wet-out at the toes and you properly prepared the joint, chances are the weld will far exceed the strength required. Beating on everything with a hammer is not quality control. There are some rules of thumb on fillet sizes based on joint sizes and configurations.

Keep in mind your machine is not a very powerful one and that just means you should limit the maximum thickness you weld on. Flux core wire helps to weld on thicker stuff. There should be charts in the owners manual or on the door of the welder to get you in the ball park. You can also pre-heat the base metal and get a little more thickness out of it. If your weld is standing up like a caterpiller, you don't have enough heat.

Denny Kyser
09-02-2010, 08:19 PM
Thanks and I see your point, when I built my studio I converted the 220 line over to a new box and ran the outlets and lights for the studio. I never planned on welding, now I would have to get new service to our home to add 220 so probably not going to happen until I see how good I can weld.
I agree 100% on weld quality, I figure by building some props and fun things while I learn there is little danger of having a bad weld, I strive to make them good but want to justify buying and playing with steel so want to do more than just weld to pieces together.

to be honest, I do not see welding anything thicker than 1/8 inch, and this seems to do a good job at that. I will do much more sheet metal than thicker plate.

I am using the shielding gas, just need to play more and will turn the helmet up a little more. I get great tact welds, its just running a bead that is comical. I would die if a experienced welder saw them, not smooth or pretty by any means.

weldbead
09-02-2010, 09:02 PM
I am a little confused about this, at this intensity, its still very dark, so dark its hard to see the seam your trying to weld, when I go to 10, you can not see anything but the actual arc.

I am using a good welding helmet, not a cheap one.

the lowest shade gives the same protection as a higher one. use one low enough that you can see. use a light on the work if it helps you see. ifyou cant see the puddle well you are wasting your time.

6010
09-02-2010, 09:29 PM
Two things that can cause you not to be able to see what you are welding are ambient light coming in from behind your helmet, and not having enough light directed at the work piece. Try wraping something behind your helmet to keep the light from coming in from behind and try directing some light at your work piece to see if that helps. I have seen many pipe welders attach leather behind their helmet to keep the light out. I guess part of a towel drapped over the back of you helmet will let you know if that is your problem,

I was having trouble welding outside because of the ambient light. I bought a Wendy, a pancake helmet, and that took care of my problem. The pancake helmet does not let any ambient light in at all if you have one that fits properly. It really makes a difference when I am trying to weld outside.

Denny Kyser
09-02-2010, 09:35 PM
Ok, I feel REALLY stupid now, this shows how new I am.
I read the advice on here and realized something was up, I was having to do everything by feel and memory, even at 9. I looked closely and there was a film on the inside of the lens, quite a dark film. When I removed this I was like WOW how cool is this, I can see the wire, turned it up to 11 and could see what I was welding. Things look much better now. :)

tresi
09-02-2010, 11:03 PM
Ok, I feel REALLY stupid now, this shows how new I am.
I read the advice on here and realized something was up, I was having to do everything by feel and memory, even at 9. I looked closely and there was a film on the inside of the lens, quite a dark film. When I removed this I was like WOW how cool is this, I can see the wire, turned it up to 11 and could see what I was welding. Things look much better now. :)

You're not the first. If that's the worst that happens to you'll do all right.