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zobman
09-08-2008, 09:15 PM
I have been tring to weld up a seat frame out of 1/2" E.M.T. I am using a a Clarke 130EN Mig welder, with .023 wire and Argon gas. I have ground the galvanized down and fishmouthed the tubing, but everytime I try to weld it up, it just spits and sputters and I can not get the weld to flow. I am using 1 and 2 for heat and wire speed at 3 and 4. Can any body give me any help? PLEASE!!!!!!!!:confused:

ggriffin924
09-08-2008, 09:37 PM
I have a millermatic welder and the settings I've been using 6 voltage, and 30 for the wirefeed. I've found if I pull back a bit farther then normal, the emt does weld up. I don't even bother removing the coating for the conduit, I still blow through but not bad. I also have my gas at 30 fpm on the flow meter. I'm still pretty new to the hacking scene, but for some reason, my welding on emt, looks better than on the square tubing. Oh, I have been told to watch the fumes from the emt coating,,, so be carefull about that, if you don't remove it.


I have been tring to weld up a seat frame out of 1/2" E.M.T. I am using a a Clarke 130EN Mig welder, with .023 wire and Argon gas. I have ground the galvanized down and fishmouthed the tubing, but everytime I try to weld it up, it just spits and sputters and I can not get the weld to flow. I am using 1 and 2 for heat and wire speed at 3 and 4. Can any body give me any help? PLEASE!!!!!!!!:confused:

John Lewis
09-08-2008, 10:16 PM
but everytime I try to weld it up, it just spits and sputters and I can not get the weld to flow. .... Can any body give me any help? PLEASE!!!!!!!!:confused:

There is galvanizing on the inside of the tube too. That may be what is causing problems. I braze and have to clean it right off. I use hydrochloric acid (Spirits of Salt) in water. Remember add acid to water not vv. I soak the ends of the tube to etch off the plating then wash thouroughly and neutralize with bicarb soda solution. Take appropriate safety precautions!

I have been told that a bit higher current is needed when arc welding galvanized material. Trouble is that can burn holes in thin material.

The zinc fumes can be a problem. The old remedy if you poison yourself was to drink plenty of milk. I think from memory the poisoning manifests as stomach cramps etc.

John Lewis

jimFPU
09-09-2008, 08:55 AM
Right John:

http://www.wisegeek.com/what-are-the-symptoms-of-zinc-poisoning.htm

macka
09-09-2008, 10:33 AM
I use muriatic acid to remove the coating, you can get it cheap at hardware stores in the pool cleaning supplies area. Use it pure in a mason jar and dip the end in you want cleaned for welding. Then wash it with cold water. I also do this with sheets of galvanized in a plastic bucket. ALWAYS wear eye protection and I put a fan between me and the bucket to blow the fumes away from me. Do this in an open area, as the fumes can cause the other metals around to start corroding.

trikeman
09-09-2008, 01:06 PM
I can't really speak to welding EMT seats with solid wire, because when I did my DW mesh seat frame out of 1/2" EMT I used flux core, I didn't have much trouble. All I did was to sand the zinc off the outside with my flap wheel. It is more difficult to weld small tube because it is always moving away from the wire. It has been quite a while since I did it, but as I recall I used the door settings for 16 ga metal on mine and it worked fine.

One thing that may be giving you trouble is that the 1/2" tube has so much curvature that the gas may be having trouble shielding the weld. I know when I have inadequate gas flow my Hobart 140 will spit and sputter with solid wire. You might therefore try turning up the gas.

savarin
09-09-2008, 07:30 PM
One thing that may be giving you trouble is that the 1/2" tube has so much curvature that the gas may be having trouble shielding the weld. I know when I have inadequate gas flow my Hobart 140 will spit and sputter with solid wire. You might therefore try turning up the gas.
and if welding outside it may be a light breeze is also blowing the gas shield away.
Does the wire actually poke the work hard enough so you can feel it jab?
if so turn up both the gas and the power.

gbbwolf
09-11-2008, 09:24 PM
I used flux core .030 wire when I did mine same welder though clarke 130en.
Wire speed was 5 1/2 and setting was 1 for power.

At 1 on power you will not blow through and 5 on wirespeed will keep the puddle flowing nicely.

Worked for me on the 3/4 emt.

Do short welds do not try and do a complete weld all the way around at once it will get too hot and burn through.

Like I said worked for me when I made my extended handlebar stem.

Nelson

macka
09-11-2008, 09:52 PM
just a few extra tips to make life easier.

1. get comfy, you always weld better when you aren't supporting your whole body, your arms are braced amd your work is locked down

2. fitting. Always fit your tubing as tight as possible. If you can get your tubes snugger then the width of your wire, you will get a better weld. I like to give my tubing a small chamfer where possible to get a better seat on the bead.

3. test weld. Yep thats right, take a small piece of scrap if you have it and give it a test weld. You can see if you are set up right for good penetration and if you have a good set up, then log the settings (you never know if someone will change them)

4. I always tack at the 12,3,6,9 o'clocks to start on tubing so I lessen the warpage, then I clean the welds, then I weld from 12 to 1:30, 3 to 4:30 6 to 7:30 and 9 to 10:30 then I fill in the gaps after I clean the starts and stops.

5. If I am joining 2 tubes with a tube gusset I drill a small relief hole so I don't get blowout from the hot gasses in the small tube.