Tig welding panel

More of an art than a science - discuss metalworking and welding here.



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PostPosted: Sat Sep 21, 2013 1:32 am
norunz wrote:one trick to do is to use your blow gun, crank the air pressure way up, stich your weld, then immeaditly blast it with air, it will cool the area quickly, if your not good with a tig set up, your better off using mig, a quick stich and let it cool, if your not good at tig you will be on the metal with the heat to long and it will warp

is it a good idea to cool your weld immediately?? my thoughts would be it would make the weld area very brittle and then would require annealing?? its only wat i have read and been told, but then others say to quench the weld with cold air/wetrag, i thought it would also shrink the welded area more as the process of heat shrinking is the heat the metal and cool it very quickly, altho when shrinking there is no need to get it as hot as welding??
can some 1 else pls verify this as i also use a tig to weld in my panels and am confused with conflicting theories and procedures.
cheers, krem



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PostPosted: Sat Sep 21, 2013 3:14 am
When using the shrinking disc, most of the guys recommend that you only get the metal hot enough to make steam when you mist it with water. They also say that you can allow the metal to cool naturally, but it won't shrink as much.

That same logic holds true for welding or any other way of heating the metal. If you could heat the metal very slowly and let cool just as slowly, there wouldn't be any shrinking, so its always best to let it cool naturally if shrinking is not desired, without any compressed air or water.IMO

edit: The idea of the disc is usually to just shrink the high spots, so if you get the whole area hot and mist with water, then the whole area will shrink. So just heat the high spots enough to make them steam.



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PostPosted: Sat Sep 21, 2013 9:00 am
XR7 wrote: I hope you all don't mind a good old fashioned thread hijacking, :goodjob:


not at all

Check this out
http://www.youtube.com/watch?v=Rv5bKXJ3kEM
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PostPosted: Wed Jan 15, 2014 8:57 pm
chevman wrote:When using the shrinking disc, most of the guys recommend that you only get the metal hot enough to make steam when you mist it with water. They also say that you can allow the metal to cool naturally, but it won't shrink as much.

True. The panel only has to be hot enough to cause seam with you wipe it with a wet rag. I use a wet rag some use a spray bottom of water.
chevman wrote:That same logic holds true for welding or any other way of heating the metal. If you could heat the metal very slowly and let cool just as slowly, there wouldn't be any shrinking, so its always best to let it cool naturally if shrinking is not desired, without any compressed air or water.IMO
True about letting the metal cool naturally, but not really true about no shrinkage when welding. Welding sheetmetal always causes shrinkage the goal is to minimize the shrinkage, so that it can be easily corrected with a hammer and dolly or very little filler will be needed. To correct any shrinkage using your hammer and dolly only hammer on the HAZ area of the panel. That is the Heat Affected Zone that area that turned color while welding. Its what is causes the shrinkage. If you stretch the metal in that area the shrinkage will disappear. Keeping the shrinkage to a minimum is harder on a flat panel than on a panel with some crown.

By way tig welding panels is wonderful but a mig will do fine. Where tig shines is in the metal finishing. Its less grinding and you have control over the heat which gives you more control over the shrinkage and its a less brittle weld bead than mig. You can hammer and dolly to your hearts desire without worry or cracking a weld.



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PostPosted: Thu Jan 16, 2014 9:01 am
BAM55 wrote:True about letting the metal cool naturally, but not really true about no shrinkage when welding.

I don't think I said there wouldn't be any shrinkage when welding, just less shrinkage when cooled naturally.
We are in complete agreement with every thing else you said in this post. :allgood:

BTW, I picked up on a suggestion from a ace tig welder to up the power considerably and fuson weld (without filler rod) at a quick pace and get a lot less shrinkage. Of course all the saved welding time must be spent on fitting the panels for a perfect seam, in order to weld without filler rod. I have been trying it and it does work very good.

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PostPosted: Thu Jan 16, 2014 12:29 pm
chevman wrote:
BAM55 wrote:True about letting the metal cool naturally, but not really true about no shrinkage when welding.

I don't think I said there wouldn't be any shrinkage when welding, just less shrinkage when cooled naturally.
We are in complete agreement with every thing else you said in this post. :allgood:

Sorry I think without looking at each other when we speak things get lost and confused. I was actually agreeing with you and only intending to expand on what you posted. I only wanted others to understand that anytime heat goes into a panel there will be some shrinkage sometimes very little or noticeable but its still shrinkage. I only said that because when I started I thought something was wrong with me.lol I took my time welding and still had very minimal distortion. Then I learn all about the HAZ. So we are in 100% complete agreement on everything.lol
chevman wrote:BTW, I picked up on a suggestion from a ace tig welder to up the power considerably and fuson weld (without filler rod) at a quick pace and get a lot less shrinkage. Of course all the saved welding time must be spent on fitting the panels for a perfect seam, in order to weld without filler rod. I have been trying it and it does work very good.

Yes I do fuson welds also. Its a beautiful thing isn't it. Tig welding sheetmetal is a blast. :happy:



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PostPosted: Fri Jan 17, 2014 9:03 am
What are your guys setting for welding sheet metal?

What size tungsten are using cup size etc I'm still not welding worth a snot with mine of course I haven't been able to spend much time with it at all either.

I was trying to weld some Spring material yesterday Trying to make some new Hammers I cant do nothin right
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PostPosted: Fri Jan 17, 2014 12:34 pm
Doright wrote:What are your guys setting for welding sheet metal?

What size tungsten are using cup size etc I'm still not welding worth a snot with mine of course I haven't been able to spend much time with it at all either.

I was trying to weld some Spring material yesterday Trying to make some new Hammers I cant do nothin right


It depends on metal thickness. Most sheetmetal I deal with is around 18 gauge. For that I use use a 1/16" 2% Ceriated tungsten (You could use a 1/16 2% Thoriated also) sharpened to a sharp point, my cup size is a 5 or 7 depending on if I need to get into a tighter area, and 1/16 ER70S6 filler rod. My amperage is set to around 48. Try 1 amp per .001" of metal guide line and see if it works for you, it does for me. 18 gauge is .0478 metal thickness. I have also used 3/32 2% Ceriated tunsten with 1/16 filler rod on 18 gauge sheetmetal with great success also but I prefer 1/16. When it comes to welding everyone's technique is different and you just have to find your niche and what works for you. There are guidelines but you have to find your own groove. There are guys who will bump up the amps and fly across a panel, there are guys who are slow and deliberate, and some are somewhere in between.

With this panel I welded around 10 inches at a time, stop hammered on dolly on the HAZ before I continue. When I was done there was very little distortion left in the panel, which a little more hammer and dolly work could easily correct.
Image

Image
Last edited by BAM55 on Sat Jan 18, 2014 12:50 am, edited 1 time in total.



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PostPosted: Fri Jan 17, 2014 4:29 pm
krem wrote:
norunz wrote:one trick to do is to use your blow gun, crank the air pressure way up, stich your weld, then immeaditly blast it with air, it will cool the area quickly, if your not good with a tig set up, your better off using mig, a quick stich and let it cool, if your not good at tig you will be on the metal with the heat to long and it will warp

is it a good idea to cool your weld immediately?? my thoughts would be it would make the weld area very brittle and then would require annealing?? its only wat i have read and been told, but then others say to quench the weld with cold air/wetrag, i thought it would also shrink the welded area more as the process of heat shrinking is the heat the metal and cool it very quickly, altho when shrinking there is no need to get it as hot as welding??
can some 1 else pls verify this as i also use a tig to weld in my panels and am confused with conflicting theories and procedures.
cheers, krem

that's what`s great about low carbon mild steel, you can get it cherry red , even white hot, and quench it and it will not become brittle



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PostPosted: Sat Feb 08, 2014 3:19 pm
Bam I like your 1 amp per .001
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