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The method called "Hammer welding"
I recently saw this method on a book i read recently ( Tex smith, How to chop tops)..There was this one car, that fellow named Dave Simard, chopped.He "hammer welded, the seams"..
Could someone tell me more about this method??..since i recently bought gas welding gear If I understud correctly, the weld joint is heated after welding,in small pieces, and hammered flat.. It was nice to see some familiar names, who did the chopping....
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Janne Jarvinen --------- JJ ---------- |
#2
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Janne,
Hammer welding is an old term no longer used. The method of welding is the same as that most often mentioned on this forum. A panel is tack welded at the beginning point, then a second tack is made. as the second tack cools, it pulls the seam edges together possibly causing the unwelded section of the panel to overlap the part it is being weld onto. That second tack is backed up with a dolly and carefully tapped down which stretches the weld and closely adjacent areas to the size before the weld and shrinkage took place. A third tack is then made and it is hammered and dollied back to the point wher the panel edges align. The process is repeated for the length of the panel. Then the panel is welded between the tacks. As the fillin welds are made they also need to be hammered to remove distortion. I was taught hammer welding by a auto builder about thirty years ago. The difference then was that most "hammer welders" would not tack the panel, but completely weld it in short 1/2" sections. After each section the torch was set in a holder and the seam dollied and hammered out while the metal was still hot. Then the spot was cooled with a damp rag and the next section was welded. The goal then was to deal with distortion as the welds were being made. When you were done welding the panel was distortion free. Today, in this time of rubber crutches, shortcuts and a lack of paitience; people weld everything and then pound the crap out of the whole area because,as RodDoc says "they have not learned the basics". Now instead of learning about metallurgy and heat and distortion; we are anxious to get the job to a almost complete appearance, then post it on the internet and ask "what do I do to fix this mess?" This is not true of everyone, so don't get too ruffeled up. However it is a huge problem in how society tries to shortcut tried and proven methods. Hammer welding has not changed. It is still the only way to weld metal together and control distortion.
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Richard K |
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Thanks for the answer Richard..one more basic thing to try.
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Janne Jarvinen --------- JJ ---------- |
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Richard, Do you know if there is a list of terms anywhere on this site? I was a little ruffeled the other day when Roddoc said most of us don't know the basics. Many of us use the basic skills daily but are confused about the terminology. Context is everything: your definition of hammer welding relating to sheetmetal work vs. what hammer welding means to a blacksmith. Then consider regional differences: many times American and British workers, for instance, have two different names for the same thing. I think some sort of list of terms in our context would eliminate both confusion and friction for the group
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Johnny C. |
#5
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Today, in this time of rubber crutches, shortcuts and a lack of paitience; people weld everything and then pound the crap out of the whole area because,as RodDoc says "they have not learned the basics".
Now instead of learning about metallurgy and heat and distortion; we are anxious to get the job to a almost complete appearance, then post it on the internet and ask "what do I do to fix this mess?" This is not true of everyone, so don't get too ruffeled up. However it is a huge problem in how society tries to shortcut tried and proven methods. Hammer welding has not changed. It is still the only way to weld metal together and control distortion.[/QUOTE] i got ruffeled up but in a good way , well said i dont hammer allot but found some other ways to get less distortion however the little distortion i do get after mig welding is cause i dont hammer much
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robert veldman |
#6
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Johnny C,
Good point on terms, names etc. Hammer welding, I would guess got that name in this country to differentiate that process from lap welded joints. Hammer welding denoted a soundly welded butt joint. According to lots of the old body working and collision repair books that I have, many repairs used the lap joint and/or brazing. You see many brazed repairs on 1920s an 30s wire edged fenders. Hammer welding was not a blacksmith term in my recollection. Blacksmiths used a procedure called "forge welding" where the parts where brought to a high heat in the forge, then fluxed and hammered together on the anvil. I may be aware of only regional usage of those terms however. I recently purchased "Performance Welding Handbook" 2nd edition. In the introduction they mention "old Rumors", ideas passed down by older to youger welders which are today incorrect. They mention relieving post welding stress with an oxy/acy torch some preheating methods as no longer valid procedures. It will be interesting to see what is different from the original edition.
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Richard K |
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Hammer welding is as described by Richard where short runs of weld are done and the distortion dressed out. It does not involve cooling with wet rags although some people may do this.
Richard you say that the modern way is to weld the whole thing then pound the hell out of it to get rid of the resulting distortion. The method I use requires that the weld is done in one and the distortion removed after the panel is fully welded, this is neither a modern method nor does it require the hell to be pounded out of the metal after. This method id the one used in coachbuilding since welding was first used. I have seen wings from the twenties welded using the method I use. Very little distortion is caused and so little planishing is needed, no more than with hammer welding. Below is a photo of a weld done in one go (not hammer welding) notice how even the HAZ is and how little distortion has been caused. This weld was done by James my employee. Below is a repair carried out to a model A wing (fender) using the same method. After I welded in the patch I dressed out the weld with a hammer and dolly the whole repair took about four hours and you can see how little of the panel has needed to be planished after the welding was done. David
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Metalshaping DVD. www.metalshapingzone.com Metalshaping with hand tools on youtube http://www.youtube.com/watch?v=IGElSHzm0q8 All things are possible. Last edited by David Gardiner; 06-29-2011 at 06:10 PM. |
#8
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Hammer Welding
What Richard K said was right on the money
I was taught "Hammer Welding" at a VERY good trade school 40 years ago. This method DID weld for 1/2" then GENTLY hammer and dolly the weld while it (the weld) was still red hot, when it looses color and cools, take a damp rag and gently and patiently cool the welded area. The spot welded HAS to be cool , like put your hand on it and feel NO heat. Then move as far away from the first weld and repeat until the whole panel was welded, WITH NO DISTORTION. This could be done on an absolutely flat panel and still cause almost NO distortion. The last time I hammer welded was almost 30 years ago on my '40 Ford pickup, chopped the top 3 3/4". No distortion, you have to know(feel?) how much heat you are putting in the panel. Very time consuming , but with the flatness of the panel, no or very little filler or lead has to be used. (Yes I was taught how to do lead filler work too!. by the way we used ASBESTOS MUD! for real, wonderful heat sink!) David, I notice that there is a stiff compound curve at you welds, might that help hold the shape? If anyone "pounds the hell out of a panel" they do NOT know what they are doing. When I was doing metalwork on older car restorations, I would almost always "choke up" on the hammer handle. Better control, and rarely needed "pounding the hell out of " I use my TIG welder on every thing now, very exacting heat and control Your (old and tired) Pal, Gary
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Gary Anderson |
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David,
My comment " people weld everything and then pound the crap out of the whole area because,as RodDoc says "they have not learned the basics", needs to be taken in its entirety. Your method, which i am very impressed by, to run a continuous weld; maintains control of any distortion in the panel. Your work is outstanding. By simply studying the photos one can gain a terrific amount of insight. I am referring to situations where the entire length is welded in short spurts without paying attention to the welds (many with varying haz's) as the joint is intermittently welded. When this process is completed the person is confronted with a total of confusing different weld sections. Dressing of those weld sections is difficult, so all is overground,overstretched and overworked. Then the shrinking disc is called into action. Then the photos are posted along with the "what do I do now?" In the quarter panel you show you have one long consistent weld. I imagine the dressing of that weld is fairly straightforward (U.S. for fairly simple). This all goes back to basics, as RodDoc says. One needs to be alert and aware of what one is doing. Observation and asking one's self questions aid understanding and enable one to reach a higher level of craftsmanship, learning and self improvement. I am not cheerleading for Tig usage, I am just wondering "why?" Yesterday I was wondering about the audio quality of my DVD sound. Tomorrow is a new day. I'll find something to peak my interest. I learned a lot from this discussion. I hope others did as well. Socrates questioned the status quo in Athens. He was put to death 2400 years ago.
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Richard K Last edited by Richard K; 06-30-2011 at 02:28 AM. |
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Ahhhhh, the hand me downs of mis information
one person can read this entire thread, think "hey. I have it now" and screw it up really bad still. What welding process are we talking about? if a person followed these instructions with MIG weld without grinding down the buildup,, it is probable they would have results that dont meet expectations. Same goes for any buildup of a weld. Also, one mans hammering the hell out of something is another mans " I totaly understand what I am doing, stand back and I will show you the finished prouduct speak for itself". If you choke your hammer near me, I will think you dont know how to control a hammer. I was shown "hammer welding" on a lap jointed, mig welded non ground of the excess panel. Did it help? Dont know. Make it worse? probably. But, this is waht I was shown and would have defended it it at the time with my dying breath, because it is what was shown to me. Now, with todays information age and the free passing of knowlege, we can totally figure out what works and what was snake oil. my post here isnt so much about how you do it, but more on how misinformation can be bad and this forum is the bestest thing to help solve that problem. There are still tons of "myths" out there that are handed down and taught. there is usually a nugget of truth in them. Marty
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