Just picked up a nice oxy/act outfit for welding and I can't wait to give it a go. I hear its possible to make nice welds and would love to see your work. Any tips before I start would be awesome too. Is this also called Hammer Welding?
Hammer welding is done when you have welded and then using a hammer & dolly the bead is hammered flat while still hot, It takes some practice to be done right. usually done with gas welding but can also be done when tig welding if you quick enough.
I did this yesterday. It's a "cat walk or two lip" panel that was hacked together on a 57 bird. The panel had been mig welded in with the inner structure of the car pushed over 1& 1/12" I needed to add to both ends of the panel. I had to separate the skin for access
I O/A welded a 1&1/2" strip of 18 ga. on the end of the skin. I did it with little correction during the weld. Tacked every 3" hammered the tacks. Then welded, pretty much just let it move how it wanted. Hammered only to maintain alignment of the seam. Then filed the weld bead then planished on my RR track, followed by a few passes on the air planishing hammer. Total time about 2&1/2 hours. Not a metal finish, but close. This piece will lap over the quarter and be leaded same as the factory. This is why I like my torch
No it's not. Hammer welding is when you heat both pieces and then hammer them until they fuse. I won't go into the whole process. What you are thinking of is simply hammering your welds AFTER they are already welded to flatten them and decrease any warpage.
Hey Tin, Yer gas welds look sexy But tell the truth, don't ya miss all that grinding, and changing disc to grind down those hard- as- hell squirtgun welds? The rebuild of that bird is lookin more like an archaeclogical dig than a resto, but hey, it keeps ya off the streets, no?
OK can somebody do a quick gas welding 101 please? Like what tip to use on the torch and what rod to use etc. etc. etcccccc. Thanks....
Sexy welds! why thank you Ha! You bet I hate grinding. I think it comes from too many years of heavy collision. Many, many hours spent grinding Mig plug welds. It's funny, so many guys get bent out of shape when I tell them to put down the mig and gas weld. I'm not trying to put anyone down, just trying to make life easier for them! I'm actually enjoying the bird. But I might be kind of a masochist! It's pushing my limits and making me learn. I think that's what has kept me in this work. Plus I took the car on my terms. I do it exactly like I want, it takes what it takes, and I only do the metal, and the lead....if I feel like it I don't think there was a long line of guys wanting to take this on!
I use a standard torch with a 00 tip. There can be some variance in tips so you might like one size bigger or smaller. I use 1/16" mild steel rod. I prefer a slight gap and use the rod as necessary. When I try not to add filler rod I get too much undercut. I use about 4 lbs on both gas and oxy. I think that reduces flame pressure, and helps to hold a puddle without melting away the base metal. If your flame is popping or unstable, you may have to increase the pressure. Then start a puddle and dip the rod into the puddle. I like to hold both the torch and rod @ 45 degrees. Hold the rod right at the edge of the puddle till you need it. That's the hard part. Don't melt the rod onto the base metal then melt it in. That's the most common mistake. You have to "walk the line " between melting the base away and keeping the puddle liquid. You dip the rod just enough to keep the puddle from melting away the base metal. Feeding the rod and torch angle and distance manage heat along with flame size and adjustment. To set up your flame light the gas first. Turn it up until the black smoke clears up, but the flame is still on the tip w/o a gap. Then add oxy until the yellow orange "feather" recedes back to the blue flame, or cone. It should be rounded not sharp. You can adjust up or down with the same tip to a point. Just keep the gas and oxy balanced so you have that neutral flame with the rounded blue cone. Now practice! A lot! Not on your car until you get it down!
Good advice Tinbender!!! My High School shop teacher told us to always use a "Quiet Flame" If you need to turn the flame up so far that it makes the "whoosh" sound you need a bigger tip He also made us run damn near perfect beads on 16 ga. without filler rod before he would let us weld 2 pieces together using filler rod. Many thought him to be a hard ass prick, but what he did was pound the fundamentals for proper puddle control and filler rod technique into your thick skull before you were allowed to move to the next level. After the ass kicking we got learning gas welding, learning to stick, MIG and even TIG was easy.
You guys make gas welds look like they are machine welds... Hows the penetration and strength as compared to electric welds? Would you trust a tube chassis/roll-cage that was gas welded instead of mig/tig welded? More pics!
You guys make gas welds look like they are machine welds... Hows the penetration and strength as compared to electric welds? Would you trust a tube chassis/roll-cage that was gas welded instead of mig/tig welded? More pics!
From the beginning of aviation up until the 80's the only FAA approved tube airframe and engine mount welding was gas. Some of this had to do with preheating the 4130 chrome moly tubes to remove stress. It was sure strong enough to hold a 1000+ Hp radial engine on the wing of a ww2 bomber. John
Prior to the invention of heliarc welding in the 40s, gas and boiler pipe was gas welded as well as aircraft parts. Today, I don't think gas welded cages are legal for use by NHRA or other racing origanizations, not because a gas weld is a poor choice, but because of the skill required to produce a sound one for use on a cage or chassis. When made properly, the penetration on a gas weld is fantastic, much as on a fusion weld, because filler rod is only added above the root of the weld. Strength of a gas weld is dependent on parent metal, and filler rod quality and the good netural flame used that doesn't leave the finished weld or surrounding metal brittle from oxidization or weak from a cold weld caused by a carburizing flame.
Prior to the invention of heliarc welding in the 40s, gas and boiler pipe was gas welded as well as aircraft parts. Today, I don't think gas welded cages are legal for use by NHRA or other racing origanizations, not because a gas weld is a poor choice, but because of the skill required to produce a sound one for use on a cage or chassis. When made properly, the penetration on a gas weld is fantastic, much as on a fusion weld, because filler rod is only added above the root of the weld. Strength of a gas weld is dependent on parent metal, and filler rod quality and the good netural flame used that doesn't leave the finished weld or surrounding metal brittle from oxidization or weak from a cold weld caused by a carburizing flame.
Hell I've hesitated to post closeups of my beads cause they look like shit compared to the TIG I see guys do Like stated gas has been used for years for all kinds of welding. I like it because of the malleability. But I only use it for butt welding sheet. I use my mig for structural and anything I plug weld. I also have a resistance spot welder that I use the hell out of. But it's only for spot welds. I'd like to get a TIG, but I'm nearing retirement in the shop and have other things to spend money on.
The fattest section of a tuned twostroke exhaust I started making as a practice project shortly after getting my Henrob O/A welder. I had no welding experience, just seen some demo videos on youtube and read a handbook. What you see in the pic is probably a third of all welding I had ever done at the time, so there's a good reason it's not perfect. Under those circumstances I'm pretty happy with it, but I want to keep getting better ofcourse. 0.7mm (0.028") mild steel, fuse welds mostly, filler added only where the gap was too large to make fuse welds. All sheet metal shaping done with a simple mallet over a steel pipe, so no fancy tools used.
Very nice G-son for so little practice. This thread is awesome. I've learned a lot in its short life so far! I've always heard that if you can gas weld you can weld using any other technique.
Nice job G-son! My first "real" gas welding project was a pipe just like that one! This again proves my point. It's not that hard. If everyone that gets a torch or a MIG would take a few hours and learn BEFORE they try to weld on a car, they would be surprised just how easy and basic this skill is to learn.
Here's a quarter panel in progress, and after oxy/acety gas welding. Put about 300,000 miles on this (Shorty).
Ya know what's funny? Hammer welding is a hell of a lot harder on a flat sheet of metal than on something curved! I have done quite a bit on panels for stuff over the years, but I'm no expert, and today actually decided to sit down and experiment some more and actually deseminate the process so I could teach a freind how. On a flat sheet I had a hard time determining how much I had to hammer the welds to keep everything from shrinking. Weird...
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