Welds???

[DanStokes]

Hmmm.... as I said before, there's a space and place for them all. That said, unless there's a welding process that prevents oxidation, then there's at least one situation where the the epoxy will remain long after the metal has washed away...

To me, it's like this. You can weld stuff together with a $20 Amazon-bought chinese welder, or glue it together with stuff from China. It may work, but, at best, that's 50/50 (being really generous today) chance of failure - worse, with the weld - it may be pretty, but since the machine can't maintain its amps, it's pretty weak. OR, you can properly prepare the surfaces, and bond it together in a manner that will last longer then communism by using a quality welder or quality bonding adhesive.... ymmv. With that said, the lazy factor (aka the 'fudge factor') in either will net results that are not optimal. Often times I see people raging against adhesive but who didn't properly prepare the surface, or worse, didn't follow the temperature limits.... in that case, it ain't the adhesive that's the problem. I swear most think adhesive is like silicone, just fill up the space and call it good.... it is most decidedly not, it takes more prep then a custom paint job - but will reward you with a bond that will never fail.

My experience, too. With either welding or bonding it's usually the operator not the process that's the issue.

Dan

[dave.g.in.gansevoort]

Hmmm.... as I said before, there's a space and place for them all. That said, unless there's a welding process that prevents oxidation, then there's at least one situation where the the epoxy will remain long after the metal has washed away...

To me, it's like this. You can weld stuff together with a $20 Amazon-bought chinese welder, or glue it together with stuff from China. It may work, but, at best, that's 50/50 (being really generous today) chance of failure - worse, with the weld - it may be pretty, but since the machine can't maintain its amps, it's pretty weak. OR, you can properly prepare the surfaces, and bond it together in a manner that will last longer then communism by using a quality welder or quality bonding adhesive.... ymmv. With that said, the lazy factor (aka the 'fudge factor') in either will net results that are not optimal. Often times I see people raging against adhesive but who didn't properly prepare the surface, or worse, didn't follow the temperature limits.... in that case, it ain't the adhesive that's the problem. I swear most think adhesive is like silicone, just fill up the space and call it good.... it is most decidedly not, it takes more prep then a custom paint job - but will reward you with a bond that will never fail.

Referencing the welding side, everyone knows what MIG stands for, right? Maybe it's good...

[milner351]

I took a welding class at the local community college, one of the best things I've done. It was an introduction class - we went through oxy/acetylene, arc, mig, tig, with some lab time on tig aluminum stainless and mild steel. I cannot recommend this highly enough. If that's not a practical solution - invest the money in the "welding tips an tricks" dvds and watch them - Jodi has perfected the filming of welding that really gives you the experience of being inside his helmet.

as for panel bonding - in my experience using modern epoxies in marine repair - I can tell you it's amazing stuff. I have not use metal to metal bonding compounds yet - but I don't see why if the industry uses them regularly they should be avoided?

Just like building engines - when welding, bonding, priming or painting - cleanliness is next to Godliness!!!

[DanStokes]

Panel bonding materials are TOUGH! I have the Flexor system which I chose because the applicator gun was the cheapest at the time. Turns out it's one of the "good" systems. I stuck on quarter panel patches on an old Ford PU that I had and it held well even years later after I passed the truck along to a friend. And those fused area were only clean here and there as I had a heck of a time getting the factory underseal off. So if you can get enough area clean it will still stick though as John said, cleaner is better.

I've also used the Flexor on clean metal and there's no getting it apart once set.

Dan

[dave.g.in.gansevoort]

I took a welding class at the local community college, one of the best things I've done. It was an introduction class - we went through oxy/acetylene, arc, mig, tig, with some lab time on tig aluminum stainless and mild steel. I cannot recommend this highly enough. If that's not a practical solution - invest the money in the "welding tips an tricks" dvds and watch them - Jodi has perfected the filming of welding that really gives you the experience of being inside his helmet.

as for panel bonding - in my experience using modern epoxies in marine repair - I can tell you it's amazing stuff. I have not use metal to metal bonding compounds yet - but I don't see why if the industry uses them regularly they should be avoided?

Just like building engines - when welding, bonding, priming or painting - cleanliness is next to Godliness!!!

Absolutely correct. I took a welding course back in the 70's and I had been welding at that time for about 10 years. Dan and I stuck a few cars together in the 90s, one in particular was a front clip job. Dan did the pretty work, I did the structural stuff. And then there was the Mini. Should have waited for Dan on the pretty work...

Oh well I'm on to better things now.

[SuperBuickGuy]

I took a welding class at the local community college, one of the best things I've done. It was an introduction class - we went through oxy/acetylene, arc, mig, tig, with some lab time on tig aluminum stainless and mild steel. I cannot recommend this highly enough. If that's not a practical solution - invest the money in the "welding tips an tricks" dvds and watch them - Jodi has perfected the filming of welding that really gives you the experience of being inside his helmet.

as for panel bonding - in my experience using modern epoxies in marine repair - I can tell you it's amazing stuff. I have not use metal to metal bonding compounds yet - but I don't see why if the industry uses them regularly they should be avoided?

Just like building engines - when welding, bonding, priming or painting - cleanliness is next to Godliness!!!

your last sentence hit on the issue. Factories can control most of the variables to get a good bond. With that said 3m 8115 and 8116 are very, very good for the home builder BUT follow the instructions or waste some pretty expensive epoxy. Waste is the other issue, unless you're using the entire tube - you risk spending a lot of money for epoxy for very little use. Granted, the 3m stuff I talk about - you can replace the nozzles (thus preserving the epoxy for a year or two) but even those are $3.00 each so the expense vs. a tack from a MIG just doesn't pencil out. With that said, it's the only way I know to fuse dissimilar materials in a permanent fashion (e.g. aluminum to fiberglass)

[dave.g.in.gansevoort]

your last sentence hit on the issue. Factories can control most of the variables to get a good bond. With that said 3m 8115 and 8116 are very, very good for the home builder BUT follow the instructions or waste some pretty expensive epoxy. Waste is the other issue, unless you're using the entire tube - you risk spending a lot of money for epoxy for very little use. Granted, the 3m stuff I talk about - you can replace the nozzles (thus preserving the epoxy for a year or two) but even those are $3.00 each so the expense vs. a tack from a MIG just doesn't pencil out. With that said, it's the only way I know to fuse dissimilar materials in a permanent fashion (e.g. aluminum to fiberglass)

Wait, what? I can't weld tinfoil to tissue paper? Just kidding...

Good discussion about welding. Let's veer off to brazing, or silicone bronze welding as some call it. I've used oxy-acetylene torches to braze things, including bicycle frames, but never used tig. Tips, tricks, advise, horror stories, and/or videos let's see where this takes us. Thanks

[SuperBuickGuy]

Wait, what? I can't weld tinfoil to tissue paper? Just kidding...

Good discussion about welding. Let's veer off to brazing, or silicone bronze welding as some call it. I've used oxy-acetylene torches to braze things, including bicycle frames, but never used tig. Tips, tricks, advise, horror stories, and/or videos let's see where this takes us. Thanks

if you can torch, you can tig. The only real difference is how fast the puddle heats... add a modern, inverter (NOT Harbor Fright) welder - and you'll be a pro in no time. Inverters vary the heat for you, thus you get good penetration and a nice, controlled puddle.

[anotheridiot]

if you can torch, you can tig. The only real difference is how fast the puddle heats... add a modern, inverter (NOT Harbor Fright) welder - and you'll be a pro in no time. Inverters vary the heat for you, thus you get good penetration and a nice, controlled puddle.

I really loved the AHP box with the thumb switch. I could tig with that. Their pedal is just on or off, not increase heat or reduce it. Got the lincoln 275 and I cant get the pedal right at all, but my son can weld beautiful beads so I settle on the fact its his job and break out the mig when I have to weld something.

[dave.g.in.gansevoort]

I have a 20 odd year old Lincoln Square Wave 175. It's not a modern inverter machine, but it's really stable for steel and aluminum. When I get to tig brazing it's what I'll be using. With the pedal it's really controllable. Hopefully it'll work...

In the past when I made headers, I'd tack the tubes to the flanges while bolted on a dummy block in the car. As I had gas or stick only in those early days, I'd use a small diameter 6013 rod and weld the engine side of the tubes to the flanges. Then braze the outside on the bench. This seemed to work really good but then again dirt car headers didn't survive very long anyway. Rocks, clods of clay, other cars, pretty much beat them up before fatigue was a factor.

Now I would like the Whatever project headers to survive so I'll tig the flange side, and braze the outside. Time will tell if I have the chops to tig braze...

[SuperBuickGuy]

the 175 will work perfect for what you're doing. It's funny, yesterday I was talking to another friend about welding - it's been 35 years since I regularly used a torch, now it's just for heating up bolts, cutting and brazing... and I usually get grief from my gas supplier that the tanks need to be hydrotested since they sit for so long.

using silicone bronze with a tig is fairly easy - it does gas a bit and adhere in a ball on your tungsten, which means you'll be grinding it off regularly. personally, I'd use a steel rod instead because it's quite a bit stronger.

also with tig, if you wear glasses, you'll want to use your reading glasses to weld.... bifocals are almost useless.

[SuperBuickGuy]

I really loved the AHP box with the thumb switch. I could tig with that. Their pedal is just on or off, not increase heat or reduce it. Got the lincoln 275 and I cant get the pedal right at all, but my son can weld beautiful beads so I settle on the fact its his job and break out the mig when I have to weld something.

I've tig'd since I was a kid - my dad owns a sheet metal shop that does restaurant equipment - a long, long time ago I learned that you don't have to lay dimes to have a great weld. Matter of fact, I had one boss that would inspect pretty welds far more then other welds because he (rightly, I think) believed that if you were concentrating on pretty, the weld won't be strong. Of course, the exception is aluminum - it can be pretty and strong.... for that I have a grinder. With that said, if you weld aluminum regularly, pretty welds aren't terribly hard (and we're back to torch welding, where timing makes for pretty welds - dip, 2, 3, dip, 2, 3, dip, 2,3)...

[dave.g.in.gansevoort]

the 175 will work perfect for what you're doing. It's funny, yesterday I was talking to another friend about welding - it's been 35 years since I regularly used a torch, now it's just for heating up bolts, cutting and brazing... and I usually get grief from my gas supplier that the tanks need to be hydrotested since they sit for so long.

using silicone bronze with a tig is fairly easy - it does gas a bit and adhere in a ball on your tungsten, which means you'll be grinding it off regularly. personally, I'd use a steel rod instead because it's quite a bit stronger.

also with tig, if you wear glasses, you'll want to use your reading glasses to weld.... bifocals are almost useless.

I still take my glasses off when I weld. It's funny I've had progressive bifocals for years. And I like them for reading, computer screens, and the like, when I'm looking up and back, changing focus . But for detail work I don't need them. I keep a cheap pair of wrap around safety glasses to protect my eyes in the shop. Up close work is just clearer that way. The doctor doesn't understand why but his test confirms that as well. I'm just an enigma wrapped up in an anomaly, inside of a dichotomy! At 67 I'm not complaining.

[SuperBuickGuy]

I still take my glasses off when I weld. It's funny I've had progressive bifocals for years. And I like them for reading, computer screens, and the like, when I'm looking up and back, changing focus . But for detail work I don't need them. I keep a cheap pair of wrap around safety glasses to protect my eyes in the shop. Up close work is just clearer that way. The doctor doesn't understand why but his test confirms that as well. I'm just an enigma wrapped up in an anomaly, inside of a dichotomy! At 67 I'm not complaining.

I'm pretty sure that's what Dan says about you too.

problem with bifocals is the welding hood lens is above the magnification line.... I wear reading glasses but use a lens that mounts in the helmet, otherwise, I'm welding blind

[MP&C]

With panel bond, this is something the factories use on a daily basis. But one area it is not used is down through the middle of a quarter panel, as gets done in many repair jobs.. This typically results in a ghost line visible in the paint showing EXACTLY where the seam is located. Basically two thicknesses of metal will expand and contract at a slower rate that the single layer right next to it.. Given enough heating and cooling cycles (think car shows) the seam between these two panels will indeed show.. If you can put the seam where it is not visible, then it may be a better option... Down through the middle of a panel, better chance than not that it will show up in a ghost line..


Here's the reflection in a lower tailgate repair that shows this exact issue. A flanged seam was used, just like one for panel adhesive requires.

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