Modern Vespa

Smart move labeling the holes to welded up and those to be left open.

My welder (or I) missed a small hole on the floorboard that needed to be welded up and I have extra holes for the brake light that we missed.

Looking forward to seeing the results!

I like the labeling of everything just as a general practice, regardless of who's doing the work--it's easy to get confused on what's open and what's closed in the moment, and you don't want to have to stop and check.

When I'm doing bodywork, I keep a pencil handy and circle anything than I want to come back to. Makes finding the little things a lot easier and avoids too many "how did I miss that?" moments. Or, maybe even more irritating, the "I know there was a little dent here. Now where is it?"

And BN, you could do your own welding if your garage wasn't full of plants

A last effort at welding.

I could probably get the hang of this with a good 1000 hours of practice.

Definitely a job for a professional.

Sorry if I mentioned this before.

The welding arc seems to act a bit like lightning as it will arc to the highest point it is near. If you try to weld a low spot surrounded by weld boogers it just wants to make the boogers bigger.

Try grinding tacks down before adding more and starting the arc on a tack and dragging it or weaving across the void/joint. If you are left with holes to fill, no worries. Even pros get a few. You will get less as you get the hang of it. Try turning up the amps on your welder.

That is so helpful!

My early tack welds went well. Only problem is that the edges separated.

I could probably do better by tacking, taking of the bead, tacking.

I got small die grinder discs.

As I went along, it got much harder. And harder to see where I should be hitting.

And th worst part was in trying to fill in everything, I made the bead super tall. And the metal was a lot of work to remove!

When amps are too low, the weld doesn't penetrate and material piles up. The charts on the welder are often specify the lowest setting for 22g. Turn it up a notch.

Great tip from Orwell.
By starting on the other tack you are starting on a thick bit.
Once things are flowing - it can be easier.

Add to this: keep your welding head close to the work.
It's a common error for the less experienced.
I have to constantly remind myself.
Gas cools and shields and it really makes a difference if you can get right down on top of the tacking area.
Assume you are MIG welding?

Just thought of another tip. Get a lot of light on the work and brace your arm or the gun on something to keep it steady. Get comfortable. Can't tell you how many times I have laid down a perfect bead just beside the weld joint. This...and the grind as you go reduces excess material that you will have to grind away. At first it feels like it takes longer but it doesn't. You can also true up your work between passes. I think I mentioned the light behind the joint to find pinholes. Mark with sharpie and hit them again.

A few tricks that I've been taught...
- You want to have the sheets touching if possible, to help prevent punching through.
- Back it with a good heat sink, like a copper block or chunk of frozen hamburger
- Practice ahead of time to make sure your welder is set up correctly
- Tack it every inch or so and cool the metal each time before filling between the tacks

Hamburger is a new one for me. Bet it makes the shop smell good.

I blame V oodoo for the hamburger.

How do you like your hamburger done?

3000 degrees on the arc welder.

Crispy on the outside, raw on the inside

This project is now going to become "me learning to weld" for three years.

I forgot my 0.23 wire, so tried with the 0.30 that was in the welder.

I did better this time. Didn't warp the metal. But it just goes on so thick.

I welded with light through the back, so I did get close to covering all the seams, with a couple of rounds of grinding and reapplying.

It's such a challenge! Feels like the tools are not precise.

Maybe TIG welding is easier to control?

As I continue to learn every time I spark an arc, welding is all about using the right equipment and settings, then practice practice practice.

I think your heat setting might still be too low. It looks like the material is still piling up. That and the bits of wire make me think the welds are a little cold.

The heat and wire speed interact, so you have to fiddle with both to dial it in. The angle of the tip and the distance from the weld also change how hot or cold or penetrating a weld is. I have sometimes used a long tip to work distance to deliberately goob on weld material cold to fill pitted areas. It also helps to clean spatter out of the nozzle as it impedes gas flow. Make sure your contact tips are clean. Snip the wire off to the right length when starting a weld.

Just play with it and have fun. It will come. Some days I'm in the zone and some days I just burn shit up even after all these years.

I once brought a sample of my welding to a welder to critique. It was ugly with inconsistent penetration and he was like dude, do you know how much force it would take to break that? Way more than your body could take to survive an accident.

oh yeah! They're definitely holding. Grinding through the surrounding metal is more of a concern.

But I want them to be invisible! Pretty! Like you can never tell there was a weld.

I watched a couple of videos about settings with sheet metal, and there was one that showed the Lincoln Electric welder I am using.

The person set the heat to G (the chart recommends A/B, which is what I used), and tested max with heat/speed, then down from there.

The heat is too low on these ones.

Also, he said the Lincoln Electric starts colder and gets hotter as you do a bead. So just doing little taps, it might be colder.

I just need to practice a bit more.

With these, it's definitely just adding metal. Like soft serve ice cream.

That makes a lot of sense and reminded me. When you weld continuously, the work builds up heat. As it gets hotter, the welds get hotter and you get more burn through than if you were hitting the same area dead cold. As your experience grows, you learn to use these things to your advantage. Sometimes a nice hot weld is just what you need when welding thicker metal and you will want to keep it going to get a nice weld.

Try the stuff you see in videos and see how it works. I have a big tetanus bucket full of bits and pieces of metal I try stuff out on.

Do you have a link to the video?

Btw, getting flat MIG welds on sheet metal is kind of the crux of the biscuit. MIG is notorious among old school, gas welding metal guys as being the turkey pooper of the welding world. They don't care much for TIG either. These are the kind of guys who gas weld without filler rod and planish the joint until it's invisible.

I had to learn on gas and arc (old Lincoln tombstone) before I was allowed to touch the mig machine.

lemme tell ya, mig is a gift sent from the heavens comparatively speaking. especially with sheet metal.

anyway, you need mas inferno hombre. those be cold. it also looks like you're working too far away from the piece. really get the gun in there.

You're right about MIG. Cheap, convenient and gets the job done. I took a night school course and learned stick and gas on the same kind of gear you did. Fond memories of being a college boy trying to fit in among the IROC driving mullets. Sigh...those were the days.

I was touching the brass shield to the metal! I had it slightly spaced out (1/4" – which was recommended in one video).

These ones were helpful! Some were from the "getting started with welding" thread.

Short one "you can do it!"
youtube.com/watch?v=1BYqLM_mY1

This person is a true artist.
youtube.com/watch?v=P8WjdXaw7L4

This one is really helpful, bc he goes through test welds, and welder settings for the one I'm using.
youtube.com/watch?v=qScAlxb34UA

Wire speed too high.
Do you feel the wire bump against the metal?
Turn it town until you don't.

Yes! It was pushing the welder away!

I guess the settings chart on the welder are all wrong.

Thank you.

You probably have the same chart on your welder. I have a 90's Lincoln sp170 with the tap switch. That chart is no use.

Plus side. I found one of these things.

Just going 100% period American bike here.

Has a little surface rust, but the chrome is so good on these, I think will clean up.

Has all the hardware and backrest is perfect.

nice! that'll be a lovely touch on an American market bike!

I seem to have a few of those kicking around as well for some reason! I think they multiply.

Almost every P I've had came with one. They must have been very popular.

They're perfect. Super durable and comfortable for a passenger. And don't require drilling into the frame.

I was watching one of the welding videos and realized I was giving you the wrong info about settings.

My Lincoln is older and uses a tap switch like the Miller the guy has. On tap switches, I think their is a greater range of current that can be drawn through for each setting. Your welder uses a different kind of heat setting switch, so your ABCDE are a totally different thing.

Long story short, you will be turning yours up a lot higher compared to mine, as the welder in the video did. I love the guys Newfie accent.

Question about your bbq rack. Did they usually come with the backrest? I have one with no backrest. Wondering if the po might still have it.

Thanks

Thanks!

This video was super helpful. I can practice settings on a piece of 20 ga, and then dial it down from where it blows holes.

My problem was that it was just building up so much material. But bc my settings were so low. Hoping the next time works! (tomorrow)

I've seen the racks with backrests and without. Seemed like most had them. That was a really common dealer accessory.

If you can find a backrest, it will fit in to yours. They're quite nice.

I love them, bc my early scooter experiences were being passenger. They feel very stable for the passenger.

I had one on my p series 150 clone in the late 80's. It was the only accessory it had. I had a steamer trunk on it when I moved into my dorm room.

Feeling very accomplished.

I was able to do a weld of sheet metal that came out pretty good! So on to the real thing.

I realize that you can fix mistakes with welding. It might take longer, but can turn out ok!

On to the bike.

Looks like you're getting the hang of it. Here's an interesting video : I find with patch panels for anything , they look good and fit close but are not quite right. I would drill the spots and deal with this in two sections. As you probably know, you can buy them individually.
On the SS I am doing, I opted out of these parts and cut out the flats , leaving the spines so I didn't have to deal with compound curves.

Much better!

Those look like much better welds. The warping in your practice piece is normal. The weld material itself is the bigger source of shrinkage. It will always shrink as it cools. The places it doesn't penetrate enough will be revealed by your grinding, then you can just hit them again.

I think you picked the right point in your learning to move from the bench to the bike. As you have seen, it's never perfect, but you can fix mistakes. The final job can look as good as you're willing to put time into dressing the welds. As you get better, you will spend less time filling voids and grinding. This is where you will do a better job than the pros, because you will always care more about your own project and put in the time needed until you are satisfied.

After decades of doing this, I still have to do a few rounds of pinhole filling, especially if I have to weld in a tight or awkward position. I try to make every weld count because I know I will be grinding whatever goes on.

Just mentioning again, keep your heavy grinding on the weld bead itself. It is always lower than the surrounding metal, so blending it so it can't be seen always thins the surrounding metal which you want to avoid in thin sheet metal. Flatten the bead, then hammer and dolly it flush. Or just get it really clean and fill.

Yer doing great. A famous metal guy once said, you can't be afraid of (fucking up) the metal. That's how you learn. We all get the yips the first time we put the torch to our precious bikes, buses or whatever.

That seam...

You could put a piece of copper right beside the seam and weld a little bead. The weld won't stick to the copper so you will get a sharp transition. Don't widen the whole seam...just an inch or so angled slightly so you can blend it where they meet. You could also do it with filler, though filler can pop out when up against a seam.

Aftermarket panels for anything rarely fit right up, so there is always some cheating involved to fool the eye.

I'll paraphrase the Wisdom of SDJohn on this point...

Good info.

Thank you for translating this from 17th century windbag English.