Modern Vespa

This is a ways down on my to-do list… but would love to hear some opinions on which way to go.

Rust in these pics was caused from battery acid.
It is not structural but there are pin holes in multiple spots and it's wafer thin in places.

Should I treat with phospho and jb-weld?

Should I cut out and patch?

Should I treat with phospho and glass?

Would appreciate your opinions!

I don't have a response, except I'm curious about this also! Following...

One of these, and just cut out the area needed?

These aren't as perfect as they look, though.

Treat it with the rust stuff & bog it... nothing wrong there

On small potholes like that could use a por-15+jb weld combo for something more metal-strength and grindable

I think I'd also go with the POR-15 and/or JBWeld on those.

It looks like it's just the bottom lip. If it were me, I would cut out the pinholed part and make a patch. The contours could be made with hand tools. Mig weld it back in.

For places with just a couple pinholes, I would get the metal really clean, clamp a piece of copper behind the pinholes and weld it up. You can also build up pitted areas with weld material. Zig-zag your welding very fast to build it up, then grind it down.

Option #3 If it's not structural, I'd be here but using this fiberglass stuff:


I used welding and glass fabric from below for the joint at the tunnel


(I love this stuff for any bodywork, tuffer than hell and not as brittle as JBWeld.)


and this fiberglass filler everywhere else. It's my main ride and still looks the same 7 years later.



or maybe this if I was daring and not too scared of wrecking it... Or could you braze with what you already have?

^^^
thought about rust tx and braze... but brazing is so imprecise (at my skill level anyway) it's all gravity and torch gas-pressure moving the material.

Leaning towards rust treatment and jb weld, but as mentioned plenty of time to change my mind 12 times.

Thanks thanks for all the comments and ideas folks!

Sounds like the wisdom of (I think) Sdjohn apply here: "I'm not a great welder, but I'm a great grinder."

If you treat and fill it, just be sure to do the same to the other side.

I'd avoid cutting or filling too much.

1. stop any rot. given it's all dark brown this is likely done, I don't see any fresh rust
2. remove the flakey stuff with phospho, CLR, or evaporust, vinegar... figure out what you have to work with

then reevaluate

You could really do it either way. I agree with treating/painting both sides of the repair. It might last a long time. If you are just touching up, go for it.