Modern Vespa

I'm about to rebuild my p200 frame and have been hesitant to start it because I want to ensure the tunnel rust which I've already neutralized with ospho won't come back and get worse.

While I was at the auto paint store I already asked the sales person about spray attachments to get etch primer inside a tunnel in hard to reach areas. He suggested I try using rust preventer cavity wax instead of primer. They even have a replacement nozzle for the spray can that has a long extension tube to get into hard to reach areas.


The thing about this cavity wax though is that it never fully dries. So you coat the rubber interior with wax that stays wet and keeps water from attacking the metal.

Anyone ever used cavity wax on tunnels before and have any opinions on it? I'm just thinking if I go to town on the tunnel it's going to make a mess of the wiring harness and control cables. Probably doesn't matter except it would get messy when replacing that stuff. I imagine the wax is not going to attack any of the rubber components.

https://www.semproducts.com/product/rust-preventer-cavity-wax/wax

https://www.semproducts.com/product/rust-preventer-aero-wand/71120

An added bonus is the harness and cables will slide right through!

Seams to me - there are always more ways than one to skin a Wasp.
If you go this direction - consider running some pex first?
You can pull your cables and wires through this - and it will also make pulling wires in the future easier.
It's cheap - and you could give it a quick test.
I used it originally - before I went crazy with my whole electrical and made my own harness.
Once run - made pulling wires much easier.

I used master series silver after sandblasting all the rust out. I think something like waxoyl or a similar product would've good if you did the Ospho treatment. I like products like that better than using something like an undercoat. Waxoyl has to be renewed periodically.

There are a couple different options for cavity wax, they're all relatively easy to apply and have varying degrees of mess.

LPS3 - comes in spray cans and will eventually dry to a way film. this is my personal favorite as it's easy to use, easy to clean up.

Boeshield T-9 may be almost the same thing. Its often recommended by bicycle frame builders for coating the inside of the tubes post welding.

Fluidfilm is a lanolin (sheep oil) based product that is well known for preventing surface oxidation (rust). It does not dry but probably carries the most religious conviction about it's benefits (+5 hp) from it's devotees.

KBS Cavity Coater is another. I have no experience with this but the spray can does come with a really long application wand which would really be useful for the tunnel.

All of these generally require reapplication at some point but I'm really talking every 10 years for somewhere like the tunnel that doesn't have regular environmental exposure.

H