I'm either warped or stupid. Tell me which.

So, as is no suprise to anyone on this forum, my project challenge car has snowballed into the deep end.

Currently I am stripping it to a bare she'll.

Planning on seam welding the entire chassis, cleaning and painting every surface, and with the addition of Steve Stafford to the team, full cage.

We've been working at removing undercoat and seam sealer with the harbor freight oscillator tool and various scrapers. But all the stuff that seems to want to come off is off. The rest is in nooks and crannies, or hard as concrete. Hell, it may even be concrete.

We have one of the pressure washer sand blasters that Toyman used on the bus for doing all the paint and rust removal. But the rest of the seam sealer and undercoat is kicking our ass.

So, two topics:

1. How the berkeley do we get the rest off?

2. Full seam welding, or stitches of on/off 1 inch, and why?

Removing undercoat/seam sealer? Dry ice, most groceries will sell it

Are the only choices warped or stupid?

You acid dip the whole chassis then quickly rinse and paint.

It costs about 3 challenge cars to have done but I always thought it should be doable with an acid or base spray on application one section at a time.

You would have to be nucking futz to go to those lengths to save a few ounces though.

Just take a good schit before the auto-x and you will likely be a little ahead of all that work to get the last bits out.

I'm not so much doing the removal for weight as the seam welding. Can't weld undercoat. However, I also wanted it to look good.

How does the dry ice work on something like a wheelhouse or vertical surface?

In reply to JohnRW1621:

Nope. Options c-z are whatever you want to call me.

Are you removing it to facilitate welding? The only thing I've read and it's been said here already is dry ice

You might want to try a pneumatic scaler for the tight spots.

Once you mush it into the seams with a wire wheel it's not coming out until you weld. Then it will all come out and screw things up. Yu can use dry ice everywhere if you build a rotisserie. I can't believe you don't have the car on one yet.
Welding inch on inch off should add as much stiffness as the rest of the sheet metal can handle. Think hard about what seams need to be welded, probably not all of them. A cage that is tied in properly will add way more than seam welding.

See If you can find someone who does cryoblasting. Basically they substitute the aggregate for dry ice.

Otherwise dry ice and a needle Scaler may be more budget friendly.

Kill it with fire

practical demo

https://www.youtube.com/embed/NidF0yHMXt0

My 2 cents is one inch on, one off, if that, all done in tacks that you can hold your bare hand on before doing one next to it. Oh yeah, support the car on either its wheels, or at 4 jacking points-ask me how I know. The video NOHOME posted looks like about your best bet on digging out seam sealer. Again, ask me how I know. Good luck!

I keep hearing about using a liquid nitrogen "death ray" to blast that stuff off. Makes dry ice look like amateur hour.

Knurled wrote: I keep hearing about using a liquid nitrogen "death ray" to blast that stuff off. Makes dry ice look like amateur hour.

That sounds like something I need

Find the ounces and the pounds will come.

I used a propane torch and it worked just fine to remove that stuff and you don't need a rotisserie, but it will help reduce flaming hot debris falling on you.

leave ur seams alone, they're not bothering u

Huckleberry wrote: You acid dip the whole chassis then quickly rinse and paint. It costs about 3 challenge cars to have done but I always thought it should be doable with an acid or base spray on application one section at a time.

And that's how the Spirit ended up needing a vinyl top.

NOHOME wrote: Kill it with fire practical demo https://www.youtube.com/embed/NidF0yHMXt0

So, in all seriousness, why is the weed burner a bad idea?

And, best application of heat: hit and scrape while hot, or kill it with fire and come back after it cools with the oscillator?

In reply to wheels777:

So how are you doing it?

This becomes one of those "if you have the time to do it, do it" situations.

All answers are correct. To remove seam sealer you will use heat, dry ice, scaler, wire wheel on angle grinder, scraper, blood and occasionally tears.

I'll have a beer for you tonight.

Knurled wrote: I keep hearing about using a liquid nitrogen "death ray" to blast that stuff off. Makes dry ice look like amateur hour.

Head on over to rallyanarchy.com and search for it. If you have thin skin, I wouldn't advise going to RA.