I’m writing in hope of mining some experiences, opinions, and/or advice on the subject of completely stripping a chassis in preparation for metalwork. There’s really two topics I am researching.
Dipping versus media blasting – and coatings/rust preventative measures.
I’ve been looking into these basic technologies to strip and prep my car for chassis repair. And I’ve been surprised by a few details that makes me scratch my head a bit.
Media Blasting:
I’ve been speaking with a local company that specializes in stripping car restoration projects. They would use plastic media to limit heat in the panels, especially the larger panels like the hood, roof and deck lid. They then do “touch-up” of tenacious areas with oxide media. One of the things that shocked me was that they said their blasting is ineffective at removing the undercoating (or any other rubberized or similar coatings). As such, I’d need to remove this myself first. And, of course, they can only strip areas that their blast media can be aimed at. In other words, it does not strip the inside of the frame tubes, the inner layers of the rockers, or even areas between the panels and any inner bracing (hood, deck lid, doors, etc). The cost for this service is the better of the two options as follows: $1,200 to $1,500 for the shell, $180 each for the doors, $180 for the hood, and $120 for the deck lid. They then offer to spray everything in epoxy primer for another $800. So, roughly $2k for stripping (most of the surfaces), and $800 for a protective coating.
https://www.u-spray.com/
Dipping:
With this method, I’ve learned a lot. I am speaking with the place that does stripping for The Werk Shop, which I think is a vote of confidence. What I’ve learned is that they first dip the chassis/parts in a heated base solution. This is what strips everything off the metal. They tell me it removes paint, filler, undercoating – everything except metal. They then rinse and dip in an acid solution. The acid neutralizes the base and removes all rust. They tell me their process removes no metal, although I just reduced a vixen file to the thickness of a beer can in a phosphoric acid solution a few weeks ago by accidentally leaving it in there for a couple of weeks. So I assume the acid removes “some” metal. But likely not much. Note that this process removes rust from everywhere including the hidden nooks and crannies. And I don’t have to remove the undercoating. The process costs a bit more at $2,000 to $2,500 for the chassis and about $1,200 for the rest of the parts – about $3,300 total. Then they apply a water soluble coating that protects the bare metal from flash rust. They tell me this will not protect the metal forever. But I wonder if it is enough for the car to live in my ridiculously dry shop while I work on sheet metal. They offer an e-coating as a much higher level of protection. It comes out gloss black and would protect everything thoroughly. Shockingly, they say that the e-coat is the one thing they dipping process can’t remove! This e-coat is expensive, roughly matching the cost of the stripping process.
http://www.metal-cleaning-rsi.com/
As you can probably tell by reading into my summaries, I am leaning towards the dipping process as it does a more thorough job of removing rust and corrosion from everywhere. I’d love to learn if anyone has any recommendations or cautions. And I’d also welcome input on the water soluble protection versus the e-coat. Honestly, the cost of the e-coating really blows the budget. But if it is absolutely the right/best thing to do, I’d like to (need to) hear that.
Thanks for your input!
Dipping versus media blasting – and coatings/rust preventative measures.
I’ve been looking into these basic technologies to strip and prep my car for chassis repair. And I’ve been surprised by a few details that makes me scratch my head a bit.
Media Blasting:
I’ve been speaking with a local company that specializes in stripping car restoration projects. They would use plastic media to limit heat in the panels, especially the larger panels like the hood, roof and deck lid. They then do “touch-up” of tenacious areas with oxide media. One of the things that shocked me was that they said their blasting is ineffective at removing the undercoating (or any other rubberized or similar coatings). As such, I’d need to remove this myself first. And, of course, they can only strip areas that their blast media can be aimed at. In other words, it does not strip the inside of the frame tubes, the inner layers of the rockers, or even areas between the panels and any inner bracing (hood, deck lid, doors, etc). The cost for this service is the better of the two options as follows: $1,200 to $1,500 for the shell, $180 each for the doors, $180 for the hood, and $120 for the deck lid. They then offer to spray everything in epoxy primer for another $800. So, roughly $2k for stripping (most of the surfaces), and $800 for a protective coating.
https://www.u-spray.com/
Dipping:
With this method, I’ve learned a lot. I am speaking with the place that does stripping for The Werk Shop, which I think is a vote of confidence. What I’ve learned is that they first dip the chassis/parts in a heated base solution. This is what strips everything off the metal. They tell me it removes paint, filler, undercoating – everything except metal. They then rinse and dip in an acid solution. The acid neutralizes the base and removes all rust. They tell me their process removes no metal, although I just reduced a vixen file to the thickness of a beer can in a phosphoric acid solution a few weeks ago by accidentally leaving it in there for a couple of weeks. So I assume the acid removes “some” metal. But likely not much. Note that this process removes rust from everywhere including the hidden nooks and crannies. And I don’t have to remove the undercoating. The process costs a bit more at $2,000 to $2,500 for the chassis and about $1,200 for the rest of the parts – about $3,300 total. Then they apply a water soluble coating that protects the bare metal from flash rust. They tell me this will not protect the metal forever. But I wonder if it is enough for the car to live in my ridiculously dry shop while I work on sheet metal. They offer an e-coating as a much higher level of protection. It comes out gloss black and would protect everything thoroughly. Shockingly, they say that the e-coat is the one thing they dipping process can’t remove! This e-coat is expensive, roughly matching the cost of the stripping process.
http://www.metal-cleaning-rsi.com/
As you can probably tell by reading into my summaries, I am leaning towards the dipping process as it does a more thorough job of removing rust and corrosion from everywhere. I’d love to learn if anyone has any recommendations or cautions. And I’d also welcome input on the water soluble protection versus the e-coat. Honestly, the cost of the e-coating really blows the budget. But if it is absolutely the right/best thing to do, I’d like to (need to) hear that.
Thanks for your input!
