CRG Discussion Forum

Camaro Research Group Discussion => Restoration => Topic started by: chris69ssx11 on October 08, 2013, 04:03:17 AM

Title: Sand blasting... Chassis
Post by: chris69ssx11 on October 08, 2013, 04:03:17 AM
Hi,
Has anyone ever sandblasted the under carriage (chassis) of their Camaro without taking it apart?

Anyone from Connecticut who can suggest a sandblasting business?
Title: Re: Sand blasting... Chassis
Post by: 69Z28-RS on October 08, 2013, 04:06:36 AM
People have probably done it, but I'd bet they regretted it also.. :)  I would not recommend that.
Sand goes *everywhere* and is not controllable very precisely when you are sandblasting.   You can protect items by applying two layers of duct tape, but that would take you longer than disassembly probably.   We'll see if you get any positive responses on this. :)
Title: Re: Sand blasting... Chassis
Post by: JohnZ on October 08, 2013, 06:02:25 PM
I can't IMAGINE sandblasting any part of a completed car or chassis - sandblasting is an incredibly destructive and irreversible process, and can eat through car sheet metal in a heartbeat. Don't do it!  :o
Title: Re: Sand blasting... Chassis
Post by: Sauron327 on October 08, 2013, 09:55:54 PM
I blast bodies prior to restoration. If you know what you are doing, panels will not get destroyed or warp. What is wrong with the belly that you think it requires blasting? If it's rotten, the car needs more than a blast. Blasting an assembled car is not the best procedure.
Title: Re: Sand blasting... Chassis
Post by: jacmac on October 08, 2013, 10:58:10 PM
Has anyone heard of "Ice Carbon Blasting" I tried it on a 73 camaro I restored last year.Basicly what it does is freeze the crud off your car.I just did the under carriage.It turned out pretty good & most of the original primer was still intact.Also there was very little mess only the crud that was on the car.I was happy.
Title: Re: Sand blasting... Chassis
Post by: chris69ssx11 on October 14, 2013, 03:09:17 AM
Okay... Thanks all for your replies...
New question...
What is the best way to clean up some surface rust on the undercarriage and chassis... wire brushes and wire wheels don't do a good enough job... many nooks and crannies and hard to reach areas.
Any suggestions?  Thanks.
Title: Re: Sand blasting... Chassis
Post by: BillOhio on October 21, 2013, 01:54:40 AM
If you want to recoat it, look into por-15 or KBS topcoats. Metal doesn't have to be rust free but I would take scale off.
Title: Re: Sand blasting... Chassis
Post by: 69Z28-RS on October 21, 2013, 03:53:01 AM
Once you've sanded, scraped, etc.  as well as you can to remove loose rust, Dupont MetalPrep (or similar, such as Jasco) etc can be used to prep the metal for primer and paint...  This is an phosphoric acid which will convert light remaining rust to a different oxide which will accept paint.
Title: Re: Sand blasting... Chassis
Post by: 69RSZEE28 on November 22, 2013, 06:00:47 AM
soda blast it. sodium bicarbonate (baking soda) works extremely well.
Title: Re: Sand blasting... Chassis
Post by: tom on November 25, 2013, 07:02:06 AM
I thought soda blasting wasn't supposed to take down rust.
Title: Re: Sand blasting... Chassis
Post by: 69Z28-RS on November 25, 2013, 03:29:22 PM
That's my thought as well, although I've never actually did it myself.  I'm under the impression that the soda is immersed in water, and that you're 'blasting with a soda/water solution' which abrades away paint, but I would not want to use water to 'blast away rust'..??  Just my only partially informed thought....
Title: Re: Sand blasting... Chassis
Post by: BULLITT65 on November 26, 2013, 05:49:31 AM
Are we just talking mostly the front sub-frame? or can you provide any pics?. A picture on the CRG is worth a thousand (helpful) words. The more detail we have the better we can help you most of the time.
Title: Re: Sand blasting... Chassis
Post by: Sauron327 on November 26, 2013, 10:58:56 AM
Once you've sanded, scraped, etc.  as well as you can to remove loose rust, Dupont MetalPrep (or similar, such as Jasco) etc can be used to prep the metal for primer and paint...  This is an phosphoric acid which will convert light remaining rust to a different oxide which will accept paint.
Acids prior to the use of epoxies is not recommended by some paint manufacturers. Best to follow the TDS for the paint being used. What applies to one paint does not apply to all.

soda blast it. sodium bicarbonate (baking soda) works extremely well.
Post soda prep is vital to paint performance. Failure to do so can lead to fallure.
Title: Re: Sand blasting... Chassis
Post by: Charley on November 26, 2013, 03:07:50 PM
If you are talking about just removing rust. Get some safest rust remover, a plastic tarp or kiddie pool, a fountain pump, short section of garden hose with a spray nozzle. Basically you are washing all the rust away, leaving bare metal, orig paint markings etc will still be there. Not expensive and not abrasive like blasting etc. Will be rust free in several hours. Basically you put the pump in the bottom of the pool or tarp that is sloped to flow the liquid back to the pump. The spray nozzle showers the area you want treated. You don't need to be there all the time, just come back once in awhile and re position the spray nozzle. It really is amazing. http://safestrustremover.com/
Title: Re: Sand blasting... Chassis
Post by: Charley on November 26, 2013, 03:09:56 PM
http://safestrustremover.com/before-after2.asp?B=shock-b&A=shock-a&btext=Inside%20view%20of%20brake%20caliper%20assembly%20%20,notice%20emergency%20brake%20cable%20spring%20and%20rubber%20selve%20on%20cable.&atext=Notice%20overall%20condition%20of%20hardware%20after%20rust%20removal.
Title: Re: Sand blasting... Chassis
Post by: Charley on November 26, 2013, 03:12:06 PM
http://safestrustremover.com/before-after2.asp?B=axel-b&A=axel-a&btext=Complete%20assemblies%20can%20be%20done%20in%20place%20with%20simple%20preparation%20for%20recirculation%20of%20product%20over%20surface%20areas.&atext=No%20disassembly%20required.%20As%20good%20as%20new,%20like%20the%20day%20it%20left%20Ford%20Motor%20Company.without%20turning%20a%20wrench. (http://safestrustremover.com/before-after2.asp?B=axel-b&A=axel-a&btext=Complete%20assemblies%20can%20be%20done%20in%20place%20with%20simple%20preparation%20for%20recirculation%20of%20product%20over%20surface%20areas.&atext=No%20disassembly%20required.%20As%20good%20as%20new,%20like%20the%20day%20it%20left%20Ford%20Motor%20Company.without%20turning%20a%20wrench.)
Title: Re: Sand blasting... Chassis
Post by: 69RSZEE28 on November 26, 2013, 04:58:45 PM
I thought soda blasting wasn't supposed to take down rust.
Little surface rust when its used with water. If its pretty rusty then use sand or something more aggressive than soda. My buddy has a professional blaster and he blasts high end cars! Ferraris, Porsche, Rolls Royce, Corvettes, etc. The soda is so gentle but works great, especially those fiberglass bodies.
Title: Re: Sand blasting... Chassis
Post by: 69Z28-RS on November 26, 2013, 05:57:47 PM
I thought soda blasting wasn't supposed to take down rust.
Little surface rust when its used with water. If its pretty rusty then use sand or something more aggressive than soda. My buddy has a professional blaster and he blasts high end cars! Ferraris, Porsche, Rolls Royce, Corvettes, etc. The soda is so gentle but works great, especially those fiberglass bodies.

Yes, on *fiberglass*, either soda or chemical is preferred to remove paint (but fiberglass doesn't rust).. :)   Rust on steel is totally different, and I would not use soda solutions..
Title: Re: Sand blasting... Chassis
Post by: Kelley W King on November 26, 2013, 06:30:44 PM
Just FYI. At my body mans request I had my 77 trans am media blasted for a repaint. Since it was not a body off resto I taped off the dash, removed the interior and bumpers. The engine and drivetrain is fine so I left it in the car. The blasting (did not ask but looks like a plastic sand) did well for paint and rust removal. The media found it,s way into everything, taped off or not. After blowing, vacuuming, and washing many times the stuff is still stuck to wiring, cables, in wire connectors, and to anything that was oily. I had to removed the dash and and clean all wires and connections, ect. It even stuck to the throttle cable which stuck during a wide open burnout. This past weekend after another wash,vacuum and blow, I drove down the road with windows down and it is still coming out of everywhere. Unless I have a shell only or disassembled parts only, it is back to paint stripper for me.
Title: Re: Sand blasting... Chassis
Post by: Sauron327 on November 27, 2013, 12:14:19 AM
Just FYI. At my body mans request I had my 77 trans am media blasted for a repaint. Since it was not a body off resto I taped off the dash, removed the interior and bumpers. The engine and drivetrain is fine so I left it in the car. The blasting (did not ask but looks like a plastic sand) did well for paint and rust removal. The media found it,s way into everything, taped off or not. After blowing, vacuuming, and washing many times the stuff is still stuck to wiring, cables, in wire connectors, and to anything that was oily. I had to removed the dash and and clean all wires and connections, ect. It even stuck to the throttle cable which stuck during a wide open burnout. This past weekend after another wash,vacuum and blow, I drove down the road with windows down and it is still coming out of everywhere. Unless I have a shell only or disassembled parts only, it is back to paint stripper for me.

As to be exected by anyone who has ever blasted a car. Why would a professional bodyman suggest such a thing on an assembled car? I used to to do all my own blasting. I now sub it out. The blaster uses sand as did I. If you don't know what you are doing you will destroy panels. The people who use soda and it's post blasting neutralization can keep using it. Other medias are available that do not require it. Suit up with a fresh air respirator, use a commercial blasting setup and you'll get an education about the first step in the resto procedure. It's the worst job about the process.
Title: Re: Sand blasting... Chassis
Post by: 69Z28-RS on November 27, 2013, 12:40:24 AM
I too do my own sandblasting, using a TIP 100 lbs pressure unit and a large commercial compressor, 3/4" air hose, and pressure set to 85-95 psi, and keep the spot moving, esp on sheet metal.   I've never warped my parts, but I have seen cars 'commercially' blasted by people not accustomed to 'autos', that did warp every panel on the car (it takes more pressure and more concentrated blasting' than I choose to do!   And even on totally stripped down  body hulls and frame components, the sand STILL GETS everywhere.. and takes time to clean out of the nooks and crannies!   I also have a TIP bead blasting cabinet for smaller parts, where I use either glass bead, or walnut shell particles, and I have used the Metal Rescue type of chemicals? which work well on small clean items.

The process and 'Safest Rust Remover' suggested by Charley seems a viable altenative to stripping rust of even larger items, but I suspect it's like the Metal Rescue chemicals we've all used for rust stripping smaller parts.  With an assembled car, as he's proposed, I'd be concerned about it getting into nooks, crevices, etc..  even if it's 'safe'...?   I might try that sometime though, as the photo results sure looked good *S*