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  View original topic: Dustless Blasting Experience
Semper_Dad Tue Aug 11, 2020 10:05 pm

Subject is a 1974 VW Model 181. AKA Thing, Safari, Kubel
Originally Sunshine Yellow but received a black respray by previous owner some time ago. I would say it was of “Macco” quality. I have had the vehicle for about 10 years. No major visible signs of damage or rust. “Macco” paint job was beginning to show it’s age.

Engine fire several months ago is what initiated the rebuild. Inlet tube on carburetor popped out.
Most of the fire damage was contained to the engine bay and rear deck cargo area. All wiring, rubber and plastic parts were totally incinerated. Generator, carburetor, coil, fuel pump was destroyed beyond repair. Distributor was able to be rebuilt. Engine appears to not have ingested any burnt bits or water from being extinguished. Engine torn down to longblock and restored. Now waiting re-installation.

Initially, I was going to only repair the damaged items. As I tore down the rear of the car it was decided to go ahead with a full “body-on” restoration/repaint. A “body off” restoration is beyond my resources. I was never fond of the black and wished to go to a non-stock lighter color.

Vehicle’s body was totally disassembled. Fenders, doors, hood, decklid, and airboxes removed. All wiring was removed to be replaced with new harnesses. All rubber parts were removed and evaluated. Most will require replacement

Contacted a local Dustless Blasting operation for a quote to blast exterior and interior shell including engine bay and trunk area. Initial quote was close to $1300. As I had already had the fenders, hood, decklid, and airboxes traditionally sandblasted, a new negotiated price came to $750. This amount was based on an estimate of 4 hours work. Their normal rate is $175 per hour. I agreed to do the cleanup afterward. Operations was to be done in my driveway which is triple wide.

Day before scheduled blasting date; I prepped the car. Fuel tank cavity was covered with plywood to protect front suspension area. Transaxle was bagged and padded. Brake hoses and any soft bits were also padded. Car was centered in driveway as to give operator plenty of room to move around vehicle.

Before blasting began, I briefed operator as to where and what to avoid.

Media was an exceptionally fine crushed recycled glass. Operator stated the material was eco-friendly and had a low silica content. Media resembled fine white powder sand.

Let me first start off by saying that “Dustless Blasting” is anything but “dustless”. It may be less dust than traditional blasting, but definitely not dustless. A more representable name would be “Wet Blasting” as it uses water and high-pressure air. The water, in theory, reduces the chances of warpage due to friction of the media material and metal.

Operation took a little over 3 hours. Did not receive any credit for time not used. After blasting, a rust preventative solution was applied via water hose to temporarily reduce any flash rust. Allegedly should last at least 72 hours.

Quite a bit of blasting media was in and around the car. Several inches in some places. Most of it was immediately around the car and there were traces of media some 20-25 feet away. At least an inch of media had collected on the floor pan from the interior blasting. Wet media had the consistency of cement. Once dry, it easily fell apart. A layer of wet media was stuck to various parts of the car. When wet it could be scooped up with a shovel. Once dry, media could be carefully swept, blown, or vacuumed. In some places it could be blown away with air, other places required some direct brushing. I have recovered some 5-6 cubic feet of media from inside and around the car so far.

One of the big issues was a lot of the media stuck to the car when it was wet. Could not use a power washer as it would compromise the rust treatment applied earlier. Only option was to let it first dry and then brush it off. This dusting was all over the car, even areas that were not blasted. Voids needed to be blasted out with air. It was easy enough to remove, just very time consuming. I have currently spent about 6 hours in media removal. Probably have another 3 or 4 hours. Once all the media is removed primers will be applied. Blasting did reveal some known and unknown damage and one small rust through.

“Dustless Blasting” is highly effective at removing paint, primer, body filler and some rust. My biggest heartache with dustless blasting is the mess and cleanup. I do not recommend “dustless blasting” unless you are doing a “body off” resto. This way you have easier access to all parts of the body for the inevitable cleanup. Also, there is less likelihood of creating collateral messes in non-blasted areas. When wet, the media sticks to everything and gets tracked everywhere. Do not recommend doing this at your home. The mobile aspect of “Mobile Dustless Blasting” sounds convenient but really needs to be done somewhere better suited.

Enjoy the video




Recovered media in and around car (approx 5-6 cubic feet)


PuddleRainbow Wed Aug 12, 2020 5:22 am

Holy moley....

chrisflstf Wed Aug 12, 2020 5:05 pm

Interesting, do they offer cleanup options? Even sandblasting, more time is spent cleaning up. Nothing like having a beach in your driveway

Q-Dog Wed Aug 12, 2020 5:22 pm

You'll probably never get all of it out of the car.

68IHscout Wed Aug 12, 2020 8:09 pm

Dry ice blasting ,the only thing you would clean up is the dislodged material.

keegs Wed Feb 10, 2021 5:56 am

Took me a week to do two doors with many applications of an eco friendly chemical stripper.... Lots of down time waiting for the stripper to do its work... still need to wire brush the tight spots.

A day of blasting and cleanup sounds good. I'm thinking I'd need to coordinate the cleanup work with the painter so there's no surprises.

Thanks for sharing.

FritzCP Thu Feb 11, 2021 11:25 am

maybe rent a Uhaul trailer for a day just and take it to the blasting facility? Even if a couple hours away, sound like the savings in cleanup would be worth it. Maybe they would let you power wash all the media residue off immediately after the blasting but before applying the rust inhibitor?

keegs Thu Feb 11, 2021 2:54 pm

FritzCP wrote: maybe rent a Uhaul trailer for a day just and take it to the blasting facility? Even if a couple hours away, sound like the savings in cleanup would be worth it. Maybe they would let you power wash all the media residue off immediately after the blasting but before applying the rust inhibitor?

I read earlier somewhere that the operation was very loud and I live in a quiet residential area. So when I spoke to the guy he said I could bring the car to his shop to get the work done. I was surprised to see how much medium was used.

Busbodger Mon Apr 05, 2021 2:03 pm

FritzCP wrote: maybe rent a Uhaul trailer for a day just and take it to the blasting facility? Even if a couple hours away, sound like the savings in cleanup would be worth it. Maybe they would let you power wash all the media residue off immediately after the blasting but before applying the rust inhibitor?

Added bonus, the ride home might blow out some spare media.

I would recommend a body off rotisserie blast so the body can be turned over and dump out the voids. Minimize the amount of compressed air and vacuum time necessary.

Exaktaphile Mon Apr 05, 2021 4:02 pm

I had the bottom of my shell dustless blasted a few years ago and found a shop near me that came to my house and picked up the car. I followed and watched the work. The guy siphoned a solution into the blasting water that's named "Hold Tight". It does a great job of preventing flash but make sure you keep everything garaged while working with naked metal. The media was crushed glass. The water pressure was 150psi, which he told me is necessary because of the low friction properties of the water/media mix.

When they finished blasting, there was media everyyyyyyyyywhere. The guy turned the media valve off and rinsed the whole car (with h20/Hold Tight) to remove virtually all stray media. When I got the car home, there were only a few hidden areas of wet media that needed brushing for removal. As the OP discovered, the cleanup part of the dustless experience is a very important step so don't skip it.

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