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JMarsa
02-25-2008, 09:21 AM
In the next few weeks I'll have the bottom of my Nova blasted. I've got some welding to do and want a clean surface that I'll paint later. There's no rust, but lots of dirt caked on from the years.

What's the best media to use? One local guys only uses steel shot, another sand and Eastwood carries: Aluminum Oxide & Silicon Carbide.

Thanks,

--JMarsa

MrQuick
02-25-2008, 06:36 PM
My local guy uses medium sand for the frame and undercarrige and AO for top, interior and body parts to avoid warpage.

rubadub
02-25-2008, 08:36 PM
I use sand on the undercarriage and the frame also, this stuff here, Its $7 a hundred lbs.
https://static1.pt-content.com/images/noimg.gif

I also would like to mention, that I don't even get around this sand without supplied air, and supplied air until everything is blown out and cleaned up.

Rob

JMarsa
02-26-2008, 05:21 AM
Thanks for the replies. So looks like I'll go with sand.

Here's another concern. My interior is mint, I mean MINTY FRESH. Little ol' lady car, less than 50K, stored inside. I'm not taking anything out since it's so clean and tight. What's the best way to keep the blasting media out of the car? If I use foam tape around the doors and trunk and tape off the outside cowl and the kick panel vents inside would that cover it? Any other ideas?

--JMarsa

rubadub
02-26-2008, 09:30 PM
You could tape up everything that looks like sand might get in, then get inside the trunk and inside the car, have some body with an air gun get under there and start blowing air at it, see if you detect any air getting in. Just a thought.

Rob

JMarsa
02-27-2008, 12:31 PM
Guess I could though an old car cover over it as well.

--JMarsa

the camtender
02-27-2008, 02:27 PM
glass beed

JMarsa
02-27-2008, 06:34 PM
glass beed

Are you serious? I didn't think glass beads had any "bite". Plus isn't it a media you would want to recycle to use it several times? You must have mentioned it to keep the dust down?

--JMarsa

Aguila1
02-27-2008, 07:45 PM
I used "Black Beauty" (coal slag) and "Star Blast" (like sand with less harmful silica) to strip my undercarriage. Using normal sand can cause permanent damage to your lungs. Black Beauty is a bit dusty if you reuse it. I would take the interior out or cover everything with poly sheets and tape the openings. It's a messy job.

Greg from Aus
02-29-2008, 02:00 AM
I use sand on the undercarriage and the frame also, this stuff here, Its $7 a hundred lbs.
https://static1.pt-content.com/images/noimg.gif

I also would like to mention, that I don't even get around this sand without supplied air, and supplied air until everything is blown out and cleaned up.

Rob



I can't belive you would use sand,it has been banned in Australia since 1992, that stuff is deadly it can give you silicatosis which will KILL you

MrQuick
02-29-2008, 08:24 PM
yep, not a great way to gain weight either. I hope you are using air supply....oh you are. Just re read you post.

rubadub
02-29-2008, 09:47 PM
I can't belive you would use sand,it has been banned in Australia since 1992, that stuff is deadly it can give you silicatosis which will KILL you

This is me in an SAS supplied air setup, Like I mentioned earlier, I don't even get near this sand with out this on, I also do all my grinding and clean up with supplied air on.

http://www.1969supersport.com/restore7.html

Rob

rubadub
02-29-2008, 09:54 PM
I keep the supplied air pump in my house, the lines are buried 7 feet down in the ground, if I have to change out a supplied hose, I just fish it out and put another one in, although I haven't had to do it yet, but I checked it all out before I filled the hole in.
Sand blasted metal is as good as it gets, sand will get the rust off and all you have to do is blow the metal off clean, don't need to touch it, just spray the epoxy right on it, it sticks like its welded on.

Heres the pump in the house.

http://www.1969supersport.com/paintroom05.html

Rob

rubadub
02-29-2008, 10:03 PM
I can't belive you would use sand,it has been banned in Australia since 1992, that stuff is deadly it can give you silicatosis which will KILL you

I'm sure you didn't see where I mentioned supplied air for the first picture of the sand.

Heres some stuff i wrote up, that might be helpfull.

http://www.1969supersport.com/respirators.html

I also use a pretty big bead blaster, I use supplied air to fill it, clean it, use it, clean the parts afterwards, and clean up the work area.

I won't open a bag of sand without supplied air on.

Rob

rubadub
02-29-2008, 10:07 PM
All these pictures I have putting on were taken a while back, you can see where I talked about supplied air, heres the bead blaster.

http://www.1969supersport.com/dog5.html

Rob

John510
04-08-2008, 07:04 PM
The guy that did my car used Garnet.

opnwide
05-21-2008, 06:21 PM
I had my whole car blasted with plastic media. It worked great on undercarriage, but did not remove 100% of sealer. The rest was no problem, though. Nice finish.
Almost a year later and almost ready for paint,,,I am still finding media though in the cracks, in the rockers, etc. Fortunately, this stuff will NOT absorb water like sand will. I don't know how many times I've blown out the car. You can never get rid of all of it. Think about that before using sand.

rubadub
06-03-2008, 09:55 PM
On page 7 of this http://www.1969supersport.com/restoration.html you can see a tool, it will get the sand out of a chevelle, but it takes a lot of air pressure, anyway it works.

Rob

MonzaRacer
08-31-2008, 12:51 PM
Natrium 260 basting soda.
Give Chesapeake Bay Blasting a call ,I try to look up their number as was thinking of getting into soda blasting last year,,, still thinking of it.

minendrews68
10-18-2008, 07:01 PM
rubadub, where did you get the air pump, and about how much?

Thanks,
carl

rubadub
10-24-2008, 10:09 PM
I bought it a few years ago at our local car quest store, around a $1000.00 with two fifty foot hoses and some hoods.

To say i like it would be an understatement, I love it, use it for everything, even sprayed my three little apple trees.

Heres one here.

http://www.sjdiscounttools.com/sas9800-18.html

Rob

JMarsa
11-10-2008, 02:27 PM
*UPDATE* with another question...

So I checked out the local shops (all about the same price) and have the choice of the following media types (descriptions pulled from the net, not my a$$):

1. Urea is a plastic grain stripping abrasive used in sandblasting operations. It is the most widely used plastic media. Urea is environmentally friendly and recyclable - an alternative to chemical stripping. Urea is formulated to meet an increased level of stripping performance where stripping speed outweighs other considerations. Urea is able to strip tough coatings with an impressive strip rate. Urea is typically used for less sensitive applications. Standard mesh sizes 8-12, 10-20, 12-16, 16-20, 20-30, 30-40 and 40-60. Sizes 12-20, 20-40 and 60-80 can be specially ordered. Packaged in 50 lb boxes or bags or 250 lb drums.

2. Starblast™/Sand is a general-purpose staurolite abrasive used in steel fabrication and bridge maintenance to remove rust, mill scale, and weathered coatings

3. Steel grit blasting is ideal for aggressive cleaning applications. Steel grit will quickly strip many types of surface contaminants from steel and other foundry metals. Steel grit is softer than aluminum oxide and does not fracture as easily, making it ideal for aircraft and aero-space applications. The angular nature of steel grit produces an etched surface on metal for superior adhesion of paint, epoxy, enamel, rubber and other coatings.

So the question is, for a car with solid floors that was Ziebart'd when it left the dealer and spent 10 years on dirt roads, which one is best?

--JMarsa