What medium to use?, Soda, Sand, Walnut, Plastic, etc. Options

[Poor-sche Lover]

I have recently gained access to a high quality sandblaster, but I really don't know much about the process. I have a few questions.

1) Do I have to use sand for the blaster, or can I use something else in it? I've heard that you can't use soda because of the way it feeds into the system?

2) I want to use soda because it's less abrasive, but I read that soda will not remove the rust. I definitely need to remove the rust. Which type of medium is best for this?

3) Can you give me any general advantages/disadvantages of soda, sand, walnut, or plastic? Any others that I don't know about?

Any advice/suggestions/info you could provide would be helpful. Nobody around really does this, so farming it out isn't a viable option. It's either this or the long way, and I'd really like to blast if I can. Thanks for your help, guys.

[d914]

i'm going to get the car soda blasted...here is the web site of my local guy...Maybe some info for you..

http://www.nutechsodablasting.com/

[Korijo]

i like medium grit walnut shells. wont get in all the little nooks & crannies like sand..

[Poor-sche Lover]

Will the medium grit walnut shell do anything to potential rust?

[iamchappy]

I've had trouble with the walnut clogging up my blasters.

[Korijo]

QUOTE

Will the medium grit walnut shell do anything to potential rust?

it'll blast it away..

QUOTE

I've had trouble with the walnut clogging up my blasters.

fine grit will clog, but medium shouldn't (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif)

[Poor-sche Lover]

So, you can use the walnut in a "regular" blaster? Where do you get it from? How much would it take to do a whole car?

[Pistachio]

QUOTE (Korijo @ Mar 18 2006, 07:59 PM)

QUOTE Will the medium grit walnut shell do anything to potential rust? it'll blast it away..

Now that's interesting - It was my understanding that the advantages of the "soft" abrasives (wal shells, poly, etc) was that they clean without etching the metal. Hence they're the snitz for cleaning things like delicate trim, machined surfaces, or soft metal parts & for paint removal on large body panels. Because of the media's soft nature, they work without the heat buildup that'll warp body panels ala sand with an inexperianced operator. However, the trade for their nice non-etching nature, is that they absolutely suck at rust removal. (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif)

The guy I know that does poly-stripping for the street rodders & restorers in N. NV, strips the paint off the car using the poly media and then goes back & spot blasts any "rusty" areas with aluminum oxide. (IMG:http://www.914world.com/bbs2/html/emoticons/smile.gif)


Yeah walnut shells will work in "any" blaster. The price depends alot on your supplier/whether or not they sell it all the time or are special ordering it for you & where you are. From my experiance anything in the $0.72-76/lb range is about right. I have no idea how much it would take to blast an entire car, but I wouldn't plan on re-using it much. Which is one advantage poly has over shells if you're blasting in an enclosed space - you can sweep it up, screen it & reuse it. Which justifies it's "twice the price" nature to buy in. On the other hand, walnut shells are bio-degradeable & will disappear into your lawn/yard- the paint won't, but the shells will.

IMO one of the biggest things people underestimate with blasting (in a cabinet or otherwise) is the importance of an absolutely dry air source and the volume of air they're going to need to make themselves happy (& yeah, the media needs to be "dry" too). Dry air is a must to prevent clogging issues & it takes a fair infrastucture to get it that way - one of those little "air dryer" filters that Sears sells hung off your air compressor ain't going to do it! Ya gotta cool it to dry it. And again, JMO, you're going to get bored & disgusted before you get a single fender done if you're going to try and use a little 50CFM single stage 5HP compressor. You need volume to blast effiecantly - CFM not PSI.

Yeah ok, somepeople have more time than money, but I think if I were going to try and blast an entire car - I'd go rent a huge 2000CFM, industrail compressor for the weekend and be done with the car, than spend six weeks trying to do it with my 7hp two-stage.

That's all JMO of course.

[JPB]

If your sandblaster is a preasurized type or just a bucket type, the sand of choice is Black Beauty. It comes in different grain size and is made of compresed cole. Once the BB hits the sheet metal, it becomes finer. A sandbalsted surface will need some glasing putty because of the rough texture. BB is very forgiving and will give you the time to blast frequently on the same spot without eating through your thin guage metal. The easiest place to find it is at an equipment rental place, Sunbelt Rental, United Rental, RSC, that rents sand blasting equipment. If you want the rust to go away, BB is the way ta gooooo; or use the alternative method (IMG:http://www.914world.com/bbs2/html/emoticons/sawzall-smiley.gif) !!!!!

[Poor-sche Lover]

As I read more and more, I am thinking that the best way to go would be to soda blast the whole car, then go back and sand blast on the spots where I'm likely to find rust. Does anybody know how much soda it would take to do a whole car? Can I use the same blaster for both the soda and sand? Isn't a blaster just a huge air compressor with a hose on it? It shouldn't matter, then, should it? Thanks.

Alan

[rhodyguy]

gallons of air per hour and tank capacity of the comp. tool requirements. sometimes you need a different sized nozzles (hole) to handle the different mdia. sand is fine, shells are irregular and larger, i know the plastic media required a special nozzle when i looked into getting a setup a few years back. i figured i could pay for alot of farmed out metal cleaning for the cost of a BIG compressor, and the plastic bead setup. doing this sort of big time body stripping at home makes a mess you won't believe. you def don't want to use your garage to do this. you never really get it clean.

k

[Korijo]

QUOTE (Pistachio @ Mar 19 2006, 04:02 AM)

QUOTE (Korijo @ Mar 18 2006, 07:59 PM) QUOTE Will the medium grit walnut shell do anything to potential rust? it'll blast it away.. Now that's interesting - It was my understanding that the advantages of the "soft" abrasives (wal shells, poly, etc) was that they clean without etching the metal. Hence they're the snitz for cleaning things like delicate trim, machined surfaces, or soft metal parts & for paint removal on large body panels. Because of the media's soft nature, they work without the heat buildup that'll warp body panels ala sand with an inexperianced operator. However, the trade for their nice non-etching nature, is that they absolutely suck at rust removal. (IMG:http://www.914world.com/bbs2/html/emoticons/sad.gif)

walnut shell will get the metal/rusty part well enuff to see what needs (IMG:http://www.914world.com/bbs2/html/emoticons/sawzall-smiley.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/welder.gif) , yet soft enuff to not warp a panel (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) (IMG:http://www.914world.com/bbs2/html/emoticons/smoke.gif)

[iamchappy]

Nozzel and gun size were the factors with my problems with the walnut shells, I have 2 siphon feed blasters and one pressure blaster and am still experimenting with different medias. I like steel grit and aluminum oxide for fine finish but is to expensive for anything
but small surfaces and wheels, I use the black beauty slag for fast cutting but you need to be careful not to overheat and warp steel
panels with it. I like the idea of plastic media but have not tried it yet.

And always there is silca sand cheap available but make sure you dont breath the dust as with the other silica based blasting media.

[Poor-sche Lover]

Apparently, soda does require a special blaster. At least that's what it looks like, so I'm looking at the Black Beauty. It seems like my most economically viable option. Like I said, I already know there's a lot of body filler and such that I'm going to need to get rid of, and I want to find all the rust that I can. JPB, iamchappy, or anybody: do you have any before/after pictures of things you've used Black Beauty on?