View Full Version : Sandblasting the rust.

02-01-2004, 09:49 PM
Okay, I am finally ready to sandblast the underside of my 61 Alpine. I know there are several grades of Sand. Some people tell me to use #20 and others say #70. Neither of them have ever blasted a car so I am not sure. Anyone know what I should be using.

02-02-2004, 02:22 PM
Hello Rob,
the one thing you should not use is sand. As I understand it it is very hazardous to your health.
What are you planning to use to do the 'sandblasting'. If you are thinking of using a small blast gun and a home compressor you are in for a very long and tedious job.
Sandblasting is an excellent way of cleaning rusty metal, and on the underside is unlikely to cause the distortion problems you may encounter on doing outer panels. You need to talk to a professional blast cleaning contractor, in my opinon.

Alec graemlins/thirsty.gif

tony barnhill
02-02-2004, 03:03 PM
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>you should not use is sand. As I understand it it is very hazardous to your health<hr></blockquote>

Uh-oh, all those beach volleyball babes are walking dead & don't even know it! Guess I'll not take anymore beach vacations - anybody wanna buy a condo cheap?

02-02-2004, 07:57 PM

www.bestofblasting.com/ (https://www.bestofblasting.com/)

Has a thread on this:

"Dear Peter,
using sand for blasting is in most countries strictly forbidden by law because of the danger of silicosis. While blasting the sand particles will be broken and silica comes free which is very harmfull for the longs. Only zircon sand which does not contain free silica may be used for blasting but that is quite expensive."

Guess you'll have to leave the bucket and spade at home... and just sightsee at the beach.

[ 02-02-2004: Message edited by: JamesWilson ]</p>

tony barnhill
02-02-2004, 09:06 PM
D@MN! Now there's an OSHA for sand blasting? What's the world coming to? Next somebody's gonna tell me I can't grind the original paint off one of my old cars!! Well, somebody better tell all the businesses out there who are still using sand!

02-07-2004, 10:35 PM
I have an 80 Gallon Two Phase compressor with a small pressureized pot blaster. I wear a hood with a resperator inside to keep the air clean. I also have a fan at the door to keep the dust down.
I blasted (with silica sand) for 3 hours today. Only blasting the bottom of the car and the floor boards. About 1/3 to 1/2 done. I figure another 4-5 hours and I will be done with that job.

02-27-2004, 06:47 PM
A good friend of mine that restores cars told me when sandblasting to remember the speed limit, use at least 55 grade sand at 55 psi. (This was whent the speed limi t was 55 of course. I had to special order the sand to get it that fine. Anytime you sand blast you need to wear a supplied air respirator or hood. The quality of the supplied air is important too, as you don't want to use air straight from your air compressor. It needs to be thoroughly filtered and cleaned. Sand is deadly for sure. I sandblasted my entire Spitifre with a siphon blaster. Took a long time. I was sure I stood up wind and wore a halfface respriaator, googles and hat. That sand will get EVERYWHERE.

Mark Beiser
02-28-2004, 02:44 AM
I wouldn't use silica sand, even with the best protective gear in the world. The stuff gets all over and is still lurking about when the project is over.

For a few $ extra you can get abrasives that don't have the potential to kill you 10 years after using them.

Engineless Alpine
04-28-2004, 04:33 PM
As a geologist and an environmental scientist, I can say don't take everything you hear too seriously.

Most sand is composed of quartz grains eroded from rock. Quartz is the most resistant, both mechanically and chemically: practically inert. Quartz is SiO2 (silica). So of course breaking down sand grains will release silica. That which affects one's health are any small particles becoming lodged in the lining of one's lungs. This could be coal dust (black lung), sand (silicosis), or even flour (miller's lung).

Wear a respirator.

Bruce Bowker
04-28-2004, 07:16 PM
There are numerous types of sand but most assume it is silica. I sand blast a lot but it is almost all limestone (coral) based sand. Not available in the US I would guess and far from the best media but free for me.

There are many types of media for blasting, from walnut shell to glass beads. Regardless, as said, where a good respirator. And expect the media to get everywhere. Lots of cleaning up on the parts afterward, plus your clothes and whatver area you are in.

04-29-2004, 08:36 AM
No need for conjecture, here's the "bible" on use of sandblasting. And yes, it's extremely dangerous to our health, no ifs, ands, or buts about it:


If the link doesn't work, just go to osha.gov and type in "sand blasting".

What's the car worth to you? Your health?

I hope this helps!

04-29-2004, 09:14 AM
I especially recommend topic #6 on the above OSHA link. It explains that there is NO safe kind of sand to use, and OSHA eqates sand with silica. In other words, sand = silica to OSHA.

Lots of folks perform sandblasting and don't become ill. But, it's good to know the facts about the potential hazards before you decide to do it.

Good luck, and be safe!

Engineless Alpine
04-29-2004, 09:52 AM
I think that my post may have been somewhat misinterpreted. Sure breathing silica is bad. So is breathing a myriad of other substances. Make sure that you are protected. Those dead guys in the listed study were simply not well enough protected.

Bruce Bowker
04-30-2004, 07:50 AM
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by vagt6:
sand = silica to OSHA.

I will still argue that not all sand is silica. But OSHA is corerct in their safety warnings regarding silica.

04-30-2004, 09:08 AM
SAND BLASTING, OSHA, county restrictions, spare me. I have a pal who works for the DEQ, we have discussed this BS before. He has yet to explain all the dirt roads in the heat of summer to me yet. A drink of water is hazardous to your health,if you were to be dropped in the middle of Lake Michigan to get it.That being said those of you with you heads stuck in the sand are at most risk, and not from silicosis. Some days I just can't take it. Who wants to take on the RADON argument? By the way, does this hurt my chances of being appointed a diplomate to somewhere

05-25-2004, 08:35 PM
be careful with sandblasting only use it for rigid parts because the metal of the body at this time was quite soft, if you plan to do it let a professional do it to avoid twists and bubbles, otherwise you will need a lot of epoxy filler afterwards, there are also very few specialists who do it with fluid nitrogen thats the best way for the soft parts...

Bruce Bowker
05-25-2004, 09:03 PM
with fluid nitrogen

[/ QUOTE ]

Never heard of that. Can you give a brief idea what that is? I know fluid and I know nitrogen but not together.

05-26-2004, 02:17 PM
nitrogen that what is hat air consists of for 80% chemical: N2, with fluid i meant liquid (sorry i am not a native englishspeaker)
if you make it very cold it gets liquid (at around -180 degrees Celsius)
liquid nitrogen is perfect to take rust, colour etc. away without having rests of the "abrasive" material in your car, so no sand everywhere and of course when you use it on metal you dont loose metal material like you do with sand (if you use sand on e.g. a bonnet you get lots of little craters, i.e. either you need a pound of filler or you can throw it away because it is partly bended)
the liquid nitrogen is quite a new technique for de-rusting cars but already very common in industrial use
i read an article about it in a german veteran car magazine some months ago, i will try to find it, scan it and post it

Ed Wynne
05-26-2004, 06:16 PM
Ssunbeam is correct on the use of liquid N2 for jet cleaning, it is very common in industrial machine shops as it can be done without respirators and leaves absolutely no residue other that that was removed from the work piece.
I seem to recall, that another technique using "Dry Ice"
otherwise called "Solid Carbon Dioxide" for our english as a second language friends.