Moparts
Sand blasting body parts ??
Posted By: Boise Chall
Sand blasting body parts ?? - 07/02/10 02:09 PM
I have a couple small areas to sand blast on my 73 Roadrunner like behind the back bumper and under the battery tray. I am planning to use silica sand ( yea I know the dangers) my local lowes doesn't have silica sand they have Quartz is it the same stuff???? will quartz work????
Posted By: maximus
Re: Sand blasting body parts ?? - 07/02/10 03:11 PM
If you have a local cement transit company or brick supplies company they usually have silica sand for sale. That's where I get mine.
Posted By: ProStDodge
Re: Sand blasting body parts ?? - 07/02/10 04:08 PM
use extreme care. Sand blasting can easily warp body panels. The more aggressive the media the faster it warps.
Posted By: Stanton
Re: Sand blasting body parts ?? - 07/02/10 05:16 PM
Silica sand isn't readily available for one simple reason ... it's a hazardous material. Without proper breathing equipment the dust will kill you (eventually). Forget the silica, there are plenty of other substrates that will do as good or better of a job and won't harm you.
Posted By: 4BBodies
Re: Sand blasting body parts ?? - 07/02/10 05:31 PM
I use 50 pound bags of Playsand (quartz) from Home Depot. It works great, but I have to sift it. At $2.89/bag the extra few minutes of work aren't a big deal, Black Beauty is like $8.00/bag. As far as body panels, what these other guys said is correct, and only do small areas. Use some type of rust remover for large areas, like Naval Jelly.
Posted By: rxod
Re: Sand blasting body parts ?? - 07/02/10 07:23 PM
I own a media blasting business. We use aluminum oxide in place of sand for rust removal. It is less toxic and you can recycle it many times. Sand shatters into dust after one or two uses and of course it is toxic to the lungs (silicosis). Any media that can remove rust can warp sheet metal. There is a big misconception that heat from sand blasting causes warping. It will get hotter sitting in the sun. It is actually caused by suface peening which expands the metal. It is fine to use it on areas that are ribbed or curved or edges, such as floor pans, jambs, engine compartments, heavy metal,(and bettery trays), as this type of metal has internal support against warping. Never on flat sheet metal. We would blast the back of your bumper and your battery tray for about $30. We'll worth not dealing with the mess and aggrevasion and wear and tear on your compressor. So call a local sandblaster for a quote. As for sand, what ever you use must be super dry or it won't flow in your sandblaster.
Posted By: Boise Chall
Re: Sand blasting body parts ?? - 07/02/10 07:59 PM
I don't need to blast any body panels just a small area under the trunk behind the back bumper it looks like the factory never painted it so it's got some surface rust. Either that or the field mice had anti gravitational wizz. I need to blast under the battery tray also
Posted By: Boise Chall
Re: Sand blasting body parts ?? - 07/02/10 08:06 PM
I had the hood deck lid and valances done by a professional blaster. The area under the trunk is only 10" x maybe 36" the battery tray area is 6"x6" not worth hauling the car 20 miles to get it done. I doubt it will take me 3 hours to do it myself and I get to learn something. Hopefully I don't learn that sand blasting sucks and I should have driven the 40 mile round trip.
Posted By: Stanton
Re: Sand blasting body parts ?? - 07/03/10 07:34 PM
What you're going to learn is that sandblsting sucks and you should have driven the 40 miles !!!
It's messy as hell - the sand gets everywhere and the dust will have the neighbors calling the cops. You'll need a shower and change of clothes afterwards. You'll spend money on a cheap hood that will fog up 10 seconds after you put it on and will be hot as hell. You'll be on and off the nozzle because you can't see what you're doing. Unless you have a BIG compressor, the pressure will drop very quickly and will take longer to remove the rust and paint.
And, if you take some cheapskate's advice and use playsand you'll quickly find that Home Depot doesn't care if its dry or soaking wet - as far as they're concerned its going in a sandbox and doesn't matter. So ... not only do you have to sift it, you'll likely have to wait for it to dry too - what are you going to spread it out on to do that ??? The couple bucks you save on playsand is lost buying or building a sifter.
Posted By: Boise Chall
Re: Sand blasting body parts ?? - 07/03/10 07:59 PM
I already have a sifter (a stainless steel pasta strainer Walmart $7). The cheapy hood came with the cheapy pressurized sand blaster. I have a 7.5 hp two stage compressor on an 80 gallon tank that worked fine when I tested the blaster a month or so ago. I never planned on using play sand because somebody on here said that it's beach sand and it will have salt in it that makes sense to me. the cheapest I was going to go was quartz but I didn't know if it was the same as silica sand but quartz was all that Lowes had I will take a look at home depot and see if they have silica sand.
Posted By: DaytonaTurbo
Re: Sand blasting body parts ?? - 07/03/10 09:54 PM
One thing you will find is a small hand-held wand type sandblaster works, but slow as hell. I hooked one up to my sandblaster thinking I was going to sandblast my whole engine bay. Well I could have, except it probably would have taken 80 years to do it. I did not have a pressure or supply problem, and tried using both a gritty crushed glass as well as a finer silica sand. Both worked but both took a VERY long time to do any appreciable area. I ended up changing to a wirewheel on a drill, die grinder and angle grinder. I just got fed up with how slow, messy and uncomfortable blasting with a small hand held wand is. I did the bulk of the area with wire wheels and just spot blasted the corners/grooves I could not get at with the wire wheels.
Posted By: GregCon
Re: Sand blasting body parts ?? - 07/03/10 10:57 PM
Interesting comment about heat from blasting not warping sheetmetal. I don't know if your comment is true or not but I don't think the bit about the metal getting hotter in the sun offer much prrof.
When a car sits in the sun, it all gets hot more or less evenly and slowly. When you balst, I can easily believe the abrupt rate of heating and the fact that it is localized plays a role - if not all of the cause. Of course, the pressure can't help either.
I have a couple goodsources for blasting near me and they use completely different media (one uses plastic, the other uses common #4 sand) but neither has warped any panels of mine even when I had a whole car done. They know how to do it.
I prefer the common sand as it truly gets you a near white blast with a good anchor profile.
Posted By: 4BBodies
Re: Sand blasting body parts ?? - 07/03/10 11:48 PM
Well, as an accomplished cheapskate, I don't see a problem saving $$$ when the method used accomplishes the same thing. In this case, sand over black beauty. Which is coal dust, by the way, and is NOT much better for your lungs OR the environment. And it really pisses the neighbors off more than sand too! And HD sand has always been dry for me, going on 7 years now. As far as other comments here, if people are too lazy to do it themselves, they wouldn't understand trying to save money anyway. And I don't have the desire $$$ wise to have someone else restore my cars, doing this hobby myself is the point. Yes, sandblasting is a drag, but it doesn't take all that long with good equipment. Why go through all that aggrevation as a contractor, when you can just go buy a finished car to start with? I do it ALL myself, not just the easy/fun parts. Just my
Posted By: Boise Chall
Re: Sand blasting body parts ?? - 07/04/10 12:37 AM
Quote:
Well, as an accomplished cheapskate, I don't see a problem saving $$$ when the method used accomplishes the same thing. In this case, sand over black beauty. Which is coal dust, by the way, and is NOT much better for your lungs OR the environment. And it really pisses the neighbors off more than sand too! And HD sand has always been dry for me, going on 7 years now. As far as other comments here, if people are too lazy to do it themselves, they wouldn't understand trying to save money anyway. And I don't have the desire $$$ wise to have someone else restore my cars, doing this hobby myself is the point. Yes, sandblasting is a drag, but it doesn't take all that long with good equipment. Why go through all that aggrevation as a contractor, when you can just go buy a finished car to start with? I do it ALL myself, not just the easy/fun parts. Just my
Read this article on my 72 Challenger we might have something in common http://www.moparmax.com/features/featurecar/v_5-resurrection-1.html
Posted By: dulcich
Re: Sand blasting body parts ?? - 07/04/10 01:14 AM
Quote:
Well, as an accomplished cheapskate, I don't see a problem saving $$$ when the method used accomplishes the same thing. In this case, sand over black beauty. Which is coal dust, by the way, and is NOT much better for your lungs OR the environment. And it really pisses the neighbors off more than sand too! And HD sand has always been dry for me, going on 7 years now. As far as other comments here, if people are too lazy to do it themselves, they wouldn't understand trying to save money anyway. And I don't have the desire $$$ wise to have someone else restore my cars, doing this hobby myself is the point. Yes, sandblasting is a drag, but it doesn't take all that long with good equipment. Why go through all that aggrevation as a contractor, when you can just go buy a finished car to start with? I do it ALL myself, not just the easy/fun parts. Just my
-dulcich
Posted By: bobs68
Re: Sand blasting body parts ?? - 07/04/10 01:52 AM
What he said!!! I have sandblasted for over 30 years and have done complete cars with sand and soda,The combination of heat from the sand and air pressure will warp panals. Most of the time it's the people that think anyone can sandblast that warp panals.
Posted By: Boise Chall
Re: Sand blasting body parts ?? - 07/04/10 02:37 AM
The guy that blasted the hood, deck lid and valances also blasted my 72 Challenger with silica sand and it came out fine. The guy that owned the company before him did my 92 Vette with walnut shells and he made a major mess of it. Why does it matter if the panels have a little warping in them? if it was media blasted the your going to be doing bodywork anyway what's a little more going to hurt
Posted By: GregCon
Re: Sand blasting body parts ?? - 07/04/10 02:40 AM
Well, a straight panel is a whole lot more likely to look good than a warped one, even after body work. Most people are OK at beating out dents and filling them but it's a whole other world when it comes to getting a warped panel looking right again.
Posted By: rxod
Re: Sand blasting body parts ?? - 07/04/10 04:17 AM
Quote:
When a car sits in the sun, it all gets hot more or less evenly and slowly. When you balst, I can easily believe the abrupt rate of heating and the fact that it is localized plays a role - if not all of the cause. Of course, the pressure can't help either.
Trust me, it ain't the heat. If I take a flat piece of sheet metal with out any bends in it and lay it on the floor and stand back 3 feet and blast it with sand or alum ox or black beauty, it will bow up towards me and there will be no heat to the metal. If I turn it over and blast the other side it will lay flat again, but will now be slightly larger than it was originally. It's peening or stretching the surface. Plastic media won't do this because it is softer than the metal and won't change the surface profile. Don't get me wrong. I can create heat and destroy a piece of metal if I try. I would NEVER let anyone use sand on the flat part of sheet metal unless you just don't care about your results. You may not even notice the warpage until you go to block it out. Very hard, if not impossible to correct.
The biggest problem with doing your own blasting is not having enough air. I'm talking about CFMs(cubic feet per minute), not PSI. That is why we use a rotary screw compressor that puts out 200+CFM of continuous air.
A 7/16" nozzle @ 80 PSI requires about 180CFM to run continuously. That's alot of air. Even a really good piston compressor may be able to sustain 30 CFMs, not enough without constantly waiting for it to catch up. I can't tell you how many times people have brought me stuff that they have tried to blast and either given up or burned up their compressors. It takes them so long, it starts flash rusting before they can finish a piece.
I'm all for doing everything I can myself, which is why I started my business, but sometimes it is all about having the right equipment for the job at hand.
People tend to think blasting should be inexpensive and easy until they try it themselves. It is a nasty, miserable, dangerous job without the right equipment. I'm talking about full respirated blast helments, big compressors, proper hoses and nozzles, lighting, expensive media, recovery equipment,etc. Most home sand blast units use 1/8-1/4" nozzles that shoot a pattern of about 1/2" in diameter, which is fine for small parts, but will take forever to do larger areas and will barely break the surface of many coatings. Our units shoot about 2-3" diameter and flow enough media (about 600lbs/hr)to remove almost anything. Plastic media only requires 30-35psi vs. sand which takes 60-100psi to move because it is heavier.
But, if you have the patience and the time, go for it.
Posted By: DaytonaTurbo
Re: Sand blasting body parts ?? - 07/04/10 04:27 AM
Quote:
People tend to think blasting should be inexpensive and easy until they try it themselves. It is a nasty, miserable, dangerous job without the right equipment. I'm talking about full respirated blast helments, big compressors, proper hoses and nozzles, lighting, expensive media, recovery equipment,etc. Most home sand blast units use 1/8-1/4" nozzles that shoot a pattern of about 1/2" in diameter, which is fine for small parts, but will take forever to do larger areas and will barely break the surface of many coatings. Our units shoot about 2-3" diameter and flow enough media (about 600lbs/hr)to remove almost anything. Plastic media only requires 30-35psi vs. sand which takes 60-100psi to move because it is heavier.
But, if you have the patience and the time, go for it.
Thanks for chiming in, that was the point I was trying to make. To sustain the necessary air pressure with a shop compressor you have to use a 1/8-1/4" tip on your wand sandblaster and it takes forever and a day to get a large area done. Go try it and see for yourself. It's like sanding down an inner fender with something the size of a pencil eraser.
Posted By: Boise Chall
Re: Sand blasting body parts ?? - 07/04/10 04:42 AM
I'm in Idaho Things don't rust here. I have an old junk valance that I tested out my sand blaster on when I first got it 6 or 8 weeks ago. I blasted half of the valance and left it outside uncovered. It has rained 3 or 4 times since then and it's not even starting to change color yet so I don't think it will rust before I get done. I understand what you're saying about having a pro do it. I did have a pro do the important parts. But under the battery tray will never be seen and the area under the trunk behind the bumper well if anybody ever sees that I don't think they will live to tell the story because the tires would have got him first.
Posted By: rxod
Re: Sand blasting body parts ?? - 07/04/10 05:28 AM
I'm in Florida, so the humidity gets to metal fast.
Posted By: 4BBodies
Re: Sand blasting body parts ?? - 07/05/10 04:57 PM
Also, 80 grit on a DA works well on surface rust. Time consuming, but it doesn't heat up enough to wharp anything. Bad pitting would have to be spot blasted, then etched and filled. I use short hair fiberglass, as it is permanent, but goes on like plastic. If you etch it afterwords, it will hold up fine under epoxy primer. I did a hood this way 3 years ago, it still looks like I just did it. Maine sucks humidity wise, it is like Florida, only COLD all the time. But as long as you get rid of the rust it won't come back to haunt you.
Posted By: Stanton
Re: Sand blasting body parts ?? - 07/05/10 07:29 PM
Quote:
Why does it matter if the panels have a little warping in them?
Now this is a REALLY stupid question or statement! The simplest answer is LESS WORK to fix them!!