How-To sandblast a trailer

Crystal has some serious focusBecause we bought our trailer used and it was formerly a 1981 (camping) travel trailer it had some signs of wear and tear; namely rust. Structurally it is as sound as the day it rolled off the assembly line. But because it spent some time on the east coast the salinity of the air made it prematurely age and the paint/primer at some point gave way to rust spots and “age spots.” Luckily we own both an air compressor and a sandblaster – the very tools needed to prepare the trailer for primer.

Sandblasting is a general term used to describe the act of propelling very fine bits of material (play sand in this case) at high-velocity to clean a surface. A sandblasting setup usually consists of three different parts: the abrasive itself, an air compressor (seen below), and a blaster nozzle. By launching small bits of abrasive at the surface at a high speed, all imperfections are knocked loose and can then be easily washed off, creating an incredibly smooth surface upon which to lay the new layer of paint. Before we can do that though (which will come much later, I imagine) we need to prime. Why? Primer spray (in this case we used Krylon grey primer) stops rust and prevents corrosion.

Air Compressor
So last week Crystal started sandblasting the tongue of the trailer. We were a bit naive and I say this only to prepare others for sandblasting. It is a long, tedious process and if you don’t have the right tools (which I am not entirely convinced we are not in this category) it can be somewhat painstaking. The key ingredient to sandblasting is, of course, the sand. But running a very, very, close second is the compressed air. Now, our air compressor which is decades old and is only a 30 Gallon, 120/240 Volt, 5.3 CFM model, could only hold enough compression for about 5-6 minutes of intense sandblasting. Then we had to wait 2-3 minutes for the air to build back up. At that point we could then go back to blasting. Now, as one might hope, the blasting is not a large scale process. In fact, because the nozzle is only 1/8 inch in diameter you can only blast about 1/4 of an inch at a time. So in 5 minutes you could cover about a 8 square inch area, if lucky. Considering our trailer is roughly 34,560 sq. inches it is not easy to understand why after about 17 collective hours of sandblasting we only managed to do about 1/3 of the trailer, including the tongue area.

I have to admit that it was a bit discouraging. But when we stopped to think of the purchase price of the trailer, the extra sq. ft. it offered us, and the time we had to do the job (remember, we aren’t moving in tomorrow), it didn’t seem quite so bad. By about 5pm we had primed the sandblasted part and were enjoying a cold one on the back porch.

Please don’t let me discourage you. Sandblasting is a highly effective method of cleaning. The process can be used effectively on steel, iron, copper, brass, aluminum and glass. It can be used to clean up fabricated parts, structural steel, castings, pipes (inside and out) pipe fittings, auto body parts and machine parts. It is fairly affordable and with a little dedication and elbow grease can, in fact, be a manageable DIY project!

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Bigger does not always mean better. Progress does not always mean forgetting our roots in order to forge a new future. Blogger, photojournalist, and hobby farmer Andrew Odom has spent much of the last few years rediscovering the lost art of living, growing, and being truly happy. Visit him online, find him on Facebook, or follow him on Twitter.

9 thoughts on “How-To sandblast a trailer”

  1. I’ve been using a wire wheel on mine. Seems to go fairly fast. For those hard to reach places I’ve got some 80 grit sandpaper and a block.

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  2. @Brian – I do use a wire wheel at times. Especially those hard to reach places. The trailer was a bit older and had not especially been cared for so quite often I just had to straight grind. Not fun!

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  3. Really, no mention of safety requirements?!

    “Silicosis” is a *fatal* and irreversible lung disease caused by inhaling silica dust. Wear a well-fitted, positive-pressure respirator rated for sand blasting applications. Blast well away from onlookers. It may be cheap, but it’s best to avoid sand as a blasting media…

    http://www.cdc.gov/niosh/92-102.html

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  4. True you are Makofan. However, even acute silicosis is based on a test period of several weeks’ exposure to such silica conditions. Most sandblasters in this sort of application are exposed a matter of hours.

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  5. Hi, I own an old Shasta Daisy that I am hoping to restore. I would love to see before and after pics if you’ve got them. Thanks!

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  6. Hey there Irene. I have no idea what kind of RV the trailer was before I purchased it and right now it has framed walls for a tiny house so there is not much to see in regards to before and after. I do apologize.

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  7. Selection of a media other than play sand may speed up the process. Play sand or soft sand does not have the rough edged abrasiveness that construction or coarse sand would have.

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  8. There is a black tar-like gooey substance that is used on gasoline tanks that are buried at your service stations. It lasts for years down there. We used this on restoring Model A’s back in the 50’s but I’m sure there something better today.

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  9. Thank you for pointing out that sandblasting is a great way to get your trailer cleaned. This seems like a great method when you have the right sand. Hopefully, anyone wanting to do some sandblasting looks into finding the best sand possible.

    Reply

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