Because 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.
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!