Two Cylinder Magazine

Sandblasting
The Rusty Acres Approach
by Dan Peterman

Most everyone would like to be able to sandblast tractors while they are all in one piece; it would cut the preparation time for painting considerably. However, this is another of those things where something that sounds great gets shot down by ugly facts… This method simply doesn’t work for a number of reasons. Why, you ask? Well, for starters, what many people fail to realize is that no matter how well the various crevices have been sealed up, when you sandblast a tractor, sand gets everywhere; in the seals, bearings, fuel tank, inside the crankcase, main case, and rear axle housing. Not to mention that the precious serial number plate is sometimes barely readable, no matter how many times you told the sandblaster not to hit that area of the tractor. Stories abound of beautifully painted tractors coming out of a museum or up for auction that are full of sand.

As you might expect, I’m not in favor of sandblasting an assembled tractor. Here’s one reason why: Years ago, a neighbor down the road from us was going to have an auction of his collection of about 40 or 50 Model “A” and “B” Tractors. My dad and I went over to see how the preparations for the sale were coming along. As we drove up, we could see that he had a little assembly line going; one son was power-washing, the next son was sandblasting, and the owner was spraying green and yellow paint. We took a look at the finished projects… If they were moved, sand could be heard tinkling in the brake drums, and be seen running out of the belt pulleys. We left without a word. Come sale day, it was obvious to the buyers what had been done; in retrospect, the man would have been much better off to have left the tractors alone, because the buyers had to tear them completely apart to clean the sand out of every place you can imagine, and some places that most people could not imagine.

I have ended up re-restoring a number of tractors purchased at auction by customers. I shudder when I take out a drain plug and watch the sand/water/oil mix come streaming out, or when turning the fuel on and watching the sediment bowl fill half full of sand. Just trying to read the serial number plate so that I can round up the correct parts can be quite an exercise.

Now, don’t get me wrong; I’ve sandblasted a complete tractor before, but only those that were going to be taken down to the main case and be completely rebuilt, with every nut, bolt, and seal either cleaned or replaced.

Sandblasting sheet metal is an art, and should only be attempted by those who have some experience. Personally, I never sandblast sheet metal until it has been removed from the tractor; nor the rims, wheels, and other pieces that have been taken off. I do my own sandblasting because, over the years, I’ve learned how much pressure can be used on sheet metal and other items without warpage or other damage. Too much pressure can and will warp sheet metal and other thin metal items! I learned some of this the hard way because, if sheet metal is warped, getting it back to its original shape can be difficult, to say the least. And, having to “shrink” metal to get it back to its original size is no fun, let me tell you!

That’s not to say that a professional sandblaster won’t do a good job. An experienced professional can do a great job, but caution whomever you hire to be gentle with sheet metal and other thin metal components. Large commercial sandblasters put out a lot of pressure, and more than one tractor hood has been blasted beyond economical repair. I once had some metal done by a pro for another brand of green tractor, and the side panels looked like a crushed pop can when I got them back. In fact, that episode was why I went out and bought my own machine.

That being said, there’s nothing like a sandblaster for cleaning years of crud and multiple coats of paint from a tractor, and it makes the restoration job go much easier. I’ve tried to economize my sandblasting operations by gathering the used sand off the slab, sifting it out, and running it back through; but, no matter how I sifted and strained, the nozzle would still plug up, and recycling sand was costing me more than new sand. So, I quit, and now just let it go on the ground. I have a desert behind my shop from all the sand that I’ve used over the years!

I clean a lot of the smaller pieces inside of a blast cabinet that I have in my shop. Some examples of the parts I do with it are valve covers, fan shrouds, and wheel lugs; that sort of thing. For those parts I use glass beads rather than sand, which leaves a nice “soft” finish. The only disadvantage to glass-beading is that eventually the glass beads turn to dust and have to be replaced. Always protect yourself and others from breathing glass bead dust and fine silica (sand) dust.

There are many different kinds of blasting materials, including sand, black media, plastic media, and even crushed walnut hulls. Undoubtedly there are more, but that’s what I can think of at the moment. About a year ago, a guy came by and demonstrated a portable media blasting machine. He did a couple pieces for me; one that was very rusty and another covered in greasy crud. After going through the machine, the pieces were just like new. The guy claimed that he could do an entire tractor, all in one piece, and not hurt anything on it including the serial number plate, gauges, or any chrome parts. I’ve not yet had this done to a tractor, but I’m thinking about trying it, as those individual parts sure looked good. I’ve talked to several people who restore classic cars and they said it worked great, even when they didn’t take any parts off the cars. It didn’t warp any metal, ruin the chrome, or even play havoc with the glass. So, I’m relatively sure that this process would work just fine on a tractor. Sandblasting is the old standby, but remember to make sure you think ahead about the horrible things that could happen before you hire a sandblaster or attempt to do it yourself.