|
Refinishing Leslies (and working too hard) |
||
|
You can see here what a pleasant job sandblasting can be. We started this project last July, when the temperature and humidity were so high, that most sane people moved out of Florida. Working with sand requires the right tools: The sand blaster shown in the pics is a very inexpensive, gravity feed model. It holds about 100 pounds of sand, and it's easy to wheel around. A single feed hose connects the sand hopper to the gun, and the compressed air line also attaches to the gun. Blasting requires a lot of air per minute, so you'll need a pretty serious compressor to do this right. We've got a fairly large one - 220v, 60 gallons, 6 h.p., and 10.2 scfm. We also have a 110v portable, 25 gallon, 4 h.p. model, but the extra power of the large one helps a lot for blasting. The blasting gun has interchangeable nozzles. We used the small size which seems to concentrate the sand and gave us better results. Nozzles wear out after awhile, and you'll notice that the sand isn't getting much done. Sometimes, you can rotate the nozzle to gain some extra use, but replacement will be needed soon. Dry air is very important, so a trap for water should be somewhere in the air line. I use two of them, and additionally, I have a gravity trap. This is simply 1/2" PVC pipe which runs about 100 feet around the attic, then outside, and back to the compressor room. At the very lowest point of the PVC "loop" is a drain valve. Blasting is messy, and requires a lot of space - somewhere for the flying sand to go. Fortunately, in Florida, we have sand instead of soil, anyway, so it just blends right in. A nice thing about blasting is the degree of control you can exercise. Moving the gun closer to the surface and changing the angle of spray has a large effect on how the sand affects the coating to be removed. It also helps you to keep sand particles from bouncing right back in your face. As shown in the pics, Bec is wearing the very latest FBA (Florida Blasting Attire), including hood and long sleeves. Expect to be uncomfortably warm under the hood. click picture for fullsize view
The three Leslies shown above took about 2 weeks to blast. This isn't something that can be done for eight hours straight, and the weather often limits working times. Blasting on a wet, humid day can cause the sand to clog in the feed tube, or not feed at all. While we were doing these 3, I went ahead and did the 145, too. Gaskets
- Spacers Here is an example of a gasket for the 15". We use JBL speakers for the Leslie bottom, and these specific speakers have a "roll" surround, or compliance. They're designed to be mounted on the front of a baffle plate. Because of this, they cannot be mounted in a Leslie, because the shelf will contact the compliance, and destroy it. Initially, we solved this problem by gluing an extra gasket set on each speaker, raising the frame slightly. We weren't very happy with that method, so I used a router, and cut out several gaskets, using 1/2" plywood. These work very well, and don't pull apart like the cardboard gaskets do. You might also notice the longer speaker mounting bolts, shown below. They come up through the bottom of the shelf, and are secured into the Tnuts with Hot Stuff glue. This configuration allows us to torque the speaker down to the shelf very tightly, and eliminate rattles. Also shown is the gasket we use for the upper drivers. This simple piece of 1/2" plywood replaces the original cheap cardboard tube.
|
||
