Use a #11 blade in a #1 size metal handle.īuying new blades in hobby or craft stores can cost from $.50 to $1.00 each. The hobby knife with a #11 blade is the “standard” for hobbyists. Then, change to 320 and finish out with 400 grit. For example, if you are shaping an airfoil into 1/4″ balsa stock you’ll want to start the rough form with 220. Anytime basswood or plywood is used you will need to “step-up” to a rougher grade paper, 220 or 320 grit. This article is primarily about balsa nose cone and finned rockets. It will shape fins, dress up body tube ends, smooth a nose cone, and easily sand balsa fillers. When using sanding sealer or Carpenter’s Wood Filler (CWF), anything rougher than 400 grit can sand through the treated surface down into the rough wood.Ĥ00 grit is the great all-around paper for most rocket construction. This is the extra fine, “Wet /Dry” paper. In LPR model rocket building I go through a lot of 400 grit sandpaper. sells 400 grit in self adhesive rolls, catalog #AR33040 Great Planes sells self adhesive sandpaper rolls, the finest grit available from them is 220 grit.
This is the most comfortable and stable sanding block available. My new favorite tool is the aluminum Easy Touch Hand Sander from Great Planes. Both sides come in handy for contour sanding. In addition to being a comfortable sanding block, the lower half of the block has a both rounded and wedge shaped sides. Don’t over tighten the wing nut – over time it could strip the bolt. Center the upper half of the block, set over the inset bolt and tighten down the wing nut. Unscrew the wing nut and hold the sand paper around the larger wedge of the block. TIP: Cutting sandpaper with scissors will also sharpen them! Only fine grit sandpaper, 320 grit or finer should be cut with scissors. Cut into four equal rectangular pieces using scissors. Fold a full-size, new sandpaper sheet into quarters. The Warner block conveniently holds a 1/4 sheet of sandpaper. The Warner block is the best wooden block I’ve found and is cheaper and more durable than the X-Acto brand block. I have owned many blocks over the years from homemade, X-Acto brand and various hard rubber styles. It’s available online as the Warner #436. I suggest the Warner Drywall sanding block. You can’t possibly sand the flat sides of fins (and keep them flat) using sandpaper over your fingers. Rockets must be safe to fly and the Range Officer will check all rockets before they fly to make sure they won't tumble in flight and bit's don't fall off.A Sanding Block is a necessity for fin shaping, body tube ends, and nose cone shoulders. Whatever you stick on to the rocket must be glued on firmly to prevent bits flying off at launch.
We must also take steps to make sure no bystanders get hit by flying parts. Safety is very important for this challenge and you enter at your own risk.
It should be capable of being angled to 30 degrees of vertical - which is the angle we will be launching at to reduce the risk of rockets coming straight down and landing on someone's head. It must also have a pressure gauge so everyone can see that the launch pressure is 20psi, and there must be some way of letting the air out in case of emergency. If you do make your own launcher it must be able to launch with the operator standing about five metres away - so a long string would do. A launcher similar to the one pictured will be provided on the day of the challenge, but you are welcome to make your own if you like.
0 kommentar(er)
