RE: Matney's ZOOMER
Friends:
If I can pass on one thing I have learned in nearly 60 years of buildilng model aircraft it would be the need for a stable, flat, streight and level workbench. You simply can not build something as close as we need on a new or old, hollow core or soild core door, or two stacked etc. or any other similar surface. Give yours a test. Find a good streight edge or spirit level, long enough to nearly reach the length of your table. Now, sit the SE on the table from left to right corner. Take a playing card and see if it will slip under the streight edge. Then go to the opposite and inspect again. Did the card go under the SE at any point? Is the bubble centered on the bench in all directions? If so, your bench is out of whack and so will be anything you build on it. Assuming your bench passes this test, now place 2-4 concrete building blocks in the center. Is there ANY deflection from the weight based on the playing card test? Maby some twist? Anything you build will follow your work surface, especially foram cores and built up wings. Doors used as tables will frequently twist some depending on the moisture in the air on that given day, just like the doors in your house during the winter. I am not opposed to doors used as a table top, just against doors laid on some saw horses or other temporary framework. Steel frames and tops can be a problem from heat distorting the framework during the building process. Sooo, you ask, old poop, what did you do, build yours with a transit. Well, acutually yes for final finish level, but not really necessary. You can build from normal dimensional lumber, 2 X 4, 2 X 6 etc. but finding some streight wood today is nearly impossible. You can take some select material to your local cabinet or door shop and have it streightened.
Its best, and cheapest to start a bench with lumber yard micro-lams or mini-lams. These are man made materials and truly streight when purchased, and will not shrink with time. You should be able to purchase 1-7/8 X 8 X anything from a good lumber yard. If you cant get a 6 or 8" deep lam, get a 12 or 14, and have the yeard cut it in half for you. A 8' bench needs 8" rails to avoid deflection. Make side rails and ends all from the same material, fasten with screws at least 2" into the joining materials. For a 3' wide or 4' wide bench, you need only 3 beams 2" OC. My bench is 3 X 7 and works out well. Find some quality marine 1/2"plywood and cut to size. Do not scrimp here or you will pay dearly in the long run. With your frame square and level, attach the ply top with 1-1/2" screws counter sunk into the ply about 12" O.C. Now, back to your streight edge play. If the ply is not perfect, place a playing card between the frame and top and use the screws to adjust the height until level. Its importent to get everything flat and level so you can measure off the table top or use incidence meeters knowing you are working off a level surface. You need only to keep the plane in place when using incidence meeters as you can adjust for a datum line to get back to 0 or whatever. So now, your almost done with a great new bench. Put one or two buddies in the center of the bench along with your streight edge. Will bet there is no-nada-zip deflection even with 300 pounds or so. That my friends is a work bench. Now, spray the entire bench with a non-water based paint so it does not move during high moisture periods. Oh, yea, gotta bench, what you gonna pin to. Buy 2-3-4 pieces of sheet rock from the lumber yead, cut to bench size. Now you have multiple layers of pin and cut board. Use both sides of each board. I do 4 at a time, and tape the cut edge with duct tape. The 4 will last me for a lot of years. I spackle and sand any minor bad spots created with dumb thumb. If you want a movable table, make the legs from 4 X 4 and add wheels. Wheels make things easy to move around, but gotta level in place before starting a new building project. Oh-yea, the finished product is heavy, so don't plan on running it over to a buds house for a quick project without some large help. What ever you build now is going to be streight and level, even the arf's will become better flyers just cause they are right on. ENJOY