YOUNG FOLKS BUDGET

Auckland Star, Volume LXI, Issue 217, 13 September 1930, Page 2 (Supplement)

YOUNG FOLKS BUDGET

Well boys, liow have you been progressing with the model described in last

■week's issue? I hopo that those that'll ave made it will have found that it is a dandy, little flyer. Some further details have been asked for in respect to this model. Most of the trouble seems to Ijo in. connection with the covering of tlio wing and tail surfaces. A good tip is to wet the silk before it. is'put on. The exact way that I cover a wing is as followst I take the wing skeleton, which consists of the long spars connected by the bamboo ribs. Usually there is a semicircular wing tip glued and bound on each end. Now smear the glue (any cold glue- will do) along the spars, on the centre wing rib and round the ends, but not on the other wing ribs. Get the glue evenly covered along the top surface only, as it is not necess~ary down the edges. Now wet the silk thorouglily, then roll in a dry towel to take out the surplus water. Now stretch it out, and, having someone to hold the whig carefully, lay it on. Pull the silk gently, and get all the wrinkles out of it, pressing it down on to the glued surfaces. You will have a margin, which is to be cut off later, of about one or two inches to spare all round. Now place the covered wing on a flat board with a book under each end. This will allow it to dry and not disturb the dihedral angle which you have previously bent into tho spars. On a warm day the. wing should dry in about 4 or 5 hours. As the silk dries it tightens up, and the surface should be fairly smooth and taut, The surplus silk is now cut away with an old safety razor blade and trimmed up neatly. Now for tho dope. If you cannot get all the materials mentioned in theso articles, write in and the information will be forwarded you. With a smooth brush, apply the dope quickly, covering tho upper surface only._ As tho dope dries fairly rapidly it is a

MODEL AEROPLANE SECTION, HINTS ON CONSTRUCTION.

good idea to hold the wing as it dries, and by twisting it it is possible, to stop warping, which troubles so iiiany model Aeroplane builders. The surface should now bo like a drum, so that it will "ping" if tapped with the fingers. The tail ana rudder surfaces should be treated the same way. For-a good model it is essential to have the wing and tail true, and smooth. Now, about the light-weight model competition, I can say that the class of work was very fine, and the judges had a considerable amount of difficulty in the weeding out process. The main trouble seemed to be getting the wing nice and true. It is certainly very difficult with a paper-covered wing. However, a shade heavier wing spar would have in most cases overcome this.

Before the fine weather settles in it would be, a good plan to make several models so that you can enjoy ,the first calm weather that conies along. The week-ends lately have been very wet and windy, but cheer up, you Will feel all the better when good weather arrives. There has been a question asked quite- a lot lately: "Should one launch a model into tho wind or down wind?" Well, it depends on circumstances. In a very light breeze, say three or four miles an 'hour, certainly always launch your model down wind. When the breeze is a bit stifl" I usually set my machine oft , into the wind, the idea being to get height quickly, for the model will nearly always turn round and fly away down wind afterwards.

In launching your model do not throw hard, just a gentle push being required. If the model goes up and stalls bring the wing- back a bit. This adjustment should be tried and altered until the machine will rise easily and fly steadily. Well, boys, the best of hick with your work. Write in if you come up against any difficulties and'l will endeavour to set you right.