MODEL AEROPLANE NOTES and Geneal Hobbicrafts

Auckland Star, Volume LXVII, Issue 289, 5 December 1936, Page 3 (Supplement)

MODEL AEROPLANE NOTES and Geneal Hobbicrafts

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THE 1937 PEANUT. POPULAR MODEL WITH IMPROVED DESIGN AND FLYING QUALITIES.

You will remember that I mentioned some time ago that I had. been experimenting with the old Peanut in an endeavour to eliminate the faults in it and bring the design right up to date. So near right has this popular model been that 110 drastic changes were necessary, but the alterations made are undoubtedly for the better. For instance you will see at once that the wing is covered on l>otli sides. This adds climbing power, assists the soaring qualities, and is not really much more work because it lias already had to be covered on the top side, which is the more difficult of the two, and the improved wing section a true Clark Y, allows a flat undersurface, and this gives no trouble at all in covering. The tail gear is kept simple as before, but tlie design is altered, making for simplicity and giving a better performance. The wing is much stronger. Look at that l-Bin by 3-10 in leading edge, and the hefty trailing edge. Combined with the greater depth of rib and the top spar,

tian shown, cemented and bound, and bent back underneath to form the tailskid. The tail gear, or empennage, is very simple. The horizontal elevator is made from balsa sheet Sin by 3in by l-32in. Polish it with very line glasspaper and get the shape properly. I found it best to make a paper template full size, bend it over in the middle, to get your true fore and aft central line, and then cut the balsa accurately to size. Now cement the last inch of the main spar, the portion that is bevelled off right along the centre line, pinning it till dry, then removing the pins. Now pin and cement the strengthening piece (l-Bin by 1-lGin on edge) on the starboard side. [When this is dry fit the rudder on the port side, and then fit the other strengthening piece outside of this again. See that the bottom of this is stuck to the elevator and its side to the rudder. See that the elevator is truly horizontal and that the rudder is properly upright. Now for the "wing. With a razor blade and glasspaper round off the leading edge (l-Bin by 3-10 in on edge) to con-

this wing will stand a gale. I have flown it repeatedly in one. The Din propeller is correct for the new design. Thir; model flies consistently for one to. two minutes on this propeller. I tried out larger and smaller ones, and the result was not so good. If you want, and who does not, a model that will come out and fly every time, in almost every weather, here is 'the model for you. Another thing, the time to make it up has been shortened by every means possible. I made the last model up, the photo of which' is shown, in exactly two hours, and I did not have marked out ribs to work from. Incidentally, the last time the actual model in the photograph was seen, it was heading away over the Three Kings, and was lost sight of in the distant sky. Xo reward is offered for its recovery. Now to work. If you Ret a kitset of this Peanut you will find in it all the parts necessary, and in a convenient form to make it up quickly. The plan accompanying it is full size in all essential details, and the wing can be built right on the plan. Otherwise proceed as follows: Draw out the wing full size 011 a board, also the tail surfaces.' There is no need to make the full size drawing of the main spar. Start work on the fuselage. This is a piece of tough balsa lo 3-Bin by Jin by 3-10 in. Sand it smooth for appearance sake, then cut awayithe bevel at the rear. Now fit the propeller bracket, which can be aluminium or thin steel. Bend the undercarriage wire (all wire is 20 s.w.g.) nnd note how the central portion runs along the fuselage spar, being firmly bound with cotton and cemented. Allow it to run along l at least Jin. Bend the undercarriage legs out so that the wheels have a track of Gin. Slip on lin wheels (wood or aluminium) and bend up the outside piece of wire axle to keep them in position. Now make the rear rubber hook and combined tailskid. This is pushed right through the main spar in the posi-

form with the rib design. Then taper or bevel away the trailing edge, but do not take off too niuoii. Then cut out all your ribs. Each half is then made up separately, and the balsa tip piece fitted. Leave out the middle rib in the meantime. When both sides are made butt the spars together at the centre, raising the wing tips Sin, and go to a little trouble to get the angles at the centre a nice fit. Then cement the ends of the spars and fit together, at the same time fitting the centre rib in place. All to set. Whilst setting make up the wing clips to the shape shown. Note that the rear clip is deeper and has longer •arms. The arms on the front clip are turned back and pushed into the leading edge (after covering the wing), the paper being scraped away so that the

wire gets a firm cemented attachment to the -wing spar. The wire- runs along the front of the wing spar. The rear clip is cemented along the trailing edge and is not pushed in at all. Neither clip is bound. I have had twenty or thirty flights with a model using this method without the Clips being loosened } at all. To go back a little. Just a tip or two on the wing covering. Use ordinary office paste sparingly or strong dope or banana oil as an adhesive. Cover the bottom side first.- Just run adhesive along the bottom edges of the spars and over the full surface of the balsa wing tip. Pull the paper out tightly and apply one half (or side) at a time. When dry, cover the top side. You will be sure to get a Tew wrinkles, but get as few as possible. Allow to dry. Now spray the whole wing with a water mist, using an ordinary fly •spray. As soon as sprayed and the paper dampened evenly all over both sides, hold the whole wing above an oven or well up above a gas jet. The warm air rising will let the wing dry out in approximately five minutes. Hold the wing in the two hands and as it dries give it a twist, so that the leftband (or port) leading edge is slightly higher than the trailing edge on the same side. Give it a little too much, so that as it dries it will have a permanent set (or wash-in) of 1 -Sin. This counteracts the torque of the propeller. Make the propeller from a 9in redicut and fit the spindle. Slip on two collets, loop on six strands of l-Bin by l-30in rubber, the skein being 18in long. Lubricate the rubber well with correct model aeroplane rubber lubricant, and if you wind by hand give the propeller 100 winds and launch it, with the breeze under the port wing. You will be amazed at the climb. You remember the adjustments, don't you. If the model does not climb set the wing forward on the main spar. If it goes up too steeply and stalls, move the wing back a little. Now, with a four to one winder, you can get up to 180 winder turns, or approximately 750 actual turns on the

rubber, but don't rush it. Work the turns up slowly on each successive flight. The sqjiring qualities of this model are such that, assisted by the slightest ascending "thermals" it will go out of sight easily. It will climb to over 100 ft quickly and easily, and its rubber duration without .thermals is 60 or 70 seconds, which with tlie glide assures a minute and a half easily. It is consistent and strong. If you wish to dope the wing (against wet weather) use ordinary model aeroplane dope of the weak consistency. Those who wish to get the kitset of this model can do so by sending a postal note for 2/0 to "Propeller," care of the "Auckland Star," and a full kit will be posted to you immediately.