A return to model building and flying. Part 45
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On my never ending search for CL difficult to get hold of bit's and pieces I ended up on the SIG website. For those that don't know, SIG is a long established American company that has crossed my path many times in my aeromodelling life.
I was actually trying to find a source of three blade props less than 10inch on diameter. Very rare beasts indeed. Ripmax (spit!) and Perkins do not list any in their wholesale catalogues and I can't expect Tony at our local model shop to go hunting round for a couple of props just for me. Neither Graupner or Kavan seem to list any either, yet I have seen three blade yellow nylon Kavan, and grey Graupner ones in the past. And just what is this business with a minimum seven inch pitch on three blade props? Looks like, yet again, we have fallen prey to the never ending push for bigger and yet bigger engines for RC models. The reason I am searching, is to create a bit of ground clearance on some of my models, and I have just found that three blades have improved the flying of my ASP.25 powered Buster stunt model to a remarkable degree. it seems to act as brake in the manoeuvres that are prone to winding up in a wind.
But back to SIG. I was surprised to find they will deal directly with individuals, and as I write this, six props are winging their way across the Atlantic. I will probably end up paying more than if I could purchase them in the UK, but as I can't find any here that is not a problem.
The SIG catalogue is well worth a look through if you are interested in CL, or FF for that matter. Whilst not extensive, all the CL accessories you need for flight are there, from fuel tanks, lines, connectors, kits, bellcranks and handles, including the Brodak three line systems.
The web site is here. The goodies can be found in the 'Aircraft Accessories' section.
The Real One
If anyone has followed my exploits, they may remember that I won a couple of Brodak kits on eBay some time ago, it's all here if you want to read it. The long and short of it is I built the the Buster, as previously written about, and I now have need of another Carrier model for next season. I also have a twin engine Tigercat kit which I ordered direct from Brodak in the US., and am tempted to build both, but thought better of it and stuck to my philosophy of build and finish one model at a time. If the howling gale that is blowing outside my window as I type this continues for a long time, I may yet get the chance to build both.
Actually the first problem I came across was nothing to do with the kit. I make my own bellcrank assemblys and know from a hard earned lesson with the Crusader to make sure the whole thing will fit inside a wing beforehand. I had settled on one of the Mick Reeves designs but was having difficulty in finding the materials to bring it to fruition. I was also a little concerned by the depth of the whole thing and a high component count. I also need to make two of these assemblys at the same time time, as I will need one for the Tigercat when I get round to building it.
After a week of struggling to get it al together I found myself looking at another setup by Mick Reeves, taken from a much later Aeromodeller publication than the Controlline Aeromodeller Book I had all the other designs from. It took a bit of puzzling over before the little grey cells jelled together in a flash of understanding. Here was a setup that was exactly the same as the unbalanced two bellcrank setup I was using already on my models, that only needed a small piece of flat metal strip and a piece of piano wire to convert it to a fully balanced one. Bingo! all of my Christmases had come at once. I love simplicity and this was it. For once I am not going to try and explain how it works, all I will say is the screw sticking out is the pivot/mount point.. If you are interested enough, you will work it out..
Ordering direct from the states is a practical proposition, especially from Brodak, who do not seem intent on charging really stupid shipping charges like some people, and would recommend doing so for any of the hard to get kits or components on this side of the pond, as sometimes it can even work out cheaper than trying to buy the same things here. I also found a video of Brodak's industrial unit on YouTube which is interesting, here's the link Brodak Factory
I must admit that I was impressed by the Brodak Buster kit, and was not disappointed by the Bearcat when I opened up the box. Nice full size plan and comprehensive instructions.. Worth having on their own as carrier kits were never exactly common and are even rarer these days; so hats of to Brodak for even bothering to still sell them. There seems to be a very high component count for a profile carrier model, but Hey! I like a challenge.
First Task is to construct the leading edges of which two wing halves are made from two pieces of sheet. to form a hollow section. The pieces are held in place by a four cardboard jigs and tape whilst being glued along the front seam, an ideal application for some thin cyano, as the jigs were somewhat loose.
The only problem I encountered was one of the pieces of shaped sheet had an edge that had been sliced off at an angle along it's length, which meant having to glue a piece of 1.5mm² balsa along the edge and sand to the correct taper and shape. Annoying but not a great problem.
The next bit of head scratching was caused by the instructions and plan not explaining that the reference points that are referred to on the wing jigs, are actually a very thin, small, almost invisible, crease line. in the balsa jigs.
I have marked them with a pencil so that they show up. The large ones are the tip jigs and the small triangular ones are the root jigs. Yes, the wing has dihedral.