Little Toot Part 1 Bought a 1/4 scale Little Toot biplane off a guy a little while ago. He advertised it on the net and so I went to have a look at it. It was built from the Dennis Tapsfield plan featured in Radio Modeller. It has a bit of a history. He had built it in 1977 and it served him well through the years, until he, and I quote, "Got a bit silly!" Only the top wing survived. Later he found a fiberglass fuselage for it and got it rebuilt, but fiberglass being fiberglass, it was quite a bit heavier than the original. He reckoned the extra weight improved it's aerobatic capability, hmmmm. Well he would wouldn't he? He was trying to sell it to me after all! I thought it was a bit too heavy but decided in the end to give it a go. I'd driven sixty miles to see it and the thought of going home empty handed didn't appeal, so I bought it! Once I got it home and had a good look at it I realised that most of the weight was due to a gigantic lump of lead bolted to the firewall! Blasted fiberglass! Too heavy at the tail end. The previous owner had had a Webra .91 powering it plus the lump of lead to balance it for a combined weight of about 2.5 lbs. Now I didn't have a .90 spare at the time, I only had a nice new Thunder Tiger .60 Pro and a Super Tigre G20/23. The .60 was definitely not going to be powerful enough to haul an 11 or 12 lb model with any conviction so I had a look at the G20/23. I didn't think I could get it in the cowling but after a bit of investigation decided it would go in but with about half an inch too much poking out of the front! Well, I could figure ways around that. I put it on the scales and guess what? Yes, it weighed almost exactly 2.5 lbs with the silencer. Just the job! I'd rather have more engine than more lead! D'ya know, sometimes it's turns out to be more work to adapt something than to build it from scratch. This was one of those things. Fitting the G20/23 lead to all sorts of unforeseen problems. Firstly, the fuel tank was no longer anywhere big enough . I had to fit a 24 oz tank (I wanted a 20 oz but couldn't get one) 'cos of the much bigger motor. Then because the tank is a lot longer the servo bearers were in the way and had to be moved. That entailed a fair bit of work as supports for the tank had to be glassed in. The fuselage was also damaged at the undercarriage mounting points. The fiberglass was fractured and crazed and so I glassed a couple of 1/8th ply plates inside the fus' to help prevent flexing and then sheeted up the inside of the fus' sides in light 1/4 balsa to help support them, and also to mount the servo bearers in. The worst problems were in fitting the motor. I had to get it right back against the firewall because it was so much longer than the cowling. I made an 1/8 dural 4 point backplate to mount the engine with. With the motor right back on the firewall I had to find a silencer with no overhang towards the back of the engine. I thought it was going to be impossible to find anything like that until I went on the Just Engines website. They have the dimensions of the BCM and J'tec in cowl silencers right there at your fingertips. In my case it had to be a J'tec because it was the only one with no overhang. It's twice the weight of the BCM but a lot cheaper too. As it turns out that weight would be needed! It's actually for the ST2000/3000 engines and supposedly wouldn't fit my G20/23. I asked for an adapter to space it off the motor a bit too. When it arrived I found it fitted perfectly except for the mounting holes. I had to bore out the engine exhaust mount holes about 1mm to get the bolts to pass through. Apart from that, fine. The cowl had to be cut out for the cylinder head and silencer and to be honest there isn't much left of it now. I also had to glass on a 3/4" thick ring of balsa to make up the difference between the end of the original cowling and the backplate of the spinner. I thought this was going to look really naff but, as it turns out, you hardly notice unless you really look. The fuel proofer (Aerocote) attacked the enamel paint I used on it even though I'd let it dry for three days! It's not too bad and if it manages to fly even half decently I'll sort it out later. Another problem was the lower wing mounting. The previous owner had used steel 6mm wing bolts that were very long. They had to go 'cos of the weight. The reason for their extraordinary length was because the cross spar that contained the captive nuts was mounted down inside the fuselage about two inches. This was to allow the aileron torque rods to pass underneath. I couldn't get any 6mm nylon wing bolts anywhere near long enough and so decided to change the whole layout.  I mounted a servo in each wing panel and threw out the torque rods. This is probably a good idea considering the size of the ailerons and the size of the engine being used. This, in turn, allowed me to mount a wing bolt spar at the surface of the fus' as usual, so I could then use standard 6mm nylon bolts. Problem solved! Just don't ask about removing the old cross spar though! What a job.. Rudder is closed loop and elevator is via a large Sullivan cable. One other thing I foolishly did on the lower wing was to add checks underneath just like the full size. Two days later I'd got it done! Well, the job is almost completed now except for the fiberglass undercarriage fairing and setting the aileron differential to about 2:1. I'll set this up with the servo horns. I could do it on the computer radio, but I like to do it on the aircraft for obvious reasons. I'm still toying with fitting the spats. The only 4" wheels I could get are a bit tight in the spats, they're Dubro items and are lovely; you even have to blow 'em up with a bike pump! Another reason I'm toying with the spats is because the whole thing weighs in at an amazing 12.5 lbs (5.7 Kgs)!! Ye Gods! I think I've wasted my time with the whole project! The wing loading will be something like 25 - 26 ozs per sq ft. Too much for good aerobatics. Mind you, I have lots of power! The G20/23 swings an 18" prop' which looks great. I reckon I'll have to make the interplane struts functional too with all that weight! You think about it, if I pull 6G that'll be 75lbs loaded on the wings, phew! Well, I'll finish it off and get the motor run in and then test fly it. I'll let you know how it goes... G :-) (Click Here for Part 2)