ARF Oriental

Ken finished his Brodak Oriental yesterday. He won't post here 'cause he doesn't want to get razzed, so I will.
Stock ARF Oriental, built just with the parts form the box, Brodak tank, B40 engine with a Big Art chip muffler. It looked noseheavy with the stock muffler and Ken wanted to save weight. 10/5 Zinger prop. The controls were set up according to directions- middle hole in the bellcrank to top hole on the flap. Lower hole on the flap to middle hole on the elevator. With the 4 in. bellcrank this gives pretty slow controls and equal flap/elevator movement of about 30 deg. total. 1 oz. of tip weight. Total weight was 41 oz.

The plane had a visible warp to the right, but he flew it anyway. Nose heavy, slow controls, but safe. The motor went rich after take off and quit early.

Put in a new plug, twisted the flaps, and added 1/4 oz. of tail weight. Flew much better, but the motor went rich at the end of the tank.

Added another 1/4 oz. of tail weight, twisted the flaps some more, and put an 020 restrictor in the uniflow vent. Now it flew pretty good, but the motor went lean towards the second half of the tank.

Added another 1/4 oz(3/4 total) tail weight. Switched to a .04 restrictor in the uniflow vent. The whole thing came together and flew well and ran pretty good.

Day's assessment- build in some adjustable controls so you have more trimming capability. The controls are quite slow. You might be happier using the outer hole on the bellcrank and trimming with a narrower line spacing. Take the time to fuel proof the engine and tank area with epoxy and check and fix the wing straightness before gluing it together.

Welcome to the club. Your Oriental experience is about the same as mine, which is fairly well documented in another thread. Mine has an OS LA 40 that goes lean 10 laps from the end of the tank...basically 5 laps too soon.

I didn't find out about the elevator/flap linkage problem until it was too late. I had to cut holes in my nicely finished plane to fix the problem. I hate having to fix something because I 'FOLLOWED THE INSTRUCTIONS!'

These are just teething problems John is dealing with. He's new to the ARF market so there will be a learning curve. Fortunately he's found excellent assembly workers as the planes are very nice. gv