APIA

Have been working on a 4*60 kit. I have read numerous post on this build and have a few ideas and questions. I have read a few post that that airframe is weak aft of the wing TE. Does anyone know where the "weak link" is?
I am in the framing stages, and now is a good time to address this. In anticipation of weakness between F3 and F4 I fabricated a diagonal brace, and plan on sheeting the turtle deck with 1/64 ply.
I also have read that the control rods move around with heat, lots of heat in Texas. The post referenced installing golden rods inside the stock outer sleeve. Will epoxy hold the sleeves together?
Other mods that I am doing include adding a hinge point to the second wingbay inboard, as I have also read that this will be beneficial if removal of one bay is desired. Removing one bay will reduce floating and increase the roll rate. I have also decided to go with an Ohio Model Products tailwheel which will require beefing up the TW mounting plate.
My plan is for a Saito 72 for power.
Appreciate any input
-Tom

CTDave

My Feedback: (1)

The one I built had a 91 on it awesome,also sheeted the turtle deck with balsa sheeting just so the covering did not sag.I kept the wing full size and did not have any trouble landing.I used sullivan control rods and never had a problem.As far as the weak point I did not do anything special but I have heard of some who beefed up the area right behind the TE If in doubt go for it.For the tail wheel I used a light wheel and ran the rod up tru it and bent it so it would go tru a small eye hook I screwed into the bot of the rudder(I sanded the bot of the rudder and put some lite ply along the bot for the hook to bite into worked great)

Rcpilot

My Feedback: (78)

Beef up the landing gear block. It's weak in all the 4* planes.

The weak spot in the fuse is right behind the wing saddle and the cockpit. You can add lite ply and carbon fiber strips to the area.

w8ye

My Feedback: (16)

I used the standard Golden Rods. The outer sheave fits perfectly inside the supplied ones without any retention method. Mine never moved.

For the tail wheel, I just epoxied a piece of 1/4" ply there that tapered to only be 1/4" thick where the Ohio tail wheel fastened on.

The cowl cheeks tend to do a little talking. You will need to fasten a tie bar between them in front of the engine cylinder. I just added another 1/16" ply doubler to mine and they did OK.

The landing gear is too far forward. I fashioned a tapered piece of 1/4" ply to shim the landing gear back at an angle. The plane would wheel land beautifully.

I had a OS 91 Surpass on mine. But a guy at the flying field has a Yello ARF with a 72 in it. It seems to do fine.

Enjoy,

Jim

CTDave

My Feedback: (1)

can you give a little more detail on that landing gear setup,I would like to try that on my next one and also my venture I will be starting this winter (these two planes are very similar) thanx

Lynn1953

How did you modelers sheet the turtle deck and wing? Did you just lay the sheeting over the deck and sand away the lip or did you cut the formers down?

6inchesinverted

do any of you guys sheet the leading edge of the wing?, im trying to build my 4*40 to do 3d, any tips on making it stronger and/or more manuverable?

PropSpinner

My Feedback: (15)

The reason the 4 star and the BTE Venture look alike is because Bruce Tharpe designed both of them. I don't own a Venture but I believe the landing gear is one of the things BTE improved so it shouldn't need modification.

Rcpilot

My Feedback: (78)

I did a 4*40 up for 3D once. Kinda fun.

You don't really need to strengthenn it up too much. Just the usual spots like the LG, tailwheel, and the fueslage needs to be strengthened up behind the wing saddle.

I increased the size of all my control surfaces by 50%. It worked good on the elevators and ailerons--but increasing the rudder by 50% caused adverse yaw coupling. Everytime I gave it left rudder--the plane dipped to the right.

You DO need to increase the size of the rudder if you want to be able to hold it in a hover or torqueroll. How much? I couldn't tell ya. I think the problem with my rudder was that I made it too big on the top. I am not an airplane designer--and I don't really understand WHY my plane acted the way it did. But, I think that if you add maybe 3/4" to the top and then taper it down to the bottom so that you adding 1.5" or 2" to the bottom--you would probably be okay. I think I added 1.5" to the top and tapered it down to 3" at the bottom. Obviously--that was too much.

You might think about adding counterbalances to the elevators. It looks cool and helps to increase the size of them. If your going to replace them anyway--you might as well put counterbalances on them.

I'm uploading a pic of the elevators on my 4*120. They are open framework. I just framed them up with sticks and covered them. Time consuming--but cool. It took a lot more sticks than I thought it would.

I also put a counterbalance on my rudder. Pics included.

PropSpinner

My Feedback: (15)

Have any of you ever shortened the wing? I have a 4*60 all framed up and I though I might enlarge and round the tail surfaces and remove a rib from each wings end then add rounded wing tips. You know sort of like a Super sportster.

nchrome

Well guys I have a 4*60 and have resheeted the sides of the fuse. The reason for this is cause the ply has gotten a little oil soaked and it was due for a face lift. I took and got rid of most of the oil by using a combo of heat and K2R stain remover. Theis helped for the glue to find something to hold to. I only sheeted with 1/16 basa. Then I covered with brite yellow and neon green on the bottom of the fuse and neon green and pink on the wing. Now this is only put on the sheeting on the wings.Then I started adding lights to the bays. About thirty lights total in the wing and trailing edge of the ailerons. I also used those string lights that are for your cars on the fuse. Plan on flying NewYears Eve(fly out the old year and land in the new) I have a Mag 91 fourstroker on the business end of her and am in the prossess of building a set of skies about four inches wide and about 14 inches long. These will be made out of foam and glass over them. Then I will make a mounting cup for the wheel to set in and then fabracate a strap system to hold it to the wheel with about a 20 degree angel up thrust on the skie. Let you alll know how it goes New Years day cause we also have a frozen finger fly in on New Years day. We will also have spot lights on hand incase if the lights go out in the wings. Me and a friend do this every year and what a hooooooooottttttttt[8D]. Better than going out and seeing just how many hampered driver there are out on the roads. You all be safe and have a Marry Christmas and a Happy New Year.