I saw the older build thread of the Twin-Air and read every post. I love the development of the twin tail. Thanks to all for that modification.

I recieved my Twin-Air .45 from Northeast-Aero Christmas day and I'm about ready to start cunstruction. I thought recording my work in a build thread would be a good way to keep me moving and have a little fun. Can I do a second build thread for this kit?

The build:
Twin-Air .45 twin tail
B&D Air Retracts (I'd like gear doors as well, but we'll se how that goes)
(2x) .46 Evolution engines
Futaba radio equipment/servos

The kit, retracts, and engines have been purchased and are sitting patiently on my build board awaiting me to lovingly craft them into something wonderful.

"Get er done" [sm=sunsmiley.gif]

I would love to see another build thread. I plan on buying the kit later this year and installing the same retracts.

This will be my first retract install so please be detailed in that part of the construction.

What kind of color scheme are you planning on? I am trying to design a color scheme that looks somewhat scale but that really jumps out.

Steve:

Have at it, and welcome.

Bill.

Thanks, all.
Gringo Volador, this is also my first build with retracts and yes I'll be detailing the retract installation pretty well. I've also ordered a door kit from SonicTronic (http://sonictronics.com/store/custom...cat=378&page=1). I'm not sure if they'll work, but for $20 bucks I'm willing to try.

Also, I had posted a "question for the experts" in the Kit Builders forum regarding retract doors. Here's the link:
http://www.rcuniverse.com/forum/Gear...2588890/tm.htm

I don't know if doors will prove practical. The retracts are definately doable. I've got the plans with me at work and I plan to sketch out the details tonight. An ounce of planning is worth a pound of balsa. I'll post when I'm done.

As far as color goes--I haven't yet decided. Usually my color selections come from whatever I have availalble. Right now, I have white (suprise), missile-red, and insignia blue. I put more thought into it come closer to completion, but right now I'm leaning for a civilian look with red and white and some kind of 30s era striping and swooping. I'll let the plane tell me what color scheme it wants to be...

Another Twin-Air Build thread? Why not! There are a bunch of folks interested in the best way to install retracts on this plane so that part of the build in particular would generate lots of interest.

Also the instruction manual has undergone a major update since the earlier build thread. It would be interesting to see what questions you have and what additional improvements you can come up with.

So get building!!!

I've sketched out some details on the mains for the retracts and I have a question. I plan on deleting the original landing gear block that supports the mains on the wing. Instead, I'll cut a channel for the gear and a hole in the sheeting on the inboard side of W4 to accomodate the wheel. The actuator for the main gear will be located right under the necelles and at the same distance on the cord as the original mains.

I noticed the original landing gear block mounts to two ribs that are ply. The landing gear block is obviously a structural member. If I delete the block all together, will that weaken my wing structure to the point were it could have structural failure?

An ice storm here in Georgia and work have delayed me somewhat. IOW--Life gets in the way sometimes.

The pictures don't show well but the red circle is around the 1/4 ply rails I plan to add for the gear actuator. It is in the same spot on the wing were the nacelles will go. The top of the picture is the leading edge and the pictures are of the right wing.

Steve:

Just at a quick glance,I'd move the inner W-3 ply rib to the outboard side of the nacelle, and put a W-2 rib in its place. This would give you the two ply ribs to mount the beams for the retracts, put the smaller ply doublers there also.

The heaviest parts of the plane are the nacelles with engines mounted, the fuselage is relatively light. With the gear mounted directly under/inside the nacelle you don't need the greater strength in the root, just be sure to glass the root joint.

Bill.

There's a point that I missed. Thanks! You're right--the ribs on either side of the retract and nacelle should be ply. Best option is to move the W3 ribs to these locations.

The mains are 5.5 inches tall. The wheelse are 2.5 inches in diameter. There's plenty of room between the first two ribs of the wing for the wheel and the 5.5 inches will put the retract in the right place. The measurements work out...

I'll sketch in the nose tomorrow.

OK--sorry about the long lead time--don't ask. Regardless, I'm back and my TwinAir is screaming to me "BUILD ME"! So, I started today. I started laying up the wing and I have a problem. The instructions say to cut the leading eadge bottom sheeting to 3 3/8 inch wide. I do that and lay it up on the plans and it looks like too much material. In other words, the sheet is too wide. The leading edge sheet is supposed to go half way across the main spar. At 3 3/8 inch wide, it goes across the entire spar. Any suggestions?

You let the excess width stick out the front. When you bring it up and glue it to the ribs you'll see it's needing just a slight trim. But if you don''t have it extend beyond the forward drawn line you'll have it too short. Do align the rear edge with the drawn spar centerline.

Bill.

Thanks! I tell ya' I love RC Universe. Got a question and get an answer!

I cut the servor bay sheeting too short--my fault. But all it all a good start.

For any who are building the TwinAir MEASURE CAREFULLY.

I'll also have to relieve the two spars on either side of the main retracts to allow room for the retract piston. Not much of a problem. I'll post some pictures later tonight.

Steve:

This doesn't sound right. Can you post a picture to illustrate?

Bill.

Sure--here are the pics...

Could be the type of retract I'm using. There is a piston rod that needs to go through the outboard spar and the piston itself is a tad too large requiring some relief on the inboard spar.

Included are pictures of the cutout in the sheeting, then the spar cutouts, then the piston in place with the spars temp installed...

Steve:

OK, you're saying "Spars." From the pictures I think you mean the ply ribs. That's normal, to be expected, and perfectly OK.

Bill.

Yeah--I often suffer from "don't really know the right terms for things even though I think I do". It drives my wife crazy!

The pictures don't have the plywood doublers on the "ribs". Truth be told--I forgot 'em. I'm gonna add them outboard of the ribs surrounding the gear piston.

Lookin' great, and brings back good memories! I ended up buying some extra sheeting and tri-stock when I built my Twin Air, so don't feel bad if you make some cutting errors. You won't be the first! Just be careful before gluing.

I'm a big believer in putting plenty of beef around gear mounts, especially retracts. At Bill's suggestion I am considering B&D retracts for the Deullist that I just picked up, so I will be watching and listening to any thoughts you have regarding them. Especially the nosewheel assembly and steering hookups (hint, hint...)

Walt

I'll keep you posted. The B&D seem to be good sets. Flight time will tell, but so far I'm happy with them. I've gotta go get the stock to make the landing gear rails tomorrow. Any suggestions on what I should use? Ply or hardwood?

For anyone listening, I was missing three sheets of 1/16x3x11 stock from the kit. Nothing a quick trip to the hobby shop wouldn't cure. So far, I'm impressed with the kit. I haven't had any wood warping--but the kit has been kept in its box packed by NE Aero since I received it in December. Tomorrow, the top portions of the wing go on. I'm having some tea at TeaFusions (sensless plug--www.teafusions.com) while I review the directions.

I don't see when the opeing for the aeleron servo is cut. Seems that would be a thing to do while I can still easily get at the sheeting from the inside of the wing. Ah--there it is on page 13. Question answered. Never mind.

Steve:

3/8" square section bass wood makes fine gear rails. Have to be careful putting the screws in, if your pilot holes are too small it can split, so be careful. If you're hesitant about using such small rails you can go to 3/8"x1/2" section.

Bill.

FYI Found a typoo in the directions.

Step 14 on page 6--"Using 15 minute apoxy, glue 3/8" x 1" x 7-3/16" plywood main landing gear base groove dodwn on the shetting using the marks made in step 14 as a guid."

That should be "step 13".

Bill is probably right (he usually is) but after breaking the hardwood rails in my P-51 I went with ply and lots of bracing... and no hint of a problem since. I found replacing broken retract rails is not much fun.

My kit was a little short of some of the lumber too (I think), but then I ended up with a bunch of sticks left over that have come in handy for other projects. It worked out well in the end.

I mentioned earlier I think the dimensions are wrong on the leading edge sheeting. Bill said it'll wrap onto the leading edge with just a bit left to sand off. If I'm looking at this right I'll have more then "a bit". Probably closer to 1/2 inch. Yes--I measured right--I measured 5 times before I cut.

From the directions, page 5 step 4: "Trim (2) 1/16" x 4" x 31-1/4" balsa leading edge sheets to 3-3/8" wide."

Time will tell, but I think a closer measurement would have been 3". Any comments from other builders?

Steve:

I fly off pavement, and I fly twins in a very conservative manner. Walt flies off grass. While the 3/8" rails are fine for me, If you anticipate a hard landing now and then, or fly from grass, the plywood laminate would probably be much better.

Thanks for reminding me, Walt.

Bill.

I fly pretty conservative too, Bill, but sometimes my landings aren't too conservative.

Seriously, weight is not enough of a factor to take any chances with the retract mounts.

1/2" overlap sounds about right- it actually helps to have something to grab when wrapping it over the leading edge. After the glue dries then trim it close to flush, bring out the coarse sanding bar to get it about even, then sand to final shape using a finer sanding bar.