EJWash1

My Feedback: (3)

GREAT vid! Looks like you guys had a fun time. I've never been to a model biplane fun-fly. It was nice to see a representation from sport-bipes to classics.

Thanks!

Jaybird

Yes, the outer rib tabs of both wings are about 1/8" to 3/16" off the building board with the center section flat. I'll see how things look with when the bottom sheeting is added. I have two incidence meters so I check both wing halves at the same time. The only draw back is they are heavy and can influence what the panel does until it's supported by the struts. I'll keep going and make adjustments where I can.

I have a Concept Models 1/6 scale Fleet MS biplane that I bought at a swap meet many years ago all built (and very well done at that). The kit was designed for electric, but back in the days of big can motors and giant NiCad packs so it is VERY lightly built. The wings weigh very little and are extremly flexible, especially with the Coverite iron-on fabric covering. You can hold one wing tip and easily twist it 15-20 degrees at the other end...the Wright brothers would have loved it! I found I had to modify the "N" strut assembly and secure it at all four contact points instead of the two that the plans called for. I also added functioning clip-on flying wires so I can take it apart for travel. Now it is a very rigid structure and the plane flies great.

Jaybird

EJWash1

My Feedback: (3)

Not sure if your Citabria flying was in a metal wing or not. The 7ECA I started in had a wooden wing (ribs and spar). On my first walk-around, my instructor grabbed a wing tip and shook the wing - hard! I was pretty impressed with the way it flexed and rumbled. Wood - crazy stuff!

Jaybird

I added the bottom leading edge sheeting last night and the wing came right back to shape...sorry for the panic. Now on to the wing tips and the center section sheeting. The trailing edge of the center section seems quite thin compared to the triangular trailing edge stock that gets added to it. The instructions say to center it on the existing trailing edge but there will be over 1/16" of material sticking up above and below the center section sheeting. I guess it just gets sanded down flush but there isn't clear instructions. Did anyone else have an issue with this area?

I can see the finish line from here!

Jaybird

Zor

Opening the above posting, a TROJAN HORSE was blocked by my anti-virus.

Zor

Jaybird

Not sure what that means for you, but it's just a regular post as far as i know.

Jaybird

SitNFly

My Feedback: (54)

These beautiful planes are making me jealous and giving me feelings of inadequacy.......

Zor

Jaybird,

Just clicking "quote" to reply to you again brought up the popup window saying "a trojan horse was blocked".

I think the trojan horse is infecting RCUniverse and not originating from your computer.

I also saw the warning while connecting to RCUnverse before trying to reply to you.

Zor

EJWash1

My Feedback: (3)

Told ya! (oops, did I say that out loud?)

It is discorncerting, glad it worked-out.

Jaybird

I decided to use the kit interplane strut die-cut parts as a starting point and mounted the "L" brackets to the underside of the top wing. I have installed basswod blocks under the spar to screw into and 1/16" basswood strips for them to sit on rather than the soft balsa. I transfered the location of the spar relative to the struts from the plans and then drilled the front mounting hole. I'll add a basswood block an inch or so away from the spar along the side of the strut mounting rib for a second "L" bracket and screw. I did a rough assembly of the wings and braces and everything positions itself pretty close to the marks. It was an evening of measuring diagonals and checking incidences so not a lot of building got done, but I'm more comfortable that the parts will be aligned properly when it's finished. The "L" brackets are Du-Bro metal landing gear straps bend over in a drill press vice.

Jaybird

Sandmann_AU

That's a great idea and should work well, I wish I'd thought of it before I assembled my wings. I notice you're only using the plywood inner parts of the interplane struts, without the balsa outers... what are you going to do with the struts? Make new ones from thicker ply? Use the standard inner ply & outer sheeting, just without the wire fittings? The standard design of the struts will be thicker than the ply inner you're using as a template, will your finished struts be as thick as the standard ones? And if so will you be embedding the brackets into the strut somehow so they sit at the standard location, or have the brackets against the outer face of the strut and just move them inboard a little from standard?

Hmm now how am I going to re-engineer that onto my plane without completely disassembling the wings?

Zor

i liked the idea of not having to use a screw driver and pliers to assemble or disassemble the wing..

It also provided attachment points for the active flying wires.

Zor

Jaybird

Hi Matt. I will make a "sandwich" using the inner struts similar to the plans. One side will have 2-56 blind nuts and the other side will ride against the bracket. I had thought about making pockets for the brackets inside the struts, but decided it would make assemlbly easier if they could just slide into place with both wings on. I may change my mind later, but I wanted to test my idea before I went much further.

Jaybird

Sandmann_AU

Fair enough, that's what I would have done too. Maybe you can find some small thumbscrews to use in them? You'll probably also want to harden the balsa where it presses against the brackets so it doesn't squish, either by soaking with thin CA or putting a small thin ply plate there.

My only concern (a very minor one) is that the original I struts are fixed at 4 points, front & back of the top & bottom, whereas yours are only at 2 central points. If the struts are hard against the wings that'll probably be ok, but if there's any play it'll let the struts rock fore & aft, allowing the top wing to wiggle around. I guess that's why GP arranged their ARF struts so the bolts pulled the struts down/up so they stay hard against the wings. With your 90 degree brackets you might want to use 4 per strut, emulating the original mounting points. Other than that I can't see why it wouldn't be a really good idea.

I think if I were doing it from scratch I would have left the landing gear straps straight and mounted them to the side of the ribs, rather than bending & mounting to the top. Hmm no reason I can't do that now really, it just means cutting out 4 panels of covering from the wings, adding the brackets, then recovering. Something to think about.

Jaybird

I'll be adding a second block and bracket about an inch or so back from the spar on the side of the rib and there will be two screw points at each wing. I was testing things last night and ran out of time before I could add the blocks. I plan to wait until the wings are completly fit up before drilling the other holes so that I don't unintentionally add any twist or misalignment. I was thinking I'd sheet the struts in thin plywood and that would give a hard bearing surface and material for the blind nuts to work with.

I thought about mounting them straight along the sides too, but then covering becomes an issue and you can't adjust them or replace them without cutting the covering again. You also have ot add some sort of support for the covering or it may tear later on. My plan is to make it so I can remove the brackets for covering and then screw them back in place into the mounting blocks underneath the covering. Not as pretty, but a lot easier to do maintenance later on.

Jaybird

Sandmann_AU

All good ideas. You seem to have really thought it through. I'm interested to see how it comes out.

Jaybird

Well, I've been trying to figure something out for the last year when I started building it in Feb 2010. I even thought about the using the new ARF version's struts with the knurled thumb screws, but it was too hard.

Oh, the strip of paper between the top of the strut and wing sheeting/cap strip is there to simulate the thickness of the covering so I didn't have it too tight against the surface.

Jaybird

Jaybird

Another snow storm! I think we got abot 10 inches of new snow with lots of drifting on Friday. I attended a concert last night and got home about 11:30 at night and had to bust through the plow mound at the end of the driveway to get into the garage. I'll be spending most of the morning cleaning up before I can get back to the important stuff in the cellar...darn! It's about 20 degrees out and the wind is westerly 9-10 mph gusting to 17-18...not even decent enough to fly in. There's another storm on the way for Sunday so I guess I'll have to build after church and my chores are done.

Jaybird

EJWash1

My Feedback: (3)

I was with Matt on the struts. More support with two bolts at each end of the strut than one.

Jaybird

Three hours of roof raking, shoveling and snowblowing followed by a late lunch and then nine hours in the cellar...whew! I decided to sheet the lower wing halves before mating them to make sure I knew how they would sit in the wing sadle. I added a thick doubler rib to the bottom half of the last full rib so that I could sheet the underside center section after gluing the dihedral braces. Also added the top rib cap strips and the second mounting block to the top and bottom wings. A lot of sanding and shaping for most of the time. I'm very pleased with how the bottom wing sits in the saddle and the incidence is zero with the datum and is the same at the root and the tips. The top wing tips still have about 1/2 degree of upward twist. I may see if I can take care of it with the wing struts. The center section is minus one degree as it should be and the tips are minus 1-1/2.

Another snow storm in the forcast for Sunday and Monday...We're running out of places to put it!

Jaybird

EJWash1

My Feedback: (3)

I notice that the wing isn't finish sanded, particularlyat the leading edge. I'd measure the incidence once the sanding is complete.

beagleone

Sorry for the interruption! I just picked-up a Skybolt an auction and just want to know if anyone can tell me who's kit or design it is? The top wing is 76" and the fuslage is 64". It weighs 14lbs. bare bones empty. It has been rebuilt. I plane to strip it down and go over it compleatly this fall and next winter and could use some help. (first bi-plane)

smithcreek

My Feedback: (25)

Hostetler designed a 76.5" and Bob Dively designed one, but not sure on the wingspan of that one.

Sandmann_AU

Interesting landing gear on that one... looks a lot stronger than the GP design. Wonder what the weight difference is.

EJWash1

My Feedback: (3)

I have the 1/4-scale Hostetler Plans and a kit by Precision Cut Kits. The Hostetler kit is designed after the Sig 'Bolt kit.