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FlyWheel 01-12-2014 01:54 AM

Build: 1913 Eastbourne semi-scale bash thread
2 Attachment(s)
This build is of the AeroCraft (Hobby Lobby) 1913 Eastbourne Monoplane kit, which I will be modifying ('bashing') in order to make it somewhat more scale like than the stock kit. Here are some of my planned mods:
  • The kit has only the top front hood, made of thin card stock, painted silver. however the actual plane the entire cockpit shell was metal (covered?). I will therefore steam some balsa for the hood instead and use a silver covering on all the fuselage/cockpit planks to reproduce this.

  • The kit has a separate V-stab and rudder, the actual plane had a full flying rudder. If I can at all arrange it so will mine. This will require that I put back the vertical support wires that are also on the actual aircraft but left out in the kit.

  • The actual plane used pull-pull system for all the control surfaces, I am hoping to be able to do the same with mine (the kit elevator uses a push-pull wire). I will not, however, have ailerons. The only way I can think of accomplishing this on such a thin wing would be to also use a pull-pull system, mounting the servo in the fuse. This would very likely work and definitely be 'scale', but it would mean the wings could not be removed for transport. So practicality won out this time; it will stay a 3Ch RET with dihedral wings.

  • The motor will be brushless. I was hoping to use a BL inrunner with a gearbox, both for balance and the side benefit of a more scale like sound. unfortunately from what I have been told, noisy gearboxes are an extinct species.

  • Balancing this plane is going to be tricky (even if I could have found that elusive BL inrunner/noisy gearbox combo), AeroCraft even mentions this in the instructions and recommends that the builder 'spare no expense' when detailing the faux engine in order to help put more weight up front. I intend to do this, and may even use a more scale looking wooden electric prop if the weight added by my detailing is insufficient.

Because both forums helped in my research, I'm going to post this build both here and on RCGroups.

FlyWheel 01-12-2014 02:44 AM

4 Attachment(s)
Here we go again! Got the workbench all set up.

The kit comes with two sheets of plans, one concentrates on the wings, the other mainly the fuse, V-stab and faux engine assembly. The instructions start with the main wings so I'm starting there. I don't use wax paper, having found a 2 mil sheet of clear polyethylene works better: It's easier to see the plans through it, large enough to cover the whole sheet (and even part of the build table), and almost nothing sticks to it. Not TiteBond, not CA, even epoxy has a tough time getting a grip.

Well, whaddayaknow! Hit my first bump in the road, and I haven't even started yet! ::o

Note to self: Just because a kit is laser cut does not mean it was cut with any precision! I'm glad I started here; at least now I am forewarned! The ribs vary in length by as much as .125 inches! (and yes, they're supposed to all be the same length; the wings on this bird have a constant chord :mad: )Fortunately the spar notches are not that far off from each other. Still, I had to do a bit of filing to get them lined up too, not so much that it will cause a problem gluing, but my rear spar isn't going to fit as snugly in all the ribs.

With scrap pieces of balsa holding the bunch in line I sanded the ends even. http://www.wattflyer.com/forums/atta...1&d=1389491856
(the TE has not been sanded even yet in this photo)

This will mean that the wing chord will be a bit thinner, but it shouldn't cause too many problems, The trailing edge is ludicrously simple so I'll just have to line the wing up with the leading edge on the plan and let the TE fall where it will (about 1/8 inch forward). :roll:

I'm used to better quality than this from AeroCraft! I hope the rest of the parts of this bird are cut better.
(Primary wing assembly. The planks in the center are to hold the spar up as the rear notches are not a snug a fit anymore.)

Wildflyer 01-12-2014 02:52 AM

How about a CF or alum torque rod/tube for the ailerons?
You could have it at the hinge line or forward and using a control arm linked to a control horn.

Just a quick idea.

FlyWheel 01-12-2014 03:23 AM

That was my first thought too, but I dismissed it because the battery pack sits right where the servo would have to go; where the pilot seat is. Draw an imaginary line from the aileron joint to the center of the plane.

No biggie. I'm not even sure this wing could even support ailerons, regardless of how they're actuated, they are really very delicate, I'm just starting them and I can already see that!

FlyWheel 01-13-2014 01:07 AM

On Gossamer Wings...
4 Attachment(s)
Man, these things really are fragile, I've made dream catchers with more substance to them! And this is not helped by the fact that the wood in this kit is very soft. I always test out the material before starting the build, to seperate the denser, harder stuff to use for the structural elements, but there wasn't any; it's all soft! :concern:

I saw in another thread where instead of a plain butt joint the modeler cut shallow notches in the side of one piece to add strength to the joint, so i copied the technique with the trailing and leading edges where the ribs join them.


Good thing too because The instructions are not exaggerating when they say this plane's structure is fragile. It is obvious that the covering is going to play a major part in the integrity of this aircraft. Those same instructions also tell me to pin down the trailing edge piece, to which I attach the initial structure (two spars and two ribs) and then glue on the rest of the ribs. I took this to mean the wing was built on the table. Bad idea. I got it to work, but I was making things a lot harder on myself.


So for the second wing, I pinned and glued the trailing edge and let it cure as before, but then un-pinned it and glued the remaining ribs on by carefully sliding them on in hand, using the marks made earlier to position them, double checking their position by setting the wing over the plan. Not only did this made the assembly go a lot easier it also resulted in a better job. Since I'm using TiteBond I can get away with this slow method as I have all the time I need to work. Once assembled I set the wings on the table to cure, resting their 'center' spar ontop of a .500" x .500" length of balsa.


Once cured enough to handle I added the leading edge. This was also notched and I had to pin them at an angle to match the angle of the front of the ribs. At his point I'm at an empass. The instructions state:


If you haven't already done so,trim the trailing edge at an angle to recieve the 1/8" sq. wing tip. Glue the 1/8" sq piece in place. This piece should be pinned to the building board at the trailing edge and aligned to the top of the forward spar.

Here is what I'm not sure of. Doing this will result in the 1/8" sq. wing tip crossing under the center spar. What the instructions do NOT say is how the spar is supposed to be joined to the wing tip. Is the spar supposed to be bent down to meet it, or is the wing tip piece supposed to bow upwards to meet the end of the spar? ????

Abuelo 01-13-2014 02:01 AM

The wingtip follows the curve of the rib. In this case, the rib has an undercamber and the tip is on the bottom of the wing so the tip has to match the rib. To leave the tip flat is to change the airfoil and while not a big deal if equal on both wings, will look bad.

Block the tip up to the rib height and taper the end of the spar to match the thickness of the tip. Should be a snug fit. Titebond the spar(s), LE and filler, and TE to the tip and let it set up before handling. Sand smooth.

I can't quite tell from the photos if the spar is the same height as the tip or if it is on the bottom of the ribs. If necessary you'll need to cut the spar off at the rib, cut the rib end slightly so it will meet up flush with the butt end of the spar, and cut tip end also. Its a lot easier to do than explain.

One thing you'll need to watch for is the spar being below the covering. There should be a smooth compound curve from the rib to the wingtip with the spar structure not showing.

FlyWheel 01-14-2014 03:58 AM

3 Attachment(s)
I had some errands to run today, so I didn't get much done. I did get the end pieces on though. I was given a suggestion, I forget by whom or where it was posted (sorry), which not only looks like what was done on the actual plane, but will also make sanding the underside a lot easier.

Attachment 172874

Here's what I did. I wet the .125 x .125 end pieces and bent them, pinning them to the board and letting them sit until they were dry, holding the bend.

Attachment 172875
(The rib pieces with the clothes pins holding them are the wing roots,
which are two ribs laminated together)

Then I glued it in place, along with the other components of the wing ends. When I sand everything I will sand down the end of the spar to blend into the end piece. The end of the wing will hold the same curve as the rest of the undercamber, with just a slight droop on top, as is pictured on the original plane.

Attachment 172876

I'm sure a lot of you are wondering why I'm progressing so slowly. One, I'm using TiteBond, which means I have to sometimes stop to let parts cure before proceeding. This is fine by me because Two, This is a slightly more advanced model than I have built before, and the slow cure gives me a lot of time to make sure everything is right (or fix it if it isn't), and Three, I like to build, so why rush the fun?

And I finally figured out how to embed the attachments into the post!! [popcorn]

FlyWheel 01-15-2014 11:41 PM

4 Attachment(s)
Finished the wings, at least the fabrication of them; I haven't sanded them yet. I got the wing root pieces attached and angled correctly, then let tem sit while I did some food shopping.
Attachment 172884Attachment 172885

When I got back I gathered some some of the harder balsa from an older kit and made the braces for the wing wires, which are supposed to hold these things onto the fuselage. Then I made the support cable blocks. These hold the guy wires that stretch from the wings to the masts and (hopefully) keep the wings from folding in flight. The instructions say to make them from .125 x .187 balsa with a .031 hole drilled lengthwise through them and the .125 x .187 spar they are glued on top of.

Yeah. Right! :roll:

I got out some .250 x .250 hardwood stock, cut it to size, drilled and mounted it to the side of the rib where the spar intersects it instead. Might add a little weight, but I think these wings can afford it.
Attachment 172886

Even with the heavier wood they still come in at way less than an ounce. That's one ounce. For both of them. COMBINED!! ::o
Attachment 172887

FlyWheel 01-19-2014 04:17 AM

4 Attachment(s)
Today went a lot easier, mainly because there were no laser cut parts, everything was cut by me. Today's construction was the empennage (A.K.A. the 'tailfeathers'). This is where I really start redesigning. I start with the rudder. The kit has a fin and rudder, however the actual plane had a full rudder. Photographs and drawings of the plane do not show the actual construction of this control surface, but Tritle has the rudder section as an open framework (a VERY open framework) and a solid fin, with the option of drilling out holes to lighten it. I decide to keep the solid fin for structural purposes, and beef up the framed section a bit.
Attachment 172968
The two will be joined together with some sort of rod wedged between them for the full flying rudder to pivot on. I'm thinking perhaps alumin(i)um? Although wood would be easier, as I do have to add arms for the pull-pull system. The plan shows these threads attached about a third of the way up the rudder, but the photos and drawings of the actual plane do not, which is understandable because in that location they would interfere with the operation of the rudder. In fact, none of the pictures or drawings show the control cables at all, maybe they were contained inside the fuselage (I could also put them underneath)? ????

I also used the harder balsa for the outer perimeter of the framed section, and added gussets on all four corners as the ribs were only made of .125 x .062 balsa!

The horizontal stabilizer and elevator were modified slightly as well. Again, I used the harder balsa on the perimeter, and I also substituted the .125 x .187 for the trailing edge of the elevator with .125 x .250 so I can better taper it. The leading edge is made by laminating two pieces of .062 x .062 in a curve, so I left that as it is, as a laminated piece would be stronger that a solid one.

Attachment 172969

In addition I added gussets both at the corner trailing edges of the elevator and at the second ribs, as I will be adding support 'cables' there as per the original design.

Attachment 172970Attachment 172971

FlyWheel 01-20-2014 09:56 PM

4 Attachment(s)
I started on the fuse today. After checking the few cut parts for uniformity I built up the frame work. I decided against using the harder .125 x .125 from a previous kit for the longerons, as I found out the plan calls for them to be made by laminating two .125 x .062 sticks together, and I decided laminated longerons would be stronger than solid ones.

Attachment 173001

The side panels are in two sheets which had to be glued edge to edge (why? I have no idea. They have sheet balsa that wide and it certainly would have fitted in the box). I actually did this first then let them dry while I built up the frames. Take note, these have to be assembled in a particular way, as one end of the rectangular top piece is at a very slight angle to match the prop angle of the front end, and this angle is very slight.

Attachment 173002

By the time I was done with the frame the side panels were dry enough to take off the board. I drilled the wing-wire holes...

Attachment 173003

...and glued them onto the frames. Once I was sure everything had set up sufficiently I unpinned the fuse sides and glued on the wing doublers.

Attachment 173004

Next step I believe is to assemble the two sides into an actual fuselage! [popcorn]

gramps2161 01-20-2014 10:21 PM

I have been following along, and your build looks great. Boy I would be breaking a lot of those small pieces. I got away from the CA glue myself love the yellow wood glue plan it out right and you can get quite a bit done at one time.

thepiper92 01-20-2014 10:40 PM

Very difficult looking build, much more so than my p51. I agree with Gramps, the wood glue is much easier to use. In the plans for my p51, it stated to not glue and only put the parts together. With wood glue, I was able to glue right away, and be able to tweak parts here and there while assembling, before the glue dried.

FlyWheel 01-25-2014 09:17 PM

1 Attachment(s)
Sorry I haven't been doing any building recently, We have been cleaning out the garage/hanger, getting rid of a bunch of my room-mates old junk. I also got myself a set of modular drawers to better organize my 'miniature aeronautical fabrication supplies'.

FlyWheel 01-26-2014 10:59 PM

3 Attachment(s)
Time to put the fuselage together, which is turning out to be both time consuming and tricky. First, the instructions say to glue two or thre parts on, then wait for them to dry. Then glue on two or three more, wait for them to dry.
Attachment 173100

Which is probably a good idea, as this plane isn't known for it's structural integrity. Nor, it seems its method of construction. Maybe it's my inexperience, but it seems this thing could have been done better.
Attachment 173101

The firewall was the hardest, as not only is there no way to pin the fuse to the plans to hold everything in place, but the sides have to be bent inwards and somehow held in place as the glue holding both the walls bent and the firewall in place between those walls all at the same time cures. In fact, all the parts involved in this part of the construction of the fuselage involve solving this dilemma; how to hold something together without being able to pin it to something. I finally came up with the idea of using the finer pins to hold them in place, much as a surgeon would pin broken bones in place. So far it seems to be working.
Attachment 173102

It also seems my light spackle has disappeared, so I'm going to have to pick some up.

FlyWheel 01-27-2014 10:12 PM

4 Attachment(s)
I think I know why this build is considered to be of an intermediate skill level, you have to know hot to re-write the instructions! If I had to do this over I would have ignored the upper fuselage formers when they said to install them, and just put .125" x .125" braces in their places instead. Because the top formers do absolutely nothing for yesterdays or today's entire construction except get in the way making this part of the build very difficult.
Attachment 173119
An extra .125" x .125" cross brace which I added because I don't believe the flimsy .062" thick former plane will cut it! The bead of glue along the inner fuselage column was added as per the instructions along the line were the fuse side was 'cracked'.

Today consisted of attaching the cross braces (nearly all .125" x .125" pieces), the rear deck and front braces, which, as I pointed out would have been a lot easier to do if the top formers were not there as I could have laid the fuselage flat on the plans on it's top as well as on the bottom; note how the front is hanging off the end of my build table in the last photo. doing this would have made installing the firewall a lot easier too. Oh, well, live and learn I guess. I hope anyone else who has one of these Tritle kits still sitting on their 'to-do' shelf is reading this and can benefit from my shortsightedness, at least. :roll:

tobydogs 01-28-2014 01:02 AM

flywheel,your making good progress on this build,i also agree it looks like a difficult build and fragile to handle. I'd be breaking pc's with my clumsy hands:rolleyes:.

how will you cover this plane?[popcorn]
glad to be suscribed!

FlyWheel 01-28-2014 01:23 AM


Originally Posted by tobydogs (Post 938265)
flywheel,your making good progress on this build,i also agree it looks like a difficult build and fragile to handle. I'd be breaking pc's with my clumsy hands:rolleyes:.

LOL, Been there, done that. :oops:


Originally Posted by tobydogs (Post 938265)
How will you cover this plane?[popcorn]
glad to be suscribed!

Covering of the fuse front (cockpit area) will be regular film covering (UltraCote, probably), something that looks like sheet metal, as photos of the actual plane indicate the front of the actual plane was metal, or metal covered
(alumin(i)um?). The front end should be strong enough to handle regular film, especially as covering sheet balsa requires almost no shrinking.

The rest of the bird will probably be something like PolySpan. I even got a trim iron for the extra heating control I will need.

gramps2161 01-28-2014 01:57 AM

FlyWheel it is looking great nice neat build build you have going. Stinks that you followed the plans and it is making it more difficult to work on. Nice that you pointed it out to save someone else the headache though.

I second that fragile bit as I would be making a few new pieces myself.:)

FlyWheel 01-29-2014 07:14 PM

1 Attachment(s)
Didn't get much done today, I need a tool I don't have; a pair of fine yet sturdy needle nose pliers to bend the tine loops in the wire to make hooks for the guy lines. I did get the support pieces for the V-stab installed at least. Other than that just some preliminary sanding of the wings.
Attachment 173146

Oh, and here's another reason not to glue on the turtledeck formers when the instructions say to: The second former, to which the upper kingposts are mounted if left off could make building them a lot easier, as it could actually be built on the former, which could then be assembled onto the plane as a single piece.

Probably the hobby shop would be my best bet, it would cost a bit more there than Lowes, but I'm going to need to look into electronics, motor, prop, covering and probably order some PolySpan anyway (if they can get it). I also want to look at potential pilot figures. Any one know of a 1/8 scale 1900's style pilot (extra points if he has a handlebar moustache)? :tc:

FlyWheel 02-04-2014 07:10 PM

I went to the hobby shop today, found a perfect pair of hobby sized but sturdy pliers, some silver UltraCote for the cockpit and got a .060 CF rod and .060 I.D. tube that I will use to hinge the FF rudder (I'll sand the rod so it will turn better). They were not able to supply the 2208-34 motor or the PolySpan, so I'm going to have to get those online. Unfortunately I forgot to look for a pilot figure, but judging from what I've seen online, I doubt they would have had anything anyway. I may just end up buying a doll and surgically alter him to fit. That would probably work better anyway because I could then fit him to the plane. Also I can choose what he will wear.

I also found some #12 swivels that look about right at the hunting and fishing store which I will use for the main wing support wires. They look sorta-kinda like teeny turnbuckles. Scaled up they would be probably be about 8-9cm long; a bit big, but any smaller and hooking them on may become difficult.

FlyWheel 02-05-2014 09:53 PM

I shoulda done this a long time ago!
5 Attachment(s)
Bent the .031" wire into a small double hook for the King Post, Then bent the alumin[I]um tubes for the wing wires. But when I went to install them in the plane I immediately saw there was no way I was going to be able to work my fingers around those d@m^ formers. So I did something I should have done a long time ago, I carefully cut the two forward ones off! Without the formers in the way, installing the tubes was simple!
Attachment 173280

Of course, now that it was free to work with, I was also able to build the kingpost on the former. It also meant I wouldn't have to struggle with mounting a more fragile king post to an awkwardly mounted former later! Doing it 'by the book', I would have just glued the ends of the two dowels together, with the hook held on top with thread wrapped around them, a'la jungle native wood bridge style; albeit with an epoxy coating. What I did was place a small .125" x .063" sliver of balsa in between the two tapered ends and glued them together.
Attachment 173281

While it cured, I got out the two pieces of 3" x 4" x .063" pieces for the hood cover, only to find the two pieces which, pieced together and bent were supposed to fit over the laser cut formers were in fact too narrow. So I did some measuring, got out some .063" sheet from my scrap bag and cut my own instead (which took a while longer than I thought when one of the dogs tripped me up and I broke them. After getting everything cut to shape, of course. So dog gets locked out and I cut another set.
Attachment 173282

By this time the king post was cured enough, so I un-pinned it, trimmed the balsa sliver, drilled out the hole for the hook (using a pin) and mounted the hook. Dabbing some epoxy on it to hold it in place, I will let it cure overnight ('20 minute' epoxy takes a lot longer than that in cold weather) and tomorrow I will add the thread and epoxy reinforcement.
Attachment 173283 Since I will be making the front cowling out of balsa, AND making it removable so I will be able to access the motor, I also soaked, bent and laminated a pair of .125" x .063" strips. I will glue this onto the front of the forward former, beveled to the correct angle to support it.

I then plopped the two hood cover haves into the water. I will let them soak overnight and bend them to shape tomorrow, letting them dry to retain that shape. This should make fitting them on a lot easier. I plan to do the same with the front cowling.
Attachment 173284For cutting that to shape I will have to have the front former in place, however.[popcorn]

FlyWheel 02-06-2014 08:47 PM

3 Attachment(s)
Not much done today. I wrapped the kingpost top with thread and dabbed on some 20 hr epoxy. Well, 20 minute, actually, but the weather is cold so I know it'll take a lot longer than that!
Attachment 173298

Also got the mounting pins put into the wings and blocked them on. I also used epoxy there, and everything is clamped and curing.
Attachment 173299

I'm a little concerned about the upcoming landing gear though. The instructions (which are backwards, of course) say to bend them out of .063" music wire and solder them together. Can this be done with an electrical soldering iron? I don't have a torch nor do I know how to solder that way.

Maybe I should just forget the wire altogether and just make something out of hardwood.

Abuelo 02-06-2014 09:16 PM

1 Attachment(s)

Originally Posted by FlyWheel (Post 939350)
Not much done today.

I'm a little concerned about the upcoming landing gear though. The instructions (which are backwards, of course) say to bend them out of .063' music wire and solder them together. Can this be done with an electrical soldering iron? I don't have a torch nor do I know how to solder that way.

Maybe I should just forget the wire altogether and just make something out of hardwood.

You should be fine using what you have.

The wire is 1/16" so the iron will heat them OK and electrical solder is fine. I suggest getting the wires in place, wrapping the joint with one or more strands from a multi-strand wire (depending on how neat a joint you want) enough to hold them together, and then soldering. Its also OK to use some separate rosin flux if you have it, and sand/file the wires through the oxidation/coating to bare metal.

When done, mix up some baking soda and water and apply the paste to the joint. Scrub with an old toothbrush to get any excess rosen spots off and to brighten up the joint. Its also OK to file off any protrusions.

Photo shows a functional if not aesthetic soldered landing gear joint.

FlyWheel 02-06-2014 10:54 PM

That's what I was hoping, thanks. And yes, I do have a 'can' of flux, I found that adding it separately before soldering works a lot better than depending on whatever flux they put inside the solder wire. My iron is adjustable up to 50 watts, I hope that's enough.

fhhuber 02-06-2014 11:31 PM

Don't forget to rub the music wire with steel wool in the area to be soldered...

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