debspersonaldogwalker

Greetings! I would like to create my first build thread along with my first Balsa USA (BUSA) kit. It's one of America's WWI biplanes. I'm re-entering R/C building and flying after about a 6 year lay-off. I started with gliders and a rubber powered model in the mid-1980's. I've built and flown a Royal ARF trainer, the Sig Smith Miniplane, the Tower Kaos, the Top Flite Elder .40, 2 Sig Hog-Bipes, the Great Planes ARF Space Walker. When the Royal trainer's fuselage was a wreck I designed and built a replacement with bigger tail control surfaces and it became a taildragger. I designed, built, and flew a .40-size model very similar to a Space Walker. Currently I'm flying the GWS foam F4U and Pico Tiger Moth. I'm flying the Sig Astro Hog, Pica Bucker Jungmeister, Great Planes ARF Tiger Moth, and Electrifly Flatana. My gliders have included the Goldberg Gentle Lady, the Airtronics Olympic 650 and Olympic II, several Bob Martin Bobcats and *****cats, three of the Dynaflite Sensor 117s, a scratch-built Schweizer 1-26B in 1/8 scale, a couple of Great Planes Spirits, and a few scratch-built slope models, one of which looked quite a bit like a hawk in flight.

This will be my first WWI model. I hope to add some of the exterior scale features to the Tommy such as the elaborate exterior tail bracing and control cables and the flying and landing wires for the wings. I enjoy building and during my years as a carpenter I'd frame with 2x6s during the day and with 1/8 x 1/4 balsa sticks in the evening. I'm not a scale modeler and my aim will be a model for flying that will look good on those low, slow passes.

The kit was ordered Sunday online and the Big Brown Airplane truck dropped off a box measuring 41-1/2 x 8 x 4-1/2 inches today. The box weighs about 6-1/2 pounds and the finished model should weigh 6 to 7 pounds.
Some specifications:
Both wings span 53 inches
Wing area 1016 square inches
Fuselage length 40-3/8 inches
Weight 6-7 pounds
For .40-.45 4-stroke glow engines

I'm considering electric power since I don't have that size engine and I don't enjoy the oily mess, especially on a complex model with lots of wings, wires, and stuff hanging out in the breeze. So, I'm looking at 7 pounds at 75 watts per pound being 525 watts for reasonable power. I want to stay within 4S batteries because of the charger I have (Revolectrix 4S Cellpro). I'm thinking a 2500-3200 mah 25C battery would provide "realistic" flight performance. I'm new to this electric power so advice is welcome.

debspersonaldogwalker

I'll describe the kit. There is a cardboard tray above the wood that holds the rolled plans, parts bags, catalog, and instructions separate. The plans are 2 sheets measuring 7 feet by 30 inches. The instruction book is 72 pages and sounds written for a novice builder with full detail on what tools and adhesives to use. Techniques are explained. I would recommend this kit for "intermediate" level builders and pilots. A sheet of cardboard boxes off the ABS cowl and some soft balsa blocks. The 6-7/8" cowl is the nicest I've seen with smooth edges and a satiny surface.

The rest is wood and lots of it! There appears to be a lot of variance in wood weight and grain and it has been selected and used carefully to get the right type of wood for each piece of the kit. The sticks are grainy, the blocks almost free of grain and light. The die cutting looks very good. I don't expect each and every piece to drop out of the sheets but many do. I saw a minimum of "die crunching", just a small bit on a couple of parts. The sticks look nice and straight. I'll give the wood parts quality a grade of A.

Construction appears to be scale-like with sticks used almost everywhere. An inch of sheet is applied to the wings leading edge tops. I'd call this model "sport scale" meaning it is meant to be flown and look good in the air. The design seems good given the compromises desired for lightness, ease of construction, ease of flying, and affordability. No mention is made of a windscreen, flying wires, or other scale details.

I like building the fuselage best so I'll start with the flying surfaces. I'm going to build the bottom wing first as instructed as a center section and two wings. Then I'll build the one-piece top wing on my 48-inch board by hanging one end off the end and then relocating the plan and finishing the other wingtip.

The tail surfaces are simple 3/16 thick stick construction with an interesting detail. The surface outlines are made of two laminations of 3/32 x 1/2-inch balsa. This allows the builder to simply sand grooves for the hinge slots before laminating. It also allows the corners to be overlapped for better strength.

This kit looks like it'll be a real pleasure!

debspersonaldogwalker

The diecutting picture is of the back side of the sheet.

oldtyme

I almost bought that kit! I opted for the 1/6 scale BUSA Sopwith Pup but I will be following your build with great interest. I am planning on building mine this winter. This will be my first WWI plane as I usually opt for WWII birds. Looks really interesting and I can't wait to start and am anxious to see how your build goes.

Cheers,
Andy

debspersonaldogwalker

Well, ribs have all come out of the die-cut sheets easily. So far, all the spar slots are perfect. I've assembled most of the bottom right wing by simply gluing the parts together. This photo shows the 1/8"x1/2" inner leading edge being glued using an oak sanding bar as a clamping fixture. I use Titebond when I want a longer setting interval and am using medium CA for quick joints. A plywood stick is used as a spacer to provide the proper gap between the strut carrying ribs.
A Saito .40 engine was won on Ebay yesterday evening and will be fitted to the Tommy. Hopefully it'll get her off the grass here at 6400 feet.

GaryHarris

Ill be following your build since I have considered this kit before, but if it were me, I would have to go with a 4 stroke over electric. Just my opinion, but a plane of this quality deserves an engine.

debspersonaldogwalker

Here's the leading edge cap being glued with Titebond. Once again the sanding bar and clamps are used, with the carpenter's level holding the wing panel flat on the board.

ARUP

Subscribed! Neat airplane!

debspersonaldogwalker

Here's the overlapped construction of the laminated wingtip. The last rib is installed as drawn, it is located beyond the leading edge length. The block at the end of the leading edge came up short so 1/8" of filler was added between the last #7 rib and the block. Balsa USA says in the instructions to go with the parts as cut instead of the plan drawing since paper can change in dimensions but I decided to build the wing tip to the outline as drawn. The instructions to this kit, BTW, tell just how to put the kit together each piece by piece. While some kits assume the builder has skills and experience this one is written for a novice.

debspersonaldogwalker

Am finishing the bottom wing panels, adding shear webs and shaping the edges. You are warned the plans may have shrunk or expanded due to humidity etc. and sure enough my wings came out 1/8-inch different in length. I've trimmed one at its inner end to even them up. Sanding the top front spar to match the ribs is a bit awkward. Thanks to the straight long pieces the panels are looking very straight and true. I'm hoping to finish both wings this week.

Kmot

My Feedback: (24)

I shall be watching this with great interest! Thanks for doing the build thread.

debspersonaldogwalker

This is the bottom wing center section skeleton, no sheeting or fillers yet. You build this much of it and then glue the wing panels on, creating a one-piece wing. There are three 1/16" balsa ribs, front and rear 1/8" liteply joiners, and 3/16" square balsa filler/spars. The joiners are cut with the dihedral angles. The bottom wing has dihedral while the top wing is flat.
I don't think liteply is a good choice for wing joiners so I've laminated with medium CA a 3/8" wide strip of thin carbon fiber. It will sandwich between the joiners and the spars and should provide more breaking strength.

BTW, Sig Koverall fabric has been chosen for the Tommy's covering since I have a huge sheet of it! It looks great on a biplane, I've covered a Hog-Bipe with it. Koverall is a polyester fabric that is attached with Sig Stix-It heat activated adhesive. You only paint the adhesive onto the wood areas you want the fabric to stick to. Then the fabric is ironed on like a film product, except for the very nice way it warps itself onto curved areas like wing tips. Primer and paint are also required. I've been trying to decide between the boxtop Navy Trainer color scheme and a "fantasy scale" scheme imagining a post-war surplus Tommy going into service locally delivering stuff to outlying ranches etc. Yampa Valley Flying Service is my concept in a cream and green design.

Kmot

My Feedback: (24)

Hey why not? Sounds cool.

debspersonaldogwalker

The bottom wings are being joined on a piece of laminate shelf that has a center line drawn on it. Weights are holding the wing sections onto the board. Reference marks are inked on the wing and center section ribs half-way between the front and rear spars. Pieces of balsa are used to raise the wing tips and the dihedral is measured at the wing tip ribs with a piece of balsa cut to the specified 7/8-inch height. With the reference marks vertical over the line and the dihedral set properly the rear joiner was then glued to the wing spars. After rechecking the alignments the front joiner will be glued.

debspersonaldogwalker

The bottom wing ready for the top sheeting on the center section. The bottom sheeting is installed along with front and rear filler blocks for the wing mounting bolts. A filler piece at the front spar and trailing edge pieces are installed. The top 1/16" balsa sheeting will complete the center section.

While the kit contains five center section W8 ribs and the instruction booklet shows installing five, the plan shows seven with the extra two added to the dihedral joints. I decided to cut those two from the die cut sheets the other ribs came from and have more wood there for covering attachment.

On to the 53" top wing which is built in one piece. Since my board is only 48" I'm planning to build most of it with the spars hanging off one end of the board, then move the plan and finish the other wing tip. All the full length spars and leading edge material are produced by splicing additions to 36" material supplied in the kit. As shown in the instructions, these splices are easily made using a razor saw. The two pieces are stacked and cut at once. Minor adjustment is sanded and the joints made while holding the pieces along a yard stick.

buzzard bait

Don't know how far you want to go with the details, but the top wing was actually built in two halves, so doing that with yours would be scale. There was a gap, which is exaggerated in the picture because the fabric stretch distorted the frame over the decades...

buzzard bait

I live in Ithaca, NY where these planes were built; a group here is restoring one. The BUSA kit is of course a sport scale model, but if you want to make it more scale it shouldn't be hard to improve. I think the most noticeable deviation is the landing gear...BUSA likes to widen the gear to make take-offs easier. Here are a few more pics...lots more available if you're interested. Good luck how ever you decide to build it...should be a beauty in the air! Jim

debspersonaldogwalker

Thanks a lot, BB, I'll keep your photos in mind! I do intend a sport model for flying from grass, but with a little more detail. The wider landing gear sounds just fine to me. The seam on top of the wing sounds like a perfect little detail, however, very visible and simple to do.

Working on the top wing now and really, the die-cut parts are of nice wood, well cut, and fitting very well. BUSA's attention to detail makes this kit a real building pleasure!

debspersonaldogwalker

Most of the upper wing is assembled. It went together with a very little adjustment to the spar notches in the ribs. The left wingtip was hanging off my short building board. So now I'll move the plan and finish that wingtip before sheeting the leading edge. CA was used for all these joints. You may notice the splice in the aileron trailing edge. It was caused by my cutting the wrong piece of wood for the wing trailing edge. Reading the instructions would have prevented this mistake.

While the wings are both 53" in span the upper chord is 11" while the bottom wing spans just 8-1/2". There is no hardwood, the spars are balsa. A couple of strips of 1/16" birch plywood are the "hardpoints for the cabane strut attachments. Paper tubes were inserted as servo lead conduits. The ribs were die-cut with holes for the servo leads, a nice touch.

I was flying my Great Planes Tiger Moth today and seeing it slowly glide across the sky got me eager to get this Tommy going!

debspersonaldogwalker

The upper wing is sheeted with 1/16" balsa for about the center 4-1/2" of span, the same as the lower wing. Trailing edges are pre-shaped balsa. The leading edges are sheeted on the top only.

R8893

My Feedback: (20)

I have built 4 of the BUSA WWI models and feel that the "hard points" for strut mounting leave a little to be desired. I have added reinforcement to all of them but still have had some failures, ie.,broken glue joints. There is not much glue joint area where the 1/16th ply meets up with the spars or thin balsa ribs. I do have to admit that my models are flown pretty aggressively. I also add some wood to capture the blind nuts so they don't fall out inside the wing.
Chuck

debspersonaldogwalker

Thanks, Chuck, good points. There is some hard 3/32" wood in the diecut sheets I'm thinking could be laminated onto the hardpoints. I intend to fly the airplane in a "scale-like manner" and of course there will be some dumb-thumb incidents.

4deltagolf

great build thread, over the last year i've been building one my self. at the fuselage and stalled trying to decide on engine. moveable fire wall makes this choice very important. magnum has developed a .56 gas engine but not selling yet. i may wait for that

buzzard bait

In size and weight, this plane should be pretty similar to my VK Nieuort 17. It is 5 lbs 6 oz and has a 54 inch wingspan. It has less wing area because the bottom wing is very small...much smaller than the bottom wing of the Scout. Of course, the key is to keep the tail as light as you can, and mount all the necessary weights as far forward as possible. My battery box is in front of the firewall and servos and Rx are right behind it.

I have found it flies very well with much less power than the usual recommendations for these planes. With a PAW diesel swinging a 13x6 prop at about 7500 rpm, the plane has more power than it needs. It will do loops, rolls, climbing turns etc. just fine. For glow engines I think the best choice is a mild 40 - 46 capable of swinging a 12 inch prop. That would include the plain bearing OS LA 46, TT GP 42, or many older glow engines. I'm planning to use an old Enya 45 from the 1960s on my Fokker Dr. I in this scale, because it will swing a 13 inch prop. You don't have the hassle of trying to fit a long 4 stroke under a short cowl.

These planes are so much fun, I'm sure you will really enjoy it. Small enough to keep in one piece, and they fit easily in most cars. Fabulous in the air. When I'm flying the Nieuport, I wonder why I bother with anything else but 1/6 scale models of old airplanes!

Jim

debspersonaldogwalker

I get a lot of pleasure from flying a GWS Pico Tiger Moth just at sunset, when the field is shadowed but a hundred feet up the tiny bipe is still catching the sun, floating around like a feather. That plane will barely climb, but in a couple of minutes it's looking pretty small. The Tommy's getting a Saito .40 and I'll be trying props in the 11x5 and maybe 12x4 range. It will turn a 10x6 Master Airscrew at 10,000 here at 6,400 feet. I'll either need a very short fuel tank or have to move the top of a former back, the one at the leading edge.