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invertmast 02-10-2012 09:05 PM

Mod'd Hostetler 1/4 GeeBee R2
3 Attachment(s)
I have begun the redesign of the 1/4 Hostetler GeeBee R2. This is basically the test model for me, as I am making many changes to enhance its scale accuracy (over-all the only thing accurate about it, is the fuselage shape forward of the canopy, and the wing outline). Once the airframe proves to be accurate (through scale competition), I will use the modified plans to begin building a 50% version mimicking the full-scale's construction (that means welded steel tube fuse with wood bulkheads for the shape).

Anyways, for documentation, I started off with the following Books:

"GeeBee" By Delmar Benjamin and Steve Wolf
"Gee Bee The real story of the Granville brothers and their marvelous airplanes" By Henry Haffke

Plans are from Hostetler, but I also ordered the Henry Haffke 1/4 GeeBee R1 plans from AMA and the vern Clements 36" wingspan Gee-Bee R1 plans from AMA.

I purchased all the plans to see which ones "agreed" with the Benjamin R2. Hostetler's were the closest resemblance in most instances, but will need many modifications to make them accurate.

First mod needed is the wing:
The Plans as drawn use what appears to be a modified Clark-Y. The original had a Very thin and reflex'd "Naca M6 @ 65% thickness". Using Profilli 2 i'll be re-drawing the wing to incorporate this airfoil. This will increase the take-off and landing speeds, but is a necessity because the airfoil as drawn is nearly twice as thick!
The original wing also has a 3/8" bass-wood plug that is glued into the outer wing panels and goes all the way to the center of the fuselage (about 12"). Since the model will incorporate functional (and scale!) flying wires, these large "plugs" won't be needed. I'll probably just have them go into the center stub wing about 6". The reason for the elimination of the huge plugs, is they are no longer supporting the majority of the flight loads. With the addition of functional scale flying wires, they will transfer the flight loads to the fuselage instead of the plug spars.
The landing gear mounts will also need changing to accommodate the Sierra scale struts.

Fuselage Construction:
As drawn, the fuselage is built with a pair of light-ply sides that are "curved" to follow the outline of the side of the fuselage. I REALLY hate building "curved" fuselage parts b/c they are nearly impossible to get perfect on both sides causing big flight problems due to an inaccurate shape.
So to fix this issue, i'm going to build up a 1/4" sq Balsa/spruce structure similar to the welded tube fuselage of the full-scale. This will allow me to incorporate hardwood dowels in the cockpit areas so when looking inside the door (which will be functional) and the canopy, it will actually appear to be welded tube.

Landing Gear:
As drawn, the plans show the Byron P-51 Gear struts epoxied into a hardwood "block" in front of the leading edge. This block is pretty substantial (in weight), and the Byron struts are no longer available (and wouldn't work with the flying wires anyways).
I'll replace the giant hardwood block with some carbon/ply laminates. The functional flying wires will also attach to the gear struts and the wheel-pants will be 2 piece and the lower portion will split from the top half so it "floats" with the oleo action, again completely scale.

Control system:
I'm not even going to THINK about letting any control linkages be exposed on this model, it would just completely Ruin the looks of it! So all the control linkages will be completely concealed. For the fuselage and rudder, this is fairly simple. The problem comes with the wings.
Due to the thin nature of the wing, not many servo's are capable of fitting (the thin wing ones would, but i'm wanting some substantial torque for these ailerons). So to solve the problem,i'm going to replicate the full-scale design. I'll take some aluminum rods and drill 2 holes in it. These holes will be tapped for a 4-40 bolt and then this will slide into a brass tube epoxied into the aileron. The aluminum rod will be supported in 2 bearings in the outer wing panel and the rod will be cut in 1/2 along its length for about a 1/2". This will then slide into a brass tube into the stub-wing (which will also have a aluminum rod inside the tube cut in half lengthwise for about 1/2") and supported by a few bearings. the opposite end of the cut will be tapped for a 4-40 bolt and setup for a Push/pull linkage from the aileron servo. When the wing is slide into the spars, the 1/2 rods will engage each other which will provide a completely hidden aileron control linkage.
I know it sounds complicated, but this has been used on some full-scale airplanes and works great. Its easier to show than explain, so be patient for the build!

Horizontal Stab:
Its not even close to being accurate in outline. The span is to large, the root chord is to small, the LE sweep is to shallow, the elevators are the wrong shape.. Its just WRONG. So it will be completely re-designed. Oh, its also 1 1/2" to high on the fuselage, so this change will be incorporated as well.

Vertical Fin/Rudder:
The vertical fin is drawn with no offset. Thats not scale, so the off-set will be incorporated into my model. The Rudder LE shape is also to "fat" from the cockpit "rail" and above, so this will be re-done as well. The Vertical fin LE is also tapered to much and should be more rounded along the top. The Rudder side view shape is "close", but the point at the bottom is to rounded (and to large) and the curve along the top 1/2 of the TE is to gradual. Again, lots of mod's to the tail section. The turtledeck behind the canopy is also oddly shaped and not accurate.

I'm not completely Sure how i am going to go about doing this. I've been thinking of using Stits Lite but not sure. The full-scale was completely covered in fabric except where metal panels were. Even the solid plywood sheeted wings and tail were fabric covered and sanded extremely smooth. I may skip this part and go with fiberglass since their won't be much of a difference at such small scale.
The Fuselage stringer area definitely has to be covered in fabric though. This poses a unique problem. Their is a mixture of fabric and sheet-metal panels on the fuselage. So i have to figure out how to replicate this without a "ridge" where the fabric and whatever else meets... Anyone used Stits lite? Got any suggestions?

As far as the particulars for the model, here we go:
Graphics will be from someone (probably just do paint masks and paint everything).
Power will be from a Seidel ST7-70 radial engine (the one off my FW-190). unless of course the engine sells, then it will be with the new Evolution 99cc radial
AR9000rx w/ a Powerbox switch and A123 rx battery
JR servo's

After going to three different places over 2 days, I finally found a place that was able to copy the plans for the geebee... unfortunately they had to cut them to fit their scanner... So the re-design and building can begin.

First up was changing the inner fuselage "structure". Hostetler has you build a pair of full-length fuselage sides from 1/8" balsa laminated with 1/64" ply on both sides. These are then "curved" and placed down the center of the fuselage and balsa spacers used to hold the curve.

I personally don't like that curve (you can see the "orange" on the top view of the fuse, this is the original outline), as it will make things a bit difficult to keep straight..

Attachment 2236611

So the inner fuse plate (for lack of a better term) will be built up from 1/4" sq. spruce, balsa and balsa sheet. I believe this will be just as strong and lighter than the as drawn setup. The pink outline on the top and side view.
Looking at the top view of the plan, the inner structure is parallel to the center-line from the firewall aft to the instrument panel. the sides then taper back to the last bulkhead.
The outer bulkhead templates were then modified so they fit the new fuselage plate. Their will be 1/4" sheet balsa in the area where the wing carry through spars pass through the fuselage. This can't be figured out until I have the new wing ribs drawn up.


A quick photo of the landing gear. A quick phone-call to Darrell this morning and the tire issue was figured out and resolved, once he gets the smaller 5" tire in-stock he's going to send me those tires.

Attachment 2236612

Also while re-drawing the fuselage structure, the stab was checked and as drawn on the plans it is 1 1/2" to high on the fuselage, so the new position was drawn. I also started checking the dimensions and shape of the horizontal stab in relation to the 3-views I am using, and was appalled at how far off it was. The span is 4 1/2" larger than it should be, the LE sweep isn't steep enough, the root width is to narrow....
Over-all, the entire horizontal stab and elevators are going to be re-drawn.

Here's a photo of 1/2 of the stab and the 3-view showing how far off it is:
Attachment 2236613

xradarusa 02-11-2012 01:27 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
I have the plans for the 1/3 scale Hostetler R-2 and right on the plans it says that the 1/4 scale version was based on the Byron Gee Bee. It then goes on to say that the 1/3 scale version was drawn off of the origional and is scale except for a few deviations (airfoil, wheel size, fin offset.)

This is going to be just great and I am extremely interested in your progress. Please keep us posted.

invertmast 02-11-2012 05:31 PM

RE: Mod'd Hostetler 1/4 GeeBee R2


ORIGINAL: xradarusa

I have the plans for the 1/3 scale Hostetler R-2 and right on the plans it says that the 1/4 scale version was based on the Byron Gee Bee. It then goes on to say that the 1/3 scale version was drawn off of the origional and is scale except for a few deviations (airfoil, wheel size, fin offset.)

This is going to be just great and I am extremely interested in your progress. Please keep us posted.
I wasn't aware that the 1/3 was drawn off the originals. I was told that the 1/3 were just enlarged versions of the 1/4 scale with changes in wood dimensions to accommodate for the larger size. I also wasn't aware the 1/4 were based on the byron (or how in-accurate the Byron is) until I purchased these plans. The harold Haffke plans are much more accurate, but again they need changes due to the open structure building style.

xradarusa 02-11-2012 07:08 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
1 Attachment(s)
I went through and checked my 1/3 scale Hostetler Gee Bee for scale accuracy and it is farely close but not perfect. Probably any plan would have to be modified to some extent. Here is a pic of what my 1/3 scale Hostetler Gee Bee plan says on it.

invertmast 02-11-2012 08:24 PM

RE: Mod'd Hostetler 1/4 GeeBee R2


ORIGINAL: xradarusa

I went through and checked my 1/3 scale Hostetler Gee Bee for scale accuracy and it is farely close but not perfect. Probably any plan would have to be modified to some extent. Here is a pic of what my 1/3 scale Hostetler Gee Bee plan says on it.
It would be nice if he would say these things on his website. The source he sites in your attachment, is one of the Doc books i'm using..

invertmast 02-11-2012 08:34 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Well.. just wanted to say..

The GeeBee IS DONE!!!!!!!!!!!!


Just kidding... This is the new UMX GeeBee R2 from horizon.. Here's another picture of it posing with its big brother's landing gear strut:


I took today to finish the modifications to the plans, 4 hours of work later, the Horizontal stab is done (except for the ribs, these i'll knock off in profilli real quick):


And to show the difference between the "accurate" horizontal and the plans horizontal, here ya go:


The wing plans were modified for new spar locations (so they coincide with the flying wire attachment points), and the aileron outlines were adjusted. The plan drawn ones were slightly to narrow, short in span, and shifted towards the tip slightly to much.


Due to the extremely thin nature of this wing (about 1 1/4" at the thickest point), my control system will have to be sized a little different. Instead of the 1/2" rod, i'll have to use 1/4" and instead of the ball-bearing supports originally planned, they will have to be G-10 laminated to both sides of the wing ribs.

The Fuselage plan was also finished.. As you've noticed, when I modify plans like this I like hi-light the new structure area's as they are drawn so the lines don't get lost in the madness. I also make notes on the plans and hi-light them different colors so they are more noticeable.


And a whole stack of templates ready to be attached to their respective wood pieces and cut to shape.


ARUP 02-12-2012 04:56 AM

RE: Mod'd Hostetler 1/4 GeeBee R2
Nice! My 'fave' is Doolittle's, though.

invertmast 02-12-2012 07:55 AM

RE: Mod'd Hostetler 1/4 GeeBee R2



Nice! My 'fave' is Doolittle's, though.
The only difference between the R1 dolittle flew and the R2, is the number, cowling, engine and the lack of nav lights that were on the R2. Their were some small difference in the tailwheel, where the R1 was steerable and the R2 was locked. Otherwise they were nearly identical..

invertmast 02-12-2012 07:59 AM

RE: Mod'd Hostetler 1/4 GeeBee R2
Did some weight calculations so far today. With all the "guts" for the model, i'm at 15lbs worth of stuff. I am going to shoot for a 19-20lb flying weight (3 to 6 lbs less than advertised on the plans), so that leaves me 4 to 5lbs for the airframe, covering and paint. I think that should be easily obtained.

invertmast 02-12-2012 08:04 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
I decided to add some structure to the horizontal stab and modify a few bits...

The stab will be built with a 1/8" balsa "core". The ribs will then be cut in half along their chord line so as to remove a 1/8" section. The ribs will then be glued to the core and a 1/8"x1/4" spar will be installed, along with a 3/8"x3/8" LE and TE, then sheeted with 3/32" balsa. A slot was also added just infront of the TE so that the last fuselage bulkhead can slot into the horizontal stab locking the entire thing together.


A few hours of work later in the day and I've got the majority of short kit cut.. I'm waiting on my order of wood from National Balsa to show up so I can cut the last of the short kit parts (firewall, last fuse bulkhead, rudder false LE and a few wing ribs).


invertmast 02-13-2012 07:02 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
While still waiting for that wood order, I ended up finding enough scrap pieces around to nearly finish the entire short-kit. The only items left to cut, are the last fuselage bulkhead, which will be laminated with 2 layers of 1/64 birch ply with a 1/8" balsa core, a few ply wing-ribs, the Landing Gear mount plates and the G-10 rudder hinges...

So, 90% complete "kit"


Then I started to do some real work.. The stab cores are cut from 1/8" balsa sheet, and the wing ribs are cut from 1/8" balsa. Their is then a 1/8" thick section of balsa removed along the chord line of the ribs. the rear spar is 1/4" balsa glued on-top of the stab core, then the ribs and 1/8"x1/4" leading edge are glued to the core. I've got to put a portion of 1/8 balsa around the curve of the tips, put in the hinge blocks and then cover the ribs with some tape, then sand it all to shape. It will then be sheeted with 3/32" balsa, then flipped over and the process repeated.
The elevators are built using the same method, but using a 3/8" wide leading edge..


invertmast 02-15-2012 06:49 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Added some extra material for the hinge points to mount to.. the stab is going to extremely thin at the tip.. roughly 1/4"... On planes of this size I typically like to use the super robart hinge points (3/16") but with the narrow tip, thats not possible.. so I'll end up using the 1/8" robart hinge points. I don't think this should pose an issue, but the only other way around this, is to make G-10 hinge brackets, which may be a possibility to..

Since the H5 stab rib was also so small, to make that rib, i just installed a piece of 1/4"x1/8" balsa stood on edge and sanded it down to the airfoil shape using the rest of the stab ribs as a guide for the airfoil shape. The stab is now ready for the top side to be sheeted.


invertmast 02-16-2012 06:18 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Finished up the Horizontal stab this evening.. Over-all weight for the stab is 2.7oz not bad.. a little heavier than wanted, but not by much. Here's a photo with the stab with a 18" ruler and the firewall for sizing:


Then I got started on the Elevators. 3/8"sq. balsa for the leading edge and hinge blocks. 1/8"x1/4" balsa "ribs" and a 1/8" balsa core.


Then all the balsa parts from above are sanded down to shape in prep for the 3/32" sheeting. Here's a photo of the top of the elevators ready to be sheeted. When building parts like this, I don't sheet either side until i have enough time to build and sheet the other side to prevent them from warping.


Once the elevators are done, I'll have to make up the elevator joiner / control arm wire and its mounts and hinge the elevators, then makeup the hinge gap covers. I'll then glass all this before install. I'm STILL waiting on my "processing" order from National Balsa. If it doesn't ship by 4pm tomorrow, they will be losing my money. 11 days of "processing" on a simple wood order is not acceptable IMO with ZERO communication from them as for the delay.

hannes83 02-17-2012 10:25 AM

RE: Mod'd Hostetler 1/4 GeeBee R2
What a amazing thread!!

I like people who have the same heart for the Gee Bee like me.

Greetings from Germany,


invertmast 02-17-2012 07:44 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Finished work on both elevators and have them sheeted. All that is left for the horizontal stab assembly, hinging, gap seals and elevator control arm/connecting rod.


Then I started work on the rudder. Plans call for a 1/8" OD brass tube as a guide for the rudder hinge and a piece of music wire routed from the top of the fin through the tube as a hinge pin. I'm not fond of steel in brass, so I decided to use a piece of yellow nyrod pushrod material. Then a piece of music wire will be slid through it.
I then took the rudder ribs, glued them to the rudder false LE and then the trailing edge parts to the ribs, then slid the nyrod hinge bushing into place and glued it in.


I also cut the rudder hinges from 1/8" birch ply. I had intentions on cutting these from 1/8" G-10, but i ran out and didn't feel like waiting for an order. I also glued the nyrod hinge bushings into the ply pieces as well.

I would of sheeted the Rudder tonight, but of course I ran out of 1/8" sheet balsa, so I still have to wait on that stupid wood order, which "supposedly" shipped today.. They gave me a tracking number, but it hasn't be picked up, so i'm thinking they just sent me a tracking number to shut me up..


hannes83 02-18-2012 12:25 AM

RE: Mod'd Hostetler 1/4 GeeBee R2
If you need scale decals/markings feel free to contact me.

A friend of mine have positive and negative films in his computer for the complette R1 and the R2 decals!

You can see picture during we put it on my R1here:


invertmast 02-18-2012 06:02 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
I got a bit impatient today, so I went to the LHS and bought a little bit of wood, and then off to get a new set of band-saw blades to cut my own fuse stringers, oh and some robart hinge points.

Drilled the hinge holes in the elevators and stabs and test fit the hinge setup on those and rounded the leading edges.


Then took some 1/64" ply and made up the gap seals. The horizontal stab and elevators are now ready for final sanding and glassing:


Then i decided to sheet that rudder. After trying to sheet with the extremely soft 1/8" balsa I got from the LHS, I came to the realization there was no way it was going to get sheeted with 1/8" balsa. So I used 3/32" I also added some 1/8" sq hard balsa false ribs between the rudder ribs to support the sheeting as well (no pictures of them though).


Then I finished the rudder hinges and cut the hinge wire. Then test fit it all together:


Then I finished sheeting the top of the rudder and slapped it up against the plans to have a look-see. The bottom of the rudder will get a pair of carved balsa blocks that will be hollowed out. I "think" on Delmar Benjamins replica, their is the white tail nav light in this bottom portion.. if so, I think i'm going to put lights on mine :)


Then for that last fuselage bulkhead, i cut a pair of 1/64" ply bulkhead doublers, then using Gorilla Glue, I laminated these to the 1/8" balsa core, and put a piece of scrap melamine shelf board and some weight on it to cure over-night:


Then I laid out the fuselage plans on a ceiling tile in prep for starting to build the fuselage frame halves:


invertmast 02-18-2012 09:53 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Last update for tonight.. or maybe I should say, First update for today, since it is now officially Sunday. haha...

I decided to build up the 2 fuselage frame sides tonight. I'm in a building mood and not a Molding mood, so the F-14 didn't get waxed of anything tonight. I'm not looking forward to 14 hours of non-stop work to mold the front half of that fuselage top... I'll do it later

So, back to GeeBee stuff. fuselage Frames.. here ya go.. My new bandsaw blade has a messed up tooth, so the cuts aren't the greatest on the ripped down 1/4"sq. stringers... oh Well, Weight reduction :D


I cut all but 2 of the fuselage cross pieces, yea i know "whats 2 more to cut"... so sue me :)


Probably not the greatest picture.. But all of the fuselage stuff weights 1.7lbs.


Add in the horizontal stab, elevators and Rudder and your at 2.3lbs. The target goal of 5lbs for the airframe looks pretty promising to make!


And since I had a good bit of stuff built, I had to do a mock-up! **** that is one big firewall


invertmast 02-19-2012 01:49 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Time to start assembling the fuselage.

First up was drawing a center-line perpendicular to the short edge of the ceiling tile. The fuselage side frames were then tack glued to the firewall using a pair of carpenter squares to make sure they were 90* to the firewall. Then the 1/4"x1/2" balsa cross pieces were installed making sure the center-line of the cross pieces were installed on the center-line on the ceiling tile.


Then 1/4" sq. Balsa cross-pieces are added to put some extra rigidity into the fuselage frame. The Fuselage frame is now finished and can be removed from the building board.

For those wondering if all of the extra effort was worth saving a bit of weight, here's some numbers for you:

The Fuselage frame as seen in the previous photo is - 1.4lbs
The Firewall alone is - .8lbs
The lite-ply for ONE of the plans drawn fuselage side frames is - 1.9lbs. So 3.8lbs total for the fuselage side frames plus another .8lbs for the firewall. The "as plans built" fuselage frame would be around 4.6lbs.

So, I have saved in total so far 3.2 lbs over the stock airframe, NOT to bad at all.

And another mock-up with the Last fuselage bulkhead (yep, finally got it cut!) and horizontal stab/elevator:


invertmast 02-19-2012 04:10 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Epoxied in some Tri-stock between the firewall and Fuselage side frame and bottom cross member:


And after going over some things to find what I could do, i came to the realization that I need to permanently attach the horizontal stab in order to continue.

So the horizontal stab and elevators were final sanded and the bottom sides glassed. Hopefully i'll get the top sides glassed tomorrow AM, so that I can attach the stab tomorrow evening.


dasquirrelisme 02-19-2012 04:33 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Since that is just a test plane you can just send it to me when your done. Thanks :D

invertmast 02-19-2012 04:44 PM

RE: Mod'd Hostetler 1/4 GeeBee R2


ORIGINAL: dasquirrelisme

Since that is just a test plane you can just send it to me when your done. Thanks :D

Not a problem! Just send me a blank check before hand. Haha

allmetal plane 02-19-2012 06:16 PM

RE: Mod'd Hostetler 1/4 GeeBee R2


invertmast 02-20-2012 06:27 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Alright guys, you can all rest easy. I put firmly held the firewall with my left hand and grabbed the fuselage just aft of the long piece of 1/4" balsa along the bottom with my right hand. Holding the area with my right hand still and moving the firewall side to side (mimicking torque form the engine) the fuselage did flex some between my hands, and the aft portion of the fuselage above the stab slot moved in total 1/4". Once the stab is attached, that rear fuselage won't be able to move at all, then once all the other stuff is attached, that fuselage is going to be strong!!

Alright, back to work.

The top side of the stab/elevators isn't completely cured yet, so the stab will have to wait till tomorrow to get attached.

So I made up the elevator joiner wire. I basically used the same setup that I used on my FW-190 build. 5/32" music wire some 1/8" thick brass and a 4/40 heavy duty ball-link sandwiched between 2 brass plates. A 3rd plate and 3/16"OD brass tube act as a center "bearing" and support (I originally built two of these, but forgot to install the second one before bending the 2'nd portion of the rod).


I then finished sheeting the rudder. I thought i was going to have to use a balsa block for this, but I found some balsa sheet that was extremely flexible so was able to use sheet balsa.


After sheeting 1 side and before doing the other, I figured out i needed to strengthen the rudder "stinger" or else it would get broken. So I took a piece of .010" G-10 and glued it in the center of where the stinger would be, then sheeted the other side:


Then in order to hide the hinge pin once the rudder is installed, I cut a groove along the bottom Center-line of the rudder for the rod to ride in. I'm not sure how i'm going to keep it installed, but I may drill a hole and put a carbon tube in place, then a screw and washer to hold it into place, not sure.. anyone have any suggestions?


invertmast 02-21-2012 07:49 PM

RE: Mod'd Hostetler 1/4 GeeBee R2
Alrighty, Wood order arrived today... so it as time to get to work!

Spars are 1/4"x3/8" spruce. Two laid horizontally up front, and one vertical out back. The rear spar also tapers in height as it gets to the last 3 wing-ribs.

So with the bottom spar laid in position, all the ribs were pinned to the board, then the bottom spar glued into place. The forward spars butt glue up against the last wing rib. The upper spar also tapers between W8 and W9.


Then the Rear spar was cut and glued into position. As i'm building this wing, i'm making duplicate parts for the other wing.


Here is a shot of the basic wing framed up with the spars.


To help strengthen the rear spar since it will be drilled for aileron hinges, the spar is capped on the top (and eventual bottom) with 1/4" wide balsa strips, then these are sanded down to match the airfoil.


Then the 1/8" balsa aileron caps and wing ends are made and installed. To do this, I cut large balsa rectangles, glued them into place on the rear spar and then sanded them down to the airfoil shape using the wing ribs. Also a diagonal piece of 1/8" balsa was placed between W8 and W9 and sanded down to shape as well.


Then following some full-scale practices, a piece of 3/32" lite-ply was cut and glued to the inside edge of the rear spar where the Landing wires will be bolted to the rear spar:


Also a piece of 3/4" Tri-stock is glued where the aft spar butt-glues to rib W8 and sanded to shape, this strengthened this area up tremendously. In hind-sight, a 1/4" balsa gusset could of been used as well, but i'm planning for the wing sheeting to provide allot of strength as well.

Also, the 3/32" lite-ply shear webs were installed between the W2 and W3 ribs, and between the W5 and W6 ribs. their was also a 3/8" basswood block installed between the spars and shear-webs as well. This is for the forward landing wire attach bracket to bolt to.


Basswood filler block between the spars between ribs W5 and W6:


The horizontal stab and elevators were also sanded after glassing in prep for a coat of primer later on..

I did a quick mock-up to see the size.


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