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Franny
09-25-2007, 04:08 AM
Hi All,

I just finished (mostly) Kurt's Military trainer and I thought I would share some photos. It really is a fun airplane to build and can host a wide range of detail. It is a big enough model to feel "substantial", but small enough to fin in my Beetle in one piece. I chose an AXI 2826 to spin the propeller and will be powering that with a 4000mAh 4S Lipo. I still need to get the speed control, BEC and RX, but we are just about to move and I needed to get this off the building board. I built it pretty closely the plans except for the horizontal and vertical stabilizers, to which I added a bit of thickness and sanded in a symmetrical airfoil. I also added a big battery hatch with six cooling holes for those 90+ deg flying days.

I’ll start with a few pictures I used for reference…

Franny

Franny
09-25-2007, 04:10 AM
I started on the top wing and worked down to the bottom wings. I have not built with the ply trailing edges or scale ribs, but it really works well. They are built from the outsides in creating a frame and then adding the interior parts. The wing tips are build as a unit and then attached. I built the top wing in on piece for a bit of added strength. Kurt has a great way of building in strut attachment points with metal landing gear straps. It works great and really helps with the alignment of all three wings.

Franny
09-25-2007, 04:13 AM
The bottom wing is built as two halves which actually attach to the fuselage sides instead of a one piece wing mounted on the bottom of the fuselage. This is really a neat way to go because of its scale appearance and because it leaves the center bay open and accessible with the bottom win halves attached. There are large alignment pins and the wings are attached with nylon bolts incase of a more “gymnastic” landing.

Franny
09-25-2007, 04:16 AM
For the tail feathers, I decided to add a little thickness to look a bit more scale and to, hopefully, improve low speed stalling. Not that it needs it, but I do prefer a symmetrical airfoil cross-section to a flat plate. I guess those diagrams from my engineering classes still haunt me a bit… Anyway, I also notched the trailing edge of the surfaces to add a little more strength. I built the frame first and then added “ribs” that were about 1/16” to tall top and bottom so I could sand them to contour later. After all the surfaces were complete, I hinged them and sanded them to get a symmetrical shape. Afterwards, I added the additional necessary pieces to attach the covering along the mated surfaces.

Franny
09-25-2007, 04:20 AM
The Fuselage construction was pretty straightforward following the plans and text. I did add some soft ply strips to strengthen the firewall a bit. This may not be necessary, but since these radial/rotary engine airplanes always turn out a bit tail heavy for me, I thought a little beefing up forward of the CG isn’t a bad idea. Additionally. I also wrapped the cabane mount boxed with floss and soaked them in thin CA to help in one of my less than stellar landings. For the landing gear fairings, I built the majority out of balsa and filled the rest in with that super light spackling. It sands well and is even a bit flexible. Bending the piano wire for the gear and cabanes is always fun. I learned really fast that and bends past about 45 degrees need to be heated first or the metal will begin to fail. With Kurt’s great outboard strut design and wing mounting, you can tell pretty quickly if you are off with your bends. I went ahead and made the bottom hatch a large as possible and cut six large holes for cooling.

Franny
09-25-2007, 04:24 AM
I'm not sure what I was thinking, but I opted for the nine cylinder radial. that meant I had to construct nine cylinders and the crankcase. That is well over 100 pieces right there! But, it all paid off because Kurt's design is great and you end up with a fabulous engine which also doubles as the AXI 2826 motor mount. Very slick. He even includs extra parts "just in case..."

Franny
09-25-2007, 04:28 AM
Here are some photos before covering. She is quite the looker.... Scale ribs and look at all those stringers!

Grasshopper
09-25-2007, 04:28 AM
Very nice work Franny.

Franny
09-25-2007, 04:29 AM
Thanks Tom!

firemanbill
09-25-2007, 04:29 AM
Yes indeed! Very Very Nice!

Franny
09-25-2007, 04:33 AM
I went with the gray fuselage just to be a little different. I love that blue rudder so I had to do that too. I added a little cockpit detail and a pair of windshields made from basswood and a clear plastic container. The wheels are Robarts and the prop is a Master Airscrew electric wood that is now discontinued. The covering is UltraCote. Great stuff! I used polished steel piano wire for the tail struts and stretchy fine shock cord for the flying rigging. Her final weight is 3.5 lbs minus the 12oz. battery. I can't wait to see her in the air!

I have a gazillon photos if you want to download them here => http://frannybrodigan.com/Smaller.zip
and I'd be happy to answer any questions or comments.

This is an Awesome kit!!! Highly recommended!!

Thanks!

Franny

Franny
09-25-2007, 04:34 AM
Thanks Bill!

I hope to get flight photos soon...

Franny

Grasshopper
09-25-2007, 04:35 AM
I guess I should have waited till the end to post. OMG Franny, that is beautiful. How big is it? What is the AUW? Details details please.

Franny
09-25-2007, 04:42 AM
Hi Tom,

It is 48" wing span and should be just under 4.5lbs. Not exactly a park flyer, but not too huge either... I haven't spun up the prop, but it should pull a solid 400-450W with that AXI2826. It has four servos and the wings are actually removable believe it or not. The Aerodrome RC kits are really nice and for a "short" kit you get the dummy engine, wheels, three rolled plans, and wheel kits! I didn't use the wheels because I found those Robarts and had to have them. I can't wait to see it in the air... I also think it would make a good two meter sailplane tow plane. Wouldn't it look cool pulling up a scale sailplane? It really was a fun kit to build. You can check out their site here => http://www.aerodromerc.com (http://www.aerodromerc.com/)

Franny

pd1
09-25-2007, 01:35 PM
Hi Franny,
The plane looks great. You did a wonderful job.

When are you testing it?
Did you have to add any weight to the front to balance?

Paul

19thsqn
09-25-2007, 05:49 PM
Fantastic woodwork and for sure beautiful plane!!

Jukka

Franny
09-25-2007, 06:12 PM
Thanks Paul and jukka,

Well, I haven't balanced it just yet, but I might have to a put a smidgen in front. The original has this super heavy hunk of steel mounted on the end of the firewall and when we build our models, we usually build that part out of light balsa. It always causes me grief! I hope to get it in the air before too long. We are moving across town so things are a little nutty now... But, I will be much closer to the airplane park!

I'll post flight pictures in a bit. Paul, I still have to maiden that Shoestring if you can believe that...

Franny

Gnascher
09-25-2007, 07:41 PM
I've been salivating over this kit. Unfortunately it's just a little to large for me. It's weight pushes it over the edge into more expensive equipment, and pinches me on places to fly.

If they ever release a 36" or so version of this model, I'm on it in a heartbeat.

You've done a stunning job on yours. I can't wait to see some video. You should submit your pictures to aerodromerc. They've only got one example of this model in their gallery.

Franny
09-25-2007, 08:32 PM
Thanks Gnascher,

I have submitted all of my documentation to Kurt. Sorry it is too big for you; thats a bummer. I have a mix of this size and the "400" size and I do fly the 400s more. They are much easier to transport and the equipment is easier to work with. That said, I really like this size best from a shear model stand point. I have a 400 size Dare Fokker DRI and it is fun to fly, but would do better if it was this size. My Little Gasser (.049 size) is great fun and so easy to fly and control. It depends on the model for me. Most of my larger ones are scale and the smaller ones are sport or vintage.

You might want to shoot Kurt an email... It can't be too hard to scale this guy down to, say, 36"?

Franny

Gnascher
09-25-2007, 08:47 PM
You might want to shoot Kurt an email... It can't be too hard to scale this guy down to, say, 36"?

Franny

I did try to go this route. He said that the way the plans are drawn wouldn't lend itself well to reduction using a copier or scanner and that it'd take him at least a week of work to resize the plans in his CAD software. He said it's possible that he'll release a scaled-down version but it wouldn't be for at least a year. So I wait.

If I should end up finding a flying site that I could confidently fly that model in then maybe. But even still that's an investment in pricier batteries, ESC and motor too. I wouldn't be able to utilize my existing collection of Lipos, etc... Keeping 'Wife Approval Factor' requires keeping my budget under control!

Franny
09-25-2007, 10:30 PM
I totally understand... I usually get a small bonus at the end of the year and I have to make that stretch throughout the entire year. It is all but gone now. So, now I build what I have and rely on my small allowance and leave them "Almost Ready to Fly" so to speak...

Franny

Sky Sharkster
09-26-2007, 01:35 AM
Hi Franny, Fantastic work on the Stearman! Wow, those glow flyers are going to go nuts when they see that baby!
Kurt should be pleased with your build, now we're all waiting for the flight report!
See you soon,
Ron

Franny
09-26-2007, 03:23 AM
Thanks Ron,

I won't fly it without you, buddy!

Franny

E-Challenged
09-26-2007, 09:46 PM
Looks very scale-like. I was wondering about the landing gear legs though. Are they "stiff legged" i.e. with no shock absorbing action. If so, I wonder if some sort of flexible joint near the fuselage could be formed with silicone or a flexible "cuff fairing" made with some of the thin flexible plastic stuff I bought at at craft store in the kid's craft section and used for the gear legs on Tritles' Cessna 140. I'm going to take a closer look at Kurt's kit.:)

Franny
09-26-2007, 10:14 PM
Hi E,

The gear is comprised of two bent piano wires; one forward and one aft a tad. I don't expect the gear to flex for and aft much, but maybe in and out a little. The wire size is 1/8", so pretty substantial. I am wondering about the fairing as well... Kurt called for blue foam or something similar. I opted for that super light flexible spackling which won't flex as much as the foam I bet. It seems pretty strong... The forward wire is attached to one of the formers and the rear wire is inserted into a copper tube blocked in and running the width of the fuse. Time will tell I suppose.

I think Kurt's are some of the most scale kits in this size range. Just the scale number of ribs makes a huge difference. He is a very meticulous designer.

Thanks,

Franny

Bill G
10-21-2007, 03:07 AM
Very clean work. :)
Way more pride in owning a handbuilt, than the ARF Stearman done in the same scheme.

I imagine that 2 wire "V" setup for the landing gear legs should be pretty strong. Much better than single wire leg.

haze_b
10-22-2007, 12:07 AM
Beautiful work!!!! How does she fly?

Franny
10-22-2007, 07:24 PM
Thanks Bill and haze,

I haven't flown it yet (in the middle of a move right now), but I bet, if I can get the balance right, it should fly well. It sure was fun to build! I still have one ARF (a little Wattage Stagerwing the LOVES to snap roll) and it hangs on the wall. The hand-builts do take a bunch of time, but I love sticking little bits of balsa together on a cold, bleak afternoon watching a favorite movie in my warm workroom.

My next project will be a Fokker DVIII from AerdromeRC. That should be super cool! I'll have to figure out how to do one of those crazy paint schemes!

Franny

Bill G
10-23-2007, 02:31 AM
BTW Franny,
I finally flew my Guillows DR1 and still have it in 1 piece!:D
(came to mind when I saw your avatar)

Should be much better now that I changed the elevator incidence.

Franny
10-23-2007, 06:18 PM
Hi Bill,

Ya know... I actually have a small bit of down elevator to get mine to fly level. I Imagine that could be a number of things, but it is interesting to fly something with sooo much lift! But, it does seem like it may be an incidence issue. Not much I can do about that... How are your landings? I bipped mine in on the last flight as it stalled just at the last second. It only bent the LG a tad, but I need to remember (as with the Stearman I bet too) to keep the airspeed up on landings!

Thanks for sharing! The DRI is my all-time favorite! My avitar is the Dare 31". Aerodrome now has a larger 46" DRI that I'm itchin' for. The power is the same as the Stearman - AXI 2826. That is about as big as I get... About .35-.46 size.

Franny

Bill G
10-24-2007, 04:15 AM
Hi Bill,

Ya know... I actually have a small bit of down elevator to get mine to fly level. I Imagine that could be a number of things, but it is interesting to fly something with sooo much lift! But, it does seem like it may be an incidence issue. Not much I can do about that... How are your landings? I bipped mine in on the last flight as it stalled just at the last second. It only bent the LG a tad, but I need to remember (as with the Stearman I bet too) to keep the airspeed up on landings!

Thanks for sharing! The DRI is my all-time favorite! My avitar is the Dare 31". Aerodrome now has a larger 46" DRI that I'm itchin' for. The power is the same as the Stearman - AXI 2826. That is about as big as I get... About .35-.46 size.

Franny

It slowed down real nicely at 6.5oz. There's a lot of wing there. That field (in my last pic) is really forgiving. I don't even think I'll join the club next year. I fly all small stuff, and that high grass is great. Too far drive to the club.
I pick the areas with the tallest grass and weeds for the first launch also.

I'm hoping that the 3/32" shim that I put under the front of the elevator should help a lot. I'd love to get this flying to the point where I could trust it to an indoor meet.

The first lauch, before I flew it with a lot of down elevator trim, went straight up and over. Fortunately and for the first time, I was able to try something that I've been wanting to do. Save a ground looper from damage by NOT:D trying to right it, and just flying it into the ground inverted. It worked fine, and no damage. I don't want to have to do that again though.:D

Yes, with all that lift I was surprised how little power it needed. I had a brushed IPS in it, but never flew with it, thinking it wouldn't be enough. It probably would have been fine. I installed a 5866kv Feigao in an IPS "A" gearbox. Has hover potential now.

Sharkykzn
10-31-2007, 04:46 PM
Hi Franny.

Thanks for the build thread, and well done on a fantastic job, you have sold me on this kit, as good Stearman kits are rare. I have been looking around for a while.

You appear to have used a conventional motor mount on your build, any idea how the Radial Mount Set for the AXI motor will work on the plane?

Also can't wait for your maiden flight report and a few pics to see her airborne.

Franny
10-31-2007, 07:23 PM
Hi Sharky,

One of the neat details about this kit is that the dummy engine is actualy the motor mount. It seems quite strong and I did soak it a bit with thin CA. The kit also comes with extra cylinder parts just in case of a less than stellar landing. You could use the "X" mount if you like and mount directly to the firewall, but I wanted to save the dough on the AXI conversion kit. Kurt has published an addendum to the kit plans from some suggestions I sent him. You can check that out here (big PDF file): http://www.aerodromerc.com/Goldenage/PT_Trainer_48/PTMilitaryTrainer_Notes.pdf

Good luck on yours! I really enjoyed the build!

I hope to get it in the air before too long.

Thanks,

Franny

E-Challenged
11-27-2007, 03:31 PM
It seems that most Stearman bipes tend to fly like yours and need the zooming and stalling/tip stalling tendency to be tamed. I had quite a hassle getting my Guillows PT-17 to fly before the lipo/brushless revolution. the various power sytems with NiMh packs weighed too much and had too little power for their weight. I read various opionions on wing incidence settings for bipes and finally set the top wing to around zero incidence and the bottom wing at one or two degrees per the plans. I built dihedral into both wings, no ailerons. I always had to fly with slight down-elevator trim even with slight nose heaviness. My successful power setup was a GWS DXA gearbox with a Medusa 12mm 4200KV motor and 400mah 3S ( 3-cell) lipo pack and 8x4 slow flier prop, noticeable down and right thrust. I had to make a slot in the firewall so that the lipo pack protruded into the ring cowl along side the motor gear/drive to get proper balance without exessive clay in the nose. I removed the plastic dummy radial and made a cowl ring out of an ABS calcium supplement container. Rudder and elevator were very sensitive so I reduced the throw. Once I got the overall weight down and incidences right it did nice ROG's, would loop without rolling out and flew predictably. Pat Tritle's Waco YMF is supposed to be a piece of cake to set up and fly.

Jollyroger
03-21-2008, 09:08 PM
I wondered when someone going to get around to building this one. Whenever I go to their website, I have to take another look at the Stearman.
Incidently, a couple years ago I took a ride in one. One of our clubmembers is a chater jet pilot whose boss owned a big black roaring Stearman. Built in 1943 and was based somewhere in Kansas during the war for primary flight training.
What A ride! better than anything at Cedar Point!

Franny
03-21-2008, 09:16 PM
They are like none other... Rent or buy a copy of "Dive Bomber" With Errol Flynn. Great flick and lots of Stearman footage. It was made at the beginning of WWII and is all Navy flying.

I hope to maiden this one soon. We are starting a basement re-model and that has most of my time right now. She is all ready to go and I expect great things!

Franny

Rabbitcreekok
03-21-2008, 10:12 PM
Another movie with a lot of Stearman flying is Gypsy Angels, if you can find the tape. They do a stunt where the Stearman flies under two cars jumping over ramps from opposite directions. Vanna White plays a reformed stripper. I guess this was before her letter turning days.

mountainflyer08
04-27-2008, 03:11 AM
Franny,
That is awesome, I just ordered aerodrome's Bristol Scout, can't wait for the kit to arrive.. cool to see someone else from Colorado in here..Happy flying

Franny
04-28-2008, 06:20 PM
Thanks Mountainflyer!

I am still to fly it. Lots going on at home with a move/basement finishing and lawn all happening... I'll give a complete report when I finally get to it.

Do you ever make it up to Denver/Arvada? I fly out at the Arvada Associated Modelers park: http://www.arvadamodelers.com/

The AerodromeRC kits are just the best. Good luck on your Scout!!

Franny

jofrost
05-10-2008, 12:27 AM
Franny ,

Your Stearman is absolutely beautiful . I wish you all the best on your maiden:)

I have the Dare Fokker DR1 also and sounds to be its characteristic to have down trim . Other than that it flies beautifully . Yours looks to be the same scheme that was on the box , which was how I was going to do mine but opted for Richthoffens scheme instead:rolleyes:

-John

Franny
05-10-2008, 03:23 PM
Thanks John,

I did purchased the larger DRI from AerodromeRC and plan to do it in the "Waldo Pepper" colors (yellow and black checker board). I hoping it will be a little easier to get on and off the ground. Alas, it is still in the box though... I'm in the middle of a complete basement build out and the new workshop is just a bunch of 2X4 studs at this point. As for the Stearman maiden, I will get to that in a bit too. Too much time went into that so I want to be sure the conditions are good. I'll report back after the deed is done...

Thanks,

Franny

griffin
05-20-2008, 10:30 PM
Hi Franny,
This is one of the most striking scale planes I have seen. Fantastic work all the way around!

I'm keeping an eye on this thread, hoping to see some in-flight pics!

Steve

PS I grew up in Arvada on 66th street and went to Peck Elementry in the early 70's!

Franny
05-20-2008, 11:47 PM
Thanks Steve!

30+mph winds foiled the maiden attempt last weekend :( Here is a photo of her with her ribbon...

Small world... We are in a new area just east of 93 and just south of Leyden Rd. The airplane park is just west of us. I can see it from the living room window!

Franny

Gimpster
06-18-2008, 04:39 AM
Hey Franny,

I am thinking of building one of these over this comming winter. It will be the first real all wood kit I have built, but I do have a hybrid wood/foam kit build under my belt. How diffacult would you say it is to build for some one not acustom to working with balsa?

And you get a chance to fly it yet?

Thanks

Gimpster

Franny
07-08-2008, 09:00 PM
Hi Gimpster,

I would rate this as an intermediate kit. Most of it is straightforward, but there are a few parts that may challenge you. It really is a beautiful kit. Download the two manuals on the AerodromeRC site.

I haven't flown it yet darn it! That basement build out and weather has kept me from getting to the field for the past six weeks or so. One of these quiet evenings though...

Thanks,

Franny

Gimpster
07-10-2008, 04:24 AM
Franny,

Lucky for me I belong to the same club as Gary Ritchie, who has built several of the kits from Aerodrome RC and been the prototype builder on at least one. So if I run in to any problems I have some great help avalable.

Gimpster

Franny
07-10-2008, 07:44 PM
Sounds great G... Good luck and let me know if I can answer any questions. And, as always... post some photos!

f

ohaussie
08-28-2008, 07:35 PM
Franny...
Just a beautiful airplane.. and that's comming from a heli guy too... You might just have convinced me to venture onto the dark side...

Franny
08-28-2008, 08:12 PM
"Very powerful the dark side is... For, once you start down the dark path, forever will it dominate your destiny... Consume you it will!"

I think the little guy was right...

Hey, welcome to Wattflyer! Great to have you. Let me know if I can answer any questions about the Aerodrome Stearman. Great kit!

Franny

yflint
11-13-2008, 06:24 PM
Hi Franny,
You made an exelent work on your scale.
I fly this model from Aerodromerc for more then a year without any problems.
I attached some pictures of my Stearman.
Wish you many happy landings.
Y. Flint

CHELLIE
11-14-2008, 06:46 AM
Hi Franny,
You made an exelent work on your scale.
I fly this model from Aerodromerc for more then a year without any problems.
I attached some pictures of my Stearman.
Wish you many happy landings.
Y. Flint


That looks Sweet Y. Flint, nice job, Take care, Chellie

CHELLIE
11-14-2008, 06:49 AM
Thanks Steve!

30+mph winds foiled the maiden attempt last weekend :( Here is a photo of her with her ribbon...

Small world... We are in a new area just east of 93 and just south of Leyden Rd. The airplane park is just west of us. I can see it from the living room window!

Franny

SWEET SWEET SWEET Plane Franny :ws: BTW where have you been hidding at ???? we all miss you, Take care, Chellie

mharris1111
01-08-2009, 12:25 AM
Y Flint,
I built the same plane, did you have any problem
with balance ? I used 2-2100 lipos, 1-1000 nmh
up front,Still needed too add some weight ?
What was your final weight ? Thanks Mike

yflint
01-11-2009, 10:21 AM
Y Flint,
I built the same plane, did you have any problem
with balance ? I used 2-2100 lipos, 1-1000 nmh
up front,Still needed too add some weight ?
What was your final weight ? Thanks Mike

The total weight (without the battery) is 1860 gr. The battery I use is 2 of 3S 2500 mAh having a weight of 430 gr, therefore the total weight is 2285 gr.
Due to the short nose of the model it is necessary to add weight in the nose. I added 150 gr (it is included in the 1860 gr).
In addition, I use a receiver battery of 1100 mAh in 120 gr' located on the inner side of the firewall.

Y. Flint

mharris1111
01-11-2009, 03:41 PM
I was begining to think, i was balancing it in wrong
place, Thanks for the reply
Mike

modbuilder
02-27-2010, 08:32 PM
Hi Gang -- This is basically a bump to keep Franny's Stearman build log fresh, 'cause I'm starting the same build, and I want to keep it alive and current. Franny graciously exchanged some email thoughts back several months ago, and I'm just now getting one of those " 'round to it's" . My ambition is to build the 48" aerodromeRC short kit pretty much as designed, but go to school on it and see what mods I might want to make for a 60"-er. I'm grievously pained with the 6 to 9 oz dead weight that Franny had to stick in the nose to get the CG right. I'm determined to either lighten up something behind the CG enough to eliminate the dead weight in the nose, or put in an oversized motor or battery or something to get some value added from the weight. Thinking about lots of things to lighten it up behind the CG, but am a rookie builder, so I'm reluctant to drift too far away from the design/build instructions. Anyway, here's a bump for Franny's Stearman. Franny, if you're out there, how 'bout some flying video? BTW -- really appreciate all the great photos during the build. Regards..... Bob R.