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Joined: 8/17/2002 From: n. canton,
OH, USA Status: offline
Well, after having this plane a couple years, I am finally getting started on it. I have given this a lot of thought and after vacillating back and forth over nitro or electric, I'm going with what I am most familiar with on this one. I will be installing two new Moki 61s with Pitts mufflers. The three biggest mods will be, the three piece wing, and rounding the bottom of the booms, and the retracts. So far, the wing is cut apart outside the booms and the center sections are joined together (pictured). They will be permanently attached to the booms and holes will be cut through the sheeting to access the compartments below. She will stay on her gear for transport, the way it should be. The way Nitro has this set up is totally stupid.
Here is a list of some of the mods I intend for her.
-three piece wing with carbon fiber wing tubes for the outboard sections -rounding off the bottom of the booms for a more scale look and to make more room for the wheels when retracted -adding retracts with scale looking struts and gear doors -adding cockpit detail to include a full body pilot with parachute and other gear, and interior detail -adding the missing canon to the nose -installing the counter balances to the elevator -installing the turbo scoops on the sides of the booms just under the trailing edges -adding some fairings to the center pod and wing attachment -adding the cross bracing to the canopy -possibly turning the flaps into the fowler type (not sure yet on this one) -detailing the appearance with Grey paint on the bottom, weathering, panel detail, simulated lights, polished ovals on the nocells, etc
The plane is exceptionally light to start with, so I think I can get this done and still have a lighter wing loading than most of these bigger war birds have. I'm finally mentally into this project and hope to see it through for a maiden this spring. The wing tubes were holding me up. I had the tubes but couldn't find the sleeves anywhere. A friend made me a pair out of glass, and now I'm off the drawing board and on the building table.
< Message edited by ram3500-RCU -- 2/20/2008 8:00:44 PM >
Posts: 1670
Joined: 8/17/2002 From: n. canton,
OH, USA Status: offline
I did the math on the tires and we need 5" mains and 3 7/8 " nose tires. I think I will cheat the mains down to 4 3/4" but that will still be a lot of tire to conceal. The booms aren't deep enough. I wish they had just rounded them to begin with. They did fine on the top. I don't see what the big deal was on the bottom.
Anyway. I get my sleeves and CF tubes back tomorrow, then I will set up the location. I'm leaning toward just behind the main spar. It will mean removing some of the rib material. I will take plenty of pictures.
< Message edited by ram3500-RCU -- 1/16/2008 8:54:51 PM >
Posts: 1670
Joined: 8/17/2002 From: n. canton,
OH, USA Status: offline
Made some more progress on the wing sections. Here are the fiberglass sleeves that a friend made for me. I chose 3/4" OD carbon fiber tubes and am laying it in just behind the main spar.
I made a fixture, out of a piece of brass I had on hand, to hold a step bit for reaching into the wings to drill out the ribs just behind the spar. I used CA to glue the bit in the end of the tube, then slid another piece of smaller diameter aluminum in the other end to keep the chuck from crushing it. Works great.
I tried a very sharp spade bit on the first hole, but it was too rough on the rib, as you can see. The step bit does a great job without cracking the ribs. A 13/16 hole saw would work also if you had an extension for it. I didn't have that tool on hand.
I am gluing the first sections in the outboard wings with Guerrilla glue and when dry, I will install the wing tubes, slide the inboard sleeves and the tubes into the center section, line it all up and then glue the center sleeves in place. I capped the inside end of the sleeves with balsa and CA to prevent any glue from getting in the end as I glued them in the wings. In the center, I went in as far as the back stop for the factory tube. In the outboard sections, I went three bays.
I have made light ply end plates to cap the exposed ends. I plan to use 1/4 X 20 nylon wing bolts and blind nuts to secure the outer sections. These I will access through the gear doors for the retracts. My intension is for the wing to boom, and turbo cover to top, all to be permanent attachments. Everything will be accessed via the gear bay, including servos.
< Message edited by ram3500-RCU -- 1/21/2008 6:32:18 AM >
Posts: 1670
Joined: 8/17/2002 From: n. canton,
OH, USA Status: offline
Never done this before (on an ARF), but so far, it seems to be going well. I now have the Port side outer panel tube and sleeves in place and glued up. I used Gorilla glue on the inboard section as well, since it worked so well on the other panels and it gives you plenty of time to get everybody lined up. An aluminum wing tube is stretch wrapped (this stays tight where as tape stretches and gets loose) in place to keep the panels straight. Tonight, the other side, then I can start to work on the end plates.
< Message edited by ram3500-RCU -- 1/21/2008 6:42:31 PM >
Posts: 1670
Joined: 8/17/2002 From: n. canton,
OH, USA Status: offline
More progress on my wing separation. I made plates and plywood inserts (3/16 ply) for the 1/4-20 blind nuts in the outboard sections. These have been glued in place. I first taped around the wing with 2" blue tape. After the epoxy dried, I could sand this flush without damaging the covering. Then I remove the tape and you can see the results. The flap servo was relocated and ply backer added it the new location before the end cap was glued on. I will now drill a small hole for the servo leads and that just leaves the installation of anti-rotation pins. These will be CF rod (male) in the outboard panel, and an aluminum tube (female) in the root.
Posts: 1670
Joined: 8/17/2002 From: n. canton,
OH, USA Status: offline
Couple more pictures of the process. As the boom is going to become a permanent part of the center section and add strength to the structure, I will cut the bottom skin away where the gear bay will be to access the new wing bolt (a metal 1/4-20) for the outer panel.
< Message edited by ram3500-RCU -- 1/25/2008 4:53:00 AM >
Posts: 1670
Joined: 8/17/2002 From: n. canton,
OH, USA Status: offline
Back to those booms. I gutted them of gear and servo mounting structures, and the OEM 2-56 push rod sleeves, and went to work on installing 'Precision Nyrod' tubes down the sides for tire clearance, and rounding the bottoms.
I am building in the gear doors and will cut them free after the sheeting is done. Double formers are where they will be cut out. They are within 1/2 " of being scale length. I made them long enough to mount the rudder and elevator servos just behind the tire, when retracted, if need be, for balance.
The wing cover may still need to be removable as I don't think I will be able to reach the wing bolt from the gear bay as I had hoped. If this is the case, I may just go back to mounting the servos up on top the wing and under this cover. Hook up and service would be easier anyway.
Posts: 1670
Joined: 8/17/2002 From: n. canton,
OH, USA Status: offline
Here you can see the new sleeves (crossed at the back to avoid the sharp bend), some of the former work in the front and for the gear bay, the Robart main gear I selected with it's 1/2" 'Robo Strut', and some of the stringer work.
< Message edited by ram3500-RCU -- 1/31/2008 4:26:09 AM >
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Nitro Models 90" P-38 (1/7 scale) with 3 piece win... - 
