Posts: 217
Joined: 12/6/2001 From: Sedalia,
CO, USA Status: offline
Any one building a yellow P-38 I have a set of the Yellow p-38 aluminum spinners New in box that I would like to get rid of. e-mail aquaskiman@hotmail.com
Posts: 1866
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
Yo Bill, Just saw your question. Sorry to say I've still been busy working on my daughter's kitchen cabinets. pic 1/2/3/4: Had to enlarge the kitchen doorway first (old lattice and plaster), move electrical, new header, etc and I finally could start to put the cabinets in. After this is done, I've got to build some Christmas presents for the 'kids': more furniture! I'm figuring around the middle of December to start heavy on the Yellow P-38, P-40, AT-6 and Ziroli P-51B. (these 10 hr days of hard labor are killing me!)
The only thing I've done related to planes is buy JR's new 2.4 X9303.
< Message edited by samparfitt -- 11/2/2007 3:30:11 AM >
Posts: 162
Joined: 12/6/2001 From: CygnetTasmania, AUSTRALIA Status: offline
No doubt about you mate, you are a great Father. I will look forward to December when you start again. I have been gathering gear for mine. I have one of the old Burt Baker ones that I would like to start on next year sometime. Take care my friend.
Posts: 1866
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
pic 1/2/3/4: I did get all the cabinets in. Ripped off two layers of linoleum to get to the original wood floor. Still got to build the maple counter but that won't be until it's warm again. On to the good stuff: P-38's!
----------------------------------- Engine (cont)
pic 5: Got her on her back so I can work on the throttle and choke linkage.
pic 6: The retracts are both mounted toward the inside edge of the booms so there's room for the choke/throttle servos on the outside edges. I made a removable servo tray with the throttle servo forward and the choke servo behind and a little higher than the throttle servo so the linkages don't interfer with each other.
pic 7: The choke and throttle move vertically on the carb. We need to change vertical motion into horizontal motion so we can connect the linkages to the servos.
pic 8: First I mounted an 'L' bracket to the engine base plate (Zenoah G-38's).
pic 9: I'm using B&B's choke and throttle linkage to change the vertical motion to horizontal motion. I also used Sullivan #506 Gold-n-Rod to connect the servos to B&B linkage. I used #2X26 ball sockets for all connections. The ball socket is very close to the fire wall and the back end of the socket will not slide into the blue outer guide tubing so I used about a 4" piece of carbon fiber tubing to hold the blue tubing near the fire wall. The back end of the socket can slide in the CF tubing while the back part of the CF tubing holds the front end of the blue tubing in place.
pic 10: A dry fit of the parts.
< Message edited by samparfitt -- 2/24/2008 1:04:05 AM >
Posts: 1866
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
Engine (cont)
pic 1/2/3/4: I used a long (12" ) 1/8" bit to get the pilot holes in the fire wall and next former back for the guides to the servos. I could use a drill to get the fire wall hole the proper size but I had to use a dremel grinding bit to enlarge the hole on the inside former due to space limitations. All ball sockets and also bracket mountings were tapped and locktit used to insure parts don't vibrate loose. Tapping plastic is pretty quick and easy and the mounting plate and bracket are thin metal so that wasn't bad either. This is a dry fit (linkage not yet connected to carb).
pic 5: The yellow/blue linkage going to the throttle/choke servos. I'll be using 2X56 ball sockets on this end also. As with the Texan, I want to be able to throttle the choke in case the throttle servo ever goes 'south' on me while in the air.
pic 6: A view of the left boom where the throttle/choke servo are on the same side as the carb.
pic 7: Unfortunately, the space for the throttle/choke servo on right boom is opposite of the carb so I'll have to run an 'S' between the fire wall and the second former to reach the servos (which still need to be mounted).
pic 8/9: Anybody know if this is enough air flow in and out for the engine to keep cool? It would be nice not to have to put a hole in the bottom but I'm fearing that I'll need it!
< Message edited by samparfitt -- 2/24/2008 1:09:56 AM >
Posts: 1866
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
I must have been brain dead asking about cutting a hole in the bottom of the cowl: I need it anyway for the muffler exhaust! ------------------ Engine (con).
pic 1: I connected up the right engine linkage to the throttle/choke almost as a mirror image of the left side. Here's the parts for the throttle/choke servo tray. I used 1/4" ply and the tray is removable using #6 hex head screws.
pic 2: Tray assembled.
pic 3: I put some scotch tape on the edge of the servo tray so no epoxy gets to it and epoxied/clamped the two tray mounts to the underside of the gear mounting ply.
pic 4: I removed the servo tray and added the servos. I'm using hitec's HS-645's: definately overkill but I've had lower torque servos (plastic gears) strip and and an extra 15 bucks per servo is no big deal on a multi-thousand dollar plane!
pic 5: After putting the servo tray in, I realized that I need to lower the tray so the connecting rods are below the gas tanks. I didn't have to worry about this on the left tray since the connecting rods stay on one side of the boom. The right rods need to cross over to the other side thus be below the tank. I just put the servo tray below the servo tray mounts and this gave me enough room.
pic 6: To reduce the 'S' curve to a minimum, I drilled about a 15 degree angle into the fire wall for the CF rod. As with the left side, I used two short pieces of CF rod to allow the 2-56 ball/socket to not interfer with the fire wall.
pic 7: Right side linkage connected.
pic 8: Inside view of linkage rod. With the rod going through the fire wall at a 15 degree angle, there's not much of an 'S' shape (good).
pic 9: I need to get more 2X56 ball/sockets and then connect the other end of the rods to the servos.
pic 10. With gear in place.
pic 11: Here's the left side. All four servos (two in left boom and the two in the right boom) have their servo arms to the right eliminating any need for servo reversers. I just realized that I have each choke connected to each of the two receivers. I have the throttles connected to one receiver so I need to connect both chokes to the opposite receiver: this should allow me to control the chokes should the throttle/s servos or receiver go south (Let me know if you see any flaws in this logic).
< Message edited by samparfitt -- 2/25/2008 5:31:11 PM >
Posts: 1866
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
Inner flaps (cont)
pic 1: Parts used for the inner flaps. Dubro #557 white plastic horn brakets screwed onto the flap torque rods. The servo side gets two 4-40 ball/socket sets. One socket on the bottom of the servo arm and the other socket on the top. Last are two 4-40 clevises to connect to each plastic horn bracket. I wanted to use ball/socket instead of the clevises but no room to connect the socket to the bracket via a hex head bolt.
pic 2: The inside edge of each flap recess on the inner wing gets an enlarged hole to get the torque rod with attached horn bracket into the center wing.
pic 3: As with the Yellow Texan, I'm using Robart's pocket hinges so the flaps can be removed for painting and future work. (also still need to glass them).
pic 4: There's not much clearance between the top of the servo and the servo arm so I put the hex head bolt in from the bottom side.
pic 5: Set up complete. All dry fitted. As mentioned previously, I cut an access hatch in the bottom of the center wing so I can easily get to the flap set up. I'll probably have to re-inforce those flap torque arms with some balsa and fixed gear straps.
--------------- pic 6/7: My Bob Dively P-40 cockpit kit just came in. That should be about it for all the major items when I start on the Yellow P-40. Always nice to get all major parts before building in case something is no longer made or back ordered.
Posts: 1866
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
Inner flaps (cont)
pic 1: I used 0.5 oz cloth to glass the inner flaps. I did both sides at once: one side first and then overlapped the TE by a 1/2" and then the other side but not overlapping the TE.
pic 2: As with the Yellow Texan, I put auto axle grease in the set screws of the hinge pockets so the epoxy doesn't get on the set screws. The plastic past the socket mount was cut off so the hinges can seat farther into the pockets: along with cutting off some of the end of the hinge that goes into the pocket.
pic 3: I used epoxy and microballs to hold the pockets in place.
< Message edited by samparfitt -- 2/27/2008 1:46:14 AM >
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RE: Yellow P-38 build thread - 
