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Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
thanks for the comments. I've learned so much on web sites, it's always nice to give a little bit back.
Main retract fairings (continued)
pic 1: Four screws have been put on each side of the fairings through the hard mounts previously installed. Note the piece of FG across the back of each fairing that will be removed in pic 3.
pic 2: The gussets are epoxied in the back of the fairing. These hold the fairing's shape after that temporary piece of FG is cut out.
pic 3: A horizontal piece of ply is epoxied to the gusset, then drilled and a screw put in to hold the back of the fairing to the wing. The piece of FG on the back of the fairing has been cut out (piece is on the left in the picture).
Posts: 1438
Joined: 2/2/2002 From: Lakeside, AZ, USA Status: offline
Sam your comming along real nice. The kit looks to be well enginered and the retracts look awsome. Does Yellow have the specs on the retracts? I have a scratch built Art Johnson P 40 with homemade retracts in it I would like to find some others that would fit. I need to borrow George, Then maybe I could get something done. Thanks Rich
Posts: 1669
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
Main retract fairings (continued).
pic 1: Parts needed: Nelson Hobby specialties: http://www.nelsonhobby.com/ piano hinge 1/2"X10" (I got three) part PH1210
Yellow aircraft: Offset hinge, need 3 pr, part A2201
Micro fasteners: http://www.microfasteners.com/ 1 SMFPK0003 Flat Head Sheet Meta $ 4.10 $ 4.10 1 SMFPS0206 Flat Head Sheet Meta $ 3.10 $ 3.10 these are #0 and #2 flat head screws
pic 2: Main door prep. The FG doors get 3/32" balsa sheeting inside the doors. Wet the balsa sheeting, bend and put tape around them and pop them into a microwave for several seconds on high to warm them up and dries them out.
pic 3: now with a 'fixed' bend in the balsa sheeting, they'll less likely to deform our curved FG doors.
pic 4: The front of my FG doors need about a 1/16" removed so they would properly lay in the fairings recess. I put tape around the FG doors to hold them and also checking that they are the correct curve by laying them on the fairings. I made the FG door a little bit tighter radius since materials tend to 'spring' out a small amount after the glue dries. A few clamps to hold the two parts together should do it. Except for the back of the door, there is a 1/4" reveal between the FG door and the balsa sheeting.
< Message edited by samparfitt -- 1/5/2007 3:15:57 PM >
Posts: 1669
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
Horizontal stab and elevator. (My #0 screws didn't come in for the retract doors so I moved onto the tail feathers)
pic 1/2: The horizontal stab is constructed the same as the wing: foam with sheeting and LE/TE already on. Again, I put some masking tape on the sheeting while I sanded the LE and TE. Then I masked off the outside ends and epoxied 1/64" ply. Note in the background, the gear doors on the fairings fit real good (well).
pic 3: The elevator is 'built up' but it is easy and quick. If you can read letters and numbers, you can handle this! All parts are labeled E-1 through E-14. The big parts aren't numbered but they are easy to figure out where they go. I put some saran wrap over the plans to protect them.
pic 4/5: There is a center balsa sheet that all the half ribs are CA'ed to. The half ribs have right triangles that goes towards the balsa sheet. The round holes in the balsa sheet is my doing: I used a forstner bit to lighten up the elevator. (On warbirds, every 2 ounces removed from the tail feathers probably saves a pound of weight up front)
pic 6: Both sides CA'ed to the center balsa sheet. ps: I love that CA, sure is quicker than that Pactra stuff back in the fifties!
< Message edited by samparfitt -- 1/5/2007 10:48:53 PM >
Posts: 1669
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
Horizontal stab and elevator (continued)
pic 1: LE of elevators epoxied on.
pic 2: Horizontal stabs end blocks epoxied on.
pic 3: Lots of blocks to be glued on. I'm concerned about two things.
1. Weight: I have tack CA'ed the inner and outer blocks on the elevator. I plan on sanding them to the contour of the elevator, then taking them off and hollowing them out. Same with the trim tabs on the elevator. The counter weights for the elevator can be rounded over and then hollowed out and then CA'ed onto the elevator. After sanding the outer blocks on the stab to match the stab contour, I should also be able to hollow those out.
2. Horizontal stab strength: I'm concerned about how strong the two halves will be with only foam core and 3/32" sheeting holding the two halves together. I'm considering drilling holes into each foam half and connecting the two halves with an 18" CF rod. It adds weight but it sure would make that stab seem a lot stronger at the center joint. Any thoughts on this would be appreciated!
< Message edited by samparfitt -- 1/6/2007 8:37:30 AM >
Posts: 1438
Joined: 2/2/2002 From: Lakeside, AZ, USA Status: offline
Sam I would think a 1/8 light ply brace would be more than enough. You may not even need that. It will get alot of sreenth from the fush also. Just my 2 cents. Rich
Posts: 1669
Joined: 9/1/2002 From: West Chester, OH, USA Status: offline
The fuse is about 2.5" wide where the stab is anchored. Also, glassing should strenghten it plus, I could put a few strips of heavy duty auto FG on that seem.
pic 1: I got the rudder parts out. Same build procedure as the elevator.
pic 2: Did a little detailing on the cockpit.
Horizontal stab and elevator (continued)
pic 3/4/5: Hollowed out the elevator's counter weight and the inner block. Also the trim tab and the outer tip were hollowed out. I used a forstner bit and then a dremel metal grinder.
pic 6: The outer tip of the stab. This was epoxied on so an X-acto knife cut near the epoxy and a little bending snapped it off. The clean brake will allow some CA to hold it on after hollowing it out. I also did the exposed area (on the right in the picture) but I can glass that over so it won't be seen.
pic 7: All pieces CA'ed back on.
pic 8: As with the wing, two triangular strips were CA'ed to the TE of the stab. There was a lot of sanding to get all those blocks flush with the stab and elevator. I used my detail sander to get the bulk of it down and then the sandpaper stick to finish up. One side down, one more to go!
Not sure how much all that hollowing will help but it won't hurt. Also, they are all non-stress areas so no structual integrity was compromised and, after glassing, it's unlikely that they will come off.
< Message edited by samparfitt -- 1/6/2007 7:34:04 PM >
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RE: Yellow P-40 build thread - 
