RCU Forums - View Single Post - Platt Zero Build Thread
View Single Post
Old 10-04-2011 | 07:37 PM
  #26  
[email protected]
My Feedback: (6)
 
Joined: Jun 2005
Posts: 90
Likes: 0
Received 1 Like on 1 Post
From: Bradenton, FL VA
Default RE: Platt Zero Build Thread

On to the wing...

I set up my adjustojig to build this wing... First problem... the wing is too wide for it if I built the ADM5 version. By doing the rounded tip A6M3, I could have fit it, but I am ornery... and wanted the A6M3, but not with a 6" solid balsa wing tip...

After studying things a bit, I realized it was possible to simply extend the 5/32" jig rods beyond the outer limit of the jig for the outside ribs. This seemed to work out OK. The second picture shows more clearly how the oustide ribs extend beyond the jig. With this setup, I sacrificed being able to completely invert the wing on the jig, but it worked out fine.

To do this, however, I had to figure out a way to support the center rib without the rods, so I glued on a jig that fit neatly into the adjusto jig's center slot. Looking back on this, I think it would have been smarter to get longer rods because at one point in the build, I realized that the center rib was slightly misalligned, which reguired some sawing a regluing, regrettably.

Dave's plan calls for building each half of the wing at a time on the plan using a piece of balsa to raise the trailing edges to the right washout height.

It tooka while to settle on where to drill the jig rod holes to allign things according to plan, and it also took awhile to figure out what dihidral to set up on the jig (forced me to recal some junior high geometry) since the hight at rib 11 on the plan is <u>the height above the plan plane to the bottom of the rib</u>. On the Adjustojig, I needed to figure the equivelent heights based on the "jig dowel points" which are not at the bottom of the rib... this confused me for a while... it took a couple extra days of thinking time to figure it out.

Picture 4 shows the ply/basla dihidral brace with the pencil marks I drew to maintain sanity...
Attached Thumbnails Click image for larger version

Name:	Gd94006.jpg
Views:	394
Size:	77.7 KB
ID:	1670124   Click image for larger version

Name:	Fa85146.jpg
Views:	306
Size:	80.0 KB
ID:	1670125   Click image for larger version

Name:	Xc78308.jpg
Views:	294
Size:	50.2 KB
ID:	1670126   Click image for larger version

Name:	Cw63701.jpg
Views:	286
Size:	76.7 KB
ID:	1670127   Click image for larger version

Name:	Db84737.jpg
Views:	277
Size:	70.4 KB
ID:	1670128   Click image for larger version

Name:	Tr50127.jpg
Views:	267
Size:	52.2 KB
ID:	1670129   Click image for larger version

Name:	Yt62083.jpg
Views:	276
Size:	65.3 KB
ID:	1670130