RCU Forums - View Single Post - 1/4 Scale Pfalz DrI
View Single Post
Old 01-02-2012, 05:56 AM
  #14  
Sethhunter
 
Join Date: Jun 2005
Location: Princeton Junction, NJ
Posts: 573
Likes: 0
Received 0 Likes on 0 Posts
Default RE: 1/4 Scale Pfalz DrI

Happy New Year! It's been a good time for building. Here's a few pictures of the fuselage coming together.
I built the round fuselage in two halves starting with a ply box, then balsa stringers, and finally diagonal balsa sheeting.
One of the more tricky bits is the joint between the fuselage and the bottom wing. Only the front third intersects the fuselage, so the box
offers only a partial saddle for the wing. We'll see in a later post how I extended support for the aft section of the wing, after the halves were joined.
The fuselage will have 3 hatches; one on top between the cabane struts (access fuel tank, receivers, batteries), on the bottom behind the firewall (access ignition and EIS battery, servos), and where the bottom wing comes off (access bolts for middle wing). I like diagonal strips for sheeting because it requires less fitting, and the arched grain seems to provide more strength. On the downside, when used to make halves, each half tends to spring-back a little when removed from the board (in my case, about 1/4" each). It's pretty easy to pull them back together when the halves are joined. The top and bottom longerons are 3/8 sq balsa on each half, or 3/8 x 3/4 when the halves are glued together.

The first picture shows the "half" firewalls being glued to the plywood sides with big hardwood gussets. After the glue cured, I drilled and doweled both the sides and firewall to the gussets. I used a tenoning jig on a tablesaw to hold a hardwood board at 45 degrees, then cross-cut the 45, flipped and cut again, to make an accurate triangular gusset where the grain runs parallel to the long side for max strength.
Attached Thumbnails Click image for larger version

Name:	Gd93987.jpg
Views:	30
Size:	45.6 KB
ID:	1708454   Click image for larger version

Name:	Fa85654.jpg
Views:	27
Size:	46.0 KB
ID:	1708455   Click image for larger version

Name:	Vb74035.jpg
Views:	32
Size:	42.8 KB
ID:	1708456   Click image for larger version

Name:	Ic83480.jpg
Views:	26
Size:	49.6 KB
ID:	1708457   Click image for larger version

Name:	Ju11807.jpg
Views:	25
Size:	50.9 KB
ID:	1708458   Click image for larger version

Name:	Br11948.jpg
Views:	30
Size:	39.4 KB
ID:	1708459   Click image for larger version

Name:	Ac64797.jpg
Views:	31
Size:	40.7 KB
ID:	1708460