Fiberglass/foam fuselage
12-14-2003, 08:48 PM
#1
Senior Member
Thread Starter
My Feedback: (1)
Join Date: Mar 2003
Location: N.E. OREGON
Posts: 296
Likes: 0
Received 0 Likes
on
0 Posts
Fiberglass/foam fuselage
I'm considering building a 1/4 scale aerobatic plane. In another thread I've seen people recommending 8-10 total oz. of fiberglass layers for the fuselage for adequate strength.
What I want to know is can you lay up 4oz cloth for the outside layer and then insert a hollow "fuselage liner" of 2oz cloth and then spray in expanding eurathane foam to lock the two together. So you would have a 4oz outer skin, a 1-1.5" foam layer, and then a 2oz inside layer to mount your Rx, battery, and servo tray to. Do you think you could do this without any internal wood braces in the rear. I would of course have wood firewall, LG mount, wing mounts, etc.
I understand that the molds would have to be very rigid. I would let the excess foam expand out the wing saddle, firewall, canopy area, and tip of the tail.
What I want to know is can you lay up 4oz cloth for the outside layer and then insert a hollow "fuselage liner" of 2oz cloth and then spray in expanding eurathane foam to lock the two together. So you would have a 4oz outer skin, a 1-1.5" foam layer, and then a 2oz inside layer to mount your Rx, battery, and servo tray to. Do you think you could do this without any internal wood braces in the rear. I would of course have wood firewall, LG mount, wing mounts, etc.
I understand that the molds would have to be very rigid. I would let the excess foam expand out the wing saddle, firewall, canopy area, and tip of the tail.
12-14-2003, 10:13 PM
#2
Senior Member
Join Date: Sep 2003
Location: Oconomowoc ,
WI
Posts: 325
Likes: 0
Received 0 Likes
on
0 Posts
RE: Fiberglass/foam fuselage
Expanding urethane foam can reach surprisingly high levels of heat and pressure.
Not only would your external molds need to be strong enough to resist bulge distortion and being forced open, but your inner core laminate might experience crushing deformation.
Try foam filling some test laminates that duplicate the laminates and their enclosure before risking your actual fuselage tooling and first parts.
Not only would your external molds need to be strong enough to resist bulge distortion and being forced open, but your inner core laminate might experience crushing deformation.
Try foam filling some test laminates that duplicate the laminates and their enclosure before risking your actual fuselage tooling and first parts.
