Foam:
EPP - 1.3, 1.9 - Expanded Polypropylene - springy and forgiving, can use 3M Super 77 and 99 sprays with acetone
EPS - 1.8, Extruded Polystyrene - blue - usually poor quality - Can't use 77 or 99. 78 is made for this foam though.
EPS - 1.8, 2.0, 2.3 - Extruded Polystyrene - pink - ok quality
EPS - 1.0, 1.5, 2.0 lbs/ft^3 - Expanded Polystyrene - white - fine to use, relatively soft
Templates:
.020 aluminum, “vertical grade” (thin) Formica, light/thin plywood, fiberglass sheet (the one used for roofing, 1/16 thick), circuit board material, thick poster board, 1/32 phenolic sheet.
Sand edges to 400 grit - very smooth so wire glides.
Use aluminum on the smaller end to absorb heat and help you go slower on that end.
Maintain alignment holes. Secure with drywall screws into the foam.
Wire:
.012 flying line (fishing leader - braided stainless, melt off the coating)
up to .018 or .020 music wire
Nichrome doesn't work great, stretches a lot, tension is finicky before it breaks.
Typical kerf _____
Design Features:
Full length holes cut with wire for spar to be inserted and glued
Full length hole or slit for antenna wire
Slit for servo wires
Servo Pockets:
Cut out openings from the bottom.
Secure with hotglue (double stick foam tape?)
Servo installation:
Masking tape around the servo. Then clean with alcohol. Then use CA glue to hold the servo in the pocket. Can be removed later without permanently damaging the servo case.
Spar:
Carbon tube (bond with Gorilla Glue, Elmer's PVA, hot glue)
Carbon tow inserted vertically (as shear web) in a slit cut along the length of the wing (epoxy)
Carbon tow strip on top and bottom (epoxy)
Fillers:
Epoxy and microballoons
Epoxy and foam dust
Lightweight spackle doesn't stick very well and is really soft
Root Reinforcement:
1/8 plywood + 5 minute epoxy
Cap Strips Sides Adjacent to control surface cutouts (trailing edge reinforcement):
1/8 balsa + 5 minute epoxy
Control Surfaces:
Tapered balsa stock covered with Monokote
Robart hinges
Foam + fiberglass
>Quality metal hardware. No metal-on-metal connections to cause RF interference.
Covering:
Fiberglass patching mesh + spray glue + lots of weights to hold wing in proper shape in the wing beds
>Use wax paper (or release film) to keep from stick to wing beds while curing
Strapping tape + spray glue
Partial or full fiberglass ______ weight + epoxy + vacuum bag
Monokote - higher temp (***Need some tips on covering. Probably should spray a thin layer of adhesive on the surface before covering to help the covering stick to the wing. Secure at the edges with an iron, then heat gun for the middle areas.)
Econokote - lower temp
Ultracote
Doculam from Staples - lower temp
Wing Tips:
Motor, adapter, prop:
***Need to know max prop diameter with landing gear, then determine # of blades, pitch, and speed for motor.***
100W/lb, 5 lb -> 500 W (150 for 3D, 200 for crazy 3D)
12V nominal, 42 Amps
Thrust to weight ratio:
1lb/3lbs = 0.33 basic flying
1.5lb/3lbs = 0.5 advanced flying
1.71lb/3lbs = 0.57 aggressive flying
Use motor/prop calculator: http://brantuas.com/ezcalc/dma1.asp or http://www.drivecalc.de/ or
REFERENCES: