Covering order prep

I'm pretty sold on Oratex at this point.  The process is essentially like covering a model airplane and there is no painting (and associated spray equipment) required.  So all I need is the covering, glue, tapes, and rib-stitching stuff.

How much covering is the big question to answer.  A standard Oratex roll is 71 inches wide (or 34.5 in, but that seems less practical) and cut to length by the meter.  Measuring out the components yields the cut-list:

• Wing bottom: 48 x 228 in (2x)
• Wing top: 54 x 228 in (2x)
• Aileron: 15 x 122 in (4x)
• Flap: 15 x 94 in (4x)
• Rudder: 28 x 48 in (2x)
• Stab, Elev: 40 x 100 in (2x)
• Vertical: 36 x 88 in (1x split into two triangles)
• Nose: 40 x 78 in (1x)
• Cabane: 24 x 52 in (4x) and 24 x 20 in (2x)

I originally had the aileron and flap as one-piece, instead of top/bottom, but this way will fit a wing top/bottom and an aileron/flap top/bottom in the 71 in of the roll.

I drew up a roll in CAD and tried to fit the cut list on top of it, tetris-style.  What came out was a total of 33m to cover all the pieces with 2" edge distance between parts.  It's 82400 in2 onto 92244 in2 of covering for a utilization factor of 89%.  The extra will likely be useful in lieu of anti-chafe tape.  For reference, that 10% overage is worth about $350 in 2014 prices, so it was worth the hour of CAD time.  I'll round up to 34m to be safe.

The price list I have from betteraircraftfabric.com is from Feb 2014, listing $109.95/m.  With the US Dollar strong against the Euro for the past year and a half, there is no reason for 2014 prices anymore, aside from whatever stock the distributor purchased at old prices.  The other option is TLAC in the UK (the Pound is really down against the Dollar right now after the Brexit vote), and their online price list is from May 2013.  Oil is also down 50% over the 2014 time period, so everything points to this being less expensive than it appears on paper.

For the adhesive, I read on another Oratex covering blog (here's another good one) that 1 gallon of adhesive matched up to 36 yd of fabric, so it's probably about the same for me.  It only comes in 1L or 5L increments, so I'll probably buy 3L and get more if I run out.

• 34m ($109.95/m) Oratex UL600 ($3738.30 from Feb 2014 price list)
• 10m (1 roll, $39.95) rib-lacing cord, colored-matched ... or 500 yd white for $45 from Aircraft Spruce
• 25m x 25mm (1 roll, $89.95) straight-edged tape, color-matched
• 3L ($61.95/L) hotmelt adhesive ($185.85)
• 7 x 10cm felt blade ($11.95)
• 2m release paper ($4.95)
• Total: $3986

The 82400 in2 also should give a clue of covering weight.  82400 in2 is about 53 m2, and at roughly 100 g/m2 for the covering, gives 5.3 kg (11.7 lb) of fabric.  Last time I weighed Goat, it was right at 100lb, so still well within the 154 lb Part 103 limit.  Adhesive will certainly add some more, and I haven't re-weighed after adding the 4lb seat, but it's still well within the ballpark.

Workin' at it.  What am I missing?