850.....not sure.....
Frank, great to hear another -4 starting but I am a bit concerned you are setting a goal that you cant achieve. Sorry don't want to spoil the party, but I would hate to think of you disappointed, chasing your tail!
My -4 with oil in the engine weighs in at
975.6. I was conscious about weight throughout the build, but unless you got pounds wrong like the gallons when you adopted Imperial measurement I think it will be extraordinarily hard to achieve unless you throw structure away.
Yes I have an MT 2 blade so if you threw that out plus the governor, I am not sure, but since you will need a prop perhaps a saving of 20.6? If you hand swing it, the starter and wire perhaps 11 lbs. That takes you to 944. I have a True track and two servos. At a guess 10lbs so that is 934. Say 4 lbs of wire, so 930.
What does an altenator and associated wire plus an Odyssey, another 20? So 910.
Simpler instruments than mine, maybe 3 more, so 907, and smaller tyres, I know the answer here, 2.5 lbs, so 904.5. The back seat and upholstery, say 3.5, now we are at 901. Now I know you are going to throw a part of the wing away, but I cant believe that will be anything like 51lbs worth. I have just thought of one more 'extra' I have and that is thicker grade emp skins, say 3lbs so that is now 48lbs you are looking for. Yes there are a lot of estimates on my part. I hope I have been conservative but you might want to run the sums. My blog - link below - will show you what's in mine. One thing you wont see was that it was sprayed with ACF-50 a couple of days before weighing, perhaps another 2lbs, (I doubt it!) but that still leaves 46 to go.
I hope I am wrong. Good luck!
PS I would also run the sums on where the CofG will end up. Mine is at 68.03. Nearly everything I have chucked out in this post is forward. If the pilot also moves aft it is worth checking I think.
