r ward

has anyone built a SPAD LC40 trainer and have come out anywhere near the advertised 5lbs.-10 oz. ? I built one and have nothing more on it than what the plans call for other than a MagnumXLS.46, rather than a .40 of any brand and it came out after balancing weighing 6lbs.-5oz.. does the weight of coroplast vary that much ?.

Tom Nied

I cant answer your question exactly, but if you are within 11 ounces as you describe and you are using a Magnum XLS .46, you are going to be ok. I'm sure weights of coro can differ from one manufacturer to another, but your not that far off that I wouldn't worry about it. Just make sure you COG is within spec.

r ward

belated thanks for that. I couldn't find any 2mm. corro for the wing locally, so I used what Home depot had. read that many people did the same thing with no bad reports,. I was just a bit puzzled over the all up weight issue with that .46 in front. to be honest given the area of the wing, I doubt the published weight was true even if 2mm. was used for the wing, as stated in the article.
as a side,....I don't think I've ever built a plane that came close to what the article's published weight is........

Clean

Was going to ask if you had a RNAF wing, 2 mil top, 4 mil bottom. Found your weight gain. It won't float as well as the original but you can always dial the ailerons into flaperons, bout 5-10 degrees will do. Hard to get 2 mil here in the mid states now, you can have it shipped in but the cost is absorbent.

r ward

yeah, there's no 2 millimeter anywhere around here either. I've been to every sign shop in the area within about 25 miles looking for some , too. I found one sign shop that will get some for me,..... if I order 25 sheets.
the plans spec'd 2mil. for entire wing, i'm pretty sure. I wasn't really worried about the added weight, just wondered about the issue of using 4mil. instead of 2 mil. for a wing after the wing was built, it had that " well,... it feels a bit heavy but it should be ok", feeling,.... if you know what I mean. not as light as it should be, but not really heavy feeling.
it flies fine.........

Adui

Ward; WHEN I was building and flying I almost always just used 4 mil corro for the wing. Only had one ever have a problem, and since it floated nicely I'm not calling that weight, more like under-powered. (Also it had a twisted wing so it flew.. interestingly..)

r ward

figured the added weight wouldn't be a problem,...just putting out there for reassurance. thanks for the comment. my first impression of the finished wing was,.." well, it feels a bit on the heavy side for it's size, but not so much that it will be a problem." then the next time I handles it , it seemed OK for it being a coro wing. it would be nice to be able to build it with 2 mm. I guess i'd like to see/feel physically, what the difference would be. I had no doubts that it will fly, OK.

Tom Nied

I've been struggling with the 2mm coro problem also. Hard to find, and when you do, its too expensive for the project. Considered just using 4mm, but don't like the added weight, especially when on some of the plans they say performance will be affected. Foam board from the dollar store might be a solution, but would need some kind of fuel proofing like EconoKote.

Adui

Would foam board be strong enough? I've considered it as well, but when I was flying a lot I tended to push the envelope on my air frames. I like to make them dance!

Tom Nied

Well, I'm thinking .15 size as in the Friday Night Special. But it would be worth experimenting. I've got a great little Magnum .15 that I had on a Gnat, but would like something like the Friday Night Special. I just want something I can start and throw into the air even on windy days.

Tom Nied

Another thing that could be done, is strip off a side of the 4mm to reduce weight. That might save enough weight for a wing that requires 2mm. What do you think?

ETpilot

Tom Nied

Ah, what I said earlier is crazy thinking. Remember what S.P.A.D.S. are suppose to be. SIMPLE. I've assessed what I've got, and I'm going to hack something together using the 4mm that I have. Don't over think this, keep it simple. The easier the better. I'm starting with a Dynamo wing. Engine is going to be an old OS Max 35, or a TT GP42. Would love to get the old OS Max 3 flying again. What the heck, we're suppose to be experimenting

Adui

THAT is the spirit of SPAD!!! Build it, Fly it! If it crashes build another!! (Or as is most likely, put a new prop on and fly it again!!)

Tom Nied

ETpilot

Tom Nied

Wing almost looks ok?

ETpilot

johnnymax

I am thinking a solution for going from 2mm to 4mm would be to take any plan for a plane that calls for 2mm coro, and double the size of the plane. Of course you would need more power. I am not trying to be funny. I think it makes sense. SPAD×2

Tom Nied

I get what you're saying. You're trying to reduce the wing-loading, right? I don't think you need to go all the way 2x, but use LAR, (looks about right) and see what happens. More power will ultimately make sense. I'm trying an old .35 OS Max on a .25 design. I'm not too worried about it if it flys ok. I will not be flying any combat. I just want something I can throw into the air and have fun with.

lecrote

My Feedback: (1)

you can follow here
http://spadworld.net/forum/viewtopic...288&highlight=

Tom Nied

Interesting problem. Looked at that and replied. I don't see any Spads at my field, so I'm weirdo. Keep experimenting for sure.

aspeed

I am glad I got a few sheets of 2mm a few years ago for $14 a sheet. The company never has any in stock and is quite hard to deal with. Unfortunately they are the main supplier for the whole country, it seems. I just junked a small heavy 4mm winged combat plane with a .40. It flew fairly well but needed to have a bit of power. It would fall out of the air at about 1/4 throttle but was fine at 1/3. It was quite fast at full throttle. It felt like a brick when carrying it around. Don't forget that a SPAD by definition allows for foam with tape or ____kote covering. That could be 1/4" foam sheets or hotwire cut foam. I have some blue fanfold 1/4" and blue 1/2" that I have some silly ideas for. Maybe a flat foamy Extra with a .40? Some pics here The blue and white 4mm wing before it's demise, 1/2" foam delta with an .09, And 4mm Gnat wings are an option too.


Gnat



I retired this one. A bit flexy but ok really.

lecrote

My Feedback: (1)

I just post some wing construction test

All wing are around 12inch span 8.5 chord without aileron
ribs are 3d print but can be done in coro.
4mm with ribs (flute spanwise)= 140gr



4mm bottom with 4mm strip on top covered with sign vinyl= 103gr


4mm with strip on top and bottom and covered with sign vinyl = 87gr


4mm slited in half = 84gr


Normal 2mm wing 10 7/8 inch=74gr so 12 inch= 82gr


so for the ease of building and weight the 2mm wing is the best choice.
Without 2mm on hand the 4mm strip wing covered with sign vinyl is the lighter one and the easier/faster to do.

I got another idea for the 4mm rib to remove some weight stay tuned.

Dan

Tom Nied

aspeed, what kind battery pack are you using for the SPAD with the landing gear?