Hi again, Does anyone knwo where i could find foam the kind that you use to build planes with and is it a good idea to build a large scale model out of foam ic heard its really strong cheap and easy to work with it soun ds perfect for what i need it for.

Cheers
Josh

Worth a look

http://www.corpcomp.com/weeks1/DC10.htm

Don't forget that foam is ONLY to form the shape for you. Structurally it's not worth a damn. It will hold a shape, but spars, outer skin, hardpoints for mounting etc are all up to you. Without those items it's not worth the money you spend on it. There have been many large scale models made mostly of foam, byron originals had a couple planes that were almost totally foam, except for those structural parts. When using foam in a jet though, if it's turbine (and since you're mentioning large scale I'm assuming turbine) don't forget that the heat from the engine will melt it if used in the wrong places, and the foam will melt when in contact with turbine oil. So in short, if you want to use foam for basic shape that's fine, it's been used primarily for wing cores for years and years, but don't forget that foam all by itself is nowhere near strong enough.

Thats the kinda thing im looking for but it still doesnt mention anything about buying foam

You can buy foam at most hardware stores, the blue insulation foam works great, if you want to use the beaded white foam, hobby stores are a good place to look though you'll spend more money.

Yea but i thgouht about the turbines melting the wings but i was going to use some fireproofing round that area and also fiber glass the whole of the plane wit ha thin layer to strengthen it.

Let me guess, is this going to be your first jet and you're trying to do it on a budget? I'm not saying that to sound like an ass, I'm saying it because if so then you're probably going to be spending a lot of money on something that will be dangerous.

Just using a layer of fiberglass over foam isn't going to cut it, not unless you use the right weight of cloth etc. It's much easier to sheet it with balsa first, then glass it if you want. But most important is going to be adding the correct structure. The goal of all model airplanes is adequate strength without a huge amount of weight. Just using foam with some fiberglass around it isn't going to do what you need. "Fireproofing" the area's where the turbine will sit doesn't mean anything. So you might put something there that won't burn, big deal, what will the structure be where the engine will mount, what is the structure in the area that will get hot? If all you do is put a piece of stainless steel over the foam structure so it doesn't light on fire, it's going to melt all the foam out and you'll end up with nothing left in there anyway.

If you give us a better idea of what it is you are trying to accomplish, perhaps we can give you some better idea's on how to accomplish it safely.

Baisicaly what im trying to do is build a very good looking 767 - 200 or 300 with 2 artes falcon jets or something along them lines i want to haveenough power so if say the planes 30 pounds i want to have at least 10 pounds of thrust or something like that even 5 but i was thinking of making the engine "pods" out of fiber glass

Appreciate the help [sm=regular_smile.gif]

Hi,
Sheffield Insulations are where I buy my foam, they do all kinds , would suggest the fine grain white, I've not done a fuselage but have cut plenty of wings. Try this link

http://www.sheffins.co.uk/

Mike

Is it strong enough to make fusealage out of ?

How much building and flying experience do you have?

Do you realise how huge a project this is likely to be?

You need to work out, accurately, how much it is likely to weigh. If it is above 20 Kgs you will need CAA exemption to fly it and it will need to be inspected.

Have a look at the rules here http://www.caa.co.uk/docs/33/CAP658.PDF

Umm well iv only built the few ARTF's but i build other things don't kjnow whether thats the same as building a plane however i have a bit of flying experience iv been flying for about 3 years passed my A after about 3 months and have been flying aerobatics planes from then on.

Josh

Talk to Barry at Mainly Models Hitchin.

Buy a foam kit from him and build that. [The Hurricane flys well.]

He also sells a blue foam/paper Lancaster about 9 foot span that flys fine and does not come apart.

Brown Paper with judicious use of glass cloth reinforcement will give enough strength.

There are people around who build good stand off scale models going the route you are thinking about. IMHO it should work.

Josh,

Not to be discouraging, but before you tackle a project such as scratch building an Airliner of any sort, your modeling skills need to be at their best. That's not to say you can't do it, some people just have natural talent....but most don't when it comes to true scratch building, especially in a project of this magnitude.

Here is an excellent thread on Airliners if you have a couple hours of reading time to spare.

http://www.rcuniverse.com/forum/m_51...rliners/tm.htm