A very cheap and durable material is vinyl sheets that is used for mking banners and hoardings...
Can this be used for covering the wings with a frame made of any wood...
What can be the frame made of if balsa is not available.( next best after bals available everywhere

As for the vinyl wrapping I don't know.
But you can use Japonica(Dhupi Pine) as a substitute for balsa. Check out my Schoolmaster build thread for some more info. It is a lot cheaper than balsa as well.

Is its weight comparable to that of balsa?

Yes.. It's marginally (slightly) heavier,but if used correctly the weight will not differ a lot. Some of us use japonica spars on our balsa models because it's a lot stiffer than balsa and a fair bit stronger.

As for your vinyl covering question this might answer it..
http://www.indiarc.com/monokote.htm

Thanks... I asked this because on the way to my college I find many vinyl hoardings printers and I can get this easily

What i suspect is that vinyl wont shrink (i may be wrong) and also is fairly heavier than normal covering so you should check it on a little test sample first before applying it on the model.

Alright... i haven't started making a model with it yet... I will first get some japonica and try on a sample piece of vinyl

Hey Topalle,
I have used vinyl covering and am still using it.  in fact today I purchased about 25 meters of it for covering my upcoing RC Gliders.... own built 1.7 and 2.5 mrt wing spans.  OK.. vinyl covering is slightly heavier than the rest.  BUT they also have it in many varieties i.e. some which are lighter and some which have a stiffer glue.  Generally the vinyl sheet glue tends to give way and it starts to peel off from the wood.  All you need to do is dope your wood wings well and sand them very smooth.  Next use a rubber solution Fevibond / bonfix) at places where you wish to stick the vinyl sheet (it is my way of double ensuring that the vinyl sheet sticks well to the wood).  cover the bottom half first with a piece of vinyl sheet and use a seperate sheet to cover the top half (overlap at the LE by about an inch.... do not forget to put the fevibond / bonfix at the joint).  Do not cover the entire wing in one sheet as it will get wrinkles or have errors which will show later....  Let it dry for a few hours or maybe the night.  Next day use your hot air blower to blow dry it.  It stretches really well....

Now you can make whatever design or colour combination you wish to make by another layer of vinyl sheet or radium sheet (this sheet is slightly brittle but lighter) or use can use coloured masking tape which is much lighter.  

I generally use a white or a light coloured vinyl sheet to cover my wing and then draw my designs with colourd tape.

Secondly you can also use the normal gift wrapping synthetic sheet for covering your model (use fevibond to stick the sheet- it cost just Rs 5 for a sheet).  it also stretches very well and is far lighter.  I generally paint this sheet with normal synthetic enamal paint (berger or asian paint .... use nitrocelluose thinner the one used by car painter on the road side as it mixes well with the enemal and dries off quickly instead of kerosine or terpentine oil.  Avoid usign kerosine or terpentine as thinners here).

The final thing............. I must have made over a 100 models till now.... never used monokote or anyother certified aeromodelling covering sheet.  Started using the venyl sheet just about a year ago as I am getting lazy now and do not wish to paint my model with enemal paint.... a 2-3 days job.  The first model (6 feet span RC glider) you see in my post is covered with the gift wrapping paper and painted by me using synthetic enemal paint.... so you see it works really well....  The second ( 5 feet span powered RC model) one has been covered with vinyl sheet (it belongs to Vivek Sharma).

Happy making your model and flying it....
Best wishes....

Topalle, am not sure what exactly you mean when you say vinyl, but I have used those colored plastic sheets that painters used to decorate glass, usually the windshield of trucks etc to cover my hot wired foam wings and they work pretty well, they are a bit tricky to stick to but at the end they don't add considerable weight. For reference, my foam plane having a wingspan of 48" and fuse length 32" weighted 185 after covering. Hope this helps

Regards
Bilal

Vinyl sheet? Go ahead use it, I am also fan of the same

@shobhit17 I guess you are confused about the vinyl. What topalle asked was the sticker based one used in sign boards etc. they don't use rubber based adhesives to stick it. 

Sorry ignore it, I skipped a line where you stated the glue isn't strong. Pls accept my apologies for the oversight

Ha ha ha..... Yashodha I can understand the error.  Be my guest... the post is long and hence one may tend to loose sight of a few lines.
I have an experience of over many many years as I started doing aeromodelling..... It was way back in 1980 when I made my first chyck glider and in 1982 made my first tow line glider (a 40" span glider).  So what ever I write here tends to have some genuine authenticity.  Further I made all my models from scrap wood and brought any Balsa or Japonica just once a while...... I generaly used home grown Balsa wood... it is now that I have shifted to foam wings as it saves me time......
Best wishes to you....
Happy Flying

I always struggle to find balsa. My friend has some indian balsa logs, but he doesn't know where to get them milled. Japonica is fairly readily available in Kolkata. As for Aurora Models, all their designs have been taken over by India's Hobby Centre (avoid at all costs). I got my Japonica from Mr. Irshad Anwar. He doesn't sell his japonica like that (even though he has tonnes of the stuff) but you may get it at some architectural model builder,they very often use japonica.

Thanks a lot Yashobhanp........

OK here is how to use the synthetic gift wrapping sheet to cover a wing.....

See the bottom line is that the entire wood has to be fuel proof and weather proof.  For that I paint the entire fuselage and tail with dope,  also the leading and the trailing edges of the wings including the centre section and the tips (basically the entire wood area).  Do about 2-3 thin layers on the wood and allow 15 - 30 minutes between the layers of dope.  Once dry use a 120 to 180 size sand paper to lightly sand the entire wood.  It will become very smooth and start to shine as if varnish finish has been given to it.  After this the balsa becomes stronger and doen not break easily.

Now buy the synthetic gift wrapping paper from any stationery shop.... cost aroud rs 5 per sheet.  take 4 sheets.  Put any rubber based solution on the trailing edge and leading edge of the underside of the wing.  Ask a friend to hold the sheet stretched along with you... hold from four corners.  Gently place it on the underside and cover it.  Cut out the extra sides.  Now do the same with the top of the wing.... keeping a margine of 1 inch on the LE and the TE.  Fold this to the bottom side and fix it with the rubber solution.  This will not be stretched tight but will be slightly loose or have wrinkles.  Let it dry overnight.

use a hot air gun to blow dry it.  I use a normal house hold iron (used for ironing clothes) to heat shrink it.  Have a lot of practice of this.  You might burn the paper if it is too hot.  Keep its temperature control at the middle and use it.  Some sheets require less temperature and sone need more.  Run the press on the entire covering sheet.  It will get stretched evenly.  Do a practice run on a dummer before using it on the model.  If it gets burnt.... use brown masking tape and heat shrink that also using the same press.

once this is complete you may paint the model with 2- 3 layers of enemal paint.  Paint on the synthetic sheet also.  See my glier it is painted and covered in a similar manner.

OK...... 
1.   Dope is Nitrocelluose based clear varnish.  Go to any paint shop and ask for it.  Normally you can also say Duko clear varnish.  It comes in .5 ltr tins or more.  Buy some Nirtocelluose thinner also called as air dry thinner or the thinner used by car paiters. Apply thin layers of paint.
2.   Rubber Based solution..... go to any stationery shop... ask for fevibond or Bonfix or such sulutions.  Even the gumming solution used by car tube puncture guys is the same... just sold by different brand names.

THE BOTTOM LINE IS.......... Once finished the model MUST look "HOT"