Changed it according to the plans,has to be 20-22 % of wing span so 22% of 35 inches is 7.7inches which is exactly the length of my horizontal stab.

from my experience the Tail horizontal stab is still too small... just goodle pictures of aeromodels and it will throw up a thousand of them.  Sit back and compare your tail area with the pictures shown there.... I guess for a 35 in wingspan... you coyld easily have about a 15 in or more of tail horizontal stab span.  mine is about 16in for my 37 in trainer model.  

Whatever you make... today we have a tremendous advantage of checking everything with Google Baba or thr universal trainer called the Youtube.  just google in free plans for trainer aeromodel and you will find many which you can actually use.  I did the same for my models recently it flies really well..

Your fuselage and vertical stab still appear a bit shaky to me.... i.e. low on rigidity.  try this link.....

https://www.google.co.in/search?q=pictures+of+aeromodel+plans&tbm=isch&tbo=u&source=univ&sa=X&ei=jF89U46bDYiQrgfS_YHoBw&ved=0CCYQsAQ&biw=1600&bih=769

OR

https://www.google.co.in/search?q=trainer+aero+model+plans&source=lnms&tbm=isch&sa=X&ei=M2A9U8mIAcePrQfRyID4AQ&ved=0CAYQ_AUoAQ&biw=1600&bih=769

AND

http://www.hippocketaeronautics.com/hpa_plans/data/thumbnails/78/pilot_ace_20-h.jpg


happy building

Will do the necessary changes by tonight ie will change the horizontal as well as the vertical stab.
Thankyou for the advice,
Regards
Priyum

P.S - Could you post a picture of your trainer please?

please see my posts it is there...... the pictures are available there.....  ok here is the link....  This model is a 48 in wing span and has a tail horizontal stab of over 18 in...

http://www.rcindia.org/electric-planes/my-third-electric-model-a-established-trainer-model/msg176307/#msg176307

Thanks a ton sir and moreover I live in New Delhi so could you tell me from which shop in kirti nagar did you buy the HD thermacol from and what were its charges,length,local name of the foam etc please because bio foam Is getting expensive for me!

Shobit is right, for 35" WS the Horizontal slab should be around 15"x5" or any combination of the net area.
HD thermacole is available with false ceiling makers(the ones in theaters) for 60 rs a 2" sheet and it bends like EPO,
a quick search around the market will throw you with lot of options.

Ashok.P

Did change my horizontal stab to 15 inches and vertical stab too ,will post the pictures soon.

OK>.. the HD thermocol was purchased from the given address:-
Mr Umesh
Verma Tools and Traders
BE-390, Hari Nagar
New delhi.
 He holds thermocol from 3-5 kg per mtr cube to over 30 kg per mtr cube.  Guess anything above 25 kg per mtr cube will be fine.  I am using 36kg per mtr cube and it cost me some rs 4000/- + for the mtr cube.  Mind you even 1/4 th of a mtr cube is a hell lot of thermocol for manking models.... guess over 12 can be made in that of about 4 ft in span... smaller ones... many more

Best wishes to all....