Thanks guys. Beb- i used contest grade 3/32 from balsacabin, i think they class anything under 21g as contest (for this size sheet) so you can get a 15g sheet or a 20g sheet. I was just pulling sheets of a pile so thats prob where the weight difference is. Nigel- yes they're very light, the fuz with wing tube, canopy and rudder will be about 1050g, tails about 75g each and the wings 465g. So about 1665g ish for bare airframe uncovered. Havent got my converter so what 3 3/4 lb? Martyn- i will laterally balance the whole thing when its finished, hopefully just moving the lipos sideways will sort it! They weigh about 1200g Dan