Hi Cristobal
Apologies for the delay in replying - I've been away for the last week and am just catching up now.
The length of the wings shouldn't make any difference to the metal wing junction fittings - longer wings just give you different flight characteristics (efficiency, glide ratio, wing-loading, sink rate, etc). The load on the fittings should (I think) remain the same... though I'm open to correction here!
I see from the set of plans (page 3 / Sheet 2 of the pdf file) on this website that the original wing junction fittings were made out of 0.125" thick 4130 steel with a load bearing strength of 125,000 psi. 4130N steel actually has a bearing strength of 140,000psi - so you need to know the precise material your fittings are fabricated from.
carbon-dragon.ihpa.ie/index.php/cd-build...ototype-cd#woodstock
If you know the all-up weight of the glider (glider + pilot + everything else you take with you) then you can work out the required strength and dimensions of the metal fittings yourself and compare your figures to the actual fittings you have. You can see how I calculated the requirements for my wing fittings here (using Jim Marske's method) here:
carbon-dragon.ihpa.ie/index.php/cd-builders/phil-lardner-s-cd#modifications - 3-Part Wing - Analysis.
If that's beyond you, or it takes you out of your comfort zone then I can do the calculations for you... if I find a spare evening... but that could be some time!
If you're doing the calculations yourself then you need to take your all-up weight and multiply it by 1.5 to give you the standard safety factor at 1g. You then need to multiply that number by 5 to get your maximum design load (or x8 to get your ultimate load limit - where the fittings are expected to fail.) Use the all-up weight x 1.5 x 5 number in your calculations.
Strictly speaking you do not need to include the weight of the wings themselves as they are considered to lift their own weight and do not react it through the wing junction fittings.
You'll find a full description of how to design and calculate wing junction fittings in Jim Marske's excellent Composite Design Manual, available here:
www.marskeaircraft.com/
Hope this helps,
Phil.