rtfm
Well-Known Member
Hi,
Some advice sought:
I plan to build my entire wing skin in two parts - top/bottom - terminating at the flap/aileron secondary spar. Each skin will be laid in a female mold, and built up from triax glass cloth/3mm Airex foam/triax cloth. In addition, I am using 2.34mmx5.59mm rectangular rods as my spar cap, and am simply going to cut out the required channel in the foam to accommodate the rods. Then sandwich the whole lot in a single vac infusion. This should give me a a .6mm depression on the inside into which I plan to bond the shear web.
The shear web will be built up from a non-continuous tongue & groove style interlocking arrangement. To the bottom wing skin, I'll bond two 3mm glass/foam/glass sandwiched panels, separated by sufficient space to allow the third "male" part of the joint to slip between them. These panels will far exceed the usual shear web in strength, so I do not need to have this as a continuous piece. I will terminate them on either side of the ribs.
Bonding the two outside panels will require some accuracy, but should be simple enough to do. Once bonded, the third inner panel is then "spot-bonded" into place while fitting the top and bottom wing skins together. This will ensure accuracy, and will be fairly straightforward. Once set, the final bonding is easily completed.
The shear web "joint" is fully bonded as part of bonding the two wing skins together.
The advantage of this method are:
How best to bond the shear web panels? The wing skin will be Vinyl-ester.
Thoughts? (Other than this is a solution-looking-for-a-problem type of reply...)
Regards,
Duncan
Some advice sought:
I plan to build my entire wing skin in two parts - top/bottom - terminating at the flap/aileron secondary spar. Each skin will be laid in a female mold, and built up from triax glass cloth/3mm Airex foam/triax cloth. In addition, I am using 2.34mmx5.59mm rectangular rods as my spar cap, and am simply going to cut out the required channel in the foam to accommodate the rods. Then sandwich the whole lot in a single vac infusion. This should give me a a .6mm depression on the inside into which I plan to bond the shear web.
The shear web will be built up from a non-continuous tongue & groove style interlocking arrangement. To the bottom wing skin, I'll bond two 3mm glass/foam/glass sandwiched panels, separated by sufficient space to allow the third "male" part of the joint to slip between them. These panels will far exceed the usual shear web in strength, so I do not need to have this as a continuous piece. I will terminate them on either side of the ribs.
Bonding the two outside panels will require some accuracy, but should be simple enough to do. Once bonded, the third inner panel is then "spot-bonded" into place while fitting the top and bottom wing skins together. This will ensure accuracy, and will be fairly straightforward. Once set, the final bonding is easily completed.
The shear web "joint" is fully bonded as part of bonding the two wing skins together.
The advantage of this method are:
- The spar caps are an integral part of the wing skin itself
- The wing airfoil accuracy is greatly enhanced, because it is a single molded surface
- The spar cap-to-skin bond is maximised
- The shear web is easily strong enough that it doesn't need to be continuous
- Easy fitting of the ribs
How best to bond the shear web panels? The wing skin will be Vinyl-ester.
Thoughts? (Other than this is a solution-looking-for-a-problem type of reply...)
Regards,
Duncan
