How do you install the shear webs in a Chrysalis?
I just finished one wing half and upon closer examination of the
instructions (and the question on this site "What causes Chrysalis wing
failure on launch?") believe you intended the shear webs to be glued to the
AFT side of the spar caps. I have glued the shear webs CENTERED INSIDE and
between the upper and lower spar caps (I-beam style, just like the pre-cut
A-B, J-K1, and K2-L shear webs, as shown on the drawings). Would you
recommend leaving it as-is, or knocking the webs out and installing new
ones on the aft side of the spar, or just adding more shear webs on the aft
side. I have to admit it is difficult for me to tell from the instructions
exactly where on the spars (forward-aft direction) to glue the shear webs.
Thanks for any advice and clarification you can provide.
From Don Stackhouse:
David, sorry about your confusion. Actually, provided that you did a good
job fitting and gluing the shear webs, so that you have excellent quality
glue joints, installing the shear webs in the middle of the spar caps
I-beam style is stronger in most cases. We don't show it that way on the
plans because the typical beginning modeler would probably find that much
more difficult than installing them on the edges of the caps, box spar
style. What I would recommend is that you add a second shear web, still
I-beam style, right against the first, between ribs B and F. This takes
care of the concerns discussed in "What causes Chrysalis wing failure on
launch?". I would also recommend adding the extra balsa to the tops of the
finger pegs as discussed in the article, and being careful not to hook your
fingers over the tops of the finger pegs.
We periodically update our designs based on feedback from customer
experience, and the shear webs on the Chrysalis are one item we've targeted
for the next round of changes. Thanks for the feedback, it will definitely
be put to good use!
Don Stackhouse @ DJ Aerotech
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