On Nov 5, 11:06*am, bildan wrote:
I have to refurbish/replace my wing wheel assembly and need some
suggestions/insights. *The current one is the typical aluminum wing
cuff and bicycle wheel. *It wasn't well made to start with and it's
falling apart. *I want to take this opportunity to improve the thing.

One of the biggest issues I see is that if the cuff isn't perfectly
aligned on the wing, the wheel will try to track sideways and cock the
cuff risking wing damage. *Further, it's a big chunk of "stuff" that
takes up space in the trailer or retrieve vehicle.

My first thought is that there are already wing cuffs used as wing
supports in the trailer. *One of these might serve a second purpose as
a wing cuff for the tow out gear if I made it a little wider and added
attach points for a wheel. *This would eliminate the need to find
extra space for it.

My second thought is to use a castering wheel instead of a fixed one.
This would prevent lateral and twisting forces from being transferred
to the wing. *Even if the wing cuff wasn't perfectly aligned, it
wouldn't matter. *The wheel/fork/steering head from a child's bicycle
might be adapted. * I'm thinking that the typical ~20" wheel is much
larger than it needs to be.

Further thoughts about wheels leads me to think a bicycle tire is
designed for traction which isn't really needed in a wing wheel. *In
fact, it would probably be better if it would slide sideways more
easily than a rubber tire. *Pneumatic tires also can go flat. *Maybe a
solid plastic wheel from some other source would be better.

Any thoughts?

I think all of the points you raise are on target. I have a
"factory" Anschau (Komet) wing wheel with the padded fiberglass
cuff. It does suffer from the twisting issue you describe. I made
two modifications to mine:

1. Replaced the existing pneumatic tire with a 14" solid tire with a
spoked plastic wheel. I had nothing but trouble with the pneumatic
tire, especially with the bead being pulled off the tire when the
lateral loads were applied. I must have replaced the tube 5 times
over 2 years. I think you do want to account for the loss of some
shock absorbtion if you go with a solid wheel; the factory unit I
have has a gas strut that allows the unit to collapse slightly under
load.
2. Added 8 pounds of weight to the bottom of the cuff. This
counteracts the tendency to sometime drop the opposite wing if there
is a wind gust or some other upset. I've seen guys split an aileron
when the wing falls at just the wrong moment, especially when towing
the glider with water in the wings.

FWIW, I think a well-made aluminum cuff (i.e. properly shaped to match
the wing profile and well padded) is much easier to pull off than a
home-built fiberglass version.

P3