: Mick, good points. The way Valley and NDK do it is by molding two large round
: washers on each side of the pivot point of the skeg blade. Then the bungee
: wraps around these large washers. It provides more leverage and also helps
: hold the skeg blade in place without requiring a pivot bolt. If there's a
: rock in there, the bungee still doesn't provide enough torque to get it to
: drop out. The only thing I know of that works is to have a friend paddle
: to your stern and pull on the string that is attached to the end of the
: skeg blade. Same with the wire systems I've used.

(i didn't know that some were out there that have no pivot at all - i remember that clc has a ledge - but their's is one system for sure that i'd totally eliminate the pivot and put in a continuous top line and deck over. the upper knob would just follow under the deck. but that's a large poorly designed system anyway)
the way i'd do it (we're talking line systems here - other types obviously different) would be to have the deploying bungee attached to a line to the ckpt instead of just stopping near the hole in the deck. that way you still have the bungee spring, but then can really ream up on it if necessary - therefore others not needed.

: Whoops, I forgot to mention that washers are needed between the skeg blade
: and the skeg box. I used rubber washers. The rubber washers in combination
: with the 1/4" bungee running on each side effectively eliminated slop
: and vibration. I need to update the article. This is why I need you guys
: looking at these things.

you're ahead of the game - sorry, i didn't realize it.

: I'm not sure that you'd get enough torque by having the bungee there. Bjorn's
: system uses two static lines connected to the skeg. It may work, but the
: pivot increases the torque on the bungee. Am I understanding correctly?

i like bjorns system as there is sorta equal forces available. if either of the lines had partial bungee like above, then could play with no pivot as well. or maybe if just lines then continuous loop around a friction pulley (that could be under tension maybe to provide the tension), no pivot req'd either.

: That's the positive about the NDK or Valley system - they don't have a pivot
: point bolt on there bungee systems. By having a pivot point instead of
: just having the bungee hold the system in place, I was hoping to avoid any
: potential problems of having the skeg blade fall out if the bungee breaks.

as the deploy is the bungee, all you do is keep the retract line tied up - there's no where for the skeg to go but stay in the box. (maybe would have to finesse it a bit on setup - but the basically there are 2 lines attaching the skeg = redundancy

: The pivot point on the skeg blade ensures that if the bungee breaks, the
: skeg won't fall out of the box. By cutting a slot in the blade to slot it
: onto the pivot point, it's still easy to remove. That was my thinking
: anyway. I think both approaches are valid, and I'm probably worrying too
: much. Bungee doesn't break that often.

i think the approach basically used by bjorn is the one i like best, but the big issue on a skeg that deploys 90 deg is that the retract line or bungee insert into the skeg is exposed.

an idea i remember writing about years ago is to take 3 plies of 1/8" plywood and cut them just like your skeg shape. take one of the plies and cut one of the diameters off and trim it down by say 1/2 in less diameter. then glue all the plies together and get a built in pulley in on the upper end when sandwiched between the other full plies. then i'd foil shape the blade end but not the inset end. (glass and/or epoxy ea pc before ass'y for water protection)

the deployed end of the skeg shape should be part of a circle that uses the pivot as the radius point (not the same as the insert end). (might as well make the shape as geometrically as efficient as possible.

then i'd take the skeg itself and wrap it in some 1/8" foam and use that as the form for the box - so get a really nice fit. hot glue as req'd to set up - easy to remove later. i'd add a little foam around the bottom so that the box would end up with just a tiny upside down 'V' shape to expel sand and stuff. and for sure do like nick does and put it just off centre unless the yak is flat bottomed - then either ctr or twinned up sides.

then like before, bungee and line deploy to the ckpt and just line retract to the same ckpt location also and make them into a continuous loop around a friction (not a jam) fitting. that way could maybe get quick reliable control. maybe a visual tag on the line so know what the angle set down.

anyway ideas,

mick