cozy gear doors

[lacoss]

I am ready to install the gear doors on my cozy and the mounting of the doors is pretty straight forward. I have not yet figured out the best mechanical method to use to open/close the doors. Any suggestions?

[Wayne Hicks]

I am assuming by "gear doors", you mean gear doors that are actively eployed/retracted separately to close off the entire wheel well as opposed to the plans-specified cover.

 

Okay, most gear doors I've seen are two doors hinged along the outside edge of the wheel opening. Most approaches use two doors because a single door is too wide. It will impact the ground when the nose is parked on the ground.

 

There are generally four deployment schemes. Each method relies on the nose strut or nose wheel to open and close the doors. But more importantly when deploed, each holds the doors in a fixed position so that the doors don't open too far or close inadvertently from the onrushing air.

 

The four schemes I'm aware of:

 

(1) Door spring -- a length of door spring is mounted to the insides of each door near their fronts. Upon retraction, the strut pulls the spring up into the wheel well, thus pulling the doors closed. Upon deployment, once the strut to deployed far enough the spring naturally forces itself straight and forces and holds the doors open. Some builders angle the front edges of the doors outward so that air pressure helps to hold the doors open.

 

(2) U-bracket and/or music wire -- a strip of thin metal is fashioned into an inverted U shape. The ends are hinged onto the doors. The U curvature fits around the nose tire. When the strut is retracted, the nose tire nestles into the "U". The tire pulls the U-bracket upward, thus pulling the doors closed. The process is reversed to open the doors. (Some builders use a spring to help push the U-bracket downward to hold the doors open.) The sides of the U-bracket keep the doors from opening too far, or from collapsing back inward.

 

(3) Mechanical Linkages -- three rods (or more)that perform the same function as the U-bracket.

 

(4) There are other variants of linkages too.

 

I'll see if I can gen up a figure of the types I'm aware of. In the mean time you can check these peoples' websites:

 

James Redmon

http://www.berkut13.com/berkut13.htm

 

Wayne Hicks

http://www.maddyhome.com/canardpages/pages/waynehicks/chapter_13_3.htm

 

Jerry Schneider

http://home.earthlink.net/~jerskip/cozy_015.htm

 

John Slade

http://www.kgarden.com/cozy/chap13b.htm

 

Rick Maddy

http://www.maddyhome.com/cozy/chapter?c=13&s=8

[Wayne Hicks]

Besides needing to use a spel cheecker (sic), should we move this topic to Chapter 13?

[lacoss]

I would have put this in chapter 13 except I did not really know which chapter this was. I am working with parts bought originally by another builder and there is a mixture of prefab aerocanard parts in it so the plans do not cover a several of the operations. I depend a lot on pictures posted by other builders.I usually have to ask a lot of questions before I am comfortable with the direction I should go. Thanks for the links. I'll check them out.