Building the Brake
The building of the landing brake started in an earlier chapter when the brake was cut out but then re-glassed back into the fuselage bottom until Ch 9. So the completion of the brake starts with cutting it lose.
I decided early that I wanted the hinge for the brake to go almost the full width instead of just 10" per the plans. I'm hoping this will keep it from warping the way several builders have reported. To do this, all I really had to do is adjust the number of attach points/screws. I'm also widening the wooden support the actuator connects to to provide a little more crosswise support. My hinge runs ~22" of the ~24" width of the LB.
Installing the Brake Hinge Support
I used 7 screws to attach the hinge to the fuselage and 8 screws attaching the hinge to the LB. Other than the added number of screws/slugs to the hinge line, everything else pretty much followed plans.
Preparing the LB Cavity in the Fuselage
After securing the LB-23 hinge support into the fuselage, I routed out the interior of the landing brake cavity using a dremel routing tool to make room for the glass to be added.
|Glassing the cavity|
|Routing out the fuselage cavity|
|Micro curing in the depression|
surrounding the landing brake. The
boards ensure the brake sits flush
with the bottom of the fuselage.
Installation of the Actuator
I'm using a Firgelli actuator, model FA-PO-150-12-4. It has a 4" stroke, 150lbs of static force, and a feedback potentiometer in case you want to wire it up to an electronic indicator. I made glass brackets similar to Wayne Hicks however I only ended up using the larger one to attach the actuator to the back of the seat.
The brackets were made similar to Wayne Hicks brackets, with 8 ply of BID...4 running along the bottom, 4 running from the bottom and up the side on each side, with another 4 layers forming a U-shape in between the sides. A picture would be good here, but at any point on the bracket there are 8 layers of BID. I used a scrap piece of foam to form around which was cut the width of the actuator attachment. I let it cure, cut it to shape, put adjustment holes in it to allow me to adjust the closure of the LB once installed.
|Assessing where to mount the bracket|
on the seat back.
Between the seat and the birch, I embedded two EZ-point locking nuts vertically where two bolts hold the bracket in place. The actuator is then attached to the bracket with an AN Pin and castle nut to secure it. For the LB bracket, I simply used the aluminum brackets, part no. CZLB-18 available from the Cozy Girrls.