Javier,
I've just completed a mod and PFA application siting the battery just rear
of the flap cross tube on the fuselage floor.
Carve and sand a foam block to fit the floor shape; make the block about
35mm bigger all round than the battery base. If you're using a wet lead
acid, arrange the inclination of the battery to be 3.5 degrees down at the
front, In this way the battery will be +3.5 degrees in flight and -3.5
degrees in the hangar. If it's a gel battery this doesn't matter. Make a
tray (frame) from Al angle 25 x 25 mm and 1.5 mm thick walls and drill 6
off 3/16" fastening holes. Make a ply base 20mm bigger all around than the
battery and fit captive nuts to the ply under side to match the Al tray's
fastening holes. Bung up the holes with plasticine to stop the resin going
in when you glass it in position.
Let the ply wood into the foam, then glass over and on to the floor, 2
plies bid all over, 50mm lap and flox in the corners.
Make one strap from 15 mm polyester webbing and side release buckles
wrapping under the al. tray and over the battery. Soak the corners of the
strap in resin for local stiffening. Trap the strap under the al. tray.
My tray was 175 x 97 to suit a Varta lead acid 12v 19 Ah 51912. Mass 5.5kg.
I've tested it to the VLA limits for single loads (3g up, 9g forward, 1.5g
side) no permanent deformation or sproings.
If you need the drawings from PFA my Proj no. is 247-12622
Good luck
Dave Simpson
----------
> From: Javier Barahona <jbarahona@carrotnet.com>
> Subject: battery
> Date: 06 December 1998 15:35
>
> Please, can anyone give me some tips for the construction of a battery
> mount.
>
> Thanks.
>
> Javier Barahona, Builder 187
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