[Construction] Quarter grain alignment .. UP?

From: izgo <izgo_at_yahoo.com>
Date: Thu, 22 Jun 2006 02:26:37 -0000

Hello

I used to cut wing ribs from a C-grain sheet, sanded to
desired thickness and using a template to cut wing ribs.
This gives me ribs with "A-grain" on top of rib.

Now, I read in Indoor Flying Models, by Lew Gitlow, on
page 95, figure showing a stabilizer, on top, he stands:
"POSITION STRIPS WITH QUARTER GRAIN UP".

So, from what Gitlow stands, I have to do the opposite,
cutting ribs from "true A-grain" sheet sanded to thickness,
so the top of the rib will be C-grain.

Question A)
Is this correct, C-grain should be at top of ribs?



Now, I have same dilemma for F1L prop spars. If I start
from a "square" section i will have 2 sides A-grain and 2
sides C-grain. I do a mark (on base) showing grain
orientation before rounding spar. Still I do not know
if I have to position "what was side A-grain" facing
forward (model moving direction) or facing prop rotation.

Question B)
Is any difference on grain alignment for spars, and what
is recommended?


Question C)
Following the same line, a F1L motorstick is better to
place C grain at sides OR C-grain at top/down?

Question D)
If B-grain is more suitable for motorsticks, does make
any difference the direction of the inclination of the
medullar rays of the cross-section?


Thanks in advance.

Ignacio.

PS: sorry for typos
Received on Wed Jun 21 2006 - 19:27:39 CEST