Re: Re: Exact Builder of Model Rule

From: Jake Palmer <82.jake_at_gmail.com>
Date: Thu, 30 Jan 2014 12:33:18 -0800

Kang,

I don't have my notes in front of me, but I know my lightest tube was
~100mg before gluing the seam. My seams only weigh 6 or 7mg. Add in 2
boron and I have a finished tube weight of ~115mg. Assuming your tube is
10.25" long and weighed 130 before gluing the seam, that means you're using
~4.7# wood. I'm using 3.8# wood. I've loaded my models with a motor wound
to .42 in/oz before without a problem (at least not a problem for the motor
tube, but I've had motors break on the model).

For reference, back in the days of 65cm models we used 14.5" long motor
tubes made from 3.8-4.0# wood and they worked. By comparison the 10.25"
sticks of 55cm models are quite robust.


On Thu, Jan 30, 2014 at 12:06 PM, <ykleetx_at_gmail.com> wrote:

>
>
> Jake,
>
>
> If your 10" F1D motor tube is really 100 mg, then you would have collapsed
> it for sure, even if you wound the motor modestly.
>
>
> My tube with glue is 138 mg, with 2 borons, 146 mg, with 4 borons, 154 mg.
>
>
> If a carbon tube can be built to 180 mg, that's a 30 mg penalty, not 100
> to 150 mg.
>
>
> -Kang
>
>
>
Received on Thu Jan 30 2014 - 12:33:19 CET