G-23 Prop revisited

Thread view:

Enable EMail Alerts

Start New Thread

Thread rating:

Dr1Driver - 22 Apr 2004 02:24 GMT

Ok, guys, I appreciate your suggestions on prop selection. Really. :) A lot
of you responded with your favorite recommendations.

What I learned today was on a 13 3/4-pound, 72" Dr.1 even largest recommended
size (18-8) doesn't do crap. I'd have hated to try to fly it with some of the
smaller suggested sizes. The G-23 had plenty of power, but the big Fokker
didn't have enough pull to get out of its own way. The engine was screaming but
the plane wasn't going anywhere. Can you say "cavitation"? I'm headed to the
hobby shop for a 20-5 or maybe even a 22-4. My first Dr.1 flew nicely at half
throttle with a G-38 swinging a 22-6. I believe a draggy plane like this one
needs the larger swept diameter/lower pitch for more pull and better
efficiency.

I used the recommended 2-cycle oil at 32:1. The engine ran fine on the test
stand, but cut out in the air on final approach. It's had 80 oz. through it so
far. Any ideas?
Dr.1 Driver
"There's a Hun in the sun!"

Reply to this Message

David AMA40795 / KC5UH - 22 Apr 2004 04:20 GMT

Weedie type engines take MUCCCCH longer to break in. Try 640 oz. thru
it before it starts running well. I'm gettng ready to fly a ~14lb
Super Cub with a Ryobi 31 - that spent several gallons worth of time
actually cutting weeds at our flying field <G>

David

>Ok, guys, I appreciate your suggestions on prop selection. Really. :) A lot
>of you responded with your favorite recommendations.
[quoted text clipped - 14 lines]
>Dr.1 Driver
>"There's a Hun in the sun!"

Reply to this Message

Dr1Driver - 22 Apr 2004 14:14 GMT

>Weedie type engines take MUCCCCH longer to break in. Try 640 oz. thru
>it

Damn! My G-38 didn't take almost 5 gallons to break in! I hope this one
doesn't take that much. Can you explain the difference between is running good
on the bench and then shutting off in the air?
Dr.1 Driver
"There's a Hun in the sun!"

Reply to this Message

Fred McClellan - 23 Apr 2004 00:01 GMT

>>Weedie type engines take MUCCCCH longer to break in. Try 640 oz. thru
>>it
>
>Damn! My G-38 didn't take almost 5 gallons to break in! I hope this one
>doesn't take that much. Can you explain the difference between is running good
>on the bench and then shutting off in the air?

The prop "unloads" in the air . . . . ?

Richen the mix and see what happens.
Cheers,
Fred McClellan
The House Of Balsa Dust
http://home.mindspring.com/~the-plumber

Reply to this Message

Dr1Driver - 23 Apr 2004 03:00 GMT

>The prop "unloads" in the air . . . . ?

Could be, Fred, could be...
Dr.1 Driver
"There's a Hun in the sun!"

Reply to this Message

Philip Rawson - 23 Apr 2004 00:33 GMT

Have you done the carb mod... Solder a tube into the hole in the diaphram
cover, connect fuel tubing and run it into the calm air inside the fuselage.

I have pics on my website...
http://www.flymodels.co.uk/whats%20on%20bb/pup/buildindboard.htm ... about
half way down the page.

--
Philip Rawson

www.flymodels.co.uk

> >Weedie type engines take MUCCCCH longer to break in. Try 640 oz. thru
> >it
[quoted text clipped - 4 lines]
> Dr.1 Driver
> "There's a Hun in the sun!"

Reply to this Message

Dr1Driver - 23 Apr 2004 02:59 GMT

>Have you done the carb mod

Never heard of it. I'll check your website. Thanks!
Dr.1 Driver
"There's a Hun in the sun!"

Reply to this Message

Jim P. - 23 Apr 2004 03:05 GMT

An 18-8 is too much prop. An 18-6 would be better.
The G23 is notorious for changing mixture with different airflow over the
carb. Some use baffles, some the tube mod, some a velocity stack.

> Ok, guys, I appreciate your suggestions on prop selection. Really. :) A lot
> of you responded with your favorite recommendations.
[quoted text clipped - 14 lines]
> Dr.1 Driver
> "There's a Hun in the sun!"

Reply to this Message

Model Forum / Radio Controlled / Air Models / April 2004

G-23 Prop revisited