SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Mar 18, 2015, 11:58 PM
Registered User
Joined Mar 2011
1,438 Posts
Build Log
Diamond Demon 54"

Hi Guys! i decided to build a bigger DD, i will use an OS Max 15. As the plan i have is for FF and 34", some mods. will need to be done, as, spars and webs on wings, some work on fuselage.
it will be covered with silk, or maybe, some plastic, but is soon....

my thoughts are about the fuel tank....

some pics
colibriguitars is offline Find More Posts by colibriguitars
Reply With Quote
Sign up now
to remove ads between posts
Old Mar 19, 2015, 07:12 AM
Registered User
Paul_BB's Avatar
France, IdF, Lagny-sur-Marne
Joined Feb 2007
708 Posts
Good luck Rodrigo!
Paul_BB is offline Find More Posts by Paul_BB
Reply With Quote
Old Mar 19, 2015, 09:20 AM
Blueplaidcanard flyer
sdy. ny
Joined May 2007
3,078 Posts
It would be best to have the tank center line 3'8" to 1'2" below the carb center line if you can,as I remember my OS 15 did not have the best fuel draw.
rabidrue1 is offline Find More Posts by rabidrue1
Reply With Quote
Old Mar 19, 2015, 10:15 PM
Registered User
New Zealand, Canterbury, Christchurch
Joined Jun 2008
254 Posts
Hi Rodrigo,

I find it easier to fit the fuel tank at the right height in most vintage models if the engine is mounted inverted.

The downside is that you will have to provide cooling holes in the cowl but you will get a much smoother nose profile.

Others would argue that it doesn't look vintage without the cylinder sticking up like a sore thumb.

Either way that's a lovely looking design, I'm looking forward to your build.

I like the look of a silk finish. Coloured silk over laminating film seems to be the strongest/lightest/longest lasting finish these days.

Good luck with your build,

Dave H
gerryndennis is offline Find More Posts by gerryndennis
Reply With Quote
Old Mar 20, 2015, 08:41 AM
Registered User
United States, NY, Ithaca
Joined Sep 2007
1,064 Posts
Looking at that LG bulkhead, I see your problem!

If you haven't started construction yet I would be inclined to scale the plane a little larger. I flew a Livewire Champ with 600 square inches on an OS 15; it weighed slightly under 3 lbs and had a lot of sheet balsa in the construction. It could do consecutive loops and rolling circles. I bet you could go to 60 inches and still have plenty of power. You'll need to get your RX battery absolutely as far forward as possible.

My Champ had a 4 oz tank and seemed like it would run forever. Since then I have used 3 oz tanks (Hayes) with .15s. I think a 2 oz. tank would be less than I would want, unless you are doing just climb and glide, in which case you could use a small metal tank.

Jim
buzzard bait is online now Find More Posts by buzzard bait
Reply With Quote
Old Mar 21, 2015, 06:54 AM
Blueplaidcanard flyer
sdy. ny
Joined May 2007
3,078 Posts
The OS.15 I used was in a power pod on a Riser 100 sailplane and had no trouble getting the bird to height.You could re scale it to a size that would put the tank just below the cabin windows and be at 65 or 70".With the light looking frame work it should be light enough even at a 70" span.If you use muffler pressure to the tank you might get away with mounting it low in the fuse but I wouldn't bet on it.
rabidrue1 is offline Find More Posts by rabidrue1
Reply With Quote
Old Mar 29, 2015, 06:10 PM
Registered User
United States, SC, Charleston
Joined Feb 2013
129 Posts
I have put the tank in the cabin under similar circumstances. Worked fine and not really noticeable.....
pulserudder is online now Find More Posts by pulserudder
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Build Log AMPLAN diamond demon FF colibriguitars Vintage & Old-Timer Designs 30 Mar 11, 2015 11:43 PM
Sold Ben Buckle. Diamond Demon. RC Kit. Lower Price... VampeD4 Aircraft - Fuel - Airplanes (FS/W) 2 Feb 12, 2015 10:04 AM
Sold Ben Buckles kit of the Diamond Demon ronrange Aircraft - Fuel - Airplanes (FS/W) 3 Jul 04, 2014 10:40 AM
Sold Ben Buckle Double Diamond Demon Kit Broken Wings Aircraft - Fuel - Airplanes (FS/W) 1 Jun 06, 2014 05:55 PM