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Old Sep 12, 2012, 06:51 PM
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Originally Posted by klique View Post
i read every day and always know you are all having a blast keep it up guys,,,
+1:d
i will hopefully eventually get some of these sport wing molded in epp.
+1000
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Old Sep 12, 2012, 06:54 PM
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Is it a good idea or not to cut down a prop diameter to get more motor RPM's.

example: 6.5x6.5 cut down to 6x6.5
Old Sep 12, 2012, 07:01 PM
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Originally Posted by BpPilot View Post
To the random reader, it probably sounds like we never have any fun actually flying these things. Always pushing the limits of our equipment, and always wanting a few more mph...
BP,
I can see your point if you were unfamilar with what we are doing. I have 5 Ritewings now and I think they are great since they are fun and low stress when that's what you want but there is also definite excitement when running things to the very edge too.

I also think there is a few geeks here that also enjoy the techical aspects too (gotta confess to that attaction!)
Old Sep 12, 2012, 07:17 PM
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Hi Brad,
How discharged was the battery and how much load was on there on the motor (accelerating hard or level and unloaded?) when you made that calculation?

More importantly- Is it fun to fly?
It was straight and level but still accelerating I think. Only WOT for 2 seconds, that's where I read the voltage.

It's a blast to fly! Launches are pretty easy with the 6.5 dia prop. Landings are still a little tricky for me, I have limited space.
Old Sep 12, 2012, 07:20 PM
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Originally Posted by brolley View Post
Is it a good idea or not to cut down a prop diameter to get more motor RPM's.

example: 6.5x6.5 cut down to 6x6.5
Brad,
It's fine to cut your prop tips to get more rpm but whether you actually go faster is another thing!

(There is usually a tradeoff between thrust and pitch speed for the same input power and the thrust required to overcome the drag of the wing increases generally exponentially with every mph increase)

So if your Demon is only doing say 120 mph, it will be probably increase the speed but if it's doing say 160 now, it may actually go slower.

So try it and see what result you get!

(I did some testing of 6.5 inch diameter props in a high powered Demon early this year and found that it would take about 8 seconds of motor run to have the prop fully unload. 8 second is a long way! I'm thinking now if I upped the prop diameter to 7 inches to increase thrust and decreased the pitch slightly it would go faster but haven't got around to trying it yet.)
Old Sep 12, 2012, 07:37 PM
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never mind the boll⁣⁣⁣ocks
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just let me know when you want to go FPV peter and we can go as much throttle for as long as you want none of these little 8 second runs :P
Old Sep 12, 2012, 07:38 PM
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Originally Posted by brolley View Post
It was straight and level but still accelerating I think. Only WOT for 2 seconds, that's where I read the voltage.

It's a blast to fly! Launches are pretty easy with the 6.5 dia prop. Landings are still a little tricky for me, I have limited space.
So assuming you took the reading about a quarter of the way through the flight, you would pick up a tiny little more rpm but I guess you would have to weigh up if getting another 50 watts or so is worth the $$$$!

Those batteries may also be helping safeguard your motor too!
Old Sep 12, 2012, 07:41 PM
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Originally Posted by brosius85 View Post
just let me know when you want to go FPV peter and we can go as much throttle for as long as you want none of these little 8 second runs :P
LOL! Can you also imagine how high we could make the dive!
Old Sep 13, 2012, 09:46 PM
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Damn... Sounds like you all are having fun while I'm taping and painting. I wish I would have gone with a simpler paint job. I don't have the patience when waiting for paint to dry.

It does make a nice addition to the living room though.
Old Sep 13, 2012, 11:48 PM
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RLC,
I'd say your time and care in designing and painting your wing has paid off VERY well.
Love the theme.

...you Rebel scum...

Old Sep 14, 2012, 02:47 PM
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PU skim coat question. How long before its sandable? Its been almost 24 hours and it's tough to sand because it's slightly "spongy". Or is that the final texture? (it's not foamed up spongy because I kept pressing it down for 30 min after coat).
Last edited by Vtrockin; Sep 15, 2012 at 08:09 AM.
Old Sep 15, 2012, 06:50 AM
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never mind the boll⁣⁣⁣ocks
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depends.... haha, if it is hot weather you should be cured by now, if it is cold give it another day.
Old Sep 15, 2012, 09:31 AM
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Posted a video in the electric airplane section.... don't expect too much.
Old Sep 15, 2012, 01:50 PM
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Seriously...is this how a PU skim coat supposed to look? In CK's video it doesn't look all bubbly when he does the front bottom. I have a piece of plastic than I smooth push it down as it dries, but it never turns out very smooth. What's up? What am I missing - or is it really a lot of elbow grease after?
Old Sep 15, 2012, 03:40 PM
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Mum is the word!
Then sand it , then fill with spackle and sand it if you want it smoth, I dont usually fill ,then paint it then a coat of 90 , let dry for a day them lam.
An electric palm sander does a great job.
I use rustoleum double coverage glossy.

Quote:
Originally Posted by Vtrockin View Post
Seriously...is this how a PU skim coat supposed to look? In CK's video it doesn't look all bubbly when he does the front bottom. I have a piece of plastic than I smooth push it down as it dries, but it never turns out very smooth. What's up? What am I missing - or is it really a lot of elbow grease after?


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