SMALL - espritmodel.com SMALL - Telemetry SMALL - Radio
Reply
Thread Tools
Old Sep 12, 2012, 05:51 PM
Registered User
brolley's Avatar
United States, PA, Center Valley
Joined Dec 2008
393 Posts
Quote:
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
brolley is online now Find More Posts by brolley
Reply With Quote
Sign up now
to remove ads between posts
Old Sep 12, 2012, 05:54 PM
Registered User
brolley's Avatar
United States, PA, Center Valley
Joined Dec 2008
393 Posts
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
brolley is online now Find More Posts by brolley
Reply With Quote
Old Sep 12, 2012, 06:01 PM
Registered User
Peter M's Avatar
Newcastle, New South Wales, Australia
Joined Sep 2007
2,366 Posts
Quote:
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!)
Peter M is offline Find More Posts by Peter M
Reply With Quote
Old Sep 12, 2012, 06:17 PM
Registered User
brolley's Avatar
United States, PA, Center Valley
Joined Dec 2008
393 Posts
Quote:
Originally Posted by Peter M View Post
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.
brolley is online now Find More Posts by brolley
Reply With Quote
Old Sep 12, 2012, 06:20 PM
Registered User
Peter M's Avatar
Newcastle, New South Wales, Australia
Joined Sep 2007
2,366 Posts
Quote:
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.)
Peter M is offline Find More Posts by Peter M
Reply With Quote
Old Sep 12, 2012, 06:37 PM
never mind the boll⁣⁣⁣ocks
brosius85's Avatar
Australia, NSW
Joined Dec 2010
1,256 Posts
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
brosius85 is offline Find More Posts by brosius85
Reply With Quote
Old Sep 12, 2012, 06:38 PM
Registered User
Peter M's Avatar
Newcastle, New South Wales, Australia
Joined Sep 2007
2,366 Posts
Quote:
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!
Peter M is offline Find More Posts by Peter M
Reply With Quote
Old Sep 12, 2012, 06:41 PM
Registered User
Peter M's Avatar
Newcastle, New South Wales, Australia
Joined Sep 2007
2,366 Posts
Quote:
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!
Peter M is offline Find More Posts by Peter M
Reply With Quote
Old Sep 13, 2012, 08:46 PM
Something Something RC
rlc2052's Avatar
United States, PA, Philadelphia
Joined Nov 2010
122 Posts
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.
rlc2052 is offline Find More Posts by rlc2052
Reply With Quote
Old Sep 13, 2012, 10:48 PM
Victim of C.D.O.
murdnunoc's Avatar
United States, TX, Lubbock
Joined Oct 2007
4,081 Posts
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...

murdnunoc is offline Find More Posts by murdnunoc
Reply With Quote
Old Sep 14, 2012, 01:47 PM
Registered User
Vtrockin's Avatar
United States, VT, Burlington
Joined Jan 2012
70 Posts
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).
Vtrockin is offline Find More Posts by Vtrockin
Last edited by Vtrockin; Sep 15, 2012 at 07:09 AM.
Reply With Quote
Old Sep 15, 2012, 05:50 AM
never mind the boll⁣⁣⁣ocks
brosius85's Avatar
Australia, NSW
Joined Dec 2010
1,256 Posts
depends.... haha, if it is hot weather you should be cured by now, if it is cold give it another day.
brosius85 is offline Find More Posts by brosius85
Reply With Quote
Old Sep 15, 2012, 08:31 AM
Registered User
brolley's Avatar
United States, PA, Center Valley
Joined Dec 2008
393 Posts
Posted a video in the electric airplane section.... don't expect too much.
brolley is online now Find More Posts by brolley
Reply With Quote
Old Sep 15, 2012, 12:50 PM
Registered User
Vtrockin's Avatar
United States, VT, Burlington
Joined Jan 2012
70 Posts
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?
Vtrockin is offline Find More Posts by Vtrockin
Reply With Quote
Old Sep 15, 2012, 02:40 PM
Mum is the word!
Joined Jun 2003
6,785 Posts
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?
klique is offline Find More Posts by klique
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
I got some Fan Fold what to build thread part II started by emoone!!! Don Sims Foamies (Kits) 188 Jan 23, 2010 08:28 PM
Build Log RiteWing 48-FT build thread theclaw Slope 46 Dec 09, 2007 08:53 AM
Mountain Models Tantrum Partial Build Thread.. Tram Parkflyers 142 Apr 03, 2004 10:41 PM
My Bobolink Build Thread (very Colibri like) Jim Poor Hand Launch 65 Dec 10, 2003 04:48 PM
Switchback re-build thread (or What the $#*& was that!) Biggles604 Parkflyers 17 Jun 23, 2003 09:34 PM