HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Apr 29, 2014, 02:18 AM
Registered User
davereap's Avatar
Ashford. Kent. England
Joined Feb 2005
6,829 Posts
Build Log
" RM1 easy build Slopers" low cost any shape flying wings... "V" or Plank

I have recently come across a very simple build section that works well for flying wings.. of any shape...
V wings or planks

called the RM1 for its maker RustyMustard.. the sections idea thread is here
http://www.rcgroups.com/forums/showthread.php?t=2141726

Previously I have made a few KFm4 "Simple V" powered version wings, but getting into slope I am trying alternative build methods.

I cant do hot wire cutting so I am have been using KF sections which are working well.. But now I have a cheaper alternative.. cheaper as it uses a lot less glue.. and no CF spars.. and boy! does it fly nice....

This uses a slab of polystyrene builders insulation 1" thick from B&Q .
and the insulation material is only £2 per sheet white or grey .... I think the grey is slightly tougher/denser.. from 1 sheet you can make 2 smaller V wings at 1040mm or one big High aspect ratio one at 2M+ as the sheets are 1200 mm long x450 w x 25d..

So the cost on these is very low.. some pallet strapping spars( often free), woven tape for more strength and damage resistance, some colored tape for skinning and décor, and something for the fins.. depron or some recycled correx will do for fins and elevons..
The pricey stuff is the tape, but a roll will do 50m, and quite a few models
Total over here per model in the UK will be well less than £5 for a good Zagi alternative..

Zagis cost £36 over here for the glider version...from J Perkins.. they fly well, but so does this simple V...

I know what I prefer...
davereap is offline Find More Posts by davereap
Last edited by davereap; Jul 14, 2014 at 04:13 AM.
Reply With Quote
Sign up now
to remove ads between posts
Old Apr 29, 2014, 02:39 AM
Registered User
davereap's Avatar
Ashford. Kent. England
Joined Feb 2005
6,829 Posts
here are some pics through my build...

The polystyrene finish is not very smooth, so the coloured tape is reluctant to stick... I used a PU varnish to help this out.. but I didn't use enough .... next time I will try a covering iron to melt slightly and flatten the surface, or try a light spray of foam safe adhesive

pallet strapping , strong very sticky woven tape and coloured tape make it strong and stiff... see pic 3 for strapping and woven tape locations..

the coloured tape is applied as you would do a Zagi .. the tape is applied alternating , crossing over at the centre where its doubly thick.. that is best seen in the blue application pic 5

The pod is just a TLAR box, I made it a bit long out front to take a 1000 2s sized lipo but a 500 balances it fine ..so the pod can be shorter than seen here.. it was stuck on simply using thick UHU por and cool melt glue onto the tape below the wing
The gear can also be cut directly into the wing, but if you do this I would use lots more of the woven tape to keep the wing strong at the centre and move all the gear as far forward as possible to get your COG
I like the pod, it gives you a nice hand hold with which to throw the thing..
davereap is offline Find More Posts by davereap
Last edited by davereap; May 09, 2014 at 06:40 AM.
Reply With Quote
Old Apr 29, 2014, 02:44 AM
Registered User
davereap's Avatar
Ashford. Kent. England
Joined Feb 2005
6,829 Posts
here are the lines.. my model came out a fraction smaller at 1M span

the elevons were 2.5" at the root going to 2" at the tips. . made from 6mm depron all tape covered, as were the triangular fins.. elevons made overlong to cut to the angle, then cut at the angle they will measure more..
fins are 4.5" deep at the rear and are lined up with the lower wing surface

calculate your COG using this calculator set for 25% and 20% in the option box... http://wingcgcalc.bruder.com.br/en_US/?
mark up the two locations and make sure you can adjust the weights so as to obtain both..
20% is a good starter in higher winds , but you might need 25 or more in light conditions...
at 30 it will get pitch sensitive, but very low rates will manage it providing its in light winds
davereap is offline Find More Posts by davereap
Last edited by davereap; May 09, 2014 at 06:37 AM.
Reply With Quote
Old Apr 29, 2014, 03:00 AM
Registered User
davereap's Avatar
Ashford. Kent. England
Joined Feb 2005
6,829 Posts
I tried this out in zero lift conditions from my dunes.. the glide is great, the control is great, all very smooth.. so I am well impressed... it was as good as my KFm wings and Zagi , time will tell if its better.. but its far cheaper...

wing area for my 1M version is 3.4sqft.... wing loading is 4ozsqft with a 500 2s lipo in the hatch.. about the 13.5oz AUW
that's a fraction less than my Zagi, which has 3.5sqft and weighs 14.75oz for a 4.2ozsqft loading

gear used ... orange 2.4 RX.. 3A BEC.. 2x turnigy 9018mg servos.. 500 2s lipo.
davereap is offline Find More Posts by davereap
Last edited by davereap; Apr 29, 2014 at 03:56 AM.
Reply With Quote
Old Apr 29, 2014, 03:59 AM
Registered User
davereap's Avatar
Ashford. Kent. England
Joined Feb 2005
6,829 Posts
Thinking about this wing , it could be easily adapted with a couple of ply plates and some pegs to take the swappable pod used by the flite test builds.. then you can use it for power or slope as you want
davereap is offline Find More Posts by davereap
Reply With Quote
Old Apr 29, 2014, 05:11 AM
Registered User
WindOverMatter's Avatar
United Kingdom, England, Kent
Joined Mar 2014
83 Posts
Have you tried this profile on a powered wing? It looks simple and strong, but very flat.
WindOverMatter is offline Find More Posts by WindOverMatter
Reply With Quote
Old Apr 29, 2014, 01:59 PM
Registered User
davereap's Avatar
Ashford. Kent. England
Joined Feb 2005
6,829 Posts
Hi Vince.......
only on a slope glider so far... Ive always used KFm4 for powered wings.. but this is a cheap alternative and B&Q is just down the road.. depron has to be ordered on line.. when its all tape covered its feel is much like a Zagi, stiff and strong.. and they go well slope or powered

Ive just started on a weasel shaped plank using the same foam and method..
see further on
davereap is offline Find More Posts by davereap
Last edited by davereap; Jun 20, 2014 at 11:34 PM.
Reply With Quote
Old Apr 29, 2014, 04:31 PM
Registered User
WindOverMatter's Avatar
United Kingdom, England, Kent
Joined Mar 2014
83 Posts
I'll have to try it some time. I have been meaning to get to some hot cutting, so source of cheap foam is always a good thing.

In a way I like the way this profile has built-in reflex, but I'm not sure how I feel about not having the option to dial it out. Of course, with a single-purpose aircraft, that should never be an issue.
WindOverMatter is offline Find More Posts by WindOverMatter
Reply With Quote
Old Apr 30, 2014, 01:54 AM
Registered User
davereap's Avatar
Ashford. Kent. England
Joined Feb 2005
6,829 Posts
Its a single use section... for flying wings of any shape.. they always seem to need just a touch of reflex, usually you give it up elevator trim...
for gliding this adds drag .. reflex built in seems to be best...
The simple V had only the slightest up set on the elevator...

Have a look at this great flying wing for the slope... http://www.rcgroups.com/forums/showthread.php?t=1456458 the wing is hot wire cut and has its reflex in its aerofoil shape..

The RM1 section does a similar job...

Next build a powered version.. or a lighter version for low lift.....but first I will get this slope wing nicely sorted ...
davereap is offline Find More Posts by davereap
Last edited by davereap; May 09, 2014 at 06:42 AM.
Reply With Quote
Old May 08, 2014, 02:32 AM
Registered User
davereap's Avatar
Ashford. Kent. England
Joined Feb 2005
6,829 Posts
here its maiden flight.. wind at about 20mph..
note... The COG was ok but it could have used some more ballast for better penetration..
I did add 2oz ballast , this was just enough.. more might have been better
Being new to the slope I am still getting used to flying in these high winds, its frightening enough just launching when its blowing this hard...lol
Its HD so watch full screen HD for a better view.. simple loop and rolls at 4.05ish to show the response as setup here
.
SimpleV an easy build sloper V wing Maiden flight at Wye (8 min 15 sec)
davereap is offline Find More Posts by davereap
Last edited by davereap; May 09, 2014 at 06:45 AM.
Reply With Quote
Old May 09, 2014, 08:51 AM
Registered User
Joined Apr 2013
497 Posts
Quote:
Originally Posted by WindOverMatter View Post
Have you tried this profile on a powered wing? It looks simple and strong, but very flat.
Dave's airfoil approximates a "real" airfoil to some degree - I think it would be fine under power.
Besides, with low enough wing loading and aspect ratio even a thin, flat plate flies reasonably well under power.
nuteman is online now Find More Posts by nuteman
RCG Plus Member
Latest blog entry: My youtube channel
Reply With Quote
Old Jun 09, 2014, 05:50 AM
Flying one day at a time....
pardshaw's Avatar
United Kingdom, Pardshaw
Joined Oct 2012
1,463 Posts
Hi Dave, just found this thread - and Rusty's on the RM 1.


Your build technique and Rusty's RM 1 airfoil look great to my eye. I'm gonna have a go myself.


For reasons I can't even begin to explain I prefer the Wisel planform over the Zagi V-wing planform. No idea why, pure prejudice on my part I guess!


So, I think I'll steal your build methods and Rusty's RM 1 foil and try them out on a Wisel planform (like you did .... here http://www.rcgroups.com/forums/showp...&postcount=423 ). That way I'll have a good point of comparison (I mainly slope using Wisels).


Dave
pardshaw is offline Find More Posts by pardshaw
Last edited by pardshaw; Jun 09, 2014 at 05:56 AM.
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
New Product FFBLG: Low Cost, Simple Brushless Gimbal for Multirotors mklinker Multirotor Talk 1239 Aug 13, 2014 01:25 AM
Build Log Low cost FPV setup for flying wings varvar FPV Equipment 5 Mar 15, 2014 07:45 PM
Discussion My simple and low-cost quad jmdhuse Scratchbuilt Multirotors 0 Oct 15, 2013 04:22 PM
Idea EDF50 Rotor Retention, low cost, simple solution scratchandbash Electric Ducted Fan Jet Talk 34 Oct 11, 2009 03:36 AM
Simple low cost 3D cad software wanted CloudyBright The Builders Workshop 14 Feb 02, 2005 06:14 PM