HobbyKing.com New Products Flash Sale
Reply
Thread Tools
Old Jan 20, 2013, 02:10 AM
InceCreations
vincent123's Avatar
Joined Jul 2009
732 Posts
It would be great to have it powered, spread out to land, fold together when speeding!

Looking at your plank design, you work very accurately, nice work.
vincent123 is offline Find More Posts by vincent123
RCG Plus Member
Latest blog entry: FZ5: design phase
Reply With Quote
Sign up now
to remove ads between posts
Old Jan 20, 2013, 06:37 AM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
Quote:
Originally Posted by vincent123 View Post
It would be great to have it powered, spread out to land, fold together when speeding!

Looking at your plank design, you work very accurately, nice work.
The powered swing wing is the ultimate aim,I'm in the throes of putting together a prototype centre section to see if I can make the wings move under load.
Thanks for the comments on the plank;some fool once said the camera never lies
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 20, 2013, 10:51 AM
InceCreations
vincent123's Avatar
Joined Jul 2009
732 Posts
You could a pneumatic cilinder instead of a servo, this gives more strength to move the wings.
vincent123 is offline Find More Posts by vincent123
RCG Plus Member
Latest blog entry: FZ5: design phase
Reply With Quote
Old Jan 20, 2013, 11:04 AM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
http://www.rcgroups.com/forums/showt...651923&page=28
This should give some idea of where I'm at with this.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 20, 2013, 12:57 PM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
L/e cut off.This blue foam seems to be a different texture than the pink.Feels"crisper" if that's the right word.Anyway,clean but slow cut,touch more heat next time.
I taped the core edges together before cutting,weighted down flat and tack glued with c/a.I'll set these aside to make sanding templates.t/e next.
Cut done.Probably can't tell from this,but there's about 1mm of bed showing in the middle,the ends are spot on and the cut is dead straight.
Same guides used to mark a channel for the top tow spar.I'm going to attempt to taper the depth of this,using a short length of the spruce to gauge it as I go along with the permagrit,checking the result with the long piece.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 20, 2013, 04:11 PM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
First slot cut,went well.Room at the root end for 8x6k tows.
Then,as a bit of light relief from sanding,thought I'd do some sanding.
Placed some 1/16 x4" sheets over the wing outline.As expected I had to fit a narrow V piece at the root end.The sanding bar made from an old scaling rule is ideal for this.Ample overhang allowed for the curvature.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 21, 2013, 05:04 AM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
I cut the rest of the slots,masked them and laid the tow in.Managed to get it all nice and straight by weighting the ends and brushing away from them.Fiddly job,I can see why Kent uses a tow wetter- outerer thingy.
I've gone with double,ie equivalent to 12k,better safe than sorry.
After the tows were in and thoroughly wet,carefully peeled off the tape,waxed paper and the top bed weighted down.This probably isn't necessary,as the tow seems to be below the surface,but see above.
I'll probably make some more skins up while this goes off.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 21, 2013, 11:02 AM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
All tows in.Not bad for a first attempt.The weights increased from 56g to 65.
I think I'll have a go at working out the servo position next,and some sort of a jig to bore a hole for the con.rod.(bottom hinged,servo buried in the lower surface,horn on top.)
Counter top will be a bit overkill,so a length of mdf window sill is on the shopping list.About 30mm thick iirc.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 21, 2013, 12:34 PM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
I've had a look at various plank designs,I think the servo should be ok here.Straight in,no ext.wires.
While I had the wing set up I checked the canopy/ wing/ fin line.Close to what I planned,the fin should finish just forward of the hinge line,the slope on the canopy plug looks about right to get a nice line onto the top surface.
Frankly I'm amazed this has worked out.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 22, 2013, 01:04 PM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
After a bit of searching I realised the servo wasn't up to the job.I would have liked to have a pair of hs5125s,but a bit out of my budget.So 125s will do for now.If the thing proves it's worth I can treat it to an upgrade.With these being thinner there will be space above to shorten the wires and plug an extension in.
From what I've gleaned over on the slope forum a good start set up will be 7mm on the servo arm and 20mm from the hinge line with the horn.Couldn't find an off the shelf fit,so I picked up a sheet of 1/16 glass to have a go at making some.First attempt isn't bad.Think I'll cut this one in to get the linkage set and if ok make a pair to fit better over the tow.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 24, 2013, 03:19 AM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
Servo fitted.I cut straight through the wing to set the thing as deep as possible.
Waxed plastic sheet betwixt bed and wing,piece of thin glass big enough to come up the sides,another piece in the bottom and a 1/32 piece of ply on top
A mix of epoxy,micro balloons and a touch of graphite for visibility.
The servo and the balsa block I wrapped in two layers of kitchen film.
So,all masked round,a generous amount of epoxy between the layers and on top.
Pressed the servo in and removed excess,every thing weighted down.The open ended (cocktail stick) box stood on the servo with 4 blocks on top.
The result- worked ok,if a little messy.The servo is a nice fit,I need to fix the connecter on the wires and see where I can sit the extension.
Not bad for a first attempt at this kind of install.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 24, 2013, 02:11 PM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
Bit more done.Pair of boards to press the wing sheeting.These I'll cut down to slightly oversize.
Servo,linkage and wires prepared.Not much chance of flex,there's only about 10mm of rod visible.I'll need to keep the slot open while sheeting,a straw with the end capped seems to be the usual way.
I seem to be incapable of following a plan,even my own.I'm going to fit plug in wing tips,should be an interesting exercise.The foil shapes are 2mm lt ply,they'll cover a pair of short carbon tubes epoxied into the wing.The ply will be covered by the wing sheeting.
First flights as is,or a thin balsa cover.Then try different shapes to see what effect they have.One I want to try is the undercut Hoerner type,if I can manage to make a pair.
Last pic is the top side.The first slot I cut was out of line,needs filling.A lot of marks on the foam;masking tape around next time

As you can see,I took these pics standing on my head.Not an easy thing to do.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 25, 2013, 06:47 AM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
Second wing.Trimmed fore and aft as before,ready to cut the first slot.
The first one suffered quite a lot from the dings and arrows of outrageous fumbling,particularly the extremely thin t/e.This one I'm going to leave in the beds as much as possible.To that end I've hinged the beds together along the t/e.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 27, 2013, 05:17 AM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
Bit of progress.The other wing to the same stage as the first.For a change I made a start on the seat.A piece of 1/16 cut to the rear fus.shape less the thickness of a 1/8 strip either side.These shaped from the lower wing bed.Infilled with 1/4&1/16 and sanded.When I got near I glassed the underside to stiffen it up.Not a bad fit,just a bit of fill needed under the nose.
The canopy plug needs a bit more height to get a nice line over the upper surface.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Old Jan 27, 2013, 09:56 AM
I don't like your altitude
Stupot46's Avatar
Joined Sep 2011
3,325 Posts
I made a start on blending the tail in.Removed the short stern post and slotted the wing seat.Still a bit of blending to do down the sides of the fin/fus.
I think the next thing to do is join the wings and get them sheeted.This will give me a better idea of how to bring this part together.
I'm going to join them so the top spar line is flat,so two more pieces of window board needed.
Stupot46 is offline Find More Posts by Stupot46
Reply With Quote
Reply


Thread Tools

Similar Threads
Category Thread Thread Starter Forum Replies Last Post
Discussion "Plank" wings and pendulum stability derp express Modeling Science 30 Mar 02, 2013 07:45 PM
Question Wing tips on a plank Stupot46 Slope 3 Feb 16, 2013 12:10 PM
For Sale Panasonic Lumix LX7 Digital Camera, 10.1MP, Black, Brand New in Box PerlAddict Non R/C Items (FS/W) 3 Feb 05, 2013 03:50 PM
Discussion Straightening a warped balsa plank/wing? C₄H₁₀ The Builders Workshop 8 Jan 07, 2013 12:26 AM