Q5 Low-Wing Sport-Plane - RC Groups
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Mar 07, 2011, 03:29 AM
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Build Log

Q5 Low-Wing Sport-Plane

Hi all, thanks for taking a look at my build log.

I am currently building a low wing sport plan dubbed "Q5"
49" Wing span
34" Length
Estimated AUW: 850 to 950grams
Planed Power plant: Rimfire .10 Prop 10x6

Plans - Dug out ancient drawings and revamped in AutoCAD

Sent out for laser cutting of all major parts will post pics shortly.
Last edited by CADGURU; Mar 15, 2011 at 12:34 PM.
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Mar 07, 2011, 04:02 AM
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will post more pics soon, spend this last Weekend building & organizing the work shop
Last edited by CADGURU; Mar 07, 2011 at 02:03 PM.
Mar 07, 2011, 02:11 PM
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my 24" wing panel that I just finished really twists easily (tip can change in AOA, while holding root, with little effort)

Specs: 1/16 ribs, 1/8 spruce spars top and bottom, 1/16 sheer webs

Maybe should have been 3/16 spar with 1/8 sheer webs.

ANY IDEAS on how to stiffen the wing up in the torsional twist axis?

its plenty strong and stiff in the other axises

I was thinking adding two 1/8 balsa training edge spars (well 1/3 forward from the TE)

or 1/8 by 3/8 webs between ribs (1/3 forward from the TE)

The last scratch build i did was 3 years ago, (1 aircraft) and the others were 10 years ago (3 aircraft)....mostly ARF's in the mean time. and I haven't or don't remember encountering this problem.....will covering help?

I do not plan on sheeting this wing it is an open web. center section is sheeted and the ribs are reduced in size to accommodate.
Mar 07, 2011, 03:25 PM
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As long as it is straight when not twisted by hand, the covering will give it torsional stiffness. I am mainly a scratch builder and do it a lot with the lightweight designs. Remember, building lightweight thermal gliders the wing will twist a lot before covering, but after covering it is amazing how much strength is added.
Do you have a picture of what the final outcome of the model should be?
Mar 07, 2011, 05:58 PM
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Thanks for the words of encouragement I can post a side view from the plans, But its just your typical low wing sport plan. Like a low wing version of an Edge 540 or Extra 300
Mar 08, 2011, 11:30 PM
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Do you mind sharing who did the laser cutting for you, and what the cost was? Just curious.

Thanks! Mickydee
Mar 09, 2011, 01:45 AM
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Laser Cutting:

Two companies did the laser cutting:

AKM Laser cutting -- http://ak-models.com/lasercutservices.htm -- Cost was about $50.00 with materials included - could have been less if I had done more Lite-Ply, Birch ply is expensive. Shipping costs were about $15


Trinity River Studios, a new company local to me here in Texas, also re-cut some parts because I made some changes. They just got their laser, and I have been working with them to setup cutting services for aircraft modelers.
So it didn't cost me anything.

The photos are from Trinity River Studios cuts.

AKM has a 42" Laser and TRS has a 24" Laser.

AKM also has Lite-Ply and Birch-Ply and Balsa in stock to cut from.

I ended up with nearly to complete parts set. I will be building a second plane with even more updates as soon as this one is off the building table and maiden'ed/Test Flown.
Last edited by CADGURU; Mar 14, 2011 at 01:41 AM.
Mar 09, 2011, 02:17 AM
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Latest Update

Hi all After getting some great help from the forums I finished the first wing panel
panel. The cross bracing from TE to Spar really help stiffen up the wing for torsional forces, with covering I think it should be solid as a rock, I don't think
there is a chance covering will warp it out of whack. I built in 2 degrees washout into the design so the wing no warping is a good thing

Installed the tray for my wing servo, and the servo wire tubes temporary.
Fat straws from the local gas station will fit Futaba micro plugs. I plan on using
using servos with micro plugs and extension lead and an adapter lead. This way I can run the wires through these particular tubes. Sound complex, but I already have my Receiver that uses standard J plugs.
Last edited by CADGURU; Mar 13, 2011 at 01:11 AM.
Mar 09, 2011, 02:25 AM
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Made some Gussets to brace where the 1/8 Cross bracing comes together on the fuselage. Made these from scraps of 3/32 birch ply. Had some square punch outs, from the laser cutting. I just cut off the corners and glued them on.

Also made some dowels for the fuselage, Test fit both fuselage halves with all the formers and dowels other parts. Lacking a jig, I was testing some ways of building the fuselage upside down on the plan while keeping everything straight.
Last edited by CADGURU; Mar 13, 2011 at 01:10 AM.
Mar 11, 2011, 01:26 AM
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Fuselage in my new Jig

I managed to get the fuselage in my new jig:

I decided building one was the fastest and almost cheapest route to take.
You can see my Mini-How-To on building this jig here:

Hopefully everything comes out straight and square and plumb for once!
Mar 15, 2011, 01:12 AM
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My Dog Eats my new Sanding Belts

I was reading one of the "must have" tools was a disc sander. I read this could also be use for shaping parts using the "plans stick on method; ala 3M 77". I Having been struggling with getting parts and stick ends sanded square and true; So, I bought a combination disc / belt sander today a small bench top unit and some extra belts & discs.

Upon returning home, I had some chores to do and I left the plastic bag containing the belts on the floor and proceeded with my chores.

Unbeknownst to me while performing my menial tasks my 16 year old Westie Terrier was hard at work ravaging the contents of my shopping bag. I returned from outside to finder her chomping on one new of the Sanding belts. She had already chewed in half and put teeth marks on 50 % of the rest of it. She did not want to give it up either.

Animal fat based glue? pig skin based belt? A smell and texture too hard to resist, definitely!

May all who own such a piece of equipment be advised: keep your sanding belts high in your shop far from your pets reach. Espeically if they are the cheap .79 cent ones from a cheap tool supplier
Mar 15, 2011, 03:11 AM
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More Building Photos

Over the weekend, I manged to get my Vertical Stabilizer and Rudder built.

I also got my Horizontal stabilizer and elevator built.

These are built from 1/4" Sticks and 1/4" Sheet parts. The are quite strong and very light weight.

I sanded them down and shaped the leading edges and trailing edges with my handy Great Planes shaper tool.
Mar 15, 2011, 03:22 AM
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Building the Turtle Deck

I use my jig again to build the back end of the fuselage and Turtle Deck.

Had a slight error with F8 (I will have to check my laser templates to see what up) For some reason it was way too tall, So I cut it down and glued it back together and added a little reinforcement to the back side.

The reset of the Turtle Deck went smooth. I have been Hemming and Hawing over if I should have used 1/8" sticks instead of 1/16". The backbone is 1/8" by 1/4" so I should be ok. The slots in the formers were a tight fit for 1/8" but could have accommodated.

I'm not sure how I am going to finish off the Turtle Deck past the Horizontal stabilizer along the vertical stab. Maybe some shaped foam or shaped balsa blocks, if they are not too heavy.
Last edited by CADGURU; Mar 15, 2011 at 03:34 AM.

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