More sticks! Frank's Guillows Arrow RC.... Covid build

[Frank v B]

Tail feathers:

Fin/rudder- The shape stayed the same, the fin bottoms were left long so I can secure it better.  Note that all balsa strips are left long and are easier to trim afterwards.

Stabilizer/elevator- this is a lifting stab (airfoiled).  I used the original outline of the entire stab then put in a double piece of balsa to create the hinge line.  All ribs were notched over the new wood and glued.  A "V" was built into the center of the elevator to allow the rudder to clear it.  Again, all edges will be trimmed after the stab dries.  When dry, I will have to fill in the trailing edge of the stab and leading edge of the elevator to fill in between the ribs.

Photo 76- all circular cut tip parts for the wing, stab and rudder were coated with glue on the inside and outside of the balsa piece.  Wood always splits along the grain.  This strengthens the wood.  I used carpenters glue and a toothpick.

Photo 77- the stab before the spars are added.

Photo 78- The fin and rudder.

Frank

[Frank v B]

Bending the wingtip part of the polyhedral wing.  The leading and trailing edges were pre-cut at this "break".  Removed the pins, lifted up the tip to the height of the pre-cut stick and glued the joint.  Both sides.

Frank

[Frank v B]

Setting the main polyhedral break.

Photo 83- removed the center rib, put glue between the joints in the leading edge, trailing edge and the scissored two top spars and then re-assembled.
Photo 84- set the midwing break using the brace.  Put a pin in the leading edge and trailing edge to keep the joint together.


Frank

[pmackenzie]

Had this kit for a while, you inspired me to start on it
Started this morning, here is how far I have it.

Mine will be be rubber powered.
Hopefully I can get it trimmed well enough to lose it at some point (but not too soon).

Pretty sure it was a Toldeo swap shop buy.

I have quite a few FF kits in my "one of these days" pile. Rubber was always one of my favorite model types, so long overdue to get some of them built.


Pat MacKenzie

[Frank v B]

Pat,

Good for you! 
The main difference between yours and mine... yours will be a work of art. .  Mine will observe the 50/10 rule*.

Building this kit was a total recall of the first stick and tissue rubber band plane I built when I was in grade 3.  It was a Veron kit and it flew all of 15'...but that was magic and as good as a mile.

Frank

* looks fine at 50 feet and 10 km/h.  If it makes it to 50 km/h...it will be self-shredding.

[Frank v B]

Stab and Fin/rudder

- Cut them apart (elevator from stabilizer, rudder from fin) and sanded them.
- trimmed the ribs flush with the trailing edge
- built up the trailing edge of the stab and leading edge of the elevator.

Photo 85- shows stab and elevator separated with the leading and trailing edges built up and pinned while the glue dries.
Photo 86- Fin and rudder completed.

Frank

[Frank v B]

Sanded the wing and tail feathers.  Even with careful sanding, a leading edge and a trailing edge glue joint failed at outboard dihedral breaks.

DA FIX:
Watered down a little carpenters glue, brushed it on the bottom of each of the trailing and leading edge breaks, put on a few strands of kevlar and put waxed paper on top to flatten them out.  All 6 of them.

The kevlar strands are as fine as silk and the same colour as the glue.

If this plane ever goes into a dive, it will be 6 joints flying in formation as the wing shreds in between them.


Frank

[pmackenzie]

Some more pics of my progress, starting to look like a plane

I had trouble with the rear turtle desk formers, they were simply not the correct width to fit where the plans show. 
The fuzzy image shows how distorted the rear part of the fuse was with them installed. So I removed them, completed the fuse with cross braces and then made new ones.
Looks much better now.

It  looks to me like the card-stock fill pieces they call for above the wing won't work properly, the cut out is too deep so it needs to be one piece.
Not sure how I am going to tackle that yet, perhaps mould some 1/32 balsa to the same curve as the fuse,  and carefully trim it till it fits the wing?
Same thing for the cockpit cut-out would be nicer that card-stock.

Also thinking of adding a pop-up DT. That would let me adjust stab incidence and tilt, which is often necessary to get proper trim between power on and power off.
The plans show some details for the glow conversion, but I would do it slightly different.

Pat MacKenzie

[Frank v B]

Looks great Pat. I will make the bent stuff out of 1/32 balsa.  Cardboard shouldn't be on a balsa model.  :-)

Found a small motor.  Will start on the light end.  Otherwise I will switch to an E-Flite 180.  A great little motor.

The covering is next.

Frank

[pmackenzie]

That looks like ether the HK 10 gram, or perhaps 5 gram motor?
If the former, it will have plenty of power for this size/weight model.

[Frank v B]

It's probably the 5 gram.  I took a photo of the 15 gram one (was still in the package) next to the one on the plane.  I googled Hextronic 5 gram and it looks like the one. 
Thanks for the ID.  The stats show it as a 2 amp max on 2 cells a whopping 15 watts.
Both motors came from a good friend who exited the hobby. 

It is easy enough to change and upgrade at any time.

Frank

[GuyOReilly]

Looking forward to seeing this stick-project covered and painted.
Great looking plane!
Guy

[pmackenzie]

Things are slowing down now, it takes me a lot of time to decide on things

Started working on the 1/32 balsa parts for the fill over the wing and the cockpit cut out.
First step was to form some stock over a 1.25" aluminum tube:
   - soak the parts
   - bend around the tube and wrap with tensor bandage
   - put in the oven on low for about 1 hour. (This could be skipped and just left to dry overnight)

First picture shows the result.

Then start cutting the parts to length and width till they fit where they belong.
Second picture shows the cockpit part in place and glued up, over-wing one is just sitting in place.
I will cut the cockpit opening after the glue has dried.

Fitting the wing fairing will be tricky, sneaking up on the final shapes.  I think I will add some centre sheeting to the wing to make it easier.
I estimate about 1/2 gram additional weight, but the final result will be much nicer than just gluing it to the tissue. Plus I can use a bit of filler if I have to
Sheeting will be about 1/2 a rib bay either side of the centre, so I will also have to add ribs on each end of it.

If mine were an R/C conversion where the 1/2 gram would be irrelevant I would not hesitate to add the sheeting 
I will save the 1/2 gram somewhere else, lighter wheels and/or prop for example.

Pat MacKenzie

[Frank v B]

Took your advice Pat and sheeted the center section with 1/32.   I did 2 complete bays, one each side of the center rib. A half bay looked too silly and a bit like building a bridge halfway across a river.
Did the cockpit in 1/32 balsa.

Photo 92- the cockpit
Photo 93- the wing center section (top only).  I had already covered the bottom before dinner.

Frank

[Frank v B]

Next problem- the tail feathers.

How do you attach a fin to a stab when it is just supposed to be glued on top of a rib?

What is missing is both a secure anchor point and a flat spot to attach the stab covering to at the base of the fin.

I slotted two pieces of 1/16 balsa where the two top spars are located, slipped the wood up from the bottom and glued them to either side of the centre rib.  This created a 1/16" high slot into which the fin slips.  It also allows the covering to be fastened to these false ribs.

If I were to do it over again, I would have installed two centre ribs, 1/16" apart and extended the bottom of the fin with slots for the two spars.  Oh well.

Photo 95- The two pieces of wood attached to the centre rib
Photo 96- The slot sanded and the fin adjusted.
Photo 97- the fin held in the slot (no glue yet).

Will cover all the parts separately and then assemble once everything is hinged.

Frank