Building the Whizzza.

[Mike S]

Well I can't put it off any more so here we go. Twenty years of demons clawing at me since the final flight of my Hi-boy and its spiral dive of death.

Here is a photo of the finished Whizzza.

      

So with plan laid out, the balsa pile begging to be hammered in to a flyable machine I started thinking about the journey ahead. Will it build easy with no headaches or is this the stuff of dreamless nights and cold sweats. ( sorry just had to build it up )

This is what was used to build this from plan to plane.

Spec's:

Motor: JP EnErg C35-14 1100kv 600watt
Prop Size       Amps   Thrust   Power (W)   RPM Volts
APC (11x5.5)  32.3    1290g    327           9200    11.1V   My chosen set up.
APC (12x6)     38.6    1425g    386           8400   11.1V
APC (11x7)     36.0    1200g    343           8500   11.1V
APC (13x6.5)   44.7    1502g    427          7300    11.1V
APC (9x7.5)    42.5     1210g    544          11000  14.8V
APC (9x6)       35.1     1310g    468         12400   14.8V

ESC: JP EnErg PRO 50 SBEC ESC (50A) (2-6 CELLS)

Continuous - 50A (Maximum 10 seconds @ Burst - 70A)
Weight - 32g
Size - 23x52x7mm
Lipo Cells - 2-6 (NiMH Cells - 5-18)
BEC Output - 5.5V/4A
Programmable - Yes (Manually or by Program card not included)

Servos: 3 x Futaba 148S

1 x Aileron
1 x Rudder
1 x Elevator

Controls: Sullivan Snakes 508

1 x Rudder
1 x Elevator

Controls: Metal control rod and carbon rods for Ailerons

Lipos: 2 x Overlander 3s 2200 mah 1 x Turnigy 3s 2200 mah Flight time around 5 - 8 minutes depending on throttle use & weather conditions. A 3200 mah pack may help to reduce the added nose weight and increase the flight time.

Covering: Pro film White and Yellow, Solarfilm Red  The original plan was white fuse , tail & rudder and yellow main wing. 1M yellow is not enough to cover the main wing so what ever colour you choose I would suggest  the following size to cover like mine

1m of White   for fuse/rudder/stabilizer/ailerons
1m of yellow   fornose/main wing/ailerons
1m of red       for fuse/main wing

If you wish to cover in separate colours then I would suggest using these sizes:

1M of chosen colour for fuse/rudder/stabilizer.
2m of chosen colour for main wings and ailerons.

Prop: APC 11 x 5.5 with a aluminum 2" spinner

Landing gear: Carbon main gear and carbon tail skid from carbon copy.

Rx: Spektrum Ar500. Due to problems in another model with another AR500 that led to a crash I am going to replace this and the other model with AR7000's

Wood: Balsa sizes This a guide so check with the plan first

(5mm x 76 x 915mm)  sheet soft to medium fuse sides/doubler's x 3
(5mm x 76 x 915mm)  sheet medium for fin and rudder/tail wing x 1
4mm square dowel 100cm x1 for stabilizer/rudder Le x1

(6mm x 76 x 915mm)  sheet medium fuse bottom x 1
(10mm x 76 x 915mm)  sheet soft balsa fuse top x 1
Triangle     6mm x 6mm x 915mm

Wing
(12mm x 100 x 915mm)  medium to soft 36" long x 2
(12mm x 100 x 915mm)  medium to soft ailerons x 1 or use pre-cut aileron as I did
spruce bar  10mm x 3mm 100 cm x 1  (3.2mmx9.5mm)
4mm square dowel 100cm x 1

So here is a video of a very well built Whizzza. This shows how well the model flys and what you can expect to do with it.

                             

Whizzza

   

 
When we brought the balsa we decided to build the horizontal stabilizer as one piece with a square hard dowel leading edge rather than using two pieces one of med and one of firm as per the plan.




To start with I used two plans one for cutting and one a master copy. I cut each template I needed out of the second plan and used the first for reference.

I laid each template on the balsa to try and have as little waist as possible. I will admit I did forget about the grain direction but as it turns out I got lucky. (thanks to Gareth for point this out).



I cut each piece with 2mm excess balsa so I could sand level unless the edge is already level Ie if you are using the sheet edge as part of the build.

Once the rough balsa parts had been cut out I dry fitted them together and laid the templates on top.



I found that my cuts where ok-ish and little sanding was need to true up the edges so I set about glue the main section of the stab to the stab edges. Now as I am going to glue the square dowel on the LE I also had to allow a little extra length to the stab tips as you'll see from the next photo.



The elevators need a short piece of square dowel as per the plan. I extended mine a little by 2cm to give extra support.



At the same time I also cut out the square dowel LE's and cut in the small open area needed to fit the fuse. This may need adjusting when fitting to the fuse latter on.



Now I glued the dowels in to place and secured with masking tape and placed a heavy book to keep level while drying for 12hrs approx.  I am using Aliphatic resin by Deluxe Materials.

The stabilizer is ready to sand and once this is done I may cover it and hinge the elevator before moving on to the tail.

[Mike S]

I have finished chamfering the Le, tips and Elevator so this will now be put aside.

Rudder and Fin.

I again cut out the template for this and then cut off the rubber. Again checking the grain direction I marked out the rudder with the template allowing 2mm around the edges to be sanded.

Here is the rough cut


And after sanding.


Same thing with the fin but whats not shown on the plan is the fin glues to the stab surface so when cutting you can the see the stab side on in the template so use this to how far to cut.

Here's the template with the fin marked showing the shape the.


Here's the rough Fin


I decided to add square dowel to the lead edge of the fin and also further angle to the fin shown in the picture.


Here's the finished rudder and now glued fin waiting for sanding.


Final fin and rudder finished.


I decided to cover the fin and rudder to get a idea of how the covering handles and along with the iron I brought for the job. I am using mylar hinges and have fitted them. I will need to remove some of the covering when it comes to attaching the fin to the stab. 

[Russ]

Watching with interest Mike. 

At the rate your going, looks like you'll be finished in a couple of weeks.

I know both you and Gareth went shopping for all the wood; where did you purchase it from?

[Mike S]

Fingers crossed russ I might get it finished. Brought the wood from WLM along with the covering white and yellow, snakes, carbon contol rods, Ar500 etc.

Motor and esc came from brc.

should get around 160watts per pound on a 3s with the 3514 jp motor

[Mike S]

Main wing.

Decided to tackle the main wing now I have got used to the knife and how the balsa cuts and how to sand it with the perma-grit bar.

So first thing again is to cut out the wing template and cut it down to the following:

Main wing section
Front wing section
Wing tips
Ailerons
Front square dowel.

So started of with front wing section. As the balsa is 10mm think I thought I can either razor saw it or use the scalpel. I decided on the Scalpel and gave my self the 2mm extra balsa just in case the cut went wrong.

Wing front starboard wing


Cut went well so I sanded of the spare and checked the template. Remember you create the wing from the whole sheet so do not cut the sheet in half. To the create the second half front I just lift the template at the tip and laid it down the other side upside down so mirroring the other half. Mark it and cut. Good thing I allowed a little extra as Ben my cat jumped on the table and knocked the ruler I was using to guide the knife and it cut in wards a little. Sanded back all is good.

Wing front section


Dry fit of the parts

At this point I noticed that the aileron has a warp to it hmm sure this was not there at the shop and it's slightly to small. Oh well we guessed it as I left the plan at home.

!!Update!!

I picked up a new aileron piece from WLM yesterday with the plan this time . Its slightly deeper in width so will need a little removing to bring it line with the wing.




Next I used the dowel template and cut the dowel to size and glued it on the front both sides



Decide to fit the main spar. The plan suggests fitting a 6" main spruce spar in between the front and main section with balsa spar from the to the tip. We decided to fit spruce from tip to tip as to give full support in the wing.



Wing tips

With the template laid and Ben's approval I marked the balsa to be cut.



I cut the second the wing tip out and laid them on top of each other. With a 2mm allowance
around the markings I taped them together and sanded them both at the same time until both the wing tips became level. I did this for all sides and the checked the template on both tips.

Ready for sanding


Ready for fitting.

[Gareth]

Looking good mike  if it goes like either of mine you will be very happy with this model.

Seems like you are making good progress through the build, its a rewarding model to build and to fly, you will love it.

Gareth

[Mike S]

My original plan was to cover the main wings, aileron, stab and elevator with yellow. I have now decided to cover the control surface with white to match the fuse an have yellow wings.

So here is the stab covered in yellow, now you'll have to forgive me on this as it's been twenty years since I covered a plane in yellow and I hated ever minute of it, I was eight at the time.

I found covering the fin and rudder enjoyable, however the stab brought back the nightmares I can remember from covering the Hi-Boy & Fly-Boy. Well twenty odd years on and with the internet to hand a little video watching was the order of the day. (no not that type of video ).

So here's the result I have covered the stab.



So now that I am covering the elevator in white I went ahead and covered it.



At the is point a little break was in order as I had run out if tea & biscuits.

Ok so time to fit the mylar hinges. The plan does not indicate how many hinges or locations so your on own here on all the control surfaces. I decided to fit four hinges, two ether side of the square dowel. I fitted them the same way as I did the fin and rudder. I measured out the distance from the centre of the stab to the wing tap and measured equal marks for the hinges. Using a scalpel I made a little cut just larger than the hinges themselves in each of the four locations.

I marked the centre of each hinge and inserted a T-pin to aid centering once in the stab.



With the hinges in place in the stab I taped the elevator in place and using the hinges themselves marked the locations on elevator. With a little work I fitted the elevator and centred the hinges, next I adjusted the elevator so it had equal gaps either end and gave it a few movements to let it finds its own place.



Now i just had to remove the pins. I not going to glue them yet.

A rough I idea of how it will look.



Until the fuse is built that's it for them as I need add infill to support the tail but will not know that until I put the stab & fin on the fuse.

[Gareth]

Looks nice Mike, Yellow and White seem quite popular with AcroWots so should show up well.

Just a note, based upon the kit i built, you might need to shape the vertical stab at the front to fit the fuz, you could slot the fuz to take the tail as well.

The one i built, the bottom tail was flat against the horizontal stab, where the stab opens up there was a vertical cut up and then a diagonal so the tail sits on the top of the rear decking (matching the angle). Either way will work just thought i would point out how mine was done if it might make it easier.

Gareth

[Mike S]

I remember you saying about this so I thought I might as well have a go at covering as I know some of it will need to come off the be cut and glued.

Back to work tomorrow so no more building for a few days unless I can get a few hours in after work.

I have got the main wings built with the tips glued on. Its at the stage where it needs the spruce sanding, profile sanded in and the ailerons cut and fitted.

I will pick up another aileron piece in the week and will make start on the fuse next. I will have to decided if I am going to add a few mm's to the fuse width to fit the motor and decided on the u/c fitting.

With a few days at work I can work these things out.

[Mike S]

!!Update!!.

Just checking the main wing and looks like I may have retry this build. Not sure how this happened but there is a bit of a bow to the Le on the startbard wing. I checked this before gluing the dowel with the ruler edge!!!!. Also the port wing wing is 2mm thinner than the startboard again I measured this but I made a mistake somewhere.

The main problem is moment is the starboard wing will create a little more lift and will be heavier up setting the laterial balance.

Gareth I will bring it with me.

[Mike S]

!!Update2!!

Well Gareth went over the wing  with as much detail as his fantastic doggy did with my leg . Randy bugger.

Seems the wing is fine, I knew I had measured everything correctly but I could not work how I had make the mistake. The mistake was that I misaligned the port tip by around 2 odd mm's. No warp to in the wing and the wings are infact the same width.

So Gareth suggested remove the tip a few mm's past the wing end and sand the wing back to level. Cut out new tip and attach correctly .

[Russ]

Covering job looks good Mike. What type of film are you using?

[Mike S]

Flattery gets you everywhere Russ. My corners need work but for now I am re-learning.

I can't remember the name of the covering but it was from WLM at 7.99 a roll.

I have a look when I get home unless Gareth can remember and post's up the name.

[Mike S]

Russ its pro-film. I had a look just now as I was in the shop.

[Mike S]

Ok as the Mrs has gone to slimming world then out with the girls for a Chinese yep I know.

Anyhow I have some time to spare so here we go with the fuselage . Now I know I need two halves for the fuse but had to think about how I was going to achieve this from two sheets of balsa and end up with two perfect mirrored halves.

The thought was I would the use the idea I used on the wing tips. I cut out the fuse template then broke this down in to:

Main one piece section,
Top rear section,
Canopy,
Front top section
Bottom section panels.
Tail filler

So taking the one piece main section I laid this down on the balsa sheet with the top of the template level with the top of the sheet. My theory here was if the sheet is straight which I checked it was I would have nice level sections for the stab and main wings.



Once I had one section I laid the rough cut section on top of the second sheet and cut out the next half. Now there maybe a easy better way than this but for now this is all I can think of.

Gareth showed me a way to stop the ruler from moving when cutting the balsa by using pins to secure the ruler by putting pins around the ruler opposite edge of the side you are cutting. This works a treat.

So next I taped the two halves together and put some T-pins in to secure them from moving. I stuck the template on and using the template I squared up the edges with the perma-grit and sanded back to the mark lines.



To make the rear top triangular panels I again used the same method to end up with two mirrored parts.



So thats it for tonight. My daughter who is the art & craft person in the house cut out the mid-section A frame but that needs sanding to profile tomorrow.

Last pic for today is of the two fuse sections main and top rear.