Dereck Woodward Bigga Bit

[Piers Bowlan]

Mine flew with the babe bee, it flew like holding a tiger by the tale until the fuel ran out. Yes I fitted the .074 Queen Bee but got involved in another project before I had a chance to fly it unfortunately.

I did exactly the same as Dick as far as achieving the rear fuselage shape.

Edited By Piers Bowlan on 08/01/2020 16:07:09

[Bob Cotsford]

Yep, score, crack and soak in glue for the sharp bend. There's no reason why you shouldn't curve the sides if that's what you prefer and you have room inside for whatever bits you're putting in the fus. I'm guessing that the parallel sided fuselage was to accomodate the old full size servos.

[Ken Lighten]

Posted by Nigel R on 07/01/2020 22:25:07:

Biggest bit ?

Sounds ace!

Sure was, tempted to make another one now!

[Paul Marsh]

I built one years ago, still have it and its flown quite a bit over the 20 years. Has a OS 25FP.

[Nigel R]

Nice and bright!

I'm half tempted to fit a glow in the front

I made some foamboard tips and elevens. Both are edged with 3/16.

They're stiff enough but the foamboard isn't that tidy. I'm not sure I'll use it again. It would have been quicker to cut from sheet balsa.

[Nigel R]

Thanks for thoughts on the rear fuselage.

I feel unsure the 3mm liteply will crack and bend quite as easily as balsa would. The other thought that occurred is that the rear fuselage probably doesn't need to be a slab of liteply for strength, and it is weight in the wrong place, so I'd probably be looking at cutting big holes in it. The front section probably does need a bit of ply type stuff - it is mopping up any and all reinforcement needed for firewall, U/C, wing bolts/pegs and servo mounts.

Having looked at the Bubbles plan on Outerzone it seems DW used two separate sections, the usual front parallel box, and the rear taper part, simply glued together with some reinforcement around the joint. If I did that I could just use some 3/32 to make the rear sides. Hmm...

[Bob Cotsford]

For liteply saw 3/4 of the way through with a hacksaw blade, fill the sawcut with PVA or epoxy glue and bend the side to shape. Actually it might be as easy to make the fuselage in two parts, the straight front and the tapered rear, and just glue them together. There's no great load on the rear fuselage as it's so short.

[Trevor]

Why not use balsa for the sides, with 1/32 ply doublers on the inside. By cutting strategically placed holes in the doublers, you can get the strength where you want it while still having flexibility towards the rear.

Trevor

[Nigel R]

It would work. I'm a bit short on appropriate materials though.

[Piers Bowlan]

Why not just make conventionally curved sides like Bob's 'late lamented Little Bit' , there is no law to say the fuselage has to have angular sections to retain it's character or flying qualities, or is that too radical?

(I have just dragged my LB out of retirement )

[Nigel R]

Too many choices!

So tonight's session got this far:

[Nigel R]

Which is not too far off done.

The foamboard ribs tidy up well enough with some cap strips

[Nigel R]

Servo install is as basic as it gets. A couple of bits of ply level with the rib edges.

[Nigel R]

So jobs to do. Leading edge needs some shape. Tips need attaching. That's about it before moving on to the fuselage.

[Nigel R]

[Nigel R]

Rounded the LE and moved into the fuselage.

I found a set of stand offs for a 3536 type motor ready cut so I'm going to use one of those. I drilled some likely looking holes in the firewall for them and the battery leads.

Wing peg hole drilled in f2 along with a nice big hole to poke the lipo through.

Decided in making the rear end from balsa to keep the weight down so the liteply sides are just 13" long.

[Nigel R]

Spot the mistake. ..

[Piers Bowlan]

Balsa rear fuselage pieces up side down - won’t make any difference to how it flies.🙂

[Dickw]

At least you don't have to worry about tailplane incidence so, as Piers says, it will still fly OK.

Dick

[Nigel R]

Straight to the top of the class Piers - very eagle eyed!

How I did that I'm not sure. It was in and out the jig a number of times while fitting the rear pieces, and every time I put it in upside down without noticing.

Dick, yes, it would fly perfectly well like that. Nevertheless. I cracked the joint and remade it the right way around as soon as I had noticed. However after re-glueing, I wasn't 100% happy with the resultant joint and I figured it would need some reinforcement.

The rear sides were stuck on, essentially, with an end grain joint (which was a good joint the first time around, and sadly less so the second), reinforced with some 1/4" sq (ish) stuffed into the corner between the former and the balsa side. Most of the strength in that arrangement was coming across the cross grain of that corner reinforcement. Not really enough in my book.

I came up with this:

Those are biscuit joints, give or take.

(note, this shows the mess I made of the end of the liteply sides while cutting the back off, a definite black mark for me, especially after I made a nice neat job of the joints the first time around)

I made the slots using a dremel with three of those 1" diameter circular saw blades stacked together. This makes a neat slot to hold a biscuit of 1/32" ply. A good dose of thin cyano on the outside and inside, and that isn't going anywhere now. Actually very quick to make.

I wonder if they might have some application reinforcing firewall joints?

As an aside to the above, I've noted 13 hours getting the woodwork together, so far. 

Edited By Nigel R on 14/01/2020 10:45:25

Edited By Nigel R on 14/01/2020 10:49:18

[Piers Bowlan]

One of the great things about balsa wood as a model aircraft building material is that it is so versatile if the build doesn't go quite to plan. Cut out and rebuild, it will all gets covered in film anyway so no one will see. Only ones pride is damaged!

Good idea about using that technique for reinforcing firewall joints .

[Nigel R]

It is great stuff Piers. As you say, if you make a mistake, it doesn't matter to much, it is just wood, it can be fixed.

I find it quite thereapeutic to work with wood. A natural material. Requires concentration, an amount of detachment from the outside world, gives a sense of achievement. All good for the soul. As a bonus, our lightweight woods require only a fairly modest toolset compared to tougher timbers.

 

Edited By Nigel R on 14/01/2020 13:56:41

[Nigel R]

[Stephen Jones]

I built one of them many moons ago.

But i used the wings of a ugly stick ( barn stormer 25 ) as they where the same.

I remember fitting a false tailplane with sticky tape and a length of string so it would go along the ground looking normal until the string pulled the tailplane of so it looked as though my tailplane had come of .

The looks i got as it flew around the skies without its tailplane.

Steve

[Nigel R]

I like your style Steve ☺

This design is spiritually an ugly stik with no tail. I'm sure Dereck would have approved (especially of the fake tailplane)

Above photo shows I have decided to fit a UC of some sort to keep the prop out of the dirt. It will probably be a torque arm type from 8 or 10 swg. I say probably as it will be the first thing I have to buy for this build!