DW Tiger Moth 0.8M Balsa ARF Nitro conversion

[tudordewolf]

'Tis the season to build, with 30mph winds and 20 degree weather on the forecast.

Another Dancing Wings kit, this brand is growing on me for its value and interesting offerings. A pre-built, pre-covered balsa ARF, something of a rarity in 2025 and available from amain.

It's a gorgeous kit. All-wood structure, a few strategically placed carbon fiber rods, and a bright, well-applied covering. Even the ailerons are built-up profiles rather than flat boards, which is impressive at this smaller scale.

I'm building it to take a Thunder Tiger GP-7, a neat little 1.14cc engine with big-engine features like a throttled carburetor and piped exhaust for a clean(-ish) plane. I grabbed a muffler extension for it which will help it clear the cowling, making it an extra-unique configuration since that's a GP-7 specific accessory.

An SH-7 would also fit the bill, which has the added advantage of being slightly more powerful, probably owing to being a ball-bearing engine rather than the GP's plain bearing.

To fit the engine instead of a motor I needed to move the firewall back nearly an inch, aided by a miniature saw:

A 2oz round tank from Sullivan fits with not even a millimeter to spare and then a little more sanded out across the top, which should give me a 10-minute flight time, and I glued in a few stringers to support a throttle servo and a "platform" for the receiver::

 

[Tunedfrog]

Awesome plane. I'm on my second one this year. Allmost done with it.

 

[CertifiedMike]

'Tis the season to build, with 30mph winds and 20 degree weather on the forecast.

Another Dancing Wings kit, this brand is growing on me for its value and interesting offerings. A pre-built, pre-covered balsa ARF, something of a rarity in 2025 and available from amain.

It's a gorgeous kit. All-wood structure, a few strategically placed carbon fiber rods, and a bright, well-applied covering. Even the ailerons are built-up profiles rather than flat boards, which is impressive at this smaller scale.

View attachment 223365View attachment 223379View attachment 223378

I'm building it to take a Thunder Tiger GP-7, a neat little 1.14cc engine with big-engine features like a throttled carburetor and piped exhaust for a clean(-ish) plane. I grabbed a muffler extension for it which will help it clear the cowling, making it an extra-unique configuration since that's a GP-7 specific accessory.

View attachment 223388

An SH-7 would also fit the bill, which has the added advantage of being slightly more powerful, probably owing to being a ball-bearing engine rather than the GP's plain bearing.

To fit the engine instead of a motor I needed to move the firewall back nearly an inch, aided by a miniature saw:
View attachment 223366View attachment 223367
A 2oz round tank from Sullivan fits with not even a millimeter to spare and then a little more sanded out across the top, which should give me a 10-minute flight time, and I glued in a few stringers to support a throttle servo and a "platform" for the receiver::
View attachment 223368View attachment 223369

Your addiction to rc is different than mine but equally as twisted!!! I love the nitro idea!!!
This looks like a beautiful plane!
I love the yellow! I might be able to follow it in the sky!

 

[fstnd]

Nitro RC planes look wayy too attractive... it's just a shame that there's literally NO SPACE to fly one Probably why they're so cheap in my area
I like your nitro ideaas well

 

[Hobbydude2]

Nitro RC planes look wayy too attractive... it's just a shame that there's literally NO SPACE to fly one Probably why they're so cheap in my area
I like your nitro ideaas well

You just have to hit the road and find a huge field.

 

[tudordewolf]

Put together a little break-in stand for the GP-7:

Waiting on a 6x3 prop to do the break in exactly according the the manual, and then will fly it with the 7x3 pictured if all goes well.

Had to 3D print a centering ring for the 7x3 since that engine has an unusual M4 crank thread. I dialed in prototypes till I had a tight fit both in the prop and over the crank.

 

[tudordewolf]

Did the break-in, couldn't be happier with how nicely this engine runs. It started right up and never stalled on the starting needle settings, throttling up and down without bogging, then leaned out easily and produced good RPM numbers even richened up a quarter turn.

I ran it on Brodak's "1/2A Fuel," 25% nitro, with a nice thick 22% oil blend of 50/50 synthetic and castor, which I chose for the engine's plain bearing design and reputation for needing higher nitro. I used an OS #7 glow plug and it never stalled out on me.

Some of the previous forum posts I've read about it gave mixed opinions, but I'm impressed. It turns a 6x3 at 17k RPM, and a 7x3 at 12.5k, interestingly both produced ~1lb of static thrust, in fact according to this calculator, they produced *exactly* the same static thrust, though that's only an estimate. Since it's going on a biplane, I'm not too worried about the lower pitch speed of the 7x3, the look and sound will be much more suitable, plus, lucky 7's! GP-7 engine, #7 glow plug, 7" propeller.

 

[tudordewolf]

Got the front covered and the engine mounted, things are coming together... Made the windscreens from a plastic bottle as the were absent from the box.

 

[CertifiedMike]

Got the front covered and the engine mounted, things are coming together... Made the windscreens from a plastic bottle as the were absent from the box.


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The 'bottles' look like they came from the kit!
Its coming together nicely! Great job!

 

[tudordewolf]

Got the top wing fitted and rigged, the bracing wires were tricky but satisfying once finished:

 

[Hobbydude2]

Looking great.

 

[tudordewolf]

Looking great.

Thank you!

First & second flights successful!

The covering really pops in the sun:

 

[tudordewolf]

Some more little details - made a tiny air filter, moved the pressure tap to the other side of the pipe, and detail of the bespoke muffler extension -

 

[CertifiedMike]

Some more little details - made a tiny air filter, moved the pressure tap to the other side of the pipe, and detail of the bespoke muffler extension -

View attachment 232153

View attachment 232154

Beautiful!

 

[tudordewolf]

Aaaand I backed over it in my driveway while in a hurry to take it to the field.

Engine survived, so I did a complete rebuild with improvements, mainly servos moved into the fuselage to further improve CG.

Made up a servo tray for 4.3g servos:

Filled in and covered the old servo mount in the tail with a balsa block supporting pushrod guides, made from nylon tube, supporting carbon fiber rods weighing less than a gram apiece:

The rebuild has since flown with its other nitro bretheren:

 

[CertifiedMike]

Aaaand I backed over it in my driveway while in a hurry to take it to the field.

I was waiting for the punch line that never came.

I'm glad you saved her!

 

[tudordewolf]

I was waiting for the punch line that never came.

I'm glad you saved her!

it was pretty heartbreaking, it happened months ago and I just found it in myself now to post about it.

Edit: its top wing joined the graveyard with the intact tail from my Sonic which took a dive, but also enjoyed a full rebuild with original engine unharmed.