Scale Soaring UK

Having lost our club tug, I decided it would be better to try and electrify my Roedell Ventus 2c, enabling me to fly it from our local flying site. Reading Elliot's experiences with his Ash, I went down the same route and used a Hacker A50 14L with the glider extension and a Jeti Mezon 120A ESC. I fitted the motor in the same way as Elliot and initially checked out the static power using a 6S pack. I tried an Aeronaut 16" X 10" carbon prop and this generated 1400W and pulled about 70A which was close to the predicted figures from the Hacker web site. The 6s pack was made up with a pair of Overlander 2900mah 3S batteries, as these could be fitted under the binnacle in the cockpit. I also tries a GM 16" x 10" narrow blade carbon prop and that generated figures of 1200W and 54A, showing the difference a simple prop change could make. The model weighs about 6.5Kg and is 4.8m span.

I built a launch trolley from ply and fitted 6" diameter wheels to help with rough ground or long grass.

The first flight was an anti climax as the model took off very quickly, even though the grass was quite long. Unfortunately I've been unable to upload the video of the first take off, but it left the trolley after about 30m and climbed out at about 40 degrees. As there was no lift about, I powered up again and those two climbs only took about 12% of the battery capacity.

I'm looking forward to next season, when I can fly this model when the weather is better and overall I'm very pleased with the results.

Hi Roger
I would like to try this with my Alpina 5001E is your trolley your own design ?
All the best
Jess

Hi Jess,

It's loosely based on this design:-

https://www.topmodelcz.cz/index.php?&de ... l&id=17578

Regards

Jess,
I think you are looking for something like this.
I think it was put on the forum sometime ago by John Greenwood, but I may be wrong

Ah ha thanks guys time for some innovation

Jess,
Did you note the pdf attachment as well?
This gave a drawing of the ply side pieces (scale if necessary to suit your model size)
Space the sides using threaded rod from your local DIY store, add some wheels and Voila!
Peter

Roger, just wanted to say, great! that's one hell of a motor for your model, plenty of scope for future upscaling!

I am just pondering my next project to electrify, after I've converted my Vagenecht Pilatus to a stabilised receiver to take the stress out of self launching...

Ell.

Elliot,

If I could work out how to post a video from my phone, you could see that the model is "sprightly" from take off. I'll see how things go over next season and if all goes well, I might go for something slightly larger.

Regards

Roger, I'd be interested to know your technique for getting the nose to spinner as good as you did.

Hi Elliot,

I measured the diameter of the spinner base and added 1mm on radius for the cut on the fuselage nose. The gap between the spinner and the fuselage was spaced out with 1mm ply, while the Hysol on the engine mount dried overnight. The rest was luck

Regards

H Roger, Elliot was as he admits lucky that the spinner fitted the nose of the glider so well.

Often the taper of the nose is completely different to any spinner on the market,or the taper on top of the nose is different to the taper on the bottom. Or its just not symmetrical at all. The Tangent Alpina for an instance has quite a pointed top to the nose which makes for a very oval hole when you first cut it off. The way to help this fit a round spinner is to heat the nose area at the point of connection in very hot water(not boiling but too hot to bear ones hands into it)
Keep dipping the model into the water slowly and carefully, allowing the in-water time to slowly increase until the nose material becomes pliable but not soft.
Then with a selected glass bottle such as a small coke bottle ease it into the inside of the nose so that it takes on the roundness of the bottle. Be careful not to over distort but to just alter the shape from oval to round.
If one is super clever they can have the motor mount close and before the material is completely cooled the motor mount can be fitted into position which will also help the nose to hold its new shape until cooled.
Always allow to cut back to the desired diameter of the spinner rather then working without any leeway for final fitting.

Finally do not use a heat gun as it is too hot with too wide a heat source for this exercise. Ter.

Thanks fellas, Roger, you obviously have a gift

Terry, thanks for that, next model will probably get a torcman prop driver - so no nose cutting! however the warm water technique will see the light of day here in west Wales...

Cheers, Ell.

I guess I was lucky, in that the Roedell Ventus nose was close to circular at the spinner junction and Terry's advice could come in handy if I try on another model.

The Ash was far from round, I had to convince it using the former and a draw bolt arrangement whilst the epoxy set. Next time I'll get the kettle out.