Electric in heavy Puppeteer

[i12fly]

My Puppeteer is quite heavy at 9lb 2oz and is nicely powered with an SC70FS.

However for winter I'd like to convert it to electric. Whilst 100W/lb is certainly good for monoplanes with basic aerobatics I've never done a biplane with the greater drag. Does the same rule of thumb apply or should I increase the power/lb?

I've got a good collection of 4S batteries, 4000 and 5000 and would like to use them but struggle to find a modest cost motor that will carry the current. I don't want to pay a large price for a motor as it will not be a regular flyer.

Any advice will be appreciated. I guess I'll probably need to go to a six S battery

[David Davis]

Check out what this guy hasa done with his Magnatilla. Both models will fly on similar power.

**LINK**

[MattyB]

100W/lb will be fine on something like this; 80W/lb would be ok for scale type performance. You may want to consider working around an 8S setup with a lower kv motor so you can use your 4S packs in series and to reduce the current required (meaning a cheaper and lighter ESC can be used). HV setups in larger models like this tend to be more efficient than dragging more current out of a lower cell count pack.

Edited By MattyB on 29/07/2017 15:46:08

[Braddock, VC]

If it's not a regular flier why not leave it as it is. Personally I wouldn't play with electrics.

[Andy48]

I have an electric Puppeteer and it flies really well. It runs on a 5S. However it was built as an electric model, and the cowl and motor swing open to get the battery in.

Making space to put a quite a large battery in and change it is going to be your biggest problem in converting. The battery must be as far forward as possible.

[i12fly]

Thanks for the advice chaps, perhaps I'd be better then to use a couple of 3s 2200 in series to keep the voltage up and lower the current, I'd not considered this before - that's the great thing about the forum, people suggest alternative ways and these can be tailored to what you've got. Having got a fair number of 3S 2200 and 4S I don't really want to set up another lipo size. I certainly agree the point about keeping the weight forward, it has got 7oz of lead in the cowl now even with the 70FS in place. I think it is a Mk1 version, I bought it half made so was able to adapt it to want I wanted, quick assembly at the field, just 5 screws.

[MattyB]

Posted by Braddock, VC on 29/07/2017 17:48:58:

If it's not a regular flier why not leave it as it is. Personally I wouldn't play with electrics.

Super helpful response . The OP does want to convert it, so your personal preference is irrelevant; it's his model after all!

[i12fly]

I like IC but... there are a few reasons I now prefer electric. Just 2 out of my 9 planes are now IC.

I don't like fuel all over my hands particularly in cold weather, my skin cracks easily and badly

I don't like cleaning goo -same reason

The field is fairly small/ narrow with trees on the downwind leg and stone walls to miss on landing, whilst I can't remember when I last had a deadstick, I see others and I'd say 2/3 end in tears. If the deadstick is outside our field we are surrounded by a field that is a dump for pig slurry (avoid an east wind), and the others have a new farmer who is not the friendliest and best to be avoided. So, touch wood, up to now I find electric more reliable. Electric doesn't sound as good but then again IC still doesn't sound like the full size IMO.

[Trevor Crook]

Good advice from Matty and Andy above. If you use your 2200s to make up 6s, and prop for about 700W, it should fly ok. This would draw around 30A flat out, so cruise will be at around 20A. Duration will only be around 5 mins of mixed flying, so if you make the battery bay bigger than you need, you can fit bigger packs later if you want to.