davidej

Hi

I bought a slightly damaged Discus kit at an airshow on the promise from a friend that someone at his club had converted to a really nice electric soarer.

Being a confirmed IC man, I am new to this leccy lark. I want to go brushless and Lipo.

The plane is

105 in span

likely weight 3.5-3.75 lbs

Someone suggested I needed 500 watts which would mean 50 amps on a 3s 3700mah 20c battery. This sounded a bit overkill as I only want a fast climb to height - not a hotliner.

Any thoughts please

Thanks

David

Flyfalcons

David, 400-500 watts is probably what you're looking for with that size airframe. My 157" 10-pound Discus uses 1200 watts and climbs well at about a 45 degree angle. What size spinner does your sailplane have? A larger spinner diameter will allow you to install an outrunner motor, otherwise if it's a smaller spinner like 38mm then you'll want to install an inrunner motor with gearbox. I have flown a sailplane with the Multiplex 400 brushless inrunner with gearbox propped for about 450 watts and it was a very smooth-running setup without being too expensive.

davidej

I havent got that far yet - I am still examining the contents of the box and wondering what to buy!

The nose cone angle is quite wide. I hope to use an outrunner and was thinking of cutting where it is about 40mm diameter. I would then install a firewall the length of the motor further aft. As the fuse widens rapidly I should be able to fit a, say, 50mm max diameter motor.

Flyfalcons

David, I misread what you posted earlier. I thought that the actual glider you purchased has already been converted to electric. In that case I would recommend something like an Axi 2820 motor with 40-amp ESC. When I built my 4M sailplane I sized the firewall for a 45mm spinner and glued in a 1/4" ply firewall to the nose. I then installed an Axi 4120 motor directly to the firewall and had ample room for the wires to clear the motor as they went backwards. If you size your firewall for a 45mm spinner then you should have absolutely no troubles fitting a 2820 or similar diameter outrunner directly to the nose.

vasek

My Feedback: (4)

Hi David,

if you can correct the "Discuc" to Discus in the title of this thread you might get more inputs >for the search engine key word to "kick in"

davidej

Vasek

You are quite right - I hadn't noticed.

How do I do that or is it easier to start another (correct) one.

David

vasek

My Feedback: (4)

there should be an EDIT button in the upper right hand side of each of your posts

try your first post and you might be able to edit the title, not sure tho

maybe someone else can chip in...