G/P Old timer 40 Conversion

[billrcpilot]

I have this Great Planes old timer 40 still in the box, 72 ws and disigned to fly on a 40 to 52 glow eng. three (3) channel, i am new to the electric world and would like to convert this to elec. any suggestions on what type of motor, battery, esc. etc. would be best for this convertion. i've been flying R/C for over 40 years, but all glow. Thanks for any help you'll can give, :rolleyes:


Bill
Retired USAF

[Dereck]

Bill
With an unusual type like this, you might get more ideas searching for whose done what to similar models - any of the Sig Kadet series or mid-sized Telemasters should give you plenty to read.

Hobby Lobby and NorthEast Sailplanes are two vendors who have a lot of practical experience matching motors to sizes of models. I can't give you any modern recommendations - unfortunately, I only buy decent stuff, so it doesn't wear out quick and force me to buy more, newer stuff ;) So most of my motors are ancient (more than six months old mostly :) ).

Rcommendation has always served me better than paying for prediction programs, FWIW. I built my first electric in 1985 and haven't flown a glow model in the last five or six years now.

The only snag with GP kits is weight - I don't think anyone there can spell the word, though their aerodynamics are usually pretty decent. As a lighter model is still the cheapest upgrade going, you sound like someone who can take care of those issues.

Hope that helps, good luck

Dereck

[billrcpilot]

GPBill
With an unusual type like this, you might get more ideas searching for whose done what to similar models - any of the Sig Kadet series or mid-sized Telemasters should give you plenty to read.

Hobby Lobby and NorthEast Sailplanes are two vendors who have a lot of practical experience matching motors to sizes of models. I can't give you any modern recommendations - unfortunately, I only buy decent stuff, so it doesn't wear out quick and force me to buy more, newer stuff ;) So most of my motors are ancient (more than six months old mostly :) ).

Rcommendation has always served me better than paying for prediction programs, FWIW. I built my first electric in 1985 and haven't flown a glow model in the last five or six years now.

The only snag with GP kits is weight - I don't think anyone there can spell the word, though their aerodynamics are usually pretty decent. As a lighter model is still the cheapest upgrade going, you sound like someone who can take care of those issues.

Hope that helps, good luck

DereckThanks Dereck:

It never fails that i get great information on this web site. its people like you who make this a wonderful hobby.

Bill

[Dereck]

Hi Bill
Two ways to do this - go modern, outrunner or geared BL, LiPo battery - go read all the horror stories on the battery tab first - latest LiPo charger (go talk to FMA Direct about LiPos and chargers, tell Fred Marks I sent you, he's almost a neighbour of mine. Fred was flying LiPo in the US before anyone could spell it!)

OR

Find a used and loved Astro 05 or 15, with what Astro called their "Superbox" Back it up with good old fashioned NiMh cells - there was nothing wrong with flying with around 2000mA a couple of years ago and that capacity comes in smaller cells now, or you can pick up reasonably priced 3000+ mA cells. Battlepacks or Cheap Battery Packs have good reps. If you don't like soldering, Pete at MEC is the go-to guy with his "Powertubes". Chargers are pretty cheap for NiMh and they are far less tricky boogers to live with than LiPo.

Your model should have the room and carrying capacity for the older stuff, easily. It's not fashionable, but there's a huge knowledge base around on NiMh cells that makes them a lot easier to diddle with, and you have enough to cope with going from wet to electric power at times.

I have only vague recollection of your kit, but it should convert up and fly around like the Kadets various, and maybe convert you to a form of flying that doesn't require you to haul model cleaning stuff around. My Sue reckoned my going all-electric was great - something about how the smell of my 'flying clothes' permeated the entire house whenever I returned from a flying session.

Regards

Dereck
Retired Royal Air Force

[cooper998]

Bill,
I have a couple of "40" size planes converted and have found the AXI 2826/12 motor to suit my needs best. I currently have a GP Trainer 40 with that motor and a 35amp Castle speed control running off either 12 nimh 3300 cells or 4s 4000mah lipo. Either battery spins a 12x8 APCe prop. All up weight is 6 1/2 lbs with the round cells and it has no problem flying that weight around. Running times run from about 7 minutes of spirited flying to over 15 with the lipo and easy flying.

Most of the similar outrunners from other manufacturers should provide similar results, just remember an inexpensive motor is not always a "good deal".

cooper998