barelias

I am also upgrading to kyosho magnetic mayhem:

1-Would the pt take off from grass with the kyosho motor with 6 cell?any one tried that or should i make it 7cell.

2-Can the kyosho magnetic run 8 cell,3000nimh??? or that would fry the motor?

3-Do i need a battery for the reciever considering that i got a 6cell 3000nimh and a speed controller with motor power cut off to save power for the controls.is it safe without the reciever's battery?

4-Wheels, the manual recommends 2.5" wheels, would 3" or 3.5" help the pt to take off from grass

5-Where could I locate the thread that shows how to add aerlions to the pt.

Foamaholic

My Feedback: (1)

Big wheels help grass takeoffs. I use 3" light foam wheels on my PT.
The best thing you can do it use a gearbox. Greatly increases thrust, lowers amp draw, extends run time.

barelias

foamaholic, r u using the thurstmaster motor or the magnetic mayhem one? and what gearbox r u using?

Foamaholic

My Feedback: (1)

I've used a lot of motors on it since I built it in 1991.
After going through a bunch of Goldfire motors I got an AstroFlight 05 cobalt geared motor.
Still ran it on 7 sub C's.
A couple years ago I got a Jeti 16/15/4 brushless motor and ran it direct drive on 8 nimh's.
This year I switched to Thunder Power 3s 2100 lipos. This saves me 5 oz. over the nimh's.
The plane just keeps getting better.

Matt Kirsch

My Feedback: (21)

The Magnetic Mayhem will take 8 cells if you gear it. I believe the ratio is 3:1 and the prop size is a 12x6, but you might want to look that up with the search feature.

barelias

another question,wheels can all be 3"?even the front wheel? the manual recommeds 2.0"front wheel and 2.5" on the back.for talking off from grass im thinking to make them all 3".should i?
also my servos seem to be a bit tight in there .they r jrNES 507.are they the right size?
to make them move comfortable ,and void having the gold-n-rods toughing the side of the fuselage ill have to move the clevise on hole.(u know the servo arm or wheel has holes) would moving one hole inside give less rudder movment to less effect?

Foamaholic

My Feedback: (1)

You want the wing to sit level or only slightly raised, so use a front wheel that will allow this.
On mine I use 3" all around. Make sure they are light foam ones, not the heavy rubber ones.
It's the nose wheel that tends to dig in so use 3" if you can.
If the wing is slanting down it's hard to get lift under it to take off. You end up having to jerk the elevator up to get it to take off. If the wing is slanting up it tends to leave the ground before there is enough speed to fly, resulting in a stall on takeoff.
Why can't the gold-n-rods touch the sides?
Moving to a closer hole on the servos will result in less control throw. Maybe you can move to a closer hole on the rudder and elevator horns to compensate.
Don't know your servos, but full size servos can be used, they just weigh a little more.

barelias

About wheel colars: should i put one colar per wheel or at the front wheel i should put two colars one on each side?

the pt antenna looks a bit messy , is it ok to put it inside the plane just an inch goes out of the plane??should i put the antenna inside a plastic tube ,similar the one i used for the servos?

Foamaholic

My Feedback: (1)

Put 2 on all the wheels if you can, especially the front one to keep it from rubbing the axle.
Route the antenna away from electronics and metal pushrods. For this reason you might want to put it in a tube so it doesn't touch any electrical components.
You could also run the antenna out between the wing trailing edge and the fuse, then attach it to the vertical stab. Put a pin in the top of the stab then tie a rubber band around the antenna.
Don't curl it up or cut it off.

barelias

about the gear box that is good to take the thurstmaster or the kyosho magentic mayhem motor. i was told it should be GD600 3.0:1
but the one i could find at the local hobby shop was 2.5:1, should i buy that one and change the pinion to 3.0:1? or how does it work?
would 2.5:1 be enough for the magnetic mayhem motor if im using 8 cells?

also,that set up takes a 12x8 properller,should it be the folding properller so that it will not touch the floor or should i extend the landing gear for a non folding 12x8prop. i dont wana have to raise the landing gear .thanks in advance

Matt Kirsch

My Feedback: (21)

The stock pinion included with the GD600 is something like 2.5:1. Great Planes sells several optional pinions for this gearbox so you can get as little as 1.7:1 and as much as 3.8:1, IIRC. Optional pinions from third-party vendors will net you as much as 4.6:1. The gears are a standard "45 pitch" so any pinion with that pitch will work.

If you want to use the 2.5:1, you will need a different, smaller prop or you will overload the motor and burn it up on the first flight. What size prop that is, I don't know, but I do know that the 12x8 and 3.0:1 is an optimum combination for this plane.

You may as well leave the landing gear completely off the plane if you're not going to extend it so the prop will clear the ground. Then a folding prop will be a good choice. Otherwise, just get yourself a piece of piano wire a.k.a. music wire the same diameter as what came on the plane, and bend up some longer legs. It's not difficult, and is nothing to fear. Total cost of materials is a couple bucks.

barelias

i have installed the magnetic mayhem with GD600 ,3.0:1 gearbox. havent flown yet but just running the motor i can tell its powerful.but i ended up installing 10x8 properller,just for now until i have time to raise the landing gear and make it steerable.dont like hand launching.the 10x8 clears only about 1" which means it will be lawn mowing the field grass. longer steerable gear is not that hard is it?

also, the battery hatch, after covering is done should i cut the covering so that the holes of the hatch are showing?for cooling air to come in? or the cooling openings that r under the gear r enough??