HELP! I'm setting up for the "prop adapter" version for the Grasshopper. I have to move the shaft to the other side of the motor. It seems all there is to it is a 'clip' which grasps the shaft. How do I remove it? Is that all I need to do?

I'm stuck on this step and it's driving me crazy! I want to fly it before we're banned by the FAA

Thank you

From the Park 250 Manual:

Reversing Shaft Installation
This outrunner motor has a shaft, which currently exits through the fixed part of the motor. If you want to reverse the shaft to exit through the front rotating part of the motor, follow these instructions carefully for changing the shaft installation. NOTE: The user assumes all liability for damage that may occur.
1. Loosen the two screws on the front of the motor.
2. Remove the small black e-clip that rests against the bearing.
3. Slide the shaft through the motor. It may be necessary to use a small hammer to lightly tap the shaft. It is very important that you do not bend the shaft in this process so use extreme caution to assure this does not happen.
4. Re-install the e-clip on the end of the shaft against the bearing by sliding it into the groove in the shaft.
5. Retighten the two screws on the front of the motor.

Follow the directions above carefully. Many have damaged their motors in the process... not fun stuff!

I also recommend you use a drill press to press out the shaft. You can use a drill bit slightly smaller than the shaft and installed upside down in the chuck as a 'drift pin'. The shaft can be quite tight so be patient.

I would also check out the L-4 Grasshopper thread:

http://www.rcgroups.com/forums/showthread.php?t=1112900

And some of the Park 250 shaft reversal threads:

http://www.rcgroups.com/forums/showthread.php?t=1222246

Scorpion has a nice shaft replacement video.

How to Change a Shaft in a Scorpion Motor by Innov8tive Designs (11 min 30 sec)

The process is similar for many motors. It'll give you a good idea of the correct way to perform shaft replacement which is similar to what you would do on a reversal.

Thank you very much... how do I remove that small black e-clip? I really don't want the prop saver version but should I do it and avoid the trouble?

You can remove the clip with the aid of a very small screwdriver.

Here is a hint for you, perform the clip removal inside a large clear plastic bag. The clip WILL go flying when it's removed, the bag will hopefully capture it.

Kevinfred, use a small straight blade screwdriver, slip it between the shaft and the clip at one of the spaces around the clip. Twist gently and the clip should move out of the groove it is in. BE CAREFULL not to launch the clip across the room or the carpet monster will get it. You may try removing it while holding the motor in a gallon sized plastic bag.

AND I tried the same thing for my eflite L-4 Piper Cub. I am an Aero Engineer with an A&P mechanics liscence. NOTHING I could do or knew how do do could get that shaft to move as stated in the instrucitons above, this included tapping with a hammer, heating the shaft, heating the motor and chilling the shaft and putting it in a press. I eventually gave up and just fly with the prop saver.

I changed mine to a prop adaptor as well... not to hard with an arbor press... just make sure you keep everything square when you press. I like having a prop adaptor...it does look better. HOWEVER, the 2mm shafts bend if you look at them cross eyed even a gentle nose over on GRASS has bent my shaft and this is when using flexable GWS 7x3.5 or 8x4 DD props.

If you get it converted go and buy a few shafts... you WILL need them sometimes it's hard to see the bend... I can usually hear it as prop noise/vibration before I can see the bend in the shaft.

Here is my L-4 Grasshopper. The motor is an Infinite A1705-1800 that normally ships with a wobbly prop adapter. I pressed the shaft out and swapped with a longer shaft and E-Flite 2mm prop adapter. It works very well!

P.S. I wanted a civilian paint scheme so I removed the decals. My apologies if offended anyone.

Originally Posted by Majortomski

NOTHING I could do or knew how do do could get that shaft to move as stated in the instrucitons above, this included tapping with a hammer, heating the shaft, heating the motor and chilling the shaft and putting it in a press. I eventually gave up and just fly with the prop saver.

That's what I've heard as well. Seems the shaft is firmly glued/pressed in place on some of these motors.

It is normal for the shaft to be a sliding fit in the inner races of the bearings and a press fit into the magnet housing. The best way to get a pressed in shaft out is to:

1 - remove the grub screws

2 - Find a deep socket wrench or piece of tubing that will go up into the magnet housing so that it will support the housing as close to the shaft as possible. It should be just a little larger than the shaft and long enough that the shaft can be pressed down into it.

3 - Press the shaft down into the tubing until it falls through. If the shaft is flush with the end of the magnet housing at the start or when it is pressed down flush with the end, put a short cap screw that is smaller than the shaft against the end of the shaft and continue pressing.

I usually do the pressing horizontally in a bench vise or vertically on a drill press.

If you can find non-ferrous tubing it is easier to use as you don't have the magnets wanting to stick to it.

Jack

Be careful-there appear to be an older park 250 and newer one -if you try to move shaft in older one the cage collapses and motor is killed..the metal is quite brittle. Me and buddy killed ours- he sent his to horizon and they replaced it no charge as it was new. I have found the Rimfire 250 to be superior in power and friendliness in that model

If I were to do it again, I would just get Ken at Subsonic Planes to set me up with a DM2203-1600 with an extended shaft and prop adapter.

Wait a minute... I just ordered this very same motor for a couple of other planes! Maybe I should just swap one in...

Oh wow , great idea removing the c-clip in a bag , i must have 100's of them in the carpet of my model room ....

Originally Posted by speed2004

Be careful-there appear to be an older park 250 and newer one -if you try to move shaft in older one the cage collapses and motor is killed..the metal is quite brittle. Me and buddy killed ours- he sent his to horizon and they replaced it no charge as it was new. I have found the Rimfire 250 to be superior in power and friendliness in that model

I haven't done it with on a Park 250 but supporting the magnet housing on a tubular object that is just slightly larger than the shaft, as I describe above, and then pressing the shaft down into the tube should keep you from collapsing or distorting the cage or end bell.

Doing it that way is specifically intended to localize the pressing forces as close to the shaft as possible and also to avoid putting any pressure on the ends of the magnets where they might be exposed at the open end of the magnet housing.

If you have a bent shaft, cut it off close to the end of the magnet housing to get rid of the bent part before you try to press the shaft out. The odds on getting the bend to go through the housing without damaging the housing beyond further use are very small.

Then make a new shaft, that is not that hard to do and you either buy a shaft or even get one from a scrap CD or dVD drive. More details here:

http://www.rcgroups.com/forums/showthread.php?t=1240725

Jack