attach motor to gearbox
 

Hello electric flyers,

I'm an experienced RC builder and flyer, but am new to electric flight.

I'm scratch building a Curtis Robin from plans. It will use a Speed 280 motor and a MPJ 4.1:1 gear box.

My question is how should I attach the motor to the gear box? The gear box (black plastic with three mounting lugs) screws onto the firewall. A cup shaped portion of this assembly extends through the firewall into the fuselage. The motor (with pinion gear attached) is installed by inserting into the "cup". It looks like a press fit may be enough to hold it in place, but I am worried that it may come loose. I could glue it in place, but then I lose the ability to take it apart.

I wonder what other builders of electric planes have done to solve this problem? I'm leaning toward gluing it in place, but I'm wondering about other options.

Do you have any experience or suggestions?

(I tried, but failed, to include a picture of my gear box with the motor pressed into the "cup".)

-Joe

RE: attach motor to gearbox
 

Hello again,

I put the picture of the motor/gearbox in my gallery. You can go see it there (if this works). Also here is the url, perhaps that will work also:

http://www.rcuniverse.com/gallery/ga...emberID=365177

Thanks in advance.

-Joe

RE: attach motor to gearbox
 

I looked at a similar gearbox's instructions and this is what was suggested:

3. Once you have finalized the exact position of the motor in the
gearbox, add a small drop of medium CA to both sides of the
motor where it fits into the gearbox. This will assure that the
motor stays in position.

Like you, though, this doesn't sound ideal, but CA tends to have poor sheer strength so twisting it of the gearbox may not be that difficult, especially if a bit of debonder could work it's way in there.

RE: attach motor to gearbox
 

Some brushed motors have 2 holes in the front on each side of the output shaft for mounting.

Does yours?
If so, are there any holes in the gear box that match up?

RE: attach motor to gearbox
 

Time Pilot,

Thanks for the suggestion. Sounds like good advice.

-Joe

RE: attach motor to gearbox
 

Sir Raleigh,

I couldn't find any holes in the gearbox to match the holes in the front end of the motor. And making new holes doesn't look possible due to the design. Thanks, anyway. It was a good idea.

-Joe