Tail rotor shaft gear removal

[jperkosk]

Hello everyone! I'm finally getting around to rebuilding my Belt CP v2 CE that I crashed badly last Christmas and I got to a point where I need to replace a bent tail rotor shaft. The problem is it's got a plastic timing belt pulley on it (which is perfectly fine). Can this pulley be removed / reinstalled without getting damaged? It's plastic, so I can't heat it up like I did on the motor pinion...
I got my hands on the crashed tail assembly from another Belt, and it's got a perfectly straight shaft, but the pulley is shot, so I can't just use the complete shaft/pulley assembly.

[ifitaintbrokeitwillbe]

Originally Posted by jperkosk

Hello everyone! I'm finally getting around to rebuilding my Belt CP v2 CE that I crashed badly last Christmas and I got to a point where I need to replace a bent tail rotor shaft. The problem is it's got a plastic timing belt pulley on it (which is perfectly fine). Can this pulley be removed / reinstalled without getting damaged? It's plastic, so I can't heat it up like I did on the motor pinion...
I got my hands on the crashed tail assembly from another Belt, and it's got a perfectly straight shaft, but the pulley is shot, so I can't just use the complete shaft/pulley assembly.

Won't work, get a new tail shaft on ebay. Actually, better yet, dump the CP and get a Trex clone, you will learn to fly sooner, and you will save money.

[jperkosk]

Thanks, I was kind of afraid of that...

[jperkosk]

Originally Posted by ifitaintbrokeitwillbe

Actually, better yet, dump the CP and get a Trex clone, you will learn to fly sooner, and you will save money.

Can't do THAT, that would be a plain betrayal

[mnwizard]

Originally Posted by jperkosk

Hello everyone! I'm finally getting around to rebuilding my Belt CP v2 CE that I crashed badly last Christmas and I got to a point where I need to replace a bent tail rotor shaft. The problem is it's got a plastic timing belt pulley on it (which is perfectly fine). Can this pulley be removed / reinstalled without getting damaged? It's plastic, so I can't heat it up like I did on the motor pinion...
I got my hands on the crashed tail assembly from another Belt, and it's got a perfectly straight shaft, but the pulley is shot, so I can't just use the complete shaft/pulley assembly.

Hi Jerry.

Actually this is a relatively easy fix, I've done it a number of times.

You do have to have a gear puller though.

Put the shaft in the freezer for a couple of hours.

When it's good and cold the metal shaft and the gear will contract.

Wrap tape around the shaft on both sides of the pulley to insulate the shaft, then warm the pulley with a heat gun or hair dryer. Just for a couple of seconds, you want to warm the pulley up a little, but not the metal shaft.

Then remove the tape from the short end of the shaft and use a gear puller to remove the pulley from the shaft. It's just a press fit and the pulley will come off the shaft pretty easy.

To install the pulley on the new shaft, cool the shaft in the freezer and insert it in a vise. Press the pulley on the end of the shaft and use a piece of copper or aluminum tubing to tap the pulley into place.

I'm not in my shop right now, but when I get a chance tomorrow I'll post some pics.

[jperkosk]

Thanks, Jack! That changes the picture, I was afraid the gear was locktited into the place or worse... I'll try it this weekend, the work interferes with my helis again . Unfortunately, I don't have a micro gear puller, so it'll be a quick trip to Home Depot (they're 5 min from my home) to see if they got one, or, if they don't, to find a suitable piece of tubing to push it off in a vise.

[mnwizard]

Using the cold/heat method the gear comes off pretty easy, you shouldn't have any problem pushing it on and off with tubing.

Don't forget to get a measurement from the end of the shaft to the gear so you can put the gear back in the proper position.

With the gear off you'll see that the shaft has a couple flat spots that look like they're for a set screw but there isn't a set screw used with the plastic gear.

Let us know how you're doing, and don't be afraid to ask if you have any other questions, there is a huge knowledge base of Belts here.