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gyrotron
08-01-2012, 02:47 PM
Hello,

I am new to the hobby and wanted to know if the is a special tool/trick to hold the drive dog steady when tightening the propeller nut. Pictures would be a plus!

Thank you

Steven Vaccaro
08-01-2012, 03:13 PM
I make sure the battery to the motor is disconnected and use a small towel/rag to hold the prop thats engaged to the drive dog.

gyrotron
08-01-2012, 03:50 PM
I managed to keep the propeller steady holding it with a piece of towel like you suggested, but then the prop shaft was still free to rotate so I picked a small piece of old leather I had around and used it as a cushion between the pliers tips and the piece of tube the shaft has where the drive dog screws. I finally was able to hold it steady and tight the nut as required. Thanks Steve.

Rocstar
08-01-2012, 04:03 PM
I managed to keep the propeller steady holding it with a piece of towel like you suggested, but then the prop shaft was still free to rotate so I picked a small piece of old leather I had around and used it as a cushion between the pliers tips and the piece of tube the shaft has where the drive dog screws. I finally was able to hold it steady and tight the nut as required. Thanks Steve.

If the prop is engaged in the drive dog and your set screw is tight, you should be able to hold it with a towel as suggested and tighten the lock nut fairly easily. If the nut is really hard to tighten you may have a problem with your thread...

gyrotron
08-01-2012, 04:13 PM
Roc,

I checked the thread with a magnifier glass and it is ok. What happened was that the drive dog of my Mini Wilcat does not have a set screw and it was loose so everytime I tried tightening the lock nut, the drive dog would desengage and rotate in the opposide direction.

Rocstar
08-01-2012, 04:24 PM
Oh I see.. I'm not familiar with that one, no set screw? What locks it in place?

gyrotron
08-01-2012, 06:22 PM
Oh I see.. I'm not familiar with that one, no set screw? What locks it in place?

I guess just friction against the end of the shaft thread.

sanyijr
08-01-2012, 06:33 PM
http://www.aquacraftmodels.com/parts/aqub7852.html

If this is your dog drive and it is threaded? Is the drive still threaded?

I would think you could tighten the prop nut onto the prop and it would lock the dog drive in place. But I cannot tell from your pics.

Try Loctite?

gyrotron
08-01-2012, 06:40 PM
Yes the drive dog is threaded. The prop nut is locked in place and the drive dog is locked too now, no need for loctite. Thx.

sanyijr
08-01-2012, 06:50 PM
So you thread it up the shaft till the dog locks into the non-threaded portion?

A side note, your pic has the right drive a bit close to the stuffing tube. As a general rule, keep about the same distance from the stuffing tube and dog drive as the flex cable diameter. If under load the flex compresses, you can rub the front end of teh dog drive into the brass tubing and cause a mess of problems...

gyrotron
08-01-2012, 07:31 PM
So you thread it up the shaft till the dog locks into the non-threaded portion?

A side note, your pic has the right drive a bit close to the stuffing tube. As a general rule, keep about the same distance from the stuffing tube and dog drive as the flex cable diameter. If under load the flex compresses, you can rub the front end of teh dog drive into the brass tubing and cause a mess of problems...

Yes, you thread up the dog till it locks into the non-threaded portion. Good catch! I'll fix it. Thanks for the tip.