I had NOT originally noticed the pin in the middle of the tool that 
holds the motor down. Thanks for the video showing that feature.

Consequently, I did not include a pin to hold the motor down.

Even though the original DIY tool should work fine, I will work on 
a design that has some sort of pin in the middle. Hmm. 

Thanks.

Hey IFly, do a Google search for "pinion puller" it might give you some ideas.

Hi Timmy,

Thanks for the suggestion. Yeah, that is the concept. 

The Gemfan Prop Locket works in that manner as well. I did not realize that it is
sold by PyroDrone for $ 8.90 USD or I might have added one to my last order which 
was today, by the way. I am putting it on my Wishlist...maybe on my next order.

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The DIY design can be modified for the holes; the trick is the threaded piece for
a bolt to turn through. On the one hand, the top plate could be made from a 1/8 or
so piece of material, drilled and tapped; then the bolt could have the tip ground
down to 1.0 mm. On the down side, things get a bit more challenging unless you
have the tools and skillset. Something a bit simpler, but a little harder to use would
be just a nut on the bottom side of the top plate. If the nut was secured to the bottom
of the top plate, then that would solve that issue. Also, it might be easy enough to just 
hold the nut with one's fingers while turning the bolt with the other hand. 

I was really looking to design something that was cheap and that most anyone 
could build. Ahhh...anyway.

I might still toss in a couple of revisions for those willing to undertake the project.

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As mentioned a few posts back, my modified el cheapo prop removal tool worked
really well. I just took one of those cheap tools that often come with props and 
used a bench grinder to thin down the leading edges of the tool where it goes
between the prop and the motor housing. I guess if you don't have some method
to grind down the edges, then that might be challenging as well. 

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Hi fpvapnea,

That Gemfan Prop Locket was a good find. Thanks for sharing. 
Yeah, adding the video helped as it showed the part that I had
originally missed. Thank You. 

Thinking that it was just the 2 bolts and missing that it was also
actually a pinion puller, I thought that a simple DIY project would get
the job done. In fact, it still might be better than just using one's
fingers. 

Thanks, iFly.