Hi Lemony,

I have been mulling this around in my head all day. Hmm.   

Most small 4-hole motors have a 9mm diameter mounting,
but your motors have a 7mm diameter mounting. That is only 
2mm difference in the diameter which is only 1mm difference in
the radius; the difference from the center hole That means that 
the edge of a 9mm pattern is right at the center of where a 7mm 
format hole would be. So, drilling it out would be challenging at best. 
On the other hand, it could be cut using a drill and use the side of the 
bit in a sawing fashion to cut down the 1mm distance.

Back in the day, that is how we would make an oblong hole out of 
round one; mostly in circumstances like you have here. Since you 
would only have to cut down 1mm per hole, that might just be the 
thing; that is precisely what I would do.    

Later, My Friend, iFly    

Thanks, iFly! I’ll give that a shot. I need to see if there is a frame on my shelf where the center hole for the c-clip isn’t too big.

iFly for the WIN! Awesome solution, good head scratchin...

Harbor Freight has a cheap diamond needle file set that works well on carbon fiber.

https://www.harborfreight.com/needle-fil...69876.html

Hi everyone,

I actually have a set of those files, but will say right up front that
a power drill and bit will get the job done a lot faster and actually
with a bit more precision (sort of) since one would use a 2mm bit.
Hand files just don't have the precision that a drill bit does 
(at least not in MY hands, 

Hey, you have at least 8 holes (2 per motor) so you could try it
both ways and see which one works better for you.

Later, My Friends, iFly  

(15-Sep-2023, 12:16 AM)skywanderer Wrote: iFly for the WIN! Awesome solution, good head scratchin...

Hi Skywanderer,

Thanks. 

I have fabricated so much stuff over the years, that I can generally
think of something if given enough time. Yeah, more now than when
I was younger. 

Later, My Friend, iFly