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2465 Fan Collet Thingy


Li Gangyi
 

That is ultimately my plan. Gonna cut a screw down as a stud and put the
same resin in the there and cure the whole thing in a UV chamber, should
get rid of any issues with the square edges in the initial hole.

I tested a piece to destruction, it broke at the collet slits when I side
loaded it too much on the lathe, which is a fair bit and not anything id
expect in use. This is with a exterior collet I made to fit this collet, I
have yet to test the strength of the threads, i will do so next. Torque it
down hard with some washers in between and see how much it takes to strip
it out.

On Sat, Aug 15, 2020, 5:54 AM <scm@...> wrote:

A bit of background. I am not a 3D printer guy. If I were making this
part, I would machine
it with a lathe and a milling machine. Also, I might make it entirely out
of metal, depending upon the ultimate application. That having been said -
If I were making t out of plastic, I would consider tapping a 6-32 hole at
the stud end and epoxying in a metal stud ( sawed off piece
of a machine screw). This should end up much stronger than an all plastic
part. The epoxy would ensure strength and reliability and guard against
unscrewing.




Li Gangyi
 

Alrighty, I've successfully made a couple of these and tested them out (although I don't own the actual fan/scope).

https://groups.io/g/TekScopes/album?id=252111

Threaded and stud added (m4x0.7), I'm not sure of the stock hardware (was it a nylok nut and spring washer for example?). I tested a few to destruction with a 1.8mm shaft (actually an air adapter for filling up basketballs and such) and cranking it down until I heard a crack, all the failures where at the collet, non stripped out. They failed with way more torque that you'd normally put thru such a small nut, although reefing on it would crack it. I have no real means to measure the amount of torque required (the smallest torque wrench I have goes down to only 30inlbs).

If anyone would like a few to try (I'll ship them with a set of hardware), or you want to tap them for your thread size, i can leave the hole unmolested. contact me offline and we'll sort that out.