Wow! My spindle was vibrating horribly. And, indeed, it turned out that the spindle without a fan spins perfectly smoothly. I balanced the fan in a similar way and now voila! The spindle with the fan at full speed is smooth and silky! Thank you for the video!

Thank you for doing this video. My spindle is much smoother and quieter now.

Nice video. Not a lot of people think of balancing the spindle but it does make a big difference. Any rotating part for that matter. Another option is using an RC Prop Balancer. Also very accurate and easy to use and cheap. Thank you for putting this video up.

This is great :D Just one thing, when using a cheapo spirit lever like that. You can take out lot of error by simply turn it 180 degree to check the inaccuracy and then easily compensate for it to get even better result!

Hi, thanks' a lot. Building soon a new CNC but holding on to my 500W spindle. This should help a lot for the surface finish, especially for aluminum.

I pulled the fan then mounted it in a model airplane propeller balancing rig and added drops of CA glue plus activator to the inside of the rim. it comes out perfectly with no guesswork.

Another point... I see this is a different z axis than the one you built in a previous video. The lower bearing block of that motor has 6 screw holes. 2 are used for the long bolts coming from the upper bearing block. The other 4 are empty, unused. In your other z axis, you closed those extra 4 holes by using them in the assembly. But in this axis, they aren't used. Wood chips will very quickly get sucked into those open holes, "clogging" the rotor. Motor will run hotter, misbalance will occur internally. And, excess drag will overload and trip the power supply. I simply installed 4 short screws to close them off. Solved that issue very well.

Cool, I'll definitely try it on mine, thanks for sharing. I've used modified pc fans as tachometers for othet projects in the past, I'm thinking of adding a fan with that capability to my spindle, so there's no need for the external sensor.

Very cool, one of those... Why didn't I think of that videos! Thanks!

Great video on balance. Thanks

Brilliant tutorial 👍

Thank you...New subscriber here...just starting to get into hobby CNC'ing.

It's also a flywheel as well as a fan! The outside surface is further from the pivot, so drilling there needs less material removal. You'd want to start at the vertical centre in the other axis to not add a secondary wobble though too, like a pair of bike cranks spinning fast.

I just tossed the fan in the garbage and threaded an air fitting into the end cap. Using shop air and a small regulator to cool it.

Excelent video.

Keep making videos, subscribed.

Ooh this is a great difference.

OMG, excellent, thanks.

Hi, brilliant Tutorial !! But where can i find the STL of the fan ? Greetings from Germany Jari

Have you shared the stl for the fan anywhere?

i just added a pc fan on the spindle using metal brackets and removed the top one altogether.

You could also use a dremel and a very small drill or burr, its easier to put a little back if needed, just half fill the hole again

Next time do dynamic balancing with accelerometer. I am experimenting with my phones sensor and a mpu6500 sensor chip. I dont think it will be accurate enough for my liking but I dont have 200 dollars for the right tool.

Good night friend. Thanks for the video. How do I ground this 800w spindle?

I would rather remove mass somewhere else and not reducing impellers surface. Or even adding some drops of glue on the opposite side. Or in this case add filament with 3D pen.

Question: Have you already tried running that motor for extended periods without the fan? I've not yet tried, but I am tempted. In my case, the fan really does not seem to be effective, as the motor casing remains quite warm. However, the fan does indeed move a lot of air. I think the real design flaw is a need for heat sink fins on the motor casing. Also, my next upgrade project is to build an integrated case. That will include a high air flow system for removing and evacuating chips. Theoretically, that will also be much more effective for cooling the motor.

merci pour votre idée. la question que je voulais vous poser c'est combien d'heures continus pour se moteur ?

Hi Matt, thanks for this video! This will make a world of difference! I've got the same spindle, just haven't used it yet. How do you like the 800 watt version? Greetings from the Netherlands!

need to balancing the collet nut too

Is the C clip also "balanced" ? Seems like it would have to be since the vibration was greatly nulled after the fan was balanced. Great video, I am try this right after dinner! I was actually searching on a more balanced motor and didn't realize it was the fan all along!

better cooling and balance have stay fan piece off, and use outside motor elektric pc fan, lot easy and better fan, not noise lot and not destroy spindle balance.

I have question I use Comgrow CNC every day. . Unfortunately, recently the bearings in the spindle broke and I had to buy a new spindle. Because it was nice to get an original one, I bought a Genmitsu GS-775M 775 CNC Spindle. Unfortunately, it does not want to work with the Comgrow CNC motherboard. It starts shaking strangely for a second and then stops. Do you know what could be the reason for such behavior?

I have one of these motors but not sure of the need of a fan as the motor is mounted in a solid aluminium mount which I thought would be sufficient as a heatsink unless someone knows better

Hi Matt, what do you think about 800W but with water cooling?

You can always just make a new fan using the cnc if you end up removing too much

Here is an alternate idea that might be even quieter, just replace the existing fan with a better one kzfaq.info/get/bejne/eLthebSpzsiap2w.html

Hello, thank you for your balancing video there is also another problem with this type of spindle, since the bearings are adjusted by a rubber kzfaq.info/get/bejne/aZOkmMqomZ6yc6c.html

lol like indian scammer ....first test 24000 rpm end test 900 rpm !!! gj best bite click of the year!

my patience level having to check the wheel every 5seconds would never allow this....😭 but still brilliant idea though.👍🏻