What I like and what I don't like about the MicroMill

Hi MicroMill users,

After using the MicroMill for some weeks and after finishing some projects I came across some problems but also appreciate some of the features.
First of all I have to say that the MicroMill support is awesome!

Pro:
It's incredibly small and easy to use!
When you have to work somewhere else - different room or different workshop - just take it with you.
It's easy to modify something.
It's fun,

Contra:
The proxxon 240 is not made for cnc milling neither is the flexible shaft made for it. After my first proxxon stopped working I luckily got it repaired for free thanks to Josh's great support, but now I stop it every 15 minutes to let it cool down. That works, but nothing is finished in 15 minutes, right?
Additionally, the flexible shaft is now starting to break. It makes some really unhealthy sounds.
My plan is to directly mount the proxxon without the flexible shaft. And on the long term, maybe get a Kress.
I also had some problems with fixing the material onto the stage. The sticky tape delivered with the machine is not very strong. I had several broken 1mm tips because the material popped off. Now I use strong metal brackets in addition.

I am not sure if I would buy it again to be honest. As a first step to learn cnc and to check if I need to upgrade someday its too expensive and unfortunately too limited die to the proxxon...

Cheers
Nils

Hi Nils,

Thank you for the honest review!

Sorry to hear the flexible shaft is starting to go. In our testing we were running the 240/e for severla hours between stopping it - what speed are you running it at? If you’re running it excessively fast for the material, or attempting to cut too much at once the increased resistance will cause everything to work harder.

The flexible shaft was chosen because it was definitely the ‘best in test’, but Proxxon themselves admit that it is happiest in a straight line. Perhaps if you’re starting to have issues with it - elevate the 240 above the machine to keep the shaft a little straighter (but not taught). This should get rid of a great deal of noise too!

While we do have a couple of MicroMills left, we’re taking a bit of a pause from production to reassess a few design options now we’ve had the machines out there for a few months and have gotten a wide range of feedback.

Thanks again Nils, remember Josh is always available via email if needed!

Hi,

Usually I work with wood or mdf/hdf. I am running at 16k - 20k RPM and I dive max 0.5 mm and go max 200 mm/min (slower and smaller dive in for 1mm bit). Is that too much?
Can you recommend me better suited parameters for the MicroMill? I looked up some blogs and websites to get a feeling for how fast I could go...

Hi Nils.

Id say the spindle speed is probably a little high - you dont want it to get too hot as it’ll blunt the tools and potentially damage the part too.

The MicroMill is very similar in ability to TheOtherMill - after all, we only made the first one for ourselves because machines from Roland and OtherMachine (now Bantam) were too expensive.

For that reason I’d advice you to start your material setting investigations on their superb website - https://support.bantamtools.com/hc/e...2374-Materials

These will be conservative settings, but definitely a good place to start!