Centroid Community CNC Support Forum

Hello,

Sorry for the dumb question but i am very new. I bought an Optimil M4HS retrofit with Centroid Acorn. this one is an enclosed CNC machine with originaly a flood coolant. THis machine have been transformed to monophase currnt so the flood pump doesn't work anymore. NOw i am wondering what the best approach i i like to cut steel and stainless steel for personal use,so i need some cooling. I know mist coolant (could be easier to install ) exist but i am a bit affraid i can be toxic in this enclosed space ( it's a garage and I am not likely to open it and we have cold winter.

Add a small vfd for the coolant pump motor. For fractional Hp motors, they are usually less than $100. You'll also want a small aquarium bubbler that runs continuously to help keep the coolant from turning rancid.

Yes VFD for the pump, but I would use thin pure oil with a full enclosure rather than water based stuff...


Uwe

The seal materials in a lot of newer machines will not stand up to straight oils. Straight oils are better for rust protection for machines that are infrequently used, but they still are prone to bacterial growth.

tblough wrote: ↑Sun Mar 23, 2025 10:44 am The seal materials in a lot of newer machines will not stand up to straight oils. Straight oils are better for rust protection for machines that are infrequently used, but they still are prone to bacterial growth.

We are running all CNC and grinding machines on straight oil in my job, that is lots of better for machine live than water based cooling, but not as good with cooling.

For my hobby I am also using non water based stuff for MQL.

Uwe

For low power, fixed speed motors, you can often power them directly from single phase if you use a motor run capacitor to generate the 3rd phase. Not something to do if you aren't confident with your electrical knowledge but works fine on 3 of my machines.

Thanks Muzzer,no i am not that confident with electronics. I am just wondering if the mist sprayer will be toxic if so I will buy this https://www.hbm-machines.com/fr/p/kit-d ... ifications and connect to the relay board of my acorn ( need to check how to do it ).

Vincent

Thanks so i finnaly decide to go with flood cooling, I will buy a 240V water pump like this one https://www.aliexpress.com/item/3284077 ... Redirect=y

and I am wondering how I can connect it to my acorn centroid ? Can I plug directly to the relay board? ( it's only 100w but with 240V voltage )

inductive load is max 3A 125VAC, but I prefer to use external contactors with a 24V DC coil.

Uwe

Thanks,would you mind pointing me to some external contactor that would work ?
Regards
Vincent