Coolant suggestions...

[Jaff]

Hi All,

We run a small machine shop making mould tools and one off's etc, mostly in tool steels, but also some copper, aluminium and stainless on occasions.

We've just bought a new VMC to help things along and we're looking into which would be a suitable coolant to use. We currently run Castrol Cooledge Bl on our lathes and mills, which we are very happy with, ['Syntillo 22' on the grinding machines, which we are looking at changing... it seems to have a very poor tank life, despite being cleaned etc frequently!!] We wondered if we ought to look into something different for the VMC. There are occasions where our machines may not be run for several weeks at a time, but we do still try and run the coolant occasionally, as we have been told this helps.

What do you guys run or recommend, [that would be available in the UK]???

Graham.

[Mcgyver]

to start with, add an aquarium aerator - cheap and it will keep the smelly type of bacteria away - coolant needs to be oxygenated to deter them. add an aquarium UV filter and it will keep the grunge forming bacteria away. these are the two secrets the coolant company doesn't want you to know I'm going on 6 months of occasion home shop use but am shooting for the years I'm hearing some guys get.

[Jaff]

Thats a good tip, thank you... I guess thats why it's also important to skim the oil film off the top of the coolant as this would also prevent oxygen reaching the coolant??

We would struggle a little with the grinding fluid though as this operates through the old type of segmented settlement tank so it is effectively 6 or 7 seperate tanks, hence why we try to run it occasionally even when we are not using it.

What I was curious about was what type of soluble oil is often run successfully in VMCs?

Giving long tank life, good surface finish and long cutter life etc etc... A neighbouring machine shop uses Blaser and really rates it... but I'm not sure if they have run much else to compare it too!!

Anybody got an opinion on good coolants?

Grah.

[Glacern]

Hey Jaff,

We had problems with various coolants not mixing well with our very hard tap water. Synthetics would go bad quickly (totally stunk up the place), de-emulsify, and rust our mill tables. We tried using water purified by a reverse osmosis filter, but it only fixed the problem temporarily. Coolant would still go bad eventually.

Then we started using Master Chemical Trim 585, a semi-synthetic, and haven't had any problems since. Works great on everything including Titanium. We threw away our aquarium airstones and put all the air pumps in a box for storage. We simply don't need them anymore, and we don't even use the RO filter when replenishing our tanks. There are some equally good coolants out there from other brands, but Trim 585 is what works for us. Whichever brand you decide on, semi-synthetics are the way to go.

Also, the next time you switch out your coolant, consider adding a cleaner to your old coolant before draining it. Master Chemical makes a product called Whamex that cleanses your machine nicely. Add a gallon or two to your tank, run the coolant system overnight, and any crud or microbes will be loosened/dead by morning. Drain the tank entirely, using a shopvac to get every last drop, and then fill with the new coolant.

-Sol
Glacern Machine Tools
www.glacern.com

[Crapmuffins]

We use Q-CUT 251C from Qualichem where I work and it's the cleanest coolant i've ever used. You can blow it right off the parts and they come out of the machine virtually dry. It never leaves any and I mean any residue. I never have issues with tramp oil and tool life is amazing. Hope this helps.