Coolant strength

[Muzzer]

Thanks, Dean, that makes a lot of sense. I'm actually using Castrol Hysol XF. When I look at the datasheet, there's an entry called "refractometer factor" that I hadn't noticed before. For this stuff, the factor is 1.1, so hardly worth bothering adjusting for.

In my case, I'm forever having to top it up with water to make up for evaporative losses - I guess that's the price you pay for a heated workshop. I just top it up to the level and periodically check the concentration.
https://www.thelubricationstore.com/...FDataSheet.pdf

[JAZZCNC]

In my case, I'm forever having to top it up with water to make up for evaporative losses -

Tell me about it, you should see the losses we get on our Hurco VMC. Between hot parts and a high-pressure coolant system, we are forever topping up the coolant, it's surprising how much you can lose just on the parts, even after blowing them off with air.!

But our biggest challenge and pain in the arse is contamination from the way-lube oil which is pumped to the linear bearings and ball-screws. It's a nightmare because while I can control the time the pump is on through the controls PLC I can't have it off for too long for the risk of killing the linear bearings so we get a film of oil on top of the coolant.

I'm trying to come up with a simple oil skimmer, so any ideas will be greatly appreciated.?

[Colin Barron]

Tell me about it, you should see the losses we get on our Hurco VMC. Between hot parts and a high-pressure coolant system, we are forever topping up the coolant, it's surprising how much you can lose just on the parts, even after blowing them off with air.!

But our biggest challenge and pain in the arse is contamination from the way-lube oil which is pumped to the linear bearings and ball-screws. It's a nightmare because while I can control the time the pump is on through the controls PLC I can't have it off for too long for the risk of killing the linear bearings so we get a film of oil on top of the coolant.

I'm trying to come up with a simple oil skimmer, so any ideas will be greatly appreciated.?

Jones and Shipman made filters for their grinding machines, could one be adapted? If you do have problems with coolant getting into linear bearings etc it may be worth doing rust checks using standard steel chips, filters and a petri dish. By checking the number of rust spots left on the filter it gives you a rule of thumb on coolant condition.