Staying cool and dry

I think we can all have enough self-awareness to agree that the Tormach PCNC 440 enclosure was not really designed for aggressive flood coolant. Especially if you upgraded your pump to a larger pump & reservoir and a larger manifold with more nozzles. Luckily my toes have been kept well lubed and cool especially on my last job which had a 2” circular pocket which simply re-aimed the coolant straight onto the doors, yikes what a mess! Unlike tiny pinhole leaks in your Glowforge’s exhaust, coolant leaks are immediately obvious. Despite a rubber diamond plate mat in front of the mill, the floor is becoming slippery and wet, as the coolant splashes onto the door and runs out the front. I had a temporary workaround with some polystyrene sheets stuck under the doors, which kind of worked but made the mill doors hard to open and close. So I designed and installed a new coolant diverter. So the idea was to use laser cuttable over head transparency (which as far as I can tell is PETG). It is much thinner than what many are using for face shields (deliberately, as it needs to seal against the door as you will see). I just printed them in PLA (because if they fail, who cares) and the holes in the model are M3-tapped (PLA taps just fine). The M3 cap head stainless screws I use on the front to mount the sheet are like 3-4mm long and the ones from the acrylic side are maybe 6-7.5mm long. Do they need to be stainless? Who knows, coolant I know has corrosion inhibiters, but I had an assortment of cheap stainless ones from china on hand. The way it works is the PETG sheet extends above the block and flexes against the door providing a good friction seal. As you can see in the included movie works pretty damned well. The design has little extensions that go onto the same screws for things like the hinge plate or center door panel to prevent the main sheet from distorting due to different levels. I figure the total cost is around $3, so given the savings in shop towels is a good bargain. All the screws are M3. And as for the laser template, I was limited by the sheet material I could get so that’s why it’s as narrow as it is rather than the door width.
I also found coolant was splashing out under the control box for the ATC so there is a cut file for 1/8” acrylic to go under there. It doesn’t seal against the box (so you can level) but seems to have eliminated 99% of indirect splash outs.

coolant splash guard for 440.zip (46.7 KB)

12 Likes

Oh and of course there is one on the right side door too, just wasn’t there for the first test.

I will note that is only 1/3 of the coolant volume so it can make a giant mess!

1 Like

Nice save with the guards. What type of coolant are you using? Sticky mess huh?

Qualchem Xtreme Cut 251c. It’s really weird when you mix it (into distilled water at 20:1) it’s a dark brown oily substance and when you mix it the whole mixture turns milk-white.

Just like your engine oil when you blow a head gasket. As you say, you add it to water, not the other way around. Our coolant rep would roll his eyes when he saw guys pouring concentrate into a pail and then aerating it with the garden hose from 3 feet away. Big pail of foam which makes the coolant tent to get rotten way faster. The synthetics are way better in regard to resisting becoming rancid.

And I have a tramp oil pillow (some day I will use a skimmer I guess) which prevents the tramp oil film from trapping anaerobic bacteria beneath it which rapidly becomes rancid. Xtreme-Cut also doesn’t have a terrible odor (since this is in my house, that mattered)

1 Like

Here is the two-door test

6 Likes

I see what you have done here. The bent edge maintains firm edge contact with the door. Clever.

And the coolant has a pretty high surface tension so doesn’t sneak under…

Excellent!