We need to run our sawmill. And part of our sawmill has a bottle of water that drips water onto the blade. This keeps the blade lubed and cool.
We have a lot of days where the temperature hovers just under freezing. It seems like it would be wise to mix a little something into the water to keep it from freezing.
Salt would encourage rust. And I am concerned about too much salt on the soil. So I want to avoid salt.
Isopropol alcohol is a poison. Ick.
So now I'm thinking about something like cheap vodka. But alcohol seems to always lead to terrible problems. I suppose we could try to put something in it that would be fine for the blade, fine for the soil but people would not want to drink it. But it would require a LOT of alcohol to keep it from freezing at something like 25 degrees.
Maybe the thing to do is to somehow set up a thermos full of warm water. Maybe insulate the line to the blade a bit.
Plus, as I am typing this, I am getting concerned about human discipline. It seems like something will happen and somebody will try to fix something and then an hour passes and stuff has frozen and broke. Then it needs to be repaired. And then we end up fixing this stuff ten times per winter.
Maybe this is something where we need some sort of warming cable. This is, after all, an electric sawmill. And maybe, as long as the sawmill is connected to electricity, there is some warming tape wrapped around stuff.
I just had a thought: if we have something like a thermos with warm/hot water in it - and it runs into an insulated tube .... the current design is that the water keeps running until you shut it off. It is possible that we could set it up in such a way that when using the insulated tube, there is no shut off. It has to dribble constantly. That way, the only way to get it to stop dribbling is to disconnect the thermos. So if somebody forgets, it will just end up pouring all of the warm water on the ground and nothing freezes.
If you want to go with ethanol, I would suggest going with methanol denatured ethanol. Lowes sells a gallon for about $16 which is far less than you would ever pay for vodka especially when you consider vodka is only ~40% ethanol. The freezing point depression of water mixed with other things has been well studied, so there are plenty of charts that let you know how much would need to be added to get the desired results. For example, in the linked chart if you want your solution to freeze at 25F you'll need a 10% ethanol solution, and a 20% ethanol solution drops the freezing point down to 15F.
For my dad's sawmill during winter we simply stop running water in the winter. When it's below freezing we've found that the blade never gets so hot that it's a concern. This is a ban-saw mill so I'm not sure if it would be different for your circle saw mill.
Another thought is beet juice. We run fluid in the tire tractors to add weight to the rear end, beet juice in tractor tires is a pretty common practice for farmers here. The beet juice has a high enough sugar content that it doesn't freeze in the winter. This may work for your sawmill as well and would be much cheaper than hooch, without the potential side issues.
I try my best to not put GMO's in my body but I have rationalized that they are OK for filling tractor tires and providing the lube for my chainsaw; much better than the super toxic alternatives in my opinion.
water bottle with heat tape wrapped around it might work, just plug in the tape awhile before.
Ethanol is a solvent too, dripping that onto a blade would probably do some damage if there are greased parts. Also flammable at a high concentration which isn't good around sparks and sawdust.
I use that coolant in my diesel at about 90% coolant since it is much better than ethylene glycol and recommend switching all vehicles over to it when changing coolant. (I will not go over why I use 90% instead of 50/50mix in this post.)
But... I like the idea of using an insulated container to hold heated water for when it is in the temp range that water will freeze but its not cold enough to cool the blade. Checking the blade temp with a IR thermometer several times and you might find that a short 1-3 second pause between passes might be enough to keep the blade from over heating.
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