Dry ice bath tub


KnifeDogs.com & USAknifemaker.com Owner
Staff member
I repeat my question, how does RV antifreeze compare to denatured alcohol for low temp? Denatured alcohol will achieve around -90F to -95F. I think acetone might get a tad lower, seems I've read -104F. Is RV antifreeze easier to handle? Last longer than alcohol with dry ice?

I read RV Anti-freeze comes in two ratings, a -50F and a -100F. That seems to be what's called the "burst point". I've not been able to find a spec on where it freezes solid. Freezing slushy would be ok for dry ice, but not if it froze solid. Looking at this: https://www.amazon.com/dp/B07MBQ5YX3/? that's rated at -50F, is that what congeals with dry ice? OR, does that require the -100F rated stuff?

Ken H>
I hav not tested the temp. My assumption is there is no reason I know of why the anti freeze would not get pretty close to the dry ice temperature. It should conduct the thermal (or cold in this case) just as efficiently as any other liquid. I have done several blades using dry ice and anti freeze and measuring the hardness change in the steel was right where it should be.


Well-Known Member
Tracy, Thank you for comment. On RV antifreeze did you use the -50F stuff? OR, the -100F rated stuff?

I think the question is more academic than anything, alcohol works just fine, and seems like it might be less expensive per gallon than RV antifreeze.