Is cold IPA just as effective?


#1

Hi all,

Does anyone know how cold temperature might affect the effectiveness of IPA at dissolving resin?

I’ve always washed my parts at room temperature, but the 3L wash kit is very large (apparently it fills to 10 gallons, even though the max build volume of the printer is around half that).

I’m considering keeping it outside. With winter here, that means it’ll be subject to freezing temperatures. Over the year it might range between -15°C (5°F) and 25°C (77°F), with much of that being around 0°C (32°F) in the winter months.

I’m not worried about the IPA itself freezing (I think pure IPA freezes around -89°C / 128°F) but I’m uncertain how it might affect wash times. Has anyone rinsed parts in cold IPA?

I also realize subjecting parts to sudden temperature changes (e.g. straight from printer into a sub-zero bath) could induce some internal stress.

Appreciate hearing your thoughts on this.


#2

Very interesting point, on the Form Wash doesn’t say that the IPA is heated, but as we know everything slows down in the cold.


#3

I imagine both the resin and the alcohol will become less viscous. The resin could potentially freeze, so solubility will slow down considerably.

One thing I’ve wondered about is how much resin can be dissolved in IPA, i.e. how that depends on temperature. Perhaps it does not depend much on temperature.

One downside to storing your IPA outside is the potential for wind and evaporation. Hopefully you can contain the IPA in a wind-free box, to limit evaporation.


#4

My form wash is in an enclosed cabinet but basically at outside temps. I don’t have any quantitative data, but it’s been working fine for me.

I notice more of a performance hit with cold DPM than anything else…but I also haven’t tried washing in heated IPA so who knows.


#5

I fixed that for you. I agree with the rest. :slight_smile:

At colder temperatures, the molecules have less excitation (AKA “Brownian Motion” for those of you who are Hitchhiker’s Guide fans). What makes the resin and alcohol mix is the motion of their respective molecules.

So colder temperature resin and IPA will slow down the cleaning process. Just like washing dishes in hot water works better than cold.