Stupidly simple solution to the form wash evaporation woes


#21

Your solution to the isopropyl alcohol evaporation problem is a good one. Thanks for sharing with us. I thought I would present my solution here in your thread.

I decided to look for a container that the tank would fit into. This army ammunition can from ebay is doing the trick for me.

I had to replace the seal with a new piece of 1/4" rubber so it could hold back the 0.7 psi of vapor pressure.

The ammo can lid is 15" by 12". That vapor pressure would result in a force on the lid of 126 lb. It really adds up for a container this large.

Cheers
Dave


#22

Isnt’ the evaporation happening anyway, just contained?


#23

It happens until an equilibrium is reached between evaporation and condensation. That’s the concept of vapor pressure. If the Form Wash is contained, then there will be much less evaporation, as the vapor can’t escape and an equilibrium is reached quickly. On the other hand, with an uncontained, unsealed Form Wash, the vapor can escape and there will never be such an equilibrium, the IPA will just continue evaporating until it is gone.


#24

Do you end up with a film of condensation coating the outside of your Form Wash?

Nice case BTW; guess the ammo box is also handy if your Wash spontaneously explodes.


#25

Only the tank from the Form Wash is in the ammo can. I have not noticed any condensation on it yet. If there is some after a longer period of time I will report back.


#26

Opened the ammo can first time today after printing a part. It has been 18 days. You will probably not be surprised to hear that there was zero measurable alcohol loss.

Cheers
Dave