To FIERY and SGC, mostly...

This last time, I did chill - but not 'freeze' - the spray cans. In cooler weather, room temperature seems acceptable.

Agree, invert the can so the pickup straw is out of the liquid, and spray off propellant. When that hiss eases to a sigh, release the nozzle, shake it again, invert and spray off propellant. Two to four times through this is usually sufficient to get only a slight suggestion of a hiss with the can inverted. The can cools, but not to a freezing temperature.

After that last shake and propellant release, I turn the can upright quickly, and punch the upper rim with an awl. It is a good idea to avoid sparks, agreed? I tap the awl with a rubber mallet... Leave the point in the can as a bung, and gradually ease it out of tight seal contact. Yes, it will hiss again. Limit that until it settles out completely.

Withdraw the awl, and punch another hole next to the first one, then go to the opposite side of the rim and punch three holes close together. The first two serve as vents, when you pour the liquid content out through the other three. I have a glass jar of sufficient volume, with a 'good' sealing cap, handy during this process...

Pour the liquid from the can into the jar and close it up fairly well. You'll need two John Deere spray cans to brew up a quart of ~33% ether fuel.* So, most likely, you'll be milking another before you blend up the actual fuel. Mix the fuel ingredients as soon as safely practical after milking the pressure cans - Ether will evaporate through most ordinary cap seals. Transfer the measured blend into a metal screw cap can. If you have vent and feed tubes soldered through the cap, there's minimal ether loss in loading your bulb, bottle or syringe for fueling you model.

Seal the metal can cap threads with plumber's teflon thread seal tape. It does a great job.

* - The JD cans list content as 7 fl oz, 80% of which is di-ethyl ether. If measure is by volume rather than weight, that means 5.6 fl oz ether per can. Two cans yield a bit over 11 fl oz, or around 35% ether in the blend. I've presumed the 'other' liquid is similar to a clean kerosene, and not had reason to suspect anything harmful after checking engines run on fuel so blended. That make it easy to factor the other fuel elements. The 11.2 fl oz of ether occupies 14 fl oz of the fuel volume. If a 25% castor blend is intended, that's 8 fl oz per quart, totaling 22 fl oz for Ether and castor. The remaining 10 fl oz is for the kerosene (and DII, if used.) This example fuel is 35%E, 25%C, thus 40%K(w/small % DII if used.)

For the metric users, it should be even simpler if a reasonable lab graduate is at hand: percentages read more or less directly from the markings.

For USA diesel users, there should be some sort of farm or recreational equipment store, station or supplier within reasonable distance which carries John Deere goods. That should make a handy source for the JD Starting Ether.