I have done some casting before, all with no degassing and no pressure and the inevitable bubbles resulted in maybe 1 of 6 casts being usable.
I am now considering getting a pressure pot and dual purposing it for vacuum and pressure. Everything I have read to date (not that long) has seemed to indicate that you want speed when doing the vacuum and then again the pressurisation.
Now my questions are:
Is this only because of the curing time of the resin used? - I can understand this if one is doing larger scale castings and you want to be done with it asap.
Would a longer cure time resin allow for a slower vacuum to be created and then a slower buildup of pressure?
Or is there some chemical reaction in the cure process that is sped up to a noticeable degree due to the vacuum / pressure?
If you had to pick only one, either vacuum or pressure, which is the better option?