Well, Here are the answers I come up with...
Question:Assuming the model was under-cured but it was sprued and envested correctly and the flask sat undisturbed for 3 hours before burnout:
Will it cause the envestment to break down resulting in a loss of detail?
Investment is not what is breaking down... in most Cases, it will be caused by left over debris. External defects are plaster related which can be over come.
Q)Will it prevent the complete incineration of the model?
Will some kind of residue remain in the cavity that prevents debris from escaping? Sometimes,yes
Will it stain the envestment? Sometimes
Will it discolor the casting?
Some discoloration that will usually pickle off
Will it cause porosity, pitting, cracking, brittleness, or incomplete fills?
Yes, It will … the effects are similar to Porosity, But it is due to left over debris
I currently don't think any of these are curing issues, but I'm not certain.
I have been up to 1600 for 10 hrs with Various investments on Items, I thought were fully cured and had left over debris in the casting. NOT outer surface issues, all internal. Repeated process with Longer cure time and added Vacuum rods to the pieces. Vacuumed using flat vacuum casting table with silicone seals, custom made attachments and collected debris,then cast into flask at temperature required and had perfect castings.Not all items require Vacuum rods to cast properly… some do.
I cast a secondary flask with Matching cured 2 pieces on the tree and no vacuum … 1 piece was perfect.. 1 had a small amount of debris.[/u]
It seems to me the main benefit of curing is the ability to cleanly file, sand, and rubber wheel the resin to remove print lines, supports, etc.
There seems to be a general consensus here that a cured model casts better than an under-cured model. Why?
Because it is part of the casting problem. If you don’t cure at all, which I would love to eliminate! you get lousy castings
If you are successfully casting with under curing, I would like to know what your process is