Thanks.
Al's comment to keep as a solid model is helpful.
Pronto's also helpful. I could trim accessable margins and paint spacer (ie. for Variolink II),then duplicate.
Pour in refractory.
Degass.
Then soak die in distilled water to keep die from wicking off the liquid from the porcelain (this was from Al-I think).
Stack.
Give longer drying time (10 min) and fire at a slightly higher temp [these ideas came from a previous thread, comments by Al and sixonice].
Devest. 90% "saw-out" the remove remaining investment with round bur and lower pressure blast with glass beads (some of this from Al, previously).
Use "add-on" porcelain as needed (this was a previous thread),with proper support.
I have "gleaned" this much. Does this seem correct? [as a cookbook approach]
Thanks again for your input(s).
Your first bake is a wash bake to seal the model.
In areas that have more space like wider interproximals you may need extra bakes or the porc will pull away and you may have voids underneith or in the tissue area.
With veneers on ref. models it is WAY better do several extra bakes rather than large bakes for multiple units (singles are a cake walk). You do not want to have to recontour and polish after you devest and it is a pain to contour over built veneers on a model. Try to build your interproximal contours,separation,embrasures rather try to cut them in. Be very exact with your buildup, you wont regret it.
I would not saw them but use a diamond disk. The exact same way you seperate dies that have margins that touch each other. After you glaze take your ultra thin diamond and score the glazed incisal embrasure (similar like a glass cutter does and cut our model from underneith to the gin embrasure and just very lightly score the porc. You created the two spots you want the break to start. Then continue to section it. If you have built your connections thin it will just snap or fall apart nicely. If not hold your breath and snap it. 99% of the time this worked perfectly for me but only on cases that were min preps where the dr had not broke the contact.
If the contact is broke you need to seperate the model in that area. You nont need several dies but only dies for veneers that have broke contacts.
When you snap the glazed veneers thay will often be irregular or one may be slighty over on to the other tooth that is where you use your low fusing add on or your place it type of material to make a temp die.
I just used a low fusing porc. I think you need to stay below 1350 F. I never used support for addons but you will for shade stains.
I always soaked my model for 1 or 2 min usually till it quit bubbling. Too long and you just shake it off and give it a minute.
If you build 6 units it takes some time so you may have to keep rewetting your model with your brush or set the botton in your water for a cuple of seconds. I dried it under the furnace till it turned white.
If you err on firing temp do it on the hot side if its under fired its a redo, a million small bubbles and milky or no trans.
You may not need a hotter temp but a longer hold time you have to do a few doxen of cases to get it figured out.
As far as die spacer the kind you put on refractory I used sucks, I used to releave the inside with a rounded tiped diamond for cement space.
If you have to mask out discolored teeth you may try to use a base of really white porc then put color on top of that.
I havnt revieved what I posted above so my grammer etc is prob terrible.