eMax Ceram on Zirconia - trapped gases

DevonR

DevonR

Active Member
Full Member
Messages
514
Reaction score
77
I've been working at this on and off for weeks now. We are finally getting to the end of our Weiland Zeno porcelain supply and forced to switch.

First thing is I am using a Whipmix Pro 200 furnace. I would like to try to make it work if possible. If it won't, can anyone explain what the Ivoclar furnace does differently from a whipmix?

I have read this thread over and over and tried all of it:

http://dentallabnetwork.com/forums/...o-porosity-in-ceramic.12453/page-2#post-87291

Although my situation is different. I am getting trapped gases in the porcelain. I've tried every possible combination of lower the entry temp, where the vacuum starts, making sure the unit is getting heated enough, single stage, 2 stage.. yada yada yada........ I've got it to the point where the porcelain appears to be clear glass, but you can feel it on the surface, then you check under scopes and you can see it. I've attached a photo taken with the macro lens on an iphone.. best i could do.

File 2017-09-15, 10 15 34 AM.png

Is there anyone out there using emax on zirconia with a whipmix furnace and having success?

Any other thoughts? i just cannot seem to get rid of the trapped gases. i have about 3 different dentin bake programs that i've been modifying to try to get something to work and cannot. I also have 2 other whipmix furnaces I have tried and get the same results. Also note, the pro200 has never had metal in it ever. It is a ceramic only furnace.

Argen is our zirconia supplier, but that shouldn't be a factor.

I am using Ivoclar allround model liquid, have tried distilled, have tried 3 other bottles i have here but no difference.

I am using zirliner with their model liquid and following the ivoclar steps.

I have been in touch with various Ivoclar people and not really getting anywhere.

Any ideas would be appreciated. Thanks!
 
rkm rdt

rkm rdt

Well-Known Member
Full Member
Messages
19,542
Reaction score
3,288
Try gc lustre paste as your liner. I have the same porcelain and the same zirconia.

The lustre paste is a much better ceramic surface to fire to.

Is that a first or second bake in your pic?
 
eyeloveteeth

eyeloveteeth

Well-Known Member
Full Member
Messages
2,168
Reaction score
275
there is contamination somewhere in your process - just beacuse your furnace has never seen metal doesn't mean it's not contaminated. Do you sand blast your zirconia after sinter? are you ovens calibrated, what about your airline?

i hate to say this but are your brushes metal based? how clean are they really? do you see this in anything else you put in the oven?
 
DevonR

DevonR

Active Member
Full Member
Messages
514
Reaction score
77
Try gc lustre paste as your liner. I have the same porcelain and the same zirconia.

The lustre paste is a much better ceramic surface to fire to.

Is that a first or second bake in your pic?

1st bake

I have tried the gc lustre paste. I exclusively do this after i learned it from you... but now i'm following ivoclar directions in an effort to figure this out.
 
DevonR

DevonR

Active Member
Full Member
Messages
514
Reaction score
77
there is contamination somewhere in your process - just beacuse your furnace has never seen metal doesn't mean it's not contaminated. Do you sand blast your zirconia after sinter? are you ovens calibrated, what about your airline?

i hate to say this but are your brushes metal based? how clean are they really? do you see this in anything else you put in the oven?

I sandblast always. My brush is the Smileline 6-N.era The replacement tip is plastic.

I'll double check calibration and my airline. However, I fire other porcelains and do not have this issue... but maybe the ivoclar ceram is more sensitive?
 
rkm rdt

rkm rdt

Well-Known Member
Full Member
Messages
19,542
Reaction score
3,288
That looks too glassy for a first bake. Mine comes out like a sugar cube surface.
This is a low fusing porcelain. I'll post my temps in a second. I have the pp 200
 
rkm rdt

rkm rdt

Well-Known Member
Full Member
Messages
19,542
Reaction score
3,288
I sandblast always. My brush is the Smileline 6-N.era The replacement tip is plastic.

I'll double check calibration and my airline. However, I fire other porcelains and do not have this issue... but maybe the ivoclar ceram is more sensitive?
I have the same furnace and use the same brush with the same #6 tip.
 
eyeloveteeth

eyeloveteeth

Well-Known Member
Full Member
Messages
2,168
Reaction score
275
i was just going to say, looking at the photo it's WAY too shiny, seems very odd - definitely make sure that oven is calibrated - or that all teh sensors are in check.

Sounds insane but we just realized how far off our EP5000's were recently....6 were all calibrated at the same time and they have all shifted ever so slightly. (gonna be a good week lol)
 
rkm rdt

rkm rdt

Well-Known Member
Full Member
Messages
19,542
Reaction score
3,288
are you vibrating and condensing the porcelain?
 
DevonR

DevonR

Active Member
Full Member
Messages
514
Reaction score
77
I am over firing the porcelain on purpose to try to get rid of the gases. I was going up 10 or 5 degree increments.

Currently I'm running a clean to double check contamination in the furnace. Then i'll check calibration.
 
DevonR

DevonR

Active Member
Full Member
Messages
514
Reaction score
77
are you vibrating and condensing the porcelain?

one tap to draw water to surface after i build, then condense with a clean tissue. directly into furnace, no waiting around.
 
rkm rdt

rkm rdt

Well-Known Member
Full Member
Messages
19,542
Reaction score
3,288
my 1st bake in the PP 200
dry time 4mins
entry temp. 757F
rate 90F/min
hold temp 1382F
hold 1 min
table down 1382
cool 3 mins.
 
rkm rdt

rkm rdt

Well-Known Member
Full Member
Messages
19,542
Reaction score
3,288
I never condense or blot.
I let the model draw the moisture
 
DevonR

DevonR

Active Member
Full Member
Messages
514
Reaction score
77
my 1st bake in the PP 200
dry time 4mins
entry temp. 757F
rate 90F/min
hold temp 1382F
hold 1 min
table down 1382
cool 3 mins.


thank you. I'll try this after this clean cycle and a calibration.
 
rkm rdt

rkm rdt

Well-Known Member
Full Member
Messages
19,542
Reaction score
3,288
I am over firing the porcelain on purpose to try to get rid of the gases. I was going up 10 or 5 degree increments.

Currently I'm running a clean to double check contamination in the furnace. Then i'll check calibration.
you are boiling the porcelain,that's not contamination.
 
DevonR

DevonR

Active Member
Full Member
Messages
514
Reaction score
77
my 1st bake in the PP 200
dry time 4mins
entry temp. 757F
rate 90F/min
hold temp 1382F
hold 1 min
table down 1382
cool 3 mins.


when does you vac start and stop?
 
Al.

Al.

Well-Known Member
Full Member
Messages
3,573
Reaction score
904
Fire a tab separate from the crown.
or fire crown AND tab at same time to see if problem is in both layered zir and tab.
I layer zir with LiSi. More forgiving for me than ceram
 
Last edited:
Car 54

Car 54

Well-Known Member
Donator
Full Member
Messages
6,431
Reaction score
1,122
fire at tab separate from the crown.
or fire crown AND tab at same time to see if problem is in both layered zir and tab.
I layer zir with LiSi. More forgiving for me than ceram

Same for me, that's why I switched to ZI - F
 
user name

user name

Well-Known Member
Full Member
Messages
6,960
Reaction score
1,633
Does your porosity just show up on the surface, or is it evident as you grind down?

Blow out your firing chamber and get rid of any dust.

Remove and clean out your vacuum line. Make sure you have a trap installed in line.
 
Contraluz

Contraluz

Well-Known Member
Full Member
Messages
1,454
Reaction score
275
Any ideas would be appreciated

I haven't read through the whole thread but, try holding the vacuum throughout the whole cycle. Try the new parameters Ivoclar promoted a few months back.

I can provide more later if interested. Quite busy right now...
 
Top Bottom