Reaction layer

[NathanNever]

I did the first two e.max and have a surface that is removed with white glass beads already in the first phase of blasting. A part remains attached and remove after the passage in Invex. What puzzles me is the rough surface that remains, even at the margins that I have to go through the rubber and risk in a under contour. This roughness is normal? Also inside the crown, perhaps worse. Under the microscope 16x seems that the coating has crumbled like a little (this, however I've only seen it inside the crown). I used the debubblizer, the representative told me that some tech. use it. I think the mistake is the one. Mistake and should I look elsewhere for the solution? Help me to farvore. Thanks in advance. Oven ep 3000 brand new. LT 200g program.
Gian

 

[NathanNever]

I did the first two e.max and have a surface that is removed with white glass beads already in the first phase of blasting. A part remains attached and remove after the passage in Invex. What puzzles me is the rough surface that remains, even at the margins that I have to go through the rubber and risk in a under contour. This roughness is normal? Also inside the crown, perhaps worse. Under the microscope 16x seems that the coating has crumbled like a little (this, however I've only seen it inside the crown). I used the debubblizer, the representative told me that some tech. use it. I think the mistake is the one. Mistake and should I look elsewhere for the solution? Help me to farvore. Thanks in advance. Oven ep 3000 brand new. LT 200g program.
Gian

coating.... investment!
to farvore..... please!
errors...

 

[Brett Hansen CDT]

Don't use debubblizer. Also, use aluminous oxide to remove the reaction layer. What investment are you using? We have a new ep3000 as well. We get very little reaction layer. We use Microstar's HS investment. We burnout at 1600 degrees F for 40 mins on 100 gm rings and 50 mins on 200 gm rings. On our old ep500 we would get that rough surface you speak of before we turned down the temperature during the pressing about 15 degrees. Your new ep3000 shouldn't need any adjusting if it has been calibrated.

 

[charles007]

Never use debubblizer as Brett said... Try using Yet Lube for your wax patterns, as a die lube .. it seems to give bubble free presses using Ivoclar Speed Press or Microstar HS that I tried for 6 months, then switched back to Ivoclar, got better fits. The HS would loosen up as the weather changes, Ivoclar doesn't, even here in the South..
Using emax, follow the manual .. like using 1563 F burnout.. not 1600 unless your investment says that.. and calibrate burnout oven.. use glass beads first, then acid..its in the manual, and works faster than Al. I usally go back to the beads after acid to speed up the blasting, followed by aluminous oxide last.. Make sure you use 80 mic beads and correct al.. Using clean acid and hot water in ultra sonic speeds up the reaction layer.. 25-30 minutes.
If you follow the manual, you will have trouble free pressing for years with your Ivoclar oven just like many of us here on DLN..

 

[NathanNever]

Thank you! I will treasure your advice! I can not wait to reach new crowns. The investment is Ivoclar press speed. Temperature burnout 1562, 1h after the oven has reached again the 1562 after the insertion of the cylinder. thanks again.
Gian