For help!Sintering furnace

[Simon_Vincismile]

Hello, everyone！ My customer asked me a strange problem about his sintering furnace. He told me that his furnace must preheat before sintering and keep above 300C, otherwise, the zirconia would be opaque. He wants to know if there is any solutions for his problem (except buy a new one)
The heating element is MOSI2 and there is a glass layer on the surface. The glass layer would crack if the temp below 300C, and he though that is the reason to preheat. Replace new heating element could solve this problem? I'd like to know your opinions about it.
(He didn't know the manufacturer and here is the furnace picture)

 

[CroatiaDental]

Sounds like the zirconium gets too hot or too cold.
Opaque eff can be caused by either a too hot or too cold furnace.
Depending on the firmware it can be that either the furnace starts at 300 meaning it reaches desired temp (1500celcius) for example then keeps it for a lower amount of time than its set up on the program if it is based on temp and not on time. (the programed sintering is not correct, check and change)
If the program is set up good for the zirconia block that he is using... his heater then takes too long or doesent reach the desired temp in forseen amount of time causing it to keep it at the desired temp for a lower amount of time and it doesent sinter properly.
Instead of preheating he can try and set the amount to keep at (1500celcius for example) for 1 hour longer as heat. Beacause heat increases exponentially it reaches 1500 much faster.
Also keep in mind some block have different temps based on number of crowns in a bridge. Probably due to grain size.

 

[mmbh]

Hello, everyone！ My customer asked me a strange problem about his sintering furnace. He told me that his furnace must preheat before sintering and keep above 300C, otherwise, the zirconia would be opaque. He wants to know if there is any solutions for his problem (except buy a new one)
The heating element is MOSI2 and there is a glass layer on the surface. The glass layer would crack if the temp below 300C, and he though that is the reason to preheat. Replace new heating element could solve this problem? I'd like to know your opinions about it.
(He didn't know the manufacturer and here is the furnace picture)

I have one of these inexpensive furnaces as a back up. Worked fine for awhile but If I use it now I have to run a clean cycle after every sinter cycle to regenerate the heating elements. Otherwise they don't come out right. Not sure why it does that and the company I bought it from doesn't know why either. Its a pain but its a backup.

 

[RileyS]

I’ve been rocking two of those suckers for almost a decade now with zero problems in one and a current slight issue in the other…but never needed new heating elements or anything. Basically what I’m saying is I have nothing to say of any worth to help you out. Sorry broski