Im trying a test

[BobCDT]

I think the Dekema will be more efficiency and thus lower temps will get similar results. We have them both and we can reduce the top temp of the Dekema 30-50 degrees to get like results.

 

[user name]

This dummys not done yet.

Ive checked with a couple mfgs of high temp measuring equipment, and the two that responded said 1540 is too high for their stuff to measure. Still waiting on the third that caters to the foundry biz. Also, the clay temp check folks say their hottest cones don't go that high.

Im going to run a similar test, but this time Im using much finer Zr samples thinking they will be more prone to distorting and giving a comparison.


I just designed a very flat coping and stuck it in the bottom of a 22mm puck, I added 6 support pins...1mm, 1.5mm and 2mm at the widest with a 2 degree taper. Hopefully they will mill successfully; if so, Im thinking I can cut them off and drill a small hole in either a porcelain firing peg or just a small block of Zr, and insert the pins so theyre parallel to the ground. I might mill the same out of a lower temp Zr and cook 'em hot and see if that gives me a visual as to the comparative temps in the two ovens.

I know most of you think this is unnecessary and if it looks good, its good enough. I like doing it and I want to know.

 

[user name]

I think the Dekema will be more efficiency and thus lower temps will get similar results. We have them both and we can reduce the top temp of the Dekema 30-50 degrees to get like results.

What ever the Dekema is doing is perfect. Im just trying to get the Mihm to reproduce it...Im close but I can see a difference. Ive been cooking Jensen XT and Sagemax NexxZr + together in both ovens. Theey both look great in the Dekema, and the sage looks good in the Mihm, but the XT in the Mihm looks a bit more opaque.

Bob, is there any way youre aware of to do a temp check in the Mihm?

(or are you just laughing at me ?)

 

[cadfan]

http://www.schupp-ceramics.com/index.php/en/firing-process-control-1/ptcr.html

 

[lcmlabforum]

http://www.schupp-ceramics.com/index.php/en/firing-process-control-1/ptcr.html

Page not found . . .
LCM

 

[cadfan]

maybe someone would like to bee in the underground try this or search for PTCR rings process temperature control rings

http://www.schupp-ceramics.com/en/d...ch-prozess-temperatur-kontrollringe-ptcr.html

 

[sidesh0wb0b]

maybe i am missing something,
why are you doing these tests?
are you having bridges warp a bunch? are you avoiding adding supports? what took you down this path and where the hell do you find the time to work on this? LOL

 

[user name]

maybe i am missing something,
why are you doing these tests?
are you having bridges warp a bunch? are you avoiding adding supports? what took you down this path and where the hell do you find the time to work on this? LOL

Re-cap...My Zr looks decent out of the Mihmvogt but great out of the Dekema. Im trying to figure if the Mihm is cooking a bit hotter or cooler than the Dekema.

 

[Tayebdental]

Re-cap...My Zr looks decent out of the Mihmvogt but great out of the Dekema. Im trying to figure if the Mihm is cooking a bit hotter or cooler than the Dekema.

Username is trying to prove with no doubt that the Dekima furnace has the best results when it comes to sintering zirconia, which I agree

 

[sidesh0wb0b]

Re-cap...My Zr looks decent out of the Mihmvogt but great out of the Dekema. Im trying to figure if the Mihm is cooking a bit hotter or cooler than the Dekema.

why not just pitch the Vogt and stick with the Dekema then? lol
lots of time for info you already know

 

[Thomas McInnerney]

The PTCR rings are sold in the US by Orton Ceramic Foundation. Orton has a blog on a product they recommend for the very purpose of this thread; https://www.ortonceramic.com/blog_direct_link.cfm/blog_id/63571

 

[MKan@t@]

I just spoke with a technician from Orton Ceramics who distributes PTCR rings. He wondered if I had heard of any mention on DLN of dental labs using Temp Tabs instead of PTCR rings.

He mentioned that some labs reported temperature results with PTCR rings that were WAY off of the expected value and this is due to not firing them at the recommended sintering parameters for PTCR rings....but instead using PTCR rings in batches of zirconia without regard to changes in peak temp and hold time depending on zirconia brand and manufacturer's recommended parameters.


https://www.ortonceramic.com/en/TempTABs/ It seems they are the more pricey option but can be used alongside a software to help you keep track of the temperature details for batches of sintered zirconia instead of simply the machine calibration itself.

These supposedly can be placed in the crucible with the zirconia you're firing and will give an accurate account of the peak temperature (and influence due to hold time) of each firing. This would mean that they've tested different brands of zirconia and have Temperature Batch Sheets for each brand they've tested. I'm not sure what brands have had testing literature developed for them.

Thoughts? Experience with Temp Tabs?

thanks for the help.

the weekend is upon us

 

[esamuelr]

Why would the brand of zirconia influence the results of the temp tabs? The temp tabs are measuring temperature inside the chamber in the specific position they are placed. Inside sagger, outside sagger, bottom level, top level, etc.

The specific brand of zirconia has nothing to do with what they measure. I can buy xyz zirconia that recommends a high temp of 1475 and sinter it at 1550 if I want to.

The temp tabs would be used after a calibration or at the beginning of the oven life to measure the heating accuracy of the oven to my chosen temperature of 1550.

The specific zirconia should not matter at all. The accuracy of your ovens calibration at the inception of use for the temp tabs would be of greater importance to gauge and control proper readouts.


Last line in there blog bout Temp Tabs" The best time to begin using the TempTAB is immediately after a calibration or at the start of using a new furnace to establish a benchmark for future comparison. "

 

[JMN]

Why would the brand of zirconia influence the results of the temp tabs? The temp tabs are measuring temperature inside the chamber in the specific position they are placed. Inside sagger, outside sagger, bottom level, top level, etc.

The specific brand of zirconia has nothing to do with what they measure. I can buy xyz zirconia that recommends a high temp of 1475 and sinter it at 1550 if I want to.

The temp tabs would be used after a calibration or at the beginning of the oven life to measure the heating accuracy of the oven to my chosen temperature of 1550.

The specific zirconia should not matter at all. The accuracy of your ovens calibration at the inception of use for the temp tabs would be of greater importance to gauge and control proper readouts.


Last line in there blog bout Temp Tabs" The best time to begin using the TempTAB is immediately after a calibration or at the start of using a new furnace to establish a benchmark for future comparison. "

I'd wager that there is a minute amount of heat absorption speed differences with various blends of zirconia. The amazing differences we can see between currently available products and those of 10 years ago are a result of lots of fiddling with the molecule and it's crystallization process .

Think of it like cooking a loaf of wheat bread vs a loaf of white. They can both go into the oven at the same temp, but there will be thermal variances in their surrounding areas as a result of how fast they can absorb the heat, there will also be variances in how much power is used to heat their two differing compositions, and the wheat will need far longer to absorb sufficient heat to the interior. But they both are, after all, mostly just flour and water.

 

[esamuelr]

I agree that the make up of a zirconia will affect its esthetic but accuracy of thermocouples, control electronics, number of heating elements, size of the chamber, insulation in the oven, insulation material, variances in your power supply, will all have a greater effect on the result and more importantly the consistency of your sintered results than the formulation.

As you said it's flour and water, but a better oven is less likely to burn the bread and cook it evenly for the first and last loaf of the week.

I should add that a dekema is like a Mercedes. It costs a lot more for an oil change than a Chevy.

 

[JMN]

I agree that the make up of a zirconia will affect its esthetic but accuracy of thermocouples, control electronics, number of heating elements, size of the chamber, insulation in the oven, insulation material, variances in your power supply, will all have a greater effect on the result and more importantly the consistency of your sintered results than the formulation.

As you said it's flour and water, but a better oven is less likely to burn the bread and cook it evenly for the first and last loaf of the week.

I should add that a dekema is like a Mercedes. It costs a lot more for an oil change than a Chevy.

Maybe I should have gone with cookies... Ummmm. Coookieees...

I agree, there shouldn't be that much difference or there would likely be seen variances in sintered zirc from the same issue. Just couldn't leave well enough alone as there is a difference possible.

 

[CoolHandLuke]

if youve got two leftover pucks that cant be used and have the same shrinkage factor put them in. measure diameter.

will a full size puck fit in either of these machines?

 

[user name]

I agree that the make up of a zirconia will affect its esthetic but accuracy of thermocouples, control electronics, number of heating elements, size of the chamber, insulation in the oven, insulation material, variances in your power supply, will all have a greater effect on the result and more importantly the consistency of your sintered results than the formulation.

As you said it's flour and water, but a better oven is less likely to burn the bread and cook it evenly for the first and last loaf of the week.

I should add that a dekema is like a Mercedes. It costs a lot more for an oil change than a Chevy.

We know each other, and I know that you know your stuff. How ever...I need to correct you. The Dekema is like a Mercedes, but it doesn't cost more for maintenance. The troubled unit you know I had was simply that...it had issues. The replacement oven is top shelf. Not a single issue. If Id known that this is how they are I would have bought another one rather than a Mihm. I just cant get that thing to give results that look the same as the Dekema.

 

[JMN]

The PTCR rings are sold in the US by Orton Ceramic Foundation. Orton has a blog on a product they recommend for the very purpose of this thread; https://www.ortonceramic.com/blog_direct_link.cfm/blog_id/63571

Greetings Earthling! Welcome!

Usually I'd get to say this in the introduction area, but you jumped straight into the pool with your toys.
Have fun and don't forget the snack bar over near the fence has a special on apple flavoured twin pops today.

 

[user name]

Oven calibration problem solved. Digital micrometer. Orton temp tabs. Cook the tab. Measure the tab. Look on their chart for a temperature correlation.
Caliper...$100.
TempTabs...$48.
Accurate oven...priceless.