pressing emax

[amadent]

With regards to investment and over expansion make sure you're not over mixing; also you could try using 1-2 ml less "special liquid"

With regards to temp you may consider increasing press temp 5-10 deg C and or increase the press cycle time 1-2 min at minimum.

i have 3-4 cases ready to press
i will keep you up to date on results
thanks for your time and advice

 

[dmonwaxa]

You're welcome and I wish you success. Do keep us updated.

 

[sixonice]

we have begun pressing emax with some great restoratins and some failures
is anyone having any problems pressing with computer generated waxups ?
we are scanning our full contours in our dental wings
the paterns are fabricated in a 3-shape wax printer

iam pressing in a zubler vario-press 300
this is my cycle- 200 gram
start temp 700"c
heat rate 60"c
final temp 915"c
hold time 24 minutes
press time 10 minutes
pressure - low
vacum level- 730mm
opening time :30

pressing printed wax patterns is 100% not the issue with the short pressings. i have several friends doing this very successfully. the problem lies in your pressing oven. your high (final) temperature is much too low. you should increase that temp to 940-945. you want to pull full vacuum for the entire program as well. other pressing ovens on the market need to be increased in final (high) temps. the ivoclar oven knows when the mold is completely pressed and finished through electronic pressing sensors and stops the pressing procedure, where as with the zubler you have to program a set pressing time. i like where your at with 10 minutes for the 200 gram ring though. increasing your final temp should help immediately.

 

[TheLabGuy]

I agree with Six here......
Your final temp on a 200 gram ring with large ingot should be 940 Celsius. Now if you want to use a 100 gram ring with a small ingot, you can lower that to 930 Celsius. Your short pressing are from not getting a high enough final temperature. Change that and you'll be good to go Their is fine line between having too much reaction layer and having short pressings, going to 940 will most likely press it fine but you may get a heavy reaction layer, adjust your final temp. accordingly. Hope that helps.

 

[amadent]

good morning all- thank you for the info
i cant explain how much all of your time and help means to me, my father and brother

i have few case ready to be sprued this a.m
since i do not have a 100gram ring
i am going to press in 200gram with a high temp of 940
will post pics after we devest the case
Greg Amendola MDT

 

[paulg100]

sorry if i missed something here, but those temps seem real high.

Im now down to 905c for final temp on me EP3000 on a 100 gram ring with press vest speed and im getting prefect results. Perfect fit and next to no reaction layer.

This was after my initial problems with a heavy reaction layer at the ivoclar pre-set setting.

using the same temp for mo, lt and ht all with spot on resluts.

 

[amadent]

got 2 complete presses with a hight temp of 940
crowns had a very heavy reaction layer - i think im going to lower hight temp a little
will post pics tonight when crowns are finished
thank you all agian for the help

 

[TheLabGuy]

got 2 complete presses with a hight temp of 940
crowns had a very heavy reaction layer - i think im going to lower hight temp a little
will post pics tonight when crowns are finished
thank you all again for the help

Lower your temp about 10 degrees C and you might be right where you need to be......hardly any reaction layer but presses all the way. I've noticed, unless you have a Ivoclar oven, this range is very precise within about 5 degrees C either way could make a difference.

 

[amadent]

here are a few or the 1st emax full contour press
thank you for the help

 

[Mike2]

I had the opportunity to do a ton of pressing at a large lab. With that said we tried everything to save time/money. I believe in Microstar, hands down best investment and Jensen gives great tech. support. The disposable plunger are great, no cleaning and they don't stick to ceramic. Also when de-vesting you can cut right through them. Valcon are cheaper, but I found their quality control unacceptable. The plungers varied in diameter and length. Speaking of de-vesting, I modified a Trinco parts blaster into a devesting machine. This was mostly with PTM's, but it could work with Emax. Very much like the Renfert machine, but cost is under 1000$. If anyone would like I can explain further, we did over 15 300g rings a day and I could load 4 at a time into the machine. With the exception of some touch-up blasting they would be done in 20 mins. and I figure it to save the lab 1 full time persons wages per year.
On the leveling caps, if you hold the edge of the ring open so the air can escape, no voids. I also did not use them but some of the less experienced techs. used to split rings daily because they wouldn't have the top level. On that note, drywall sandpaper works well for adjusting. My 2cents.

 

[TheLabGuy]

here are a few or the 1st emax full contour press
thank you for the help

Looking good Greg, glad to see you figured it out.

 

[amadent]

yes - pressing with high temp of 930'c
had to much reaction layer at the 940
will post more pics later in the week

 

[amadent]

just got my 100 gram rings
what do i have to do differently in my press program from 200 grams

 

[TheLabGuy]

The final temp, press and hold times are different from the 200 to 100 gram

 

[amadent]

thanks Rob,
i was told by ivoclar
lower high temp by 5'c (930 for 200)= 925 for 100 gram
lower hold time to 15 min (200 gram hold time is 24 min)
no mention of press time ?(200 gram press time is 10 min)

 

[TheLabGuy]

I agree with Ivoclar, other than I lower my press time to 8 mins on a 100 grams. Hope that helps.

 

[amadent]

will do -
Rob,asking because i dont know
why do you have to lower the press time, even though the ingot size is the same

 

[amadent]

well here are the pics
1st- wax done in dental wings software- forgot to take pic of the k-9
2nd -emax- layered and glazed
case came out ok-patient was happy with results
still hoping to get so pics from dr