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Re: Whitegold - Castings with emerald resin

Posted: Thu Jun 28, 2018 12:41 pm
by printcast
Only casting with emerald limits my experience with casting resins in general. 2 key factors I focus on are high temp (my furnace is programmed so I can't recall but 1450F for 4hrs seems correct) and air flow.

In the past investment breakdown seemed to be the issue that was solved with boric acid. Resin residue was the next problem that was solved with high temperature, time at the high temperature and airflow. Since those fixes there really haven't been bad cast.

Re: Whitegold - Castings with emerald resin

Posted: Thu Jun 28, 2018 5:27 pm
by rsaldivar
very nice

Re: Whitegold - Castings with emerald resin

Posted: Fri Jun 29, 2018 11:16 pm
by Christian K.
printcast wrote:Only casting with emerald limits my experience with casting resins in general. 2 key factors I focus on are high temp (my furnace is programmed so I can't recall but 1450F for 4hrs seems correct) and air flow.

In the past investment breakdown seemed to be the issue that was solved with boric acid. Resin residue was the next problem that was solved with high temperature, time at the high temperature and airflow. Since those fixes there really haven't been bad cast.



youre so right !

As i often said; so many people said : " Don't use boric acid".... we use it for years. no problems - great results, and no investment breakdown at the high temperatures.
Now a picture of last weeks casting under the microscope. the thickness of this part is 1.6mm. :)

Re: Whitegold - Castings with emerald resin

Posted: Sat Jun 30, 2018 3:15 am
by M-Williams
Christian K. wrote:
printcast wrote:Only casting with emerald limits my experience with casting resins in general. 2 key factors I focus on are high temp (my furnace is programmed so I can't recall but 1450F for 4hrs seems correct) and air flow.

In the past investment breakdown seemed to be the issue that was solved with boric acid. Resin residue was the next problem that was solved with high temperature, time at the high temperature and airflow. Since those fixes there really haven't been bad cast.



youre so right !

As i often said; so many people said : " Don't use boric acid".... we use it for years. no problems - great results, and no investment breakdown at the high temperatures.
Now a picture of last weeks casting under the microscope. the thickness of this part is 1.6mm. :)



Kudos!!

Re: Whitegold - Castings with emerald resin

Posted: Sat Jun 30, 2018 1:27 pm
by printcast
Christian K. wrote:
printcast wrote:Only casting with emerald limits my experience with casting resins in general. 2 key factors I focus on are high temp (my furnace is programmed so I can't recall but 1450F for 4hrs seems correct) and air flow.

In the past investment breakdown seemed to be the issue that was solved with boric acid. Resin residue was the next problem that was solved with high temperature, time at the high temperature and airflow. Since those fixes there really haven't been bad cast.



youre so right !

As i often said; so many people said : " Don't use boric acid".... we use it for years. no problems - great results, and no investment breakdown at the high temperatures.
Now a picture of last weeks casting under the microscope. the thickness of this part is 1.6mm. :)



That cast is perfect. Seems without boric acid at the temps I hit and the time it soaks the investment breaks down. Air, high temp, long soak to completely remove all resin. Boric acid to help investment hold together. One thing I'm going to try maybe today is a straight ramp to temp, soak at temp, then cast temp.

Re: Whitegold - Castings with emerald resin

Posted: Thu Jan 17, 2019 7:24 pm
by emild
Christian K. wrote:;) No everytime i have the chance to help, i do. :)



The keys are :

o microwave prints after 30 min in UV oven (in water) 3 times à 3min at 750 Watt.
o the burnout
o the boric acid ( 2% in the destilled water).


Burnout:

10C° per minute to 150 C° and hold 2 hours

10C° per minute to 450 C° and hold 1H30min.

10C° per minute up to 800 C° and hold for 5 hours ( yes this is the key, that NOTHING is left and everything burns out !! )

Down to casting temperature. :)

flask 500 C°

thick parts 1200 - 1250 C°
normal peaces 1250-1300
thin peaces 1300-1330 ( not higher, otherwise the surface will get damaged :)

good luck :D

Can you explain again the process after printing?

How you use. First microwave boiling? Or how?

Re: Whitegold - Castings with emerald resin

Posted: Thu Jan 24, 2019 5:42 pm
by Christian K.
Hey :)

Our treatment:

We have tow glass-container with isopropanol ( 99% ). One bottle to wash away the main resin parts, and one to wash away the isopropanol-resin mixture from the first botte.

    Put the bottle ( with models in it ) in the Ultrasonic cleaner for 30second.
    Put the bottle with the clean isopropanol ( with models in it ) in the Ultrasonic cleaner for 30second.
    steam them few seconds with the steam cleaner ( make sure to keep distance )
    dry them with air pressure
    Directly after drying put the models in a plastic cup ( microwave safe) with destilled water in it
    Boil them 3 minutes at 750-100 Watt - repeat that procedur 2 times - we found out that there are no disadvantages if you boil them longer - important is to let them cool of between the steps and fill the container up with destilled water. We made some tests with 5 minutes x 5 times = 25 minutes - Models came out flaweless. After 3 times of 3 minute-curing you are safe. Due the break between each step i think the Models boil 10 to 15 minutes in the hot water.
    After the boiling but the plastic cup with the models in it in a UV-oven for 1 hour. - we use a selfmade one with a can and LED UV stripes.
    Blow the models dry and wax them up.
    mix plasticast in 38/100 ratio with destilled water ( with 2% of boric acid in it - 5 litre bottle = 100 grams of boric acid powder
    after the flask were filled with the investment let them rest for a minimum of 4 hours, before the oven heat up. - we put them in the oven at 3pm, and the oven start with heating at 7pm.

I hope this help you!
Airflow is very important!

And we also recomment at first 2 hours at 100 °C, then 2 hours at 180 °C, and then the quick ramp up to 450. The first two steps are different.
The other steps as i wrote on the first page. :) we found out, that text or engraving came out much better when the investment is really really dry - thats why this additional step.

Re: Whitegold - Castings with emerald resin

Posted: Fri Jan 25, 2019 5:03 pm
by emild
Kristian

Thank you for for informations,
It is a really, really great


Thank you again

Re: Whitegold - Castings with emerald resin

Posted: Fri Jan 25, 2019 5:49 pm
by Christian K.
Your welcome - please write me if it worked out!
if you need something else write me a PN