Curing in the microwave

[Robert Howle]

Do you know what temp the oil reached? I use enough oil 1.5 cups and is approx. 1.5" in depth, so it doesn't get to hot. Mine only got to 275 F after the third heating and no cracks.

Robert

[tim.yoshi]

Looks like controlling the temperature is critical here.
How this can be achieved? Maybe just trial and error. If you got cracks then you should use 2-10 time setting instead of 3-10. If cracks will appear again then try to lower the power of microwave.

So can anybody explain to me what do you mean under "mineral oil"? Is it equal to vaseline oil, paraffin oil, petroleum jelly, liquid paraffin? Quick search in local drug stores revealed that they got only such a thing like vaseline oil. But from the internet it seems that it is the same. Can anybody confirm?

[JewelryMonk]

Mineral Oil is also called "Intestinal Lubricant". It is the constancy of baby oil or something like that and found in most pharmacy stores.

[Robert Howle]

I am using "baby oil".

[noahbern]

Is there anyway to tell besides casting to see if it worked?

[ckl81]

I was doing my usual microwave curing Using the 10 mins heat at high temp. I am using the 8hrs burnout as usual. However my casting for the last 2 days was very bad as you can see. Is it my print is not fully cure in the 10mins microwave heat? Any suggestion on this? Thank you.
I will also going back to the UV box tomorrow and cast again. Will post result.

ken

[Mine Art]

Hello B9 microwavers
Recently I just microwave my model under water again ( not oil ) for 9 minutes (3 min , wait for 1 min x 3) the ring was hard,dry and no crack ,casted out perfectly

The ring must be very clean no uncure resins on the surfaces, I used the Methanol to clean for 30 seconds swirl in the container and then rinse under cold water for few seconds then go to microwave.

Mike N.

[Robert Howle]

At any pt did the water boil?

[Mine Art]

yes the 3 rd round for sure

[akgold]

Hello B9 microwavers
Recently I just microwave my model under water again ( not oil ) for 9 minutes (3 min , wait for 1 min x 3) the ring was hard,dry and no crack ,casted out perfectly

The ring must be very clean no uncure resins on the surfaces, I used the Methanol to clean for 30 seconds swirl in the container and then rinse under cold water for few seconds then go to microwave.

Mike N.

what power microwave are you using?
look on the back and see what the input and output power says for me.

[Metalcaster]

Hi
I just blew the picture up to see what the surface looks like... The surface is very bad... . the surface I get with the oil is smooth and no defects on rings.
other items do not always come out perfect , but rings seem to come out 98% of the time with oil mineral oil and baby oil was tried by Robert.
Not eveything labeled mineral oil is the same.there are many varieties. I only tested 1 variety.


Mine art , Can you post a picture of your rings so we can see the surface finish before you do any work on them?

[Mine Art]

The microwave is 700 watt
This one http://www.danby.com/en/CA/page.php?c=1 ... =14&p=1207
700 watts

I did not take a picture this time but you can see the other I did in microwave in the first page of this ( Curing in the microwave) section

[noahbern]

I am getting the same results as the picture above when use
mineral oil... Anyone had GREAT success with this method?
Really could use the help!

I tried 2 mins wait 10 2 mins wait 10 - terrible castings
i tried 3 min wait 10 3 mins wait 10 - cracks large and small parts
I also tried just bringing the oil to 225 ish and it didnt work... I use walgreens brand oil

[guyprotection]

Thanks for the info. guys

[Robert Howle]

Heat curing in the toater oven has given me consistenly good castings. Too many variables for me with the micro wave method. May be helpful to heat cure then micro wiht the oil to see if this improves the surface in some way. Will do some testing.

I have had no cracked prints with oven curing. Started testing by placing prints in a 200F oven then after only couple of min going up to 350 in 15 min. No cracks so far. It may be the case that excessive time in Iso contributes to cracking, not sure.

I only rinse for 10 or 15 sec with squirt bottle then into ultrasonic for about 20 min (just soap and water). Rinse dry then into 200F oven. Up to 350F for 1 to 1.5 hrs. NO Failed prints, since started this method. Satin Cast 20 and 5 or 7 hr burnout. Old school broken arm centrifugal casting machine. Melting with a large torch and using oxy and acetelyne. Please dont' tell me it's a dirty gas. I know all this , but I don't cast platinum in house.

Robert Howle

[danfurlano]

Just a guess - but since a microwave uses radio waves there are hot and cold spots. Something as small as a ring may be difficult to position correctly?

https://www.youtube.com/watch?v=kp33ZprO0Ck

[akgold]

That little video was very enlightening

[Robert Howle]

As I stated just heat cure and eliminate all the other variables.

[RobertH]

Hi Robert

How long do you keep at 200 before raising it to 350?

[Robert Howle]

only about 15 min.