Help with resin please

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Help with resin please

Joined: February 6th, 2009, 1:45 am

July 30th, 2012, 4:46 pm #1

Hi guys
I have been casting a few pieces lately and I am having a problem.
First off, no problem with the masters or the Silicone RTV : I am using Alumilite brand Quick Set which gives me a nice pin hole free mold and cures in about 18 hours. That time is fine for me.
The problem I am having is with the Alumilite Super Plastic casting resin. It has a cure time of 90 seconds.
The result is it is almost impossible to get a pinhole free cast , especially with very fine detail. In high humidity it will try to cure while you are still mixing it.
Can any one recommend a 'slower ' resin that will yield consistent results that they have had good experience with, and are capable of filling in complex molds with out pressure or vacuum ?
thank you so much,
william tgcricu@yahoo.com
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Joined: July 13th, 2004, 1:39 am

July 30th, 2012, 6:14 pm #2

Is the best I have found. Their XXX Slow Resin has about a 10-15 min. working time. I have had no issues with it. It works great.

I prefer their RTV Rubber as well.


Gino P. Quintiliani

Field Artillery --- The KING of BATTLE!!!

HeavyArty's Showcase


Last edited by Gino P. Quintiliani on July 30th, 2012, 6:36 pm, edited 1 time in total.
Field Artillery --- The KING of BATTLE!!!

"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- George Orwell
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Joined: October 15th, 2010, 4:48 pm

July 30th, 2012, 9:08 pm #3

XXX slow is a Glenmarc (ex-Vagabond) designation, not Smooth-On.

Jon
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Joined: July 13th, 2004, 1:39 am

July 31st, 2012, 2:50 am #4

Yup, you're right, sorry. I used to use Vgabond products. They were great too.

It is Smooth-On Smooth-Cast 321. Great stuff.


Gino P. Quintiliani

Field Artillery --- The KING of BATTLE!!!

HeavyArty's Showcase


Last edited by Gino P. Quintiliani on July 31st, 2012, 3:02 am, edited 1 time in total.
Field Artillery --- The KING of BATTLE!!!

"People sleep peaceably in their beds at night only because rough men stand ready to do violence on their behalf." -- George Orwell
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FS1
Joined: October 4th, 2010, 12:45 pm

July 31st, 2012, 10:10 am #5

Hi guys
I have been casting a few pieces lately and I am having a problem.
First off, no problem with the masters or the Silicone RTV : I am using Alumilite brand Quick Set which gives me a nice pin hole free mold and cures in about 18 hours. That time is fine for me.
The problem I am having is with the Alumilite Super Plastic casting resin. It has a cure time of 90 seconds.
The result is it is almost impossible to get a pinhole free cast , especially with very fine detail. In high humidity it will try to cure while you are still mixing it.
Can any one recommend a 'slower ' resin that will yield consistent results that they have had good experience with, and are capable of filling in complex molds with out pressure or vacuum ?
thank you so much,
william tgcricu@yahoo.com
I've had the same problems. Perhaps a change in products is in order. If you live in TX, Texas Art Supply has a few brands. So does Michaels. Hobby Lobby, in my area, doesn't.
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Joined: April 29th, 2008, 7:22 pm

July 31st, 2012, 10:27 am #6

Hi guys
I have been casting a few pieces lately and I am having a problem.
First off, no problem with the masters or the Silicone RTV : I am using Alumilite brand Quick Set which gives me a nice pin hole free mold and cures in about 18 hours. That time is fine for me.
The problem I am having is with the Alumilite Super Plastic casting resin. It has a cure time of 90 seconds.
The result is it is almost impossible to get a pinhole free cast , especially with very fine detail. In high humidity it will try to cure while you are still mixing it.
Can any one recommend a 'slower ' resin that will yield consistent results that they have had good experience with, and are capable of filling in complex molds with out pressure or vacuum ?
thank you so much,
william tgcricu@yahoo.com
Bill - I also use Smooth-On 321. It gives plenty of pot life. For small or shallow items it is also good for bubble release.

The best answer to bubbles is a pressure pot. It is an investment but makes a huge difference. Check out Harbor Freight.

The only drawback is if you pressure cast, you need to make your molds under pressure. Sometimes the old atmospheric molds will have internal bubbles which pop under pressure.

HTH

Rounds Complete!!

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Joined: July 1st, 2005, 6:33 pm

July 31st, 2012, 10:38 am #7

Mike hit the nail on the head. Use a slow setting resin like Smooth-On 321 and a pressure pot!!

Something like this is easy to modify with a guage and a valve / quick connect.

http://www.harborfreight.com/2-1-2-half ... 66839.html

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Joined: February 6th, 2009, 1:45 am

July 31st, 2012, 2:43 pm #8

Thank you guys. Gino,Jon,Mike&Matt. Frank good luck!
So it is going be be Smooth On 321 and thanks to you guys
With the product name I was able to link to many tutorials on YouTube using 'Smooth On ' (and with a pressure pot)

best regards to all and thank you for your help!
william carls
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Joined: April 21st, 2005, 2:36 am

July 31st, 2012, 4:34 pm #9

Bill - I also use Smooth-On 321. It gives plenty of pot life. For small or shallow items it is also good for bubble release.

The best answer to bubbles is a pressure pot. It is an investment but makes a huge difference. Check out Harbor Freight.

The only drawback is if you pressure cast, you need to make your molds under pressure. Sometimes the old atmospheric molds will have internal bubbles which pop under pressure.

HTH

Rounds Complete!!
OK...not really a pot, but I have used the Smooth On 321 resin, and just placed my molds on the dryer while it was running. The gentle vibration of the dryer has (for me) been enough to get rid of bubbles in the resin while hardening.

Just don't let your better half catch you using the dryer, or they might put you to work!
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Joined: April 29th, 2008, 7:22 pm

August 1st, 2012, 12:43 am #10

Thank you guys. Gino,Jon,Mike&Matt. Frank good luck!
So it is going be be Smooth On 321 and thanks to you guys
With the product name I was able to link to many tutorials on YouTube using 'Smooth On ' (and with a pressure pot)

best regards to all and thank you for your help!
william carls
Bill - If you get the pressure pot (paint spray can), you only need about 20 psi. That will be more than enough to take care of all the bubbles.

Rounds Complete!!
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