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Question About A Resin Casting Brand


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Hi everyone. Is there anybody out there who has used a resin made by Bare Metal Foil called Polytek Easyflo-60 polyurethane casting resin? If so, is it easy to work with as I am new to casting and want to buy a user friendly resin. Any help would be appreciated. Thanks, Don B

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I've been casting my own resin parts for three years now. Everyone else who does will give their two cents worth, but I started with Micro-Mark's resin products and continue to use them today. Buy their starter kit as it comes with everything you need...rubber, resin, mold release, mixing supplies, clay.

Both the rubber and resin are 50:50 mix, which is much more forgiving and easier to blend for novices than the 10:1 others have. You need a scale to mix 10:1.

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Don,

I seem to remember that Bare-Metal Foil had some casting products but I've never used them. As Marc said though, everyone has their TCW. Me, I use Alumilite products exclusively. The resins are 1:1 by weight or volume but most of the RTVs are 10:1, but nothing that can't be handled even by a beginner. Also as Marc said, you would need a good postal scale that measures in both pounds/ounce and kg/g. I got mine from Office Depot for about $30.00 (actually on my second one, first one was ruined by spilled resin). Also for those resin casters that are trying to find good mixing cups. If you go to SAMS CLUB or COSTCO you can pick up small condiment cups by the case (500 per case) for around $6.00 and clear cocktail cups (250 per package) for about $10.00. Great for mixing resin and small amounts of RTV.

Chris.

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Thanks for your input. I went to BMF'S web site and got this info. Is the mixed viscosity of 60 cps good? :P

PHYSICAL PROPERTIES:

Mix ratio, by volume 1A to 1B

Hardness,Shore D 65

Pour time, 1 lb. Mix 2 ½ minutes

Demold time 15-30 minutes

Color, cured White

Mixed viscosity 60 cps.

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Thanks for your input. I went to BMF'S web site and got this info. Is the mixed viscosity of 60 cps good? :P

PHYSICAL PROPERTIES:

Mix ratio, by volume 1A to 1B

Hardness,Shore D 65

Pour time, 1 lb. Mix 2 ½ minutes

Demold time 15-30 minutes

Color, cured White

Mixed viscosity 60 cps.

Especially for a beginner, I would look for a resin with a longer pot life. 2.5 minutes is not long to mix, pour and work with. The CR-600 I get from Micro-Mark has a 7 minute pot life.

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A Shore Hardness of D65 is fairly stiff but not as stiff as I like it. I like resins with a D80 or higher

Pot life of 2-1/2 minutes is okay but you can extend the pot life by placing Part "B" in the fridge for about 5 hours. The chilled Part "B" will give you an extra 30 to 60 seconds of pot-life. BTW...pot-life begins the minute you mix the two parts and when they start to "kick-off".

Demold time is a bit too high for me.

White is fine color

A CPS of 60 is about right. Water has a CPS of 1 and Chocolate Syrup has a CPS of 25,000.

Now I can just see the questions about bubbles coming any time...right Marc?

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Now I have been using the Alumilites resin, but have only about 30 seconds to mix and then sling it. The micro mark stuff I have been eying now. When I place my next order was thinking of trying the 7 minute one. Any pros/cons or tips and tricks to go with it?Thanks.

the micro mark resins are water thin so make sure your two part molds are tight. I haven't tried the 7 minute yet but I like the cr-300 and the cr-900 resins. The 1 to 1 rapid rtv mold rubber is really nice.

Ray Carey

rtcarey11

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  • 9 years later...

I have some Micro Mark CR-300 urethane resin I've been using for over a year.  Recent castings have tiny (less than 1 mm) bubbles just below the surface of the bottom of the piece, i.e., next to the detailed part of the slush mold.  I've squeezed the resin bottles to get as much air out as possible.  Is there any cure?  Sanding causes the bubbles to expand and once their surface is open I have not been able to fill or seal them.  BTW, I greatly prefer CR-300 to any alternative I've tried:  little smell, easy to work (a little softer than model car styrene).

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http://www.reynoldsam.com/phoenix/

https://www.smooth-on.com/tb/files/TASK_8_TB.pdf

https://www.smooth-on.com/tb/files/SMOOTHCAST_325_326_327_COMBO_TB.pdf

https://www.smooth-on.com/tb/files/MOLD_STAR_15_16_30_TB.pdfhttps://www.smooth-on.com/tb/files/MOLD_STAR_15_16_30_TB.pdf

I try to use Smooth on products.  When I need something I just drive there and buy product fresh off the shelf.  I use their Task 8.  Once cured it will become chemical proof and will withstand a great amount of heat.  It won't melt in your mouth or your car.  I don't really know a lot about paint but I think some can get hot and damage some resin products.

 

https://www.polytek.com/sites/default/files/PTFlexSeries_New-Improved_TechnicalBulletin_Polytek_0.pdf

I only wish that Smooth on had a product like the Polytek Flex series for making tires.  I have used the 60 and 70 for tire making but it is quite expensive, but it cures pretty quickly.  It also does not like the silicone that I use either.  Compatability issues can be costly too.  I only wish that some products were packaged in smaller containers

Edited by Greg Wann
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I myself started with alumalite  then smooth on. They are both good and very close to how they  work for learning I personally think I like the alumalite for a couple reasons.  The biggest is cost . 

You can get the large kit from hobby lobby and use the 40 % off coupon that is very hard to beat to start out I also think its a little more forgiving to learn with the combination of things in the kit the instructions are very cut and Sri. And Carol at help desk is very informative if needed. Now if you make it to the point of any kind of production I really like the smooth on. Things happen a little fast pot life cure time etc. And I had a learning curve to make the switch. But having an outlet to purchase local is nice when you need it now in larger volume than what the local hobby lobby has they don't stock the one two three gallon sizes . But that discount and that product are a fine product to learn with. Good luck and ask lots of questions there are many people willing to help out. And lots of forums / you tube / alumalite/ smooth on vidios. To watch and learn.

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I have some Micro Mark CR-300 urethane resin I've been using for over a year.  Recent castings have tiny (less than 1 mm) bubbles just below the surface of the bottom of the piece, i.e., next to the detailed part of the slush mold.  I've squeezed the resin bottles to get as much air out as possible.  Is there any cure?  Sanding causes the bubbles to expand and once their surface is open I have not been able to fill or seal them.  BTW, I greatly prefer CR-300 to any alternative I've tried:  little smell, easy to work (a little softer than model car styrene).

Uncured urethane resin absorbs moisture from the ambient air. That will cause bubbles when cured (through a chemical reaction).  If you had your resin for a year then it most likely absorbed moisture with the expected result.  You need to buy a fresh batch. You can use a gas-blanket spray to prolong the shelf life (Micro-Mark should sell that too), but even using that the resin will eventually be unusable (it unfortunately has a short shelf life).  Also, if there is any moisture in the molds, that will also cause bubbles to form in the resin.

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  • 1 month later...

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