What kind/brand plastic cup for mixing?

[Penl8the]

Hi All,

I have been using 10 oz clear plastic (drinking) cup made by Dixie Cups for mixing accelerator to PR.

I was trying to mix with PearlEx in PR like Johnathan (Brookes803) in (http://www.penturners.org/forum/showthread.php?t=57502).

I had 4 Dixie cups with 4 different PearlEx. Each cup has 2 oz. of PR. I mixed 4 drops per oz = 8 drops in each cup.

I waited 10 minutes for the PR to thicken/gel a bit. That was when I discovered all the plastic cups were leaking. In fact I could only recover 3 oz. in total for a smaller mold (please attached).




Now questions:

• What kind/brand of plastic cup do you use for mixing?
• Is 4 drops per oz too much accelerator?

Additional info:

• I mix my PR in the garage.
• The temperature was ~45 deg F in the garage.
• After mixing I brought the PR in the workshop which was about 70 deg F.
• The "recycle" number at the bottom of the cups is 5
• Accelerator and PR (Clear Polyester Resin) are from Castin' Craft
• PearlEx is from Michael's

Thank you in advance.

 

[RAdams]

I HIGHLY HIGHLY HIGHLY suggest you find yourself a silicone muffin pan. The floppy, flimsy fancy new ones...

Each cup is 5 ounces of non stick, heat stable silicone! Cut them apart and you have 6 five ounce cups that will last and last and last. The dried PR peels right out of the cups and they also make great pendant blank molds. You can even mix one color and leave a tiny bit in teh bottom of the cup and let it set up, then add another color on top and do the same. Once it sets the second time, you will have a reversable pendant blank!

I still use 3 ounce dixie paper cups to pour my resin in the pen molds, but for the actual mixing process, the muffin cups are the best!

 

[Glass Scratcher]

Are you saying that the cups that leaked were marked with the recycling symbol with the 5 inside it denoting Polypropylene?

 

[byounghusband]

Does Alumilite work in these as well?

I HIGHLY HIGHLY HIGHLY suggest you find yourself a silicone muffin pan. The floppy, flimsy fancy new ones...

 

[seawolf]

I went to small glasses. If you are doing a consistant pour just scratch the side of the glass to measure the amount of resin. After pouring a wipe with a paper towel to get the resin out then a paper towel with acetone to clean the last of the residue.
If you need to pre-heat the resin the glasses hold the heat better.
Mark

 

[Penl8the]

I HIGHLY HIGHLY HIGHLY suggest you find yourself a silicone muffin pan. The floppy, flimsy fancy new ones...

Hi All,

First of all, thank you everyone for your suggestions.

Hi Ron,

I lucked out. I went shopping for a silicone muffin pan, but found some silicone muffin cups/liners on sale for a pack of six for $1.45. I bought four packs.

These liners can hold 3 oz. each. I will report back how they will work out.

Hi Mark,

Small glasses are good idea also. There are jam jars in the basement. I am sure they jars would be missed.

Later.

 

[RAdams]

Bob, I don't know if alumilite would work in them or not, but i would be very interested to find out... All i have ever poured with is silmar 41 from USComposites.

Branden, I have never seen the silicone liners. are they meant to be disposable? My muffin cups are 5 ounces each. I can make a dozen blanks at a time with a 30 ounce pour, and still have some "slobber" in the bottom to make a pendant blank or two! sweet stuff i tell ya!

 

[JohnU]

I use the cheap CLEAR Plastic cups from Kroger with no problems. If theyre colored stay away from them.

 

[Penl8the]

Branden, I have never seen the silicone liners. are they meant to be disposable? My muffin cups are 5 ounces each. I can make a dozen blanks at a time with a 30 ounce pour, and still have some "slobber" in the bottom to make a pendant blank or two! sweet stuff i tell ya!

Ron,

We also call them cupcake liner.

For the Canadian members, I bought them from Real Canadian Superstore.

Here is a picture of them.

 

[jttheclockman]

Ron,

We also call them cupcake liner.

For the Canadian members, I bought them from Real Canadian Superstore.

Here is a picture of them.

Oh those would have made some cool design in my prop.

 

[rherrell]

I use paper cups, the kind you find at the grocery store that are used in bathroom dispensers. I have 3 sizes, 3oz. 5oz. and 9oz.. They work really well and you can leave PR in them indefinitely and they won't leak.:wink:

 

[RAdams]

Be careful with the muffin liners!

I think the resin is going to try to make them collapse unless you put them in a "Muffin pan" first.

My muffin cups have a lip around the top that offers some rigidity.