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Speeding Up Demold Time With KICK-IT™ Accelerator

KICK-IT™ Cure Accelerator is an additive designed to “accelerate” the cure time of some Smooth-On urethane liquid rubber products without significantly affecting the ultimate physical properties. This allows for much faster removal (demold) of a part or rubber mold from the original model.  The accelerator is added to Part B by weight and should be thoroughly mixed with Part B before adding Part A.  Important:  Adding the accelerator drastically reduces the pot life (time you have to mix and pour material) of the liquid rubber product.

Example:  To reduce the demold time of PMC-724 from 16 hours to 2 hours, add 10 grams of KICK-IT™ to 1000 grams of PMC-724 Part B.  Mix thoroughly for one minute, making sure that you scrape the sides and bottom of your container several times.

Next, add 100 grams of Part A and mix thoroughly for one minute, again making sure that you scrape the bottom and sides of your container several times.  Do not delay between mixing and pouring, as your pot life is about 5 minutes.  In two hours, the rubber mold can be removed from the original model.

Polishing Crystal Clear™ Plastics

We are often asked how to attain (or restore) a smooth, gloss finish to the surface of a casting made from a Crystal Clear urethane plastic and offer the following buffing technique using progressively finer grit sand papers and sanding gels to improve surface finish.

Every casting surface is different. For surfaces that have severe imperfections, you may need to sand with coarse grit sandpaper prior to moving onto the finer grit grades. If this is the case, we suggest starting with 120 grit followed by 220 grit and then proceed to using finer grit grades (see Step 1 below).

1.  Begin by sanding the abraded surface that you wish to restore with fine grit sandpaper (320 grit) until any prominent protrusions or grooves are removed.
 

2.  Next, sand with finer grit sandpaper (400 grit).
 

3.  Follow with ultra-fine grit sandpaper (600 grit).

Note: Water may be used with ultra-fine grit sandpaper to reduce particle clogging on the sandpaper and minimize heat buildup.
 

4.  Next, sand with super ultra-fine grit sandpaper with water (800 grit). After this step, there should be no visible scratches and the surface should appear smooth and translucent.
 

5.  This step is optional. If there are still some scratches or fine imperfections present, you can polish with Novus™ # 3 Heavy Scratch Remover and rinse under water. Dry off casting to inspect surface.
 

6.  Finish with a final polish using Novus™ # 2 Fine Scratch Remover, and rinse under water. Dry off casting to inspect surface. Repeat final polish until surface is perfectly clear.

For Novus™ Plastic Polish products, visit www.novuspolish.com

Important; Results may vary due to a number of variables such as configuration of the casting, quality of the original casting, etc.  As a result, Smooth-On can not guaranty or warrant that the above procedure will work for everyone. A small test on a non-critical area of the casting or different casting will be an indicator of whether or not this procedure will work for you.

Softening PMC-121/50 & PMC-744 Using SO-FLEX™

SO-FLEX™ is a softening agent that lowers the cured durometer of a variety of Smooth-On polyurethane products. The charts below indicate the effect SO-FLEX™ has on full cured (7 days) PMC-121/50 and PMC-744 when added as a percentage of the total mix.

Using SO-FLEX™ By Weight . . . For best results, you should use an accurate scale to properly use SO-FLEX™ with PMC-121/50 or PMC-744. SO-FLEX™should be weighed and must be thoroughly mixed (at least 
one minute) with the appropriate amount of Part B before combining with Part A.

Softening PMC-121/50 with SO-FLEX™

Normally, PMC-121/50 Cures to a hardness of Shore A 50.  PMC-121/50 can be made softer and more flexible by adding different percentages of SO-FLEX

Softening PMC-744 with SO-FLEX™

Normally, PMC-744 cures to a hardness of Shore A 44.  PMC-744 can 
be made softer and more flexible by adding different percentages of SO-FLEX™ as indicated below.