Using White Gel Coat 

Tips for Using White Brushiing Gel Coat

White brushing gel coat is a basic for hand laminating fabricating, and will remain tacky between coats allowing recoating if required.  Use for repair work and interior coating.  Isophthalic grade is the upper grade of resins which means the product in waterproof and is suitable to use below the water line. It has limited chemical resistance but is suitable for mild acids.  For best practice, itís best to test the chemical for any adverse effects.  Other applications include water tanks, potable water tanks, waste tanks, grey water tanks. Brushing get sands very well and blends in with existing gel coat surfaces. 


If youíre tinting this product it only contains white with no other color added, so itís considered pure white.  Remember you can't make a solid color from white as it will always be a pastel shade.


Use Rayplex Pigments only.  They are made specifically for gel coats and should be used when tinting or coloring polyester gel coat. Any chemical foreign to the polyester can interrupt the curing process and damage properties.  No more than 1 ounce of color agent should be added to a quart of white gel coat.


For part fabrication this white brushing gel coat can be brushed onto a mould with good coverage usually with one coat.  The gel coat covers well, but sharp corners may require and extra coat for proper coverage.


For interior coverage add 5% of wax solution.   Wax solution floats to the surface and prevents oxidation which gives gel that sticky feel when cured.  This will give a tack free  non sticky surface.  If more gel coat must be applied, the surface will have to be well sanded and the wax coating removed with solvents.


1)  Don't over catalyze as this will prevent the gel coat form curing properly. Gel coat is still tacky (a finger leaves a fingerprint) after hardener has been mixed into the resin and proper cure time has elapsed.  Never exceed 3% catalyst by volume or below 1.2%.  We reconmend not using this product below 60F.   See the Catalyst mixing guide in the How To section of  Always mix in clean containers, used coffee cups can impart a yellow cast to gel coat. 

2)  It is recommended that gel time be checked in the customer's plant because age, temperature, humidity and catalyst will produce varied gel times.

 3)  Never thin with or add  acetone as this will inhibit the gel coat from curing properly and will be soft.  Use streyne to thin with.


Prior to full cure, gel coat can be removed with acetone. Be sure to put all tools into an acetone bath before the gel coat has time to harden.



 Information present herein has been compiled from sources considered to be dependable and is accurate and reliable to the best of our knowledge and belief but is not guaranteed to be so. Nothing herein is to be construed as recommending any practice or any product violation of any patent or in violation of any law or regulation. It is the userís responsibility to determine for himself the suitability of any material for a specific purpose and to adopt such safety precautions as may be necessary. We make no warranty as to the results to be obtained in using any material and, since conditions of use are not under our control, we must necessarily disclaim all liability with respect to the use of any material supplied by us. Rayplex Ltd


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