Hi,

I have recently mixed Pattern-Coat primer (196g to 4g of catalyst) and applied to a mold for a kit car fender.   The material remained very tacky after 24 hrs, so I need to remove it and start a fresh.   Unfortunately, sanding is proving difficult as it clogs the sandpaper and is just being smeared around the plug, almost as if the catalyst had not been added or stirred in (both of which I was very careful with).

Can you suggest an easier way of removing the product (would white spirit work given its consistency?), and advise what I might have done wrong?.  I left the product in a trailer to cure at around 15 degrees, but moved it to the house to try and cure at 22 degrees, mush to the wife's discontent. 

Feedback greatly appreciated.


Regards



Steve

Your catalyst ratio was about 2% which should work fine.  It is a bit strange it has not gone off. Even at cool temperatures, I would expect the move to a warmer climate for a day or so would have solved it.  Unless there has been a lot of moisture absorption over night in the trailer? 

If it is still semi-solid, I would go for a  scraper to remove it as sandpaper will just clog too quickly.

Once the majority is removed, i would wipe it down with acetone to break down any remaining material.
Before you go again, do a small test batch to rule out problems with the resin or MEKP. It should cure hard and be sandable.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant