Hi all, I have done some carbon wet lay in the past with good success. Have decided to try the uni mould and have stumbled across a problem - the gel coat started curing during application and went lumpy before I realised and had brushed on an area. I didn't have time to smooth the rest out eithwr as it would have curdled too ! Is this done for or can I just apply second goat as normal once tacky ? In other words is this going to show through and effect the final mould ?

Hello James, 

Probably best to peel it off and get it right then by the sounds of it.  It cured within about ten minutes, using 2 % mekp measured on accurate digital scales, did it indoors though and it was quite warm in the house so maybe why bit still.. that was fast ! Though I used a fairly small diameter mixing cup could this be the cause ? The remaining gel coat in the cup got very very hot and started to melt the cup slightly too ! 

You can always sand off the high spots and see if there is even coverage.  If there is put another layer over the top and then glass as normal.

Just used compressed air to blow the gel off, takes 30 seconds. 

I managed to peel the gel coat off fairly easily, it came off the part and the glass with ease - mould is now prepped and ready for take two !

Good luck keep us posted.........

Hi James.

Ive just done my first mould with the uni system and although I didn't suffer your problem I was close and the last bit of resin that I didn't use was lumpy.

All I can say is don't use a tall narrow pot to mix, one with a similar hight to width is best.

Get it out of the pot and onto the plug asap and you will find its workable for much longer.




When you move onto the next steps be very organised, cut all your matt ready, mix small amounts of resin, I found 500gram to be the max I could work and again work quickly and get the resin onto the job.

If you don't cut your matt before starting you will have problems as once started you need to keep flowing.

Take two was successful, Ready for Glass fibre tonight !




Amazing how much effect the room temperature has on cure time !

Yep, every 5 degrees C above room temperature halves your pot life. Making moulds in our 40-45 degree C summers here is the bane of my existence.