Hi, have a new project on my car and making an glassfibre frontspoiler with carbon skinning on top. Big issues with the resin cure.
I have now put 5 layers of resin and everytime i want to sand the surface flat the resin clogs up the sandpaper. the resin is still litlebit sticky after 24h. I have also tried to let the resin cure 48h but when sanding allways the resin is clogs up the sandpaper. 
When sanding the sticky part of its fully cured under it. what is the problem here? 

Hi Chris,

When you say you building layers of resin how much time you giving in between coats ?

please let me know how you doing process see if I can help with it .

Thanks 

2-3h between coats of resin.(no sanding between coats/layers) But no bigger differense if i wait 24h or 48h until the sanding process. The very top of the resin is litlebit tacky and pain in the a** to sand. If i press hard on the part it will be fingerprints int the resin.

This means your resin is not cured properly you will have to leave it for even longer .

I normally wait for 1hr or more depends on room temperature in between layers and I would say do 3 layers wait over night giving that part is properly cured in 25c temperature, make sure resin is tacky before lay another layer , i do 3 layers leave over night post cure in oven 50c for 4 hours then sand it down clean and build more layers if necessary.

What temperature are you working in?

Worktemp around +- 20c. Going to give it more time 👍🏻 Next step to try. Thank you