[flyingfrizzle]

I have also used a Low Viscosity Hydropel VE infusion resin from AOC when I played around with it. Bought a full 55 gallon drum left over from a hard top going on an Hatteras. Having a low viscosity resin is a must. Most infusion resins are low growth which helps also. Far as your question, I found out it was better to do the gel coat and let it harden first or you can get print threw from the cloth. AOC list a specialty product that claims it can be used on wet gel with low print threw in their brochure though. I found that by time you spray or roll the gel coat and prep for the infusion the gel will be cured enough to continue. It cures enough in 30mins to an hour to be ok to lay up over. It is kinda hard to find VE based gel coat but its out there. I ended up doing it over poly gel and it worked ok. Most of the stuff I done I didn't use gel at all as the AOC resin I had was designed to cure out white for easy paint coverage (long as you use clear mekp). I just waxed the molds and did it all in one shot since the resin cured almost as white as gel plus I was painting the parts anyhow.
On the core to use, It depends on the use of the part. I have had core cell with holes drilled on 1" squares to let resin and air pockets pass. The core material I have currently has scores on both sides in opposite directions mainly for forming curves but it aids in letting the resin flow as well.
I found the infusion consumables to be expensive but found some more affordable options such as using spiral plastic wire protector for flowing the resin and plastic foils from my ol lady's work for bagging. I also found that the metal roofing seam tape works well for sealing the bag and appears to be what they send you anyhow just at twice the cost or more. I found out the hard way a few times how not to do it but here are some helpful tips that aided in helping me:


I used a large shallow pan to draw the resin out of to slow the cure time.
Done the infusion while it was rather cool in my shop then closed the doors and kicked up the heat to cure.
Had extra resin on stand by that I could kick and then to add to the pan if I was running low.
Try to not mix hard to introduce air bubbles in the resin and let it sit to gas out the bubbles.
Make sure I had plenty of routes for the resin to evenly cover the entire part.
Have a pump that will pull plenty of vacuum.
Make sure the bag will actually seal up well.


You can learn a lot more from others as I have only figured out a few things the hard way and have a long way to go to be good at this. I found it much more easy to hand lay the cloth and resin then bag it and draw vacuum but then you are not infusing the resin then.


I will attach a link to the resin I used...