Just as a heads up... The silicone in syringes won't prevent set up. It will cause the dreaded "fisheye" problem (an area that won't retain any finish, resulting in a "fisheye"). If you don't get the rod to set up in the first 6 hours, the best thing you can do is get it warm. The 2 part epoxy needs to catalyze and heat is the critical element that allows it to do so. With the weather as cold as it was, it took one of my rods 12 hours to get tack free, and another 4 for it to get "hardened".
In general the only real causes of not setting up properly.
1) Messed up ratio of hardener to resin
2) Improper stirring
If those 2 things are correct, you should never have an issue with setup.