Quote Originally Posted by JAZZCNC View Post
Do it after the pour it drills easy and doesn't cause any problems.

One word of warning with the epoxy and this cold weather.? I've just done a pour using 206 hardener which is faster curing and in a thermasticly heated workshop and after being left 5 days I still got a little sinkage after fastening rails. Nothing major but still enough to need a slight shim to avoid putting bind on the bearings.
Using the 209 I wouldn't touch yours for at least 10days. If you have any spare epoxy pour a little into something to simulate the width and depth your doing and then wait until it's gone hard so snaps when trying to bend. If it bends and doesn't break it's not ready. The surface will feel hard to touch but it won't be cured all way thru.
I cut my bridge off when the epoxy had been on for 10 days and used that (it was on parcel tape on the bridge so just slipped off no porblems) to do a snap test...made sure this time as I had proper bendy epoxy last time....