I'm working on driving threaded inserts into hickory table legs to be used to secure the legs to the table. I bought the ez-lok 1/4-20 303 stainless inserts for hardwood and the associated driving tool. I drilled out the holes with a 3/8 forsner and then reamed them to the 25/64 (what the manufacturer recommends) with a twist drill. I started them in the drill press turning the chuck by hand as I pushed the quill down. They all started just fine in the holes. I then used my impact driver to try and drive them home. The first leg went in perfectly. The second leg I ended up breaking the slots on the threaded insert and had to carefully back it out so I could replace it. I then noticed that the driving tool was a pretty beat up, like the impact had done a number on it (are these tools meant to be run with an impact?). I'm now waiting on replacement parts to ship from rockler - 2 driving tools and some more inserts so hopefully I can get them all driven. Are there any tips to getting these things to drive home successfully? Its been years since I last used a threaded insert, and I had forgotten about putting wax on them before driving them, so I will definitely be doing that. I'm debating if I should upsize the holes to 13/32 since this hickory is tough stuff, or at least in the legs that are giving me trouble - they drove in smoothly into the first leg and were really fighting on the second leg before they broke. Anything else I should be doing?