We use concrete anchors of different breeds quite a lot. One thing I've noticed is Tapcons do better with a hole drilled with a hammer drill instead of a rotary hammer. You said you're using SDS bits? Normally a rotary hammer bit. Try the Bosch hammerdrill bits and see if it helps
+1000000000 on that. I use them everyday and Knipex is the best. It is smoothe and easy on tired old arthritic hands. I am fixing to be 67 and usually work 6 days a week. If I tell you a tool is good to go, you can take it to the bank.
Fnsane
Guys, you use the 60 degree table below 1/0. above 1/0 use the 75 degree table. You only use the 90 degree table to derate.
Kevin, you are in SC. Correct?? I just happen to be a licensed General Contractor and Electrical Contractor in SC and several other states. I realize these forums...
I had 2 makitas on a service truck, my help tried their best, defaced them but could not break them. got new parts from website, rebuilt them, look like ****, run sweet. They are good stuff.