I just finished assembling the frame for a gravel pad where I plan to put a shed. Because I put it into the side of a slope, I needed to use 5 layers of 4x4's to get the proper depth. Currently everything's held together with decking screws, but I have read that it is best to lock everything together with 1/2" rebar. So basically I have to drill an 18" hole through the 5 layers of 4x4 (pressure treated). Today I tried to place the rebar using a 7.5Amp 1/2" corded hammer drill (Genesis brand) with a 24" inch 1/2" bit and a 3/8" shaft, and I got down to about 12" and the bit got stuck and the motor on my drill started smoking.
I'll admit I had overpowered the drill once before and saw smoke with a previous DIY task, so the drill could have been damaged to begin with, but my real question is this: I don't want to buy a new drill, I can rent a 4.2AMP corded makita hammer drill from Home Depot for about $40 for a day, but that's way less amps than the one I was using. I'm afraid of it either not getting the job done or possibly getting damaged. Do you think that that will cut it? Or is there a better approach to this?