Mini excavator post driving attachment

I have put many (>1200) posts in and most were put in with a post pounder. My experience is that for truly hard ground, you need a weight of more than double of what you have on your device. Mine was a little over 1000 pounds (> 450 kg) and I would be able to drive through the hardpan.

Sometimes you will find a rock well below the surface and you know its a big rock because there is a really large shock pattern versus when the post is driven into dirt.

When driving 6" posts, the big weight was best. The hardpan here was such that I might make less than a 1/2" per hit.

When driving 3" posts, I dropped the weight to about 400 pounds. My weights were plates stacked, so changing the weight was removing a bolt on the top of the stack, removing the lift cable out of the way, and then removing or adding plates. I also built a custom post interface plate for the smaller posts. It had pieces of pipe welded onto the interface plate to cup the top of the post.

Probably your biggest issue will be the stability of the excavator holding the weight up that high and the shock that will be transmitted to the excavator arm... Most pounders have the active machine attached as low as possible, easier on the machine and better for stability (and safety).

Mini excavator post driving attachment - video