Went to California to help my brother-n-law build a hydraulic post driver. We incorporated the back of the fork lift attachment I built for him.
http://www.tractorbynet.com/forums/welding/347241-fork-attachment-build.html?highlight= The weight is just under 300-pounds.
He has 20-acres of shale rock. So we took an old truck axle he had, and ground a point on it. When he hits some shale, he will just drive the axle in the hole to break up the shale rock. Then drive the T-post.
I didn't get a lot of detail pictures
. We built a follower that slides under the striker plate for T-posts, and for wood posts. It works great!:cool2: