I want to have a good stake driver built for building stake beds. I need to drive stakes below water level... most likely driving stakes about 4-feet in length in 6 - 10 feet of water.

The principal is obviously the same as a standard fence post driver, except it has to reach below water level.

Can anybody provide me a photograph of an existing such stake driver they'd be willing to share here, or via e-mail?

Or a good description of how to build one that even a very "un-handy" person such as myself might understand?

Thanks in advance!