All hydraulic post driver

[BHD]

the cylinder I have had a very small port in it, and I welded a larger fitting on over the port area of the cylinder as not to restrict, the oil any more, and it seems to work very nicely, again I used the smallest cylinder I thought that would work,

(I do not remember for sure but I think the port was either 1/4", and I welded on a fitting so I could use a 3/4" hose), so the hose inside diameter was larger than the port, and ended up wing stacked valves, with #8 SAE ports, and the valve does not seem to have any real restriction in it, when pushed clear open,

 

[franklin2]

Is there an advantage to the hydraulic style post drivers? I see possibly more control by using the valve lever to control the speed of the cylinder. But other than that, all you are doing is raising a heavy weight up and letting gravity do the work.

The reason I ask, I watched a older design post driver work, it was driven with a small driveshaft off the pto. It had a small gearbox and a couple of chains if i remember correctly. All it had was a large solid rubber tire that turned slowly all the time from the pto system. It had a large piece of metal that ran up and down in a track made into another vertical piece. I don't remember all the details but basically you had a lever that applied the rubber wheel to the metal piece to lift it up and when it got to the top you pulled the wheel away from it and it was free to fall on top of the post. It was a well thought piece, very old, and still worked well.

P.S. I just thought of another advantage to the hydraulic system; You could put the driver in a custom position easier than the pto driven unit. I guess most of the front mounted drivers are probably hydraulic.