Shaver Post Pounder

[ChrisB2]

I've had an old Shaver HD-8 post driver that I've never been real impressed with. Been reading that the return line should go directly into the hydraulic reservoir and not through a remote on the tractor which makes sense. But the cylinder on my driver is a one way cylinder with only 1 hydraulic line, there is not even a second port to add a return line. The hammer seems to drop fast, but I'm wondering if it is not dropping as fast and hard as it could be? Would a different cylinder with an unrestricted return line be fast that my current setup?

I've had this driver for many years and it was well used when I got it, so I don't know if the cylinder has been replaced at one time. The springs have been replaced a couple times so they are good.

 

[chevytaHOE5674]

Doesn't it have its own hydraulic control valve in it?

 

[RDFF]

It still should have a larger return line on it (like 1" diameter), that goes straight to the oil sump. It needs to be larger so that the oil can more easily "free flow" without pressure. If returning back through a remote, I would guess that it WOULD restrict the drop, because "pressure from the hammer" would have to force the oil through a fairly small port. If you look at your couplers, they aren't actually 1/2" of space that the oil flows through inside (they restrict the oil further than your hose size)... even though you might be using a 1/2" hose, and the "fittings" are called 1/2". At 2500 PSI, you can push quite a bit of oil through a pretty small hole...... but when the hammer drops, you don't want that return oil to be restricted so that it's working against the hit you're trying to apply to the post with the hammer.

I've got the same unit. I did add some extra weight to the sides of the I beam to achieve a harder hit... but be careful here... the inside of that cylinder isn't made the same way that a typical cylinder is... (it doesn't have to dump ALL of the oil on the underside of the piston... which means it can cycle faster) but that also makes it so that if you add too much weight to the driver, you can easily get to where it won't be able to lift the I beam (larger models use a larger diameter cylinder... which of course would add some to the cycle time, without also having a larger hydraulic flow). Larger models also have larger diameter springs, to "assist" with the speed of the I beam drop.

All of the "weight drop" type pounders operate in the same way basically, even the "cable pull" ones. Kinda "dangerous", if you're not being careful...

 

[ChrisB2]

Doesn't it have its own hydraulic control valve in it?

No it doesn't, I run it from the remote lever on the tractor. Not a good set-up, takes 2 people.

 

[ChrisB2]

It still should have a larger return line on it (like 1" diameter), that goes straight to the oil sump. It needs to be larger so that the oil can more easily "free flow" without pressure. If returning back through a remote, I would guess that it WOULD restrict the drop, because "pressure from the hammer" would have to force the oil through a fairly small port. If you look at your couplers, they aren't actually 1/2" of space that the oil flows through inside (they restrict the oil further than your hose size)... even though you might be using a 1/2" hose, and the "fittings" are called 1/2". At 2500 PSI, you can push quite a bit of oil through a pretty small hole...... but when the hammer drops, you don't want that return oil to be restricted so that it's working against the hit you're trying to apply to the post with the hammer.

I've got the same unit. I did add some extra weight to the sides of the I beam to achieve a harder hit... but be careful here... the inside of that cylinder isn't made the same way that a typical cylinder is... (it doesn't have to dump ALL of the oil on the underside of the piston... which means it can cycle faster) but that also makes it so that if you add too much weight to the driver, you can easily get to where it won't be able to lift the I beam (larger models use a larger diameter cylinder... which of course would add some to the cycle time, without also having a larger hydraulic flow). Larger models also have larger diameter springs, to "assist" with the speed of the I beam drop.

All of the "weight drop" type pounders operate in the same way basically, even the "cable pull" ones. Kinda "dangerous", if you're not being careful...

Thanks, I'll have to give it a better look. Could be hidden and hard to see. Otherwise I see a couple of other used ones in the area that are plumbed "correctly" and also have the separate control valve to run it from the ground.

 

[chevytaHOE5674]

If your feeding the lift cylinder directly from your tractor remotes then there's no way to have a return directly to tank.

 

[RDFF]

Thanks, I'll have to give it a better look. Could be hidden and hard to see. Otherwise I see a couple of other used ones in the area that are plumbed "correctly" and also have the separate control valve to run it from the ground.

Yeah, mine has a separate control valve right on the pounder. BTW, if you get your timing off when raising/dropping, and happen to pull that lever to raise the pounder before it actually has hit (or maybe even on the rebound hit off the top of the post) you'll "shock" your hydraulic system... I broke my valve spool on the tractor that way, TWICE! Now I make sure I don't try to lift until it's for sure settled decent on the post... only takes a fraction of a second more time to be careful about that... but it saves a whole lot of time and expense putting a new spool into your valve stack!!!

It would have come from the factory with a separate valve on the pounder itself, and if I was you, I'd buy a single acting valve for it... it simply can't be operating as good as it should the way you've got it set up right now. And when you do that, you want to have like a 1" return line on it, that dumps straight into your sump. I'm not sure if the valve that comes with the pounder has a larger output/return fitting or not... I can look at mine and see, and post here what I find... but I KNOW that my return line hose is for sure a 1" (doesn't HAVE TO BE high pressure hydraulic hose, just "oil resistant"), and the pressure line going to it is 1/2" hydraulic hose.

 

[worldsgreatestlover]

I've had an old Shaver HD-8 post driver that I've never been real impressed with. Been reading that the return line should go directly into the hydraulic reservoir and not through a remote on the tractor which makes sense. But the cylinder on my driver is a one way cylinder with only 1 hydraulic line, there is not even a second port to add a return line. The hammer seems to drop fast, but I'm wondering if it is not dropping as fast and hard as it could be? Would a different cylinder with an unrestricted return line be fast that my current setup?

I've had this driver for many years and it was well used when I got it, so I don't know if the cylinder has been replaced at one time. The springs have been replaced a couple times so they are good.

The large fitting on the valve block is your return that dumps into the hydraulic reservoir.

 

[worldsgreatestlover]

Yeah, mine has a separate control valve right on the pounder. BTW, if you get your timing off when raising/dropping, and happen to pull that lever to raise the pounder before it actually has hit (or maybe even on the rebound hit off the top of the post) you'll "shock" your hydraulic system... I broke my valve spool on the tractor that way, TWICE! Now I make sure I don't try to lift until it's for sure settled decent on the post... only takes a fraction of a second more time to be careful about that... but it saves a whole lot of time and expense putting a new spool into your valve stack!!!

It would have come from the factory with a separate valve on the pounder itself, and if I was you, I'd buy a single acting valve for it... it simply can't be operating as good as it should the way you've got it set up right now. And when you do that, you want to have like a 1" return line on it, that dumps straight into your sump. I'm not sure if the valve that comes with the pounder has a larger output/return fitting or not... I can look at mine and see, and post here what I find... but I KNOW that my return line hose is for sure a 1" (doesn't HAVE TO BE high pressure hydraulic hose, just "oil resistant"), and the pressure line going to it is 1/2" hydraulic hose.

Just curious. Are you running that driver on a closed system.? Shaver makes a plug to keep that from happening
Edit . Breaking the spool valve

 

[tater74]

No it doesn't, I run it from the remote lever on the tractor. Not a good set-up, takes 2 people.

My Shaver HD8 has its own valve.
I can run it by myself from the the ground while driving a post.

I bought mine well used and it has worked flawlessly.

 

[ChrisB2]

The large fitting on the valve block is your return that dumps into the hydraulic reservoir.

Is there only 1 hydraulic line going to the cylinder? I do not have the valve block, that may be the issue.

 

[ChrisB2]

So, it appears that not having the control valve is my issue. I have not called Shaver to get a price on a valve yet, but I'm guessing it will be about the same price as a different used pounder. But I read one reply on a different forum that you could use a log splitter valve instead of the one from Shaver. Is this correct?

 

[simme]

HD8 Manual

 

[RDFF]

Is there only 1 hydraulic line going to the cylinder? I do not have the valve block, that may be the issue.

Only one to the cylinder, yes, but two at the valve body, the high-pressure supply line coming in, and the larger non-pressure return line.

1. The line coming into the far (left) side of the valve body is the high-pressure line from the tractor.

2. The larger line on the near (right) side is the non-pressure return line. It's got a larger pipe thread port coming out of the valve, and the hose itself is larger. I have a 1/2" pipe with an elbow inserted in the other end of the return line... and can just drop that into the oil fill hole on the transmission, for the return oil (I DO secure that in place there though... that return line jumps around some with the surging of the oil through it).

3. The line coming out of the top of the valve body is the pressure line (1/2") going to the cylinder. There's not a detent in the "pressure" position in either direction, only in the center (closed/resting) position. Pull the lever back, it puts pressure to the cylinder, push it forward, and the I-beam drops. That center position also "holds/locks" the position of the I-beam at any position too... so as you develop your rhythm... lift/drop-lift/drop... if you push too soon, before the I-beam has hit the post and is resting, the full force of that beam dropping will be absorbed by the pressure line... and relay that back through your tractor valve body and system. It'll hit harder and faster than your relief valve can respond, shock-loading the whole system... and that's how I cracked the valve body on the tractor. It'll find the weakest link of course... Don't know if this happened just the once and that was all it took, or if it was multiple times eventually weakening the tractor valve body (I DO know that this happened a few times without actually breaking anything... at least not immediately... but it could be "over time" with repeated hits like that, that it eventually had to give... best thing is to make sure that you don't make that mistake in the first place! :rolleyes: )

I've got my pounder mounted on the loader bucket... I like that much better than on the back end for positioning.


I also added a stabilizer leg to my driver (mine is just a single leg... don't have to "adjust" it for slopes then... but I can't imagine driving posts without that... the thing would be popping all over the place!

Mine is an "old" model... doesn't have any of the "safety features" on it... no "debris guard", no "safety arm frame" (just use my hand to stabilize the post in the I-beam... you don't want to be anywhere with your hand though than on the outside face... when that I-beam comes down, if it catches your hand it won't be pleasant!). Because I've got it mounted on the loader on the tractor (it could be on the skid loader too I guess, but I've never used it on that), I have been able to drive posts as long as 12' when necessary (they were smaller steel pipe posts that drove easily... so I didn't necessarily NEED that stabilizer leg... needed a ladder though to reach the control valve on the driver! I more like it there for easy positioning, and for reaching into places where I otherwise probably wouldn't be able to.

If you look at the valve image above, you can see the heavy C channel that I welded onto the bottom end of the I-beam for added weight (one on both sides of it). That's 1/2" thick 3" x 8" C-channel, about 24" long (keep the weight on the bottom end for balance). My thought there was that I could fill that C-channel yet with metal filings or something like that, for still more weight. However, I'm about at the right weight for the limit on lift capacity of the cylinder... so if doing it again, I'd just add some thick plate to the bottom end like that... kind of like "suitcase weights"... maybe about an inch thick or so on each side of the bottom 2' of the I-beam. As much weight as is practical, without overdoing the lift capacity of the cylinder... too heavy, and it'll slow down the cycle speed or not be able to lift it at all... If your post gets a little wonky in the I-beam and rubs, that also can work against being able to raise the I-beam... so you have to strike a happy medium on that weight. That's why they use a larger cylinder on their larger drivers.

 

[RDFF]

So, it appears that not having the control valve is my issue. I have not called Shaver to get a price on a valve yet, but I'm guessing it will be about the same price as a different used pounder. But I read one reply on a different forum that you could use a log splitter valve instead of the one from Shaver. Is this correct?

Yeah, I don't think there's anything "special" about their valve that's specific to the pounder. It just needs to be able to "free fall" when you open the valve for the drop. And of course, they've incorporated some "safety factors" into the functioning of the valve they use now (that "safety lever" which you have to be pulling in order to operate the valve lever).

 

[ChrisB2]

Did you notice a big difference after adding the extra weight?

 

[chevytaHOE5674]

I've got an HD12 Shaver and I added 82lb of lead shot to the top of the hammer and completely removed the springs. Pounds just as good as before and no noisy springs to break/replace.

 

[RDFF]

Some... but I wouldn't say a BIG difference. Another trick that I figured out was if the ground is hard and dry, it can pretty much stop you in your tracks... pound for a long time. Take a 5-gallon bucket and drill a bunch of holes in the bottom. Set it where you want to drive your post, fill it with water, and give it some time. I would let it sink in while driving in the "previous" post in the line. Move up to that now "wet spot"... go set the bucket for your next post, then go back and drive the one you've wetted... goes in like butter.

 

[RDFF]

I've got an HD12 Shaver and I added 82lb of lead shot to the top of the hammer and completely removed the springs. Pounds just as good as before and no noisy springs to break/replace.

Yeah, that was kind of my thought process for the C-channel filling.... Still have the springs on mine... but your right about the noisy springs. I think the idea of them is to "assist" with the speed of the drop and to capture/reduce some of the "rebound" off the top of the post.

 

[RDFF]

For those who HAVE used a drop hammer for pounding posts, and who have also used a "hydraulic repeating hammer" type, tell us of your experience, and why you like what better? Seems most today would tend toward the hydraulic repeating hammer... I've never used one. Pros/Cons you see of each?