Help selecting a Post Driver

[Barnbuilder]

How straight can they get a line using a driver. The ones I've looked at and liked were $15-20k. They had tilt offset and and an auger. I've been putting up fence off and on for 33 years. Like you said using a tamp all day hasn't done a lot for my joints. And using a driver would mean no 80lb bags of sackrete/hole which I could drop my price $1/ft just in material.

 

[Barnbuilder]

How straight can they get a line using a driver. The ones I've looked at and liked were $15-20k. They had tilt offset and and an auger. I've been putting up fence off and on for 33 years. Like you said using a tamp all day hasn't done a lot for my joints. And using a driver would mean no 80lb bags of sackrete/hole which I could drop my price $1/ft just in material.

 

[byrd]

Using a power beyond port as a return on a Shaver valve set as an open center valve is needlessly redundant. The valve is open center, return flow when the valve spool is centered is open via the zero pressure return connection. The only time the flow is deadheaded would be if you held a spool in lift position with the cylinder fully extended.

Just to be clear... because I am a hydraulics idiot... since the control valve is open center, if the valve is left in the center/neutral position, flow will continue through the valve straight to the return/drain line back into the transmission?

Since the nature of a post driver is to fully extend the cylinder for a very short period over and over and over, could the constant short period of deadheading accumulate to result in any sort of damage to the system over a prolonged period of usage. As a minimum is sounds like the recommendation would be to never hold the cylinder in the fully extended period since there is noting to act as a bypass valve?

I'm still curious... is a special adapter needed to converter an output port on the valve to a power beyond port? Would that then act as a bypass valve if the cylinder is held in the fully extended position (either plumbed using the two sides of a rear remote or plumbed by a formal power beyond port on an FEL valve)?

Thanks so much everyone for all the great information!!! This thread has been a great source of info for much more than just the post driver itself. :thumbsup:

 

[JimRB]

The Shaver I used had a supply line under pressure and a big return line that was plumbed directly into the fill port of the transmission. I got a nipple from the hardware store that I adapted to the return line from that hydraulic ram of the driver. That was something like a 1" return line. I used a dump port (not the lift port) of the 4 lines for the front end loader. I pulled the loader control using a bungie cord which supplied me with plenty of fluid back at the driver. You pull the driver one direction to lift it. Push the other to let it slam down. Up and down. I recall 3 minutes a post to pound a 4/4 post pointed with a chainsaw. Moist red clay of Georgia.

The driver I used had a control valve which was a dead end if I recall correctly. Then again it has been 19 years since I did my over 500 fence posts set 8' on center. The posts are pretty straight even after 19 years. Pretty plumb too. Well good enough. Too dark to take a picture.

You have read the owners manual? http://www.shavermfg.com/media/uploads/HD8-Operator-Manual.pdf The controls are not the same as the now 30 year old driver I was using.

 

[RickB]

Just to be clear... because I am a hydraulics idiot... since the control valve is open center, if the valve is left in the center/neutral position, flow will continue through the valve straight to the return/drain line back into the transmission?

Since the nature of a post driver is to fully extend the cylinder for a very short period over and over and over, could the constant short period of deadheading accumulate to result in any sort of damage to the system over a prolonged period of usage. As a minimum is sounds like the recommendation would be to never hold the cylinder in the fully extended period since there is noting to act as a bypass valve?

I'm still curious... is a special adapter needed to converter an output port on the valve to a power beyond port? Would that then act as a bypass valve if the cylinder is held in the fully extended position (either plumbed using the two sides of a rear remote or plumbed by a formal power beyond port on an FEL valve)?

Thanks so much everyone for all the great information!!! This thread has been a great source of info for much more than just the post driver itself. :thumbsup:

Yes.
No.
Yes.
No.
No.

 

[ishiboo]

Yeah, you're fine if the valve is open center.

 

[byrd]

Yes.
No.
Yes.
No.
No.

LOL! Thanks for the answers! :laughing:

Actually shouldn't the main relief valve (in my tractor I think it's in the main FEL valve block) come before all the cylinders in the system (even before the rear remote which I'll used to supply the driver), so that the relief valve would still actuate even if the post driver was held in the fully extended position for a period of time? This would be similar to over extending the FEL in any of its four positions when you can hear the whine as the relief valve opens. I think in the L4400, the FEL valve block is first in the system, then anything on the power beyond, and finally the 3pt hydraulics and rear remotes.



...I did find the video below to be very helpful in getting a better general understanding of the system. It just took a little bit of time to learn all the hydraulic circuit symbology.

How to Use the Power Beyond Facility in a Hydraulic Directional Control Valve (with improved audio) - YouTube

This is all starting to wander a bit off of the original topic, but I think it's all related information if anyone comes searching in the future.

 

[SPYDERLK]

Just to be clear... because I am a hydraulics idiot... since the control valve is open center, if the valve is left in the center/neutral position, flow will continue through the valve straight to the return/drain line back into the transmission? [1]

Since the nature of a post driver is to fully extend the cylinder for a very short period over and over and over, could the constant short period of deadheading accumulate to result in any sort of damage to the system over a prolonged period of usage.[2] As a minimum is sounds like the recommendation would be to never hold the cylinder in the fully extended period since there is noting to act as a bypass valve?[3]

I'm still curious... is a special adapter needed to converter an output port on the valve to a power beyond port?[4] Would that then act as a bypass valve if the cylinder is held in the fully extended position (either plumbed using the two sides of a rear remote or plumbed by a formal power beyond port on an FEL valve)?[5]

Thanks so much everyone for all the great information!!! This thread has been a great source of info for much more than just the post driver itself. :thumbsup:

Yes.
No.
Yes. why?
No.
No.

The valve is holding the lift pressure when the lever is centered; not the pump. ... Bypass - if the lever is held operated for some reason - goes through the tractor pressure relief.

 

[RickB]

The valve is holding the lift pressure when the lever is centered; not the pump. ... Bypass - if the lever is held operated for some reason - goes through the tractor pressure relief.

True. My answer was specific to the Shaver valve alone; with or without the PB circuit as discussed. The tractor system relief is the protection.

 

[byrd]

The valve is holding the lift pressure when the lever is centered; not the pump. ... Bypass - if the lever is held operated for some reason - goes through the tractor pressure relief.

True. My answer was specific to the Shaver valve alone; with or without the PB circuit as discussed. The tractor system relief is the protection.

Thanks for the help. I think this covers my last question, and I think I'm now in pretty good shape. I'm just gonna keep my eyes on Craigslist for a little while to see if I can find a deal. If I run out of patience, then I'll pull the trigger on the new post driver. It might be a bit dry now anyway. I'm thinking that, in my area of VA, fall will probably be a good time to put in some posts.