HCb
Member
Hey, all, I had seen a few different styles of drivers for putting posts (other than T posts, but I guess this could be used for that, too) in the ground. I saw one a local guy was using for doing fencing work that simply hydraulically hit the top of the post with very little steel involved and rapid action (small bore, large rod cylinder driven single-acting on retract) and several online including a falling-anvil that the company claimed weighed 800 pounds (and cost almost $4k). I decided to build one myself.
I've posted a YouTube video of it in use. I don't have any still photos of the unit but I'll post some if anyone is interested and asks. Basically, I got a piece of I-beam from the scrap yard that was 9 feet tall, built a homemade quick-tach setup with a pivot, and then hung a heavy anvil on it. The anvil is made from 9-5/8" pipe sitting on a plate of 1" thick, 10" x 16" steel. The pipe is filled with smaller and smaller diameter pipe (whatever I had or could get from the scrap yard) and then filled with sand and capped. I tried a few variations and two different cylinders. I tried single-acting and double-acting with both cylinders. I ended up with a DA setup on a 2" x 16" cylinder. I tore the cylinder apart and bored out the fluid port passage on the rod end because the port was a 3/8" NPTF but the fluid passageway was only 1/4". The fluid passageway on the other end was large enough, I thought, and I left it alone. I used double pulley blocks I constructed. I started with some Horrible Freight pulleys rated for 4,000 pounds. They might HOLD 4,000 pounds in a static situation but they didn't handle this weight for crap in a dynamic situation. I blew two pulleys at different times. I then punched out the pulley plates and wheels to take a Cat 0 pin which I bored on a lathe and mounted a grease zerk in. Then I cross-drilled the pins to allow the grease to get to the pulley wheels. With the pulley wheels greased and the hooks mounted on 1/2" grade 8 bolts, they held up fine. The wire rope is 1/4". With the line being quadrupled, I get a nominal 54" of travel from the anvil at 4 times the cylinder speed. I have successfully driven 2-7/8" steel pipe with approximately 0.250" wall 3 feet into the clay soil we have around north central Texas. In the video I drive a 10' post 3' in the same soil.
I took some time to search for similar projects on this site prior to posting this and I'm sure I didn't see every thread about such projects. I'd love to hear any ideas for making this better. I did see one thread where a responder had suggested using an air reservoir with 100 PSI for the drive direction of the cylinder...a great idea I wish I'd thought of.
As it sits, I got most of the steel from the scrap yard. Some I had around already (like the 10" x 1/4" flat bar I used for the quick-tach shoes). I have about $500 in this thing including $100 for custom hydraulic hoses I, ultimately, didn't need, and another $100 for the 1-1/2" bore cylinder I started with but, ultimately, was not what I needed.
I would love some feedback, particularly ideas for ways to make this better.
Thanks.
YouTube - PostDriver.wmv
--HC
I've posted a YouTube video of it in use. I don't have any still photos of the unit but I'll post some if anyone is interested and asks. Basically, I got a piece of I-beam from the scrap yard that was 9 feet tall, built a homemade quick-tach setup with a pivot, and then hung a heavy anvil on it. The anvil is made from 9-5/8" pipe sitting on a plate of 1" thick, 10" x 16" steel. The pipe is filled with smaller and smaller diameter pipe (whatever I had or could get from the scrap yard) and then filled with sand and capped. I tried a few variations and two different cylinders. I tried single-acting and double-acting with both cylinders. I ended up with a DA setup on a 2" x 16" cylinder. I tore the cylinder apart and bored out the fluid port passage on the rod end because the port was a 3/8" NPTF but the fluid passageway was only 1/4". The fluid passageway on the other end was large enough, I thought, and I left it alone. I used double pulley blocks I constructed. I started with some Horrible Freight pulleys rated for 4,000 pounds. They might HOLD 4,000 pounds in a static situation but they didn't handle this weight for crap in a dynamic situation. I blew two pulleys at different times. I then punched out the pulley plates and wheels to take a Cat 0 pin which I bored on a lathe and mounted a grease zerk in. Then I cross-drilled the pins to allow the grease to get to the pulley wheels. With the pulley wheels greased and the hooks mounted on 1/2" grade 8 bolts, they held up fine. The wire rope is 1/4". With the line being quadrupled, I get a nominal 54" of travel from the anvil at 4 times the cylinder speed. I have successfully driven 2-7/8" steel pipe with approximately 0.250" wall 3 feet into the clay soil we have around north central Texas. In the video I drive a 10' post 3' in the same soil.
I took some time to search for similar projects on this site prior to posting this and I'm sure I didn't see every thread about such projects. I'd love to hear any ideas for making this better. I did see one thread where a responder had suggested using an air reservoir with 100 PSI for the drive direction of the cylinder...a great idea I wish I'd thought of.
As it sits, I got most of the steel from the scrap yard. Some I had around already (like the 10" x 1/4" flat bar I used for the quick-tach shoes). I have about $500 in this thing including $100 for custom hydraulic hoses I, ultimately, didn't need, and another $100 for the 1-1/2" bore cylinder I started with but, ultimately, was not what I needed.
I would love some feedback, particularly ideas for ways to make this better.
Thanks.
YouTube - PostDriver.wmv
--HC