Adding down-pressure to a post hole digger (PHD)

ayelvington · Apr 26, 2016

My soils, along with the grass, make it difficult to drill post holes.

Necessity is the mother of invention, and I'm cheap. With a neighbour's help I was able to gin up a solution to get the auger on it's way to the earth's core.

Started with a piece of 3/8" plate and drilled a hole to accept a CAT-l lift pin. Another neighbour machined the pin to give 3/8" on the thread end, and 1/8" of shoulder to weld with on the pin end.

I tapered the back hole and the pin end so that the weld had good penetration on the back side. Then I ground it down flush. Flipped it over and and welded the shoulder to the plate.

Took the paint off of the PHD at the weld points and stuck the mounting plate in place.

The plate can hold two 50lb bar weights using a CAT-1 to CAT-2 adapter sleeve. Now I've got some drilling action!

Sawyer Rob · Apr 26, 2016

The way I "fixed" my poor performing cheapo POS post hole digger, was to send it "down the road" AND buy one from Bush Hog... It's one of the smarter decisions I ever made!

The Bush Hog is night and day better!

SR

5030 · Apr 26, 2016

Not bad.

RSKY · Apr 27, 2016

When I was a young boy. That is 13-15 years old. We spent three summers fencing our home farm. Dad would operate the tractor. My job was to keep the post hole digger straight and ride it down using my weight to provide downforce.

They would lock parents up for having a kid do that now.

It would get really exiting, really fast, when the digger would hit a yellow jacket's nest.

Long, hot, exhausting days.

RSKY

rd_macgregor · Apr 27, 2016

I assessed the pros and cons when I was looking for an auger and decided on a front-mounted hydraulic one. I have both down force and reverse capabilities with the hydraulic unit. I could even drill angled holes if I wanted to.
Since you already had the standard PHD, your approach is a more affordable improvement than buying a whole new replacement system.

stuckmotor · Apr 27, 2016

I haven't needed down pressure on my POD. The screw at the end seems either soften the ground or pull the auger in nicely. However! I think I'll save the plates when I scrap that old weight machine.

prs · Apr 27, 2016

Same thing as said by RSKY, Dad and I would take turns riding the auger frame.
No pto shield on tractor, no shield on pto drive shaft, and nary a care either.

I was also about 14 Y-O. Our tough clay shale ground would fight even a new
bit and soon the new bit was well dulled. He had a good friend with a shop that
specialized in mining equipment repair. They made a set of set cutters and a
point for the same auger. WHOA! No more riding the auger frame! It would
stand the tractor up in a wheelie if you did not let it down real slow and it would
dig rock.

prs

RPW · Apr 27, 2016

On mine the problem with the augar was not enough bite. I changed out the center point ot a better more aggressive one and added some teeth and re-enforement plates to the cutting edge of the augar. Now I have to be on top of the digging so it doesn't pull down "to" fast. Only problem I've encountered is that when I hit rock instead of skipping it will snag and bend the cutting edge back. I need to re-enforce it more.

buickanddeere · Apr 27, 2016

Don't need down pressure if the proper auger bit is used. would not know that I had the same machine after updating the chisel tooth bit.
The first factory type auger may have been ok in beach sand or wet soil. no good in firm soil or on sod. 2nd link is a superb piece of engineering.

9" AUGER BIT

Cast Auger 1" x 48" w/ 2" Round | Danuser

orezok · Apr 27, 2016

I can tell that many haven't tried drilling in the deserts caliche "soil". There are places that even adding 230# of weight on the PHD and using carbide cutters that the thing will just sit there and spin. Only answer at that point is the jackhammer which I have to use often.

I'm not even sure if a down pressure kit would work.

stuckmotor · Apr 27, 2016

orezok said:
I can tell that many haven't tried drilling in the deserts caliche "soil". There are places that even adding 230# of weight on the PHD and using carbide cutters that the thing will just sit there and spin. Only answer at that point is the jackhammer which I have to use often.
I'm not even sure if a down pressure kit would work.

Orezok,
I traveled through the south west over 25 years ago. It was hot and dry, there were fences beside the road, and maybe 4 cows to the mile. I haven't been able to figure out, to this day, how anyone can make money with so few head to the acre. I can't even see how people even recover the cost of the barbed wire and fence posts. Now you tell me that you have to have a jackhammer to dig post holes! I wish I could understand it.

orezok · Apr 27, 2016

stuckmotor said:
Orezok,
I traveled through the south west over 25 years ago. It was hot and dry, there were fences beside the road, and maybe 4 cows to the mile. I haven't been able to figure out, to this day, how anyone can make money with so few head to the acre. I can't even see how people even recover the cost of the barbed wire and fence posts. Now you tell me that you have to have a jackhammer to dig post holes! I wish I could understand it.

Well apparently those were CASH COWS!

PHPaul · Apr 28, 2016

I added this cylinder to my PHD. It effectively acts as "down pressure" by transferring force from the PHD boom to the lower links of the 3ph.

It will lift the rear tires of the tractor off the ground.

Works brilliantly, but does complicate things just a bit as you have to retract the cylinder while lifting the PHD out of the ground.

Also, had to re-engineer it a bit since that picture to weld the lower anchor point to the hoop. You can see the tab is already bending in the picture.

stuckmotor · Apr 28, 2016

orezok said:
Well apparently those were CASH COWS!

I'd like to borrow one of those cash bulls and introduce him to the girls in my pasture.

Fallon · Apr 28, 2016

Normal down pressure setups are single acting cylinders & have a pressure relief valve going to the tank (not a QD). As you lift the 3pt, the pressure relief kicks in & dumps fluid to the tank. Won't work with a QD on a double acting valve as its closed by default.

May want to find such a pressure relief valve & plumb it into the cylinder end & the tank. Just put a vent on the rod end to turn it into a single acting cylinder. Would make operating it a bit easier, not to mention safer.

Balancing on a PHD auger & your front axle pivot isn't a great idea... I can do it with mine. I have a quick hitch & hydraulic top link. I cut the PHD frame to fit the quick hitch. The top link + 3pt give enough range to dig to full depth. Without the top link it wouldn't work as with the QH you loose the leverage a normal PHD has to get the 3-4' of movement out of the 1' of 3pt movement.

ayelvington · May 3, 2016

It's a Woods PHD, so no complaints about the PHD by itself. Here are better photos and a video:

Just a few more views of the weight holder that I...

PHD enhancement with free weights for down pressure - YouTube

EddieWalker · May 4, 2016

Hope the added weight works out for you. I tried adding weight to mine, and then I added a 2x6x12 to the side of it, sticking out real far so I could hang from it while my wife worked the tractor. Then I read about other augers with replaceable cutting tips and looked into them. My first choice was a Speeco brand auger that worked pretty good, but it's cutting tips wore out quickly. One weekend when I was trying to finish off my fence and couldn't find any more cutting tips for it, I went to Tractor Supply and bought their Country Line brand auger. They had plenty of extra cutting tips in stock. I couldn't believe the difference. That auger drills through hard packed red clay like it's sand. For the first time every, I learned what others where talking about when you bury your auger. It digs down so fast that you can't pull it up. It will compress the rear tires on my tractor as it locks itself into the ground. With this auger, my biggest challenge is to keep pulling it out of the hole so it doesn't bury itself. Finding the right tool sure has changed everything I thought I knew about drilling holes in the ground!!!!

5030 · May 5, 2016

What you need to do is build a platform on the backside so one of your 'friends' can stand on it while you drill. The fatter the friend, the more downpressure applied.