Posthole Digger Speed to run post hole digger

[NTG]

Well, I tacked onto an older thread since my question was relevant to that thread and no one answered, so figured I'd start a new thread. It was only since yesterday afternoon, but you guys are usually pretty quick to answer, so I'm not sure how this forum handles the ordering of older threads. Anyway.....

I have a NH Workmaster 33 tractor and just bought a CountyLine PHD from TS. I've read places that you should operate the PHD at a slow speed to keep from screwing it in the ground, but my tractor manual says to operate the tractor at 2400 RPM with the PTO engaged. (Well, you start it out at idle and then increase it to that RPM) My PHD manual says to "start digging at a slow speed", but it doesn't mention any specific RPMs. Says to increase speed as the auger goes deeper and if the soil is extremely hard, it will generally improve operation to vary the speed of the auger at times. Do I just engage the PTO at the tractor's idle and go at it with the PHD? Will it damage the PTO if the auger is not running fast enough or will it just bog down? Do you just increase it a little bit at a time until it starts biting? Most of my soil is probably going to be straight red clay once I get past the first couple inches and I realize I may have to dig my auger out at some point, I just don't want to damage my tractor while trying to get the hang of this. My tractor is 32hp and I'm using a 9" auger.

 

[widefat]

I wish I had been smart enough to ask this before I used my PHD for the first time.
Manual? I dont need no stinkin manual.
I figured since PTO speed was 540, I should just run that sucker right up to 540. So I did.
When I dropped the auger, it grabbed earth and disappeared in about .2 seconds. The tractor whined, the front wheels got light, and
I developed a serious case of **** pucker.
That's ok though, at about 1.2 seconds into the event (it seemed like hours), the shear bolt snapped and everything settled down.

After that,I learned to start at very low RPM and adjust according to how fast the PHD auger dug in, and to back it out often to keep it from getting hung.

 

[Curly351]

I wish I had been smart enough to ask this before I used my PHD for the first time.
Manual? I dont need no stinkin manual.
I figured since PTO speed was 540, I should just run that sucker right up to 540. So I did.
When I dropped the auger, it grabbed earth and disappeared in about .2 seconds. The tractor whined, the front wheels got light, and
I developed a serious case of **** pucker.
That's ok though, at about 1.2 seconds into the event (it seemed like hours), the shear bolt snapped and everything settled down.

After that,I learned to start at very low RPM and adjust according to how fast the PHD auger dug in, and to back it out often to keep it from getting hung.

OMG still laughing, great writing, and a good tip, thanks

 

[George2615]

I always start my PHD at idle and then raise speed a little bit. I see no reason to run a PHD at 540 RPM. Most times I'm between 1000-1600 RPM.

 

[CobyRupert]

In my case, the rpm speed is just going to determine how fast and hard you're going to bounce it off the inevitable rocks I encounter. And how fast I can break the shear bolt. I don't get anywhere close to 540 rpms. Maybe 50% to 65% (max).

Like widefat alluded to, the most important thing is being able to frequently raise the auger back up, and letting the dirt clear, instead of it corkscrewing in too much and then you're screwed too.

So the rpm you run it at is one where it slow enough where it doesn't corkscrew in so fast it gets away from you, yet maybe fast enough that when you raise it up often that it throws the dirt off.

Now here's something else to think about: The lifting force of your 3 point hitch (to counter-act being corkscrewed), is also a function of engine rpms, so it's a bit of a catch-22.
So personally, I control the rpms with my foot throttle and vary the rpms depending on the conditions or where I'm at in cycling it up and down.

 

[powerscol]

Just used mine again yesterday - I run at idle and pull out ever few inches to clean. Sometimes I speed up to clean, but always use idle to dig. Saves a lot of time replacing shear bolts. Also at idle I can use low gear and move back or forward to keep the hole straight if needed.

 

[EddieWalker]

I start mine out at idle and increase as I feel the need. Usually slower is better, but I never want to bog down the engine, or drill so fast that I bury the auger. Sadly, I have yet to master this skill 100% of the time. Since you are new to it, and that Countryline auger is very aggressive, be sure to get yourself a really big pipe wrench to unscrew the auger out of the ground when it buries itself.

 

[kf4uda]

I run mine pretty much at idle. I am running it on a larger tractor than you are (75hp) so you may need to add some throttle. I would run it only fast enough to not lug the engine.

 

[bspeedy]

So personally, I control the rpms with my foot throttle and vary the rpms depending on the conditions or where I'm at in cycling it up and down.

^^This. At idle to dig, speed up with the foot throttle when cleaning out the hole to fling the spoils off. DON'T run it at full PTO rpm.

 

[NTG]

Awesome. I always forget about the foot pedal. That sounds like a good way to give it a little juice when backing out and slinging dirt. I'll go out in the middle of a field and practice digging a few holes and trying to keep them straight before I start in on a production hole. With the frost line so shallow here, I only dig 2' holes when I set a pole for something, so hopefully that'll help as well. Thanks everybody.

 

[bspeedy]

Pole depth depends upon the height of the pole. 2' depth is ok for an 8-footer, but too shallow for most others. I haven't looked it up, but I believe 25-30 percent of overall length is the recommendation.

 

[oosik]

Man, OH, man - I've got enough concerns/problems with the pto driven equipment I already have/use. I'm sure glad I don't use wood posts and need an auger. I'll let all you guys have the fun. I'm 100% T-133 posts on my fence line. And I use a manual pounder for that mile and a half of fence line I have.

 

[CincyFlyer]

We screwed an eight inch auger into our clay soil, and it took a giant pipe wrench with a ten foot extension (and an hour's wasted time) to unscrew it. If it had gone much deeper (and when it threads into the ground, it goes quickly!) I would have had to backhoe it out. Gotta keep it cutting, and often it's a slow speed and light feed, "following" the cut rather than pushing it, that works the best.

 

[CobyRupert]

We screwed an eight inch auger into our clay soil, and it took a giant pipe wrench with a ten foot extension (and an hour's wasted time) to unscrew it.

Gulp!

I ask this question on every post ole digger (PHD) thread, but no one has ever tried it (or answered): Cant you just use the pipe wrench or a bar on the PHD's PTO shaft, and use the PHD's gear box's ~4:1 mechanical advantage to back out the auger using a lot less force?

 

[k0ua]

Gulp!

I ask this question on every post ole digger (PHD) thread, but no one has ever tried it (or answered): Cant you just use the pipe wrench or a bar on the PHD's PTO shaft, and use the PHD's gear box's ~4:1 mechanical advantage to back out the auger using a lot less force?

I have seen several people mention doing that in threads. I don't really know, as I have never used a PHD. Well the PTO driven ones anyway. Dug plenty of post holes the hard way.

 

[CincyFlyer]

Gulp!

I ask this question on every post ole digger (PHD) thread, but no one has ever tried it (or answered): Cant you just use the pipe wrench or a bar on the PHD's PTO shaft, and use the PHD's gear box's ~4:1 mechanical advantage to back out the auger using a lot less force?

I never thought of it, but it may not have mattered if I had. Augurs are relatively cheap and widely available, and I can always weld on a new shaft (which it needs, and still hasn't gotten); gearboxes and PTO shafts, perhaps not so much "home repairable", they'll cost actual dollars (though the whole digger was maybe $400 or so). I have thought that "reverse gear" in a PTO would be nice, however. But engaging the clutch on something known to be stuck would be a heart-pounding exercise.
In this case, I turned the tractor around to try to pull the augur out with the FEL (utter failure, with more than a ton of lifting force!)

 

[powerscol]

Gulp!

I ask this question on every post ole digger (PHD) thread, but no one has ever tried it (or answered): Cant you just use the pipe wrench or a bar on the PHD's PTO shaft, and use the PHD's gear box's ~4:1 mechanical advantage to back out the auger using a lot less force?

Yes I have done it that way. Its slow going but worked when I could not do it the other way. However I put the wrench on the U joint at the head of the auger and not the PTO shaft. One other thing in digging is drop the 3PT very slowly (a notch at a time) as you go. This should keep it from getting stuck as easily. I also spray paint a line on the auger for how deep I need to go

 

[NTG]

Got it put together and dug some practice holes Saturday. Worked pretty well, I just need more practice keeping the hole straight.

 

[sdef]

I agree with all of the "use a slower speed" posts. PHD speed depends upon tractor PTO HP, ground condition and gear ratio of the PHD mostly, I think. If you drill enough holes, especially in hard ground, you most likely will get it stuck. I tried various tips from TBN including using a 48" pipe wrench. I even had to attach a chain to a pipe wrench on my first "stick" and driving the tractor in a partial circle a few times to get the auger starting to back out. Was really stuck badly with the flights having large rocks jamming them in place I think.

My ground is very hard clay and rocks- big rocks. I figured out a better way of backing out the auger on my property and that was to simply, gently, back the tractor up a couple inches and move it forward a couple inches- back and forth a few times while trying to lift the PHD using the 3PH lift lever. In a few minutes the hole will have loosened/enlarged enough to free the auger. Think of trying to remove a loose tooth when you were a child. Same concept and works great for me with little effort expended. I emphasize the word "gentle". My PHD is an ETA using the HD SpeeCo augers.

 

[Wayoldguy]

Gulp!

I ask this question on every post ole digger (PHD) thread, but no one has ever tried it (or answered): Cant you just use the pipe wrench or a bar on the PHD's PTO shaft, and use the PHD's gear box's ~4:1 mechanical advantage to back out the auger using a lot less force?

I have used a long (4') bar stuck through the U joint. I had to replace a zerks fitting that I broke off, but other than that it worked great! You get the gear reduction working in your favor. Only took me about a half hour to get back to work.

Take it slow and good luck!
Jim