PHD advice?

[ronbo3]

I am building a barn for my Kubota L2800, and I will be renting a 3pt PHD to dig the post holes. I will be digging in sand/clay soil, not close to trees, and I want to put my 4"X6" posts 3' in the ground. Do I need a 9" or 12" auger? Also, I'd like to hear any tips, hints, or info on how to use the PHD, since I've never used one before. Thanks!

 

[slowrev]

Are you planning on concreting the posts in or tamping them ?

 

[chim]

I only ever used a PHD once, and without incident. The best advice I can give you is:

A. Don't even THINK about getting near the spinning auger.

B. Make sure you know exactly where any underground utilities are before drilling into the dirt.

Good luck with your project................chim

 

[GerardC]

A 9" should be fine. Use the clay to repack the hole(s). This is what I did and it works out good. Concrete will rot the posts over time.

Have someone help you align the PHD after you start the hole. It will drift and you must readjust to assure a straight hole. Once you get the feel of it, you can do it by yourself. Go slow at first and you'll be fine. G

 

[MikePA]

<font color="blue">...4"X6" posts 3' in the ground. Do I need a 9" or 12" auger? </font>
With 4" x 4" posts, I'd recommend a 9" auger. Since you're using 4" x 6", I'd recommend the 12".

Remember, too, that you need room in the hole to tamp whatever you back fill the hole with. A 9" auger would only leave 1.5" on the 6" side of a 4" x 6". You also need room to tilt the post to get it level as well as line it up with the other posts in the fence line.

 

[zuiko]

I would use a 12" because it gives you some room for error.

When you drill, do it at idle speed and clear the hole regularly (by pulling it out and giving it some throttle) so it doesn't screw into the ground.

 

[ronbo3]

I had planned to put a 40lb bag of concrete in with each post along with tamping it in with clay. Will concrete rot a treated post? I have heard both yes and no, but everyone in this area tells me to concrete them in.
When using the PHD, how do I keep it plumb? Do I check for plumb after digging every 6-8", and move the tractor if needed?? How high should the RPMs be to use a PHD? I appreciate the advice to start slow and stay away from the turning auger!!

 

[MikePA]

<font color="blue"> I had planned to put a 40lb bag of concrete in with each post along with tamping it in with clay. Will concrete rot a treated post? I have heard both yes and no, but everyone in this area tells me to concrete them in.</font>
The concrete attracts moisture and that's what accelerates rotting.

<font color="blue">When using the PHD, how do I keep it plumb? Do I check for plumb after digging every 6-8", and move the tractor if needed??</font>
I just eyeballed the auger for plumb before I started digging, then checked it once or twice. Since the 3ph moves in an arc, you usually have to pull the tractor forward slightly to keep the auger plumb. Since the hole is bigger than the fence post, there's room to adjust the post for plumb.

<font color="blue">How high should the RPMs be to use a PHD? I appreciate the advice to start slow and stay away from the turning auger!! </font>
I started slightly above idle and increased rpm only occasionally.

 

[familyman]

I assume you're using pressure treated posts? If so, don't worry about the rot...the posts should last longer than you will. Pressure treated lumber is used in vast quantities in most parts of the country and goes off the lumberyard shelves so fast it's still soaking wet when you buy it. This means it will shrink alot over time, although the end in the ground will dry less than the rest. Concrete? I've concreted PT posts many times for decks, mailbox posts, etc., and they always stay solidly in place, but for your application I think it would be overkill -- a good tamping would work fine. The main advantage to some concrete in the hole, as I see it, is that the next morning when you pull the braces and start to build the posts will be rock solid. It's just alot of extra work and cost.
Let me know how you make out. I'm building a small pole barn in spring '05. I haven't used a PHD on my L2800 yet, but I'm excited about not having to wrestle with a 2-person PHD anymore!

Charley

 

[cisco]

Basically, I agree with MikePA. I've placed about 40 posts (4X4s & 6X6s) 2 years ago, using ground treated wood (it's green tinted when purchased) and concreting such into place -used 300 lbs of concrete around posts which bear the fence gate (6X6s), and 80 lbs around the rest (4X4s). Nothing has moved, at all.
The PHD, quite obviously, has to move in an arc, so you can either drill a hole much bigger than you'll need for the post and concrete, so you can line up the post in the slightly crooked hole, or use a smaller auger if you move the tractor slightly during the hole drilling, to keep the auger near vertical (if a FEL, just place the lower blade of such on the ground, and move the tractor slightly as the PHD drills down). No big deal either way.
Caveats - don't let anyone within a foot or so of the auger (or pto shaft); start slow with the rpm on the auger, and speed up depending on the soil; pull the auger up briefly every foot of digging (depth) or so, to avoid augering the rear of your tractor into the ground (a neophyte "gentleman farmer" neighbor of mine managed to lift the front wheels of his tractor off the ground with an errant auger - had to back out the auger shaft with a large wrench to get his tractor back on solid ground - go figure).
Good luck - you'll have fun.

 

[Henro]

I may be repeating but I'll say it anyway.... /forums/images/graemlins/smile.gif

Auger size needed is dependent on how good you are. If you are good a 9" auger would work fine for your posts...I'm not that good, so I used a 14" auger for my 6x6 posts... /forums/images/graemlins/blush.gif

If you are like me, you will get some hole that go in on a bit of an angle...having a larger hole is good in that case. Remember it is easier to put back in than to dig out with a manual post hole digger and digging bar!

The other reason I used a 14" auger was I wanted to put a 12 inch round cement stone in the bottom of the hole to rest my post on...

Water is not a problem with wood, contrary to common belief. It is moisture that is the problem. Where do posts that hold docks up rot? At the water line. Wood saturated with water will last a VERY long time. It is the damp wood that is condusive to rotting...so the worry with concrete is in my opinion not one of attracting water, but rather one of the concrete keeping the water away...and allowing the wood to dry out and stay in a damp condition...similar to the water line on a dock post...that being said, I concreted my posts at the bottom...and manually tamped in the dirt above. I wanted the posts to be set firmly when I did my framing...no shifting please... /forums/images/graemlins/smile.gif

Err on the large size for the auger. Your back will thank you when you don't have to manually correct minor errors in hole placement.

Or should I say, when you don't have to correct too many errors...

Or course one who is Good can get by with a six inch auger for a six inch post I suppose...whoops...I think I put one too many "o's" in Good... /forums/images/graemlins/grin.gif

 

[johnk]

I use a 9" auger and it's mainly in rocky soil. Works great tough if you think how a 2 man auger would be to try to hold back from the torque. Bust a lot of shear pins but thats better than bustin the tractor.

more pics. http://users.adelphia.net/~gizmo/

 

[Rick Jay]

Hi,

Use the 12" auger. A 4" x 6" post has about a 6.5" diagonal measurement (assuming the post actually measures 3.5" x 5.5"). With a 9" auger, that leaves less than 1.25"" on each corner for error. In my limited experience, that's not much. If your ground is hard and/or you've got a good assortment of rocks, it's hard to drill an accurate hole. I think you'll save yourself a lot of time and aggravation by using the larger auger.

~Rick

 

[v8dave]

Lots of comments about posts and concrete. The way I was told to concrete posts is to make sure the concrete does not form a bucket to hold the post in a pool of water.

A concrete bucket would make the conditions Henro points out where the post breaks off at the surface of the water. And, since the concrete top is usually at the soil level it looks like the concrete is the problem. Well. . . it is, but with a few preventative measures it won't be.

Make sure the bottom of the post can drain. Jamb it into the ground at the bottom of the hole, throw in a few inches of dirt then the concrete. Or, better yet, as I was told, throw some gravel in the bottom of the hole, place the post on the gravel, put a few inches of gravel around the post, then put in the concrete. Either way any water soaking into the post has a way to drain out the bottom.

Dave

 

[johnbilt]

</font><font color="blue" class="small">(
Water is not a problem with wood, contrary to common belief. It is moisture that is the problem. Where do posts that hold docks up rot? At the water line. )</font>

Henro

You always seem to have a way with words. I love it !!! Great picture with the beers. Cheers !!

Ditto on the advice. I drilled many a post hole with our old Massey Ferguson growing up. A helper keeping an eye on the auger angle is a big benefit.

John

 

[dixiedrifter]

If your worried bout moisture, then take a couple sheets of plastic sheeting and put on the end of the post, then sink it into concrete.

 

[markct]

i think ya missed the idea, plastic sheets on the end of the post would do exactly what we dont want, hold water and moisture around the post like a bucket.

 

[Kevin_in_VA]

I paint my posts (using an oil based paint) from the bottom to about 8 inches above the ground level to prevent moisture retention before I put them in the hole.

The paint is cheap if you buy "oops" paint from the local Lowes, Home Depot, etc... I painted a 12' x 12' shed using two gallons of matching Behr "oops" from Home Depot that cost me a little over 5 bucks.