Need to set 300 wood fence posts EASY

[EddieWalker]

I'm 53 and in fair shape. I hate dealing with the 80 pound sacks of concrete, but I can handle the 50 pound sacks alright. Mixing the concrete first will give it more strength, so it's a good idea to do that for your corners and gate posts, but for everything else, just pour in a large coffee can of water into the hole, fill the hole halfway up with dry concrete, check you posts to be sure it's where you want it, add another can of water, and fill up the rest of the way with dry concrete. Then add more concrete to create a slope so water drains away from your posts. I sprinkle water on the slope so it will lock the mix together and I can shape it and make it steeper with my trowel.

I do not understand how adding gravel to the bottom of a hole will affect drainage? To me, it just creates a place for water to sit longer. If there is no space in the hole, water wont be able to get in there and sit. I wound not put gravel in the bottom of a hole.

Do not flood your hole and add dirt, that will never set up or compact. Too much water creates something we called "pumping" when I worked construction back in the 80's. It takes a very exact amount of water mixed thoroughly with the soil and then compacted to get dirt to become solid. When we had too much water, we would have to dig that dirt back out and set it aside, then bring in other dirt to do it again. We never tried messing with dirt that was pumping water, it's a waste of time.

Set a reasonable goal on how many you will do in a day. Ten? 20? whatever that number is, be sure to stop when you hit that goal and not over do it. Better to be able to keep at it every day, then to have to take a week off or more because of an injury.

 

[BHD]

I was setting a bunch of posts, and I made a tamper, using a air chisel and made a rod with a end welded on about 2" across, and it worked well tamping, but was slow, (do to the speed I went back to hand tamping), something like this but I cut it in half and welded a pipe in the middle to extend it.
Long Pneumatic Smoothing Hammer Chisel | S And G Tool Aid | 9114

I don't know if one of those air scrapers with a different end on it would work, like harbor freight sells, a "long reach floor scraper",

got the idea from the electric company that uses hydraulic tampers,

 

[jesseb3@att.net]

I set 15-20 posts for horse fence - the previous owner of the property probably did 50. All I did (and I checked his work - it was the same) was back fill with stone. I don’t remember a single post leaning when I sold the property 10 years later. Granted, four rail fencing doesn’t catch the wind much... not sure what kind of fence you’re installing. There was a post that leaned a little, but that was installed a few decades prior - still had wrought iron hardware on it.

 

[Carl_NH]

I would get 10-16 yards of crusher run - a mix of sand and gravel, or 8 yards of sand and 8 of 3/4" stone, then 15-20 bags of cement, then use your tractor bucket to make a dry mix and put a foot of the mix around the post in each hole then level the post. Then add as Eddie said a bit of water to each hole. Let this set up for a day or so then come back and add the rest of the dry mix and some water.

If you are doing this alone, make a jig to hold the post plumb using 2 2x6 and blocking based on the width of the post that lays on the ground from post to post then temporarily screw into the post, set the post and move the jig. Since your post span will vary just put in screws every few inches then set and level the post and repeat.

 

[747driver]

The stone creates drainage gaps to let the water wick down quicker. Now if you live in a well drained soil area then maybe stone is not used. I live in a heavy clay/orange colored soil. Putting stone in gets that post up so it doesn't lay in the wet soil when you have allot of rain. I am not a fan of pouring a solid concrete encasement around the post...it traps water between the post and the concrete. Better off using just crushed stone to pack it in.

 

[EddieWalker]

The stone creates drainage gaps to let the water wick down quicker. Now if you live in a well drained soil area then maybe stone is not used. I live in a heavy clay/orange colored soil. Putting stone in gets that post up so it doesn't lay in the wet soil when you have allot of rain. I am not a fan of pouring a solid concrete encasement around the post...it traps water between the post and the concrete. Better off using just crushed stone to pack it in.

Doesn't creating those openings with the stone allow water to remain in the hole compared to a hole that is filled solid with either compacted clay or concrete? How does stone help water drain through compacted clay when that's the perfect material for building ponds because it holds water so well? Adding rock just creates an area for that water to enter the hole and remain there longer.

 

[747driver]

Guess it just boils down to a personal choice. I just don't like the wood sitting on the soil. Kind of like a septic field drain line, the stone lets the water slowly dissipate through the stone. The clay we have here is like a sponge, it sucks the water up and dries out very quickly. Its more important at the top of the hole to not let water pool around the post, you need to slope that hole to get the water away.

 

[EddieWalker]

... Kind of like a septic field drain line, the stone lets the water slowly dissipate through the stone. The clay we have here is like a sponge, it sucks the water up and dries out very quickly. Its more important at the top of the hole to not let water pool around the post, you need to slope that hole to get the water away.

I agree about the getting rid of the water around the base of the posts. That's where I see the rot in every post that I've been hired to replace. I've never seen any rot at the bottom of a post.

I wonder if people who recommend putting gravel at the bottom of a hole and setting the post on top of that gravel are thinking it will do the same thing as a leach field, but not factoring in that a leach field only works in soil that is tested to make sure the moisture will drain out of that hole, and that moisture is brought into the gravel with a pipe without any wood materials anywhere in that trench?

I believe that the area around the post needs to be as solid of a plug as possible so NO moisture gets down into the hole. Concrete works the best for this, but it's not always needed and if the soil compacts well, then that is usually good too.