How to Build a Hi-Tensile Fence - A Pictoral Guide
Building a Multi-Strand Hi-Tensile Fence
for the Beginning Farmer
Photo credits to: Rebecca Book
July 20th, 2009: I just returned from a few days of building fence in Iowa. Wow, they have some nice "dirt" up there compared to here in the Ozarks of Missouri ! I met Ethan Book in cyper-space nearly a year ago on his blog while checking links and search engine results for "powerflex posts". There were some interesting comments about fencing going on his blog at the time. His blog is called "The Beginning Farmer" and you can visit it at thebeginningfarmer.blogspot.com/
To make a longer story shorter, we talked over email off and on and I continued to check in with him over the next several months. Ethan had never built any hi-tensile electric fence before and I love to show people how to. So we finally got around to pick a date and I headed to Iowa. July 14th in the corn belt is usually hot, but we got lucky with some fantastically cool weather. Ethans wife, Becca, followed us around with a camera and got some really great photos during the construction. I'd like to pass these on to you as a step by step guideline on how to build a multi-strand hi-tensile fence. If you have not built much fence before, this should give you the basic steps in the process. So, here is a pictoral story of a 7 strand hi-tensile electric fence with wood corners and Powerflex line posts. Enjoy.
Ethan & Rebecca's farm is located near Knoxville, Iowa. When I arrived Ethan and Uncle Loren were in the process of installing the corner and end posts. I was a day early, so I jumped in and helped out. Working with "black" dirt was actually a special treat to me.
Above, Ethan cleans out an augered post hole, supervised by Uncle Loren, Hanna, and yours truly holding the post. This farm had been in CRP for the past 14 years and has some clay under great black topsoil. The holes dug easily to Ozark standards ! Vegitation at present is primarily switch grass.
The next step was to set the corner and end posts. This gives you points to attach your guide wire. In this case we were building a 7 strand fence, so we used the bottom strand as our guide wire. Your guide wire is very important with any fence and extra care should be taken to make sure that it is straight and tight. Once you have attached your guide wires to both ends a tensioner is installed and the wire is tensioned up. With dips and ridges it is important to walk the line and snap it up and down a few times to make sure it is perfectly straight. The wire dispenser (spinning jenny) is placed beyond the end post on a level surface. You can rather easily pull out a half mile of wire in this fashion, or you can use an ATV or other farm vehicle. This coil of hi-tensile wire is 4000' long and weighs around 100 pounds.
We made a some templates to mark our wire spacings on the end posts (and for later use to drill the powerflex posts) and drove steeples in partially to hold the wire in place. For this fence the bottom wire is 6? off the ground. The spacings are all 6? except for the top two wires are at 8? apart. Four of the wires will be electrified and 3 of them will be ground wires. They alternate with the top and bottom being electrified.
Next, we are going to attach our end strain insulators. To do this we use a piece of 12.5 gauge hi-tensile wire to go around the post and into the insulator. You can either hand knot these or use crimp sleeves. I prefer to hand knot, but we also installed some crimp sleeves so that Ethan could decide for himself how he wanted to do this task in the future.
In this photo, above, the end strain insulator is installed using the hand knotting techinque. It is now ready to accept the line wire when it is pulled out.
Above, Ethan is measuring and marking the Powerflex line posts. These posts are 66" long and we want to drive them, so that the top of the post is 48" off the ground. This will give us 18? of ground penetration. Our top wire will be at 46" on the post. Once we have them all marked we can begin driving them. We will stop driving at the mark and all posts will be 48" above ground level.
On this fence we also added some wood posts for line posts where there were terrain changes and transitions in the fence. The wood line posts were installed next along with our wood brace posts at the corners and ends. By not installing your brace posts before the guide wire is up, you can align your brace post, so that the fence wire runs straight.
After all of the wooden posts are set and aligned with the guide wire, you can begin installing the Powerflex line posts. We are using a 30 foot spacing on the line posts on this perimeter fence that borders a gravel country road. First we layed out and spotted the posts at 30' spacings.
On this first run of fence, I used a pilot driver,(blue tool down the fenceline) as I feel it gives you a straighter post. However, the ground was so soft and easy to work with here that the rest of the posts were just driven with a standard post driver. In fact the next day, Ethan and I drove about 70 posts in less than a half hour. (he was impressed, and I tried to keep my enthuasium to myself)
A view from the end post, with guide wire and line posts being driven in.
Next the brace posts and bracing were installed at the corners and ends. You will get a much straighter wire line if you wait to install your brace post after the guide wire is up and tight. Ethan had some HD steel U-bar that he used for horizonal bracing on these H-braces. We aligned it so it would be between the top and second wire, and out of our way. These bars had an upturned anchor point and were lagged into the wood posts. Two strands of #9 brace wire was used for tightning. A 20" length of Powerflex post was used as a twitch stick to tension the brace wire.
We have pulled the top wire in the picture above and working on the next one down which will be a ground wire. I decided to use wrap around insulators on the ground wires. It wasnt neccessary – we could have just wrapped the wire around the end posts. But, Ethan will be bringing in several different types of livestock in the future and he may want to electrify some of these ground wires in the future. So to give him some options and make it easy for him to redesign his fence in the future we did a few extra things from the beginning-just in case. Above, he is installing a crimp sleeve with a new Hayes 4 in 1 tool.
Here above, is Ethan pulling the fourth wire. We had some visitors during this day, Dave & Joyce, that came down to watch (and they helped out too). They are considering installing a simular fence on their farm. This run of fence was around 2000' long and had several transitions going around a curve in the road. So, there was some friction in pulling the wire. We put a pair of vice grips on the end of the wire to offer a handle to pull with. Some of the wires we pulled with an ATV, but Ethan being a strong young man, with a long stride, seemed to like walking it out, so I let him 
!
When one coil of wire runs out and you need to attach the next one during a pull, here is a simple joint you can do easily and quickly. Just install a C2L long crimp sleeve, leaving a foot of wire on each side, then hand wrap the ends. By leaving your crimp tool locked onto the crimp – it will give you some leverage on the wire to make the wraps. This makes for a strong joint and pulls thru the grass easily and without snagging on stobs or vegitation. Ethan picked up on this task rather quickly.
On a multi-strand fence like this one, I usually pull the top wire first and work my way down. After both ends are connected you can now tension up the wire. The tensioner should be located near the center of the fence run, rather than at one end. You will get a more uniform pull this way. If it is a very short run than its ok to mount the tensioner at the end. Pictured above is a round donut style tensioner (#EZT), that can be turned with a simple hand tool. While one person is doing this, another can be pulling another wire to keep the process moving.
Here is another leg of the fence, in which we used the #SCT1 spring clip tensioners. You will notice that the tensioners are somewhat staggered from each other. If staggered it is less likely that they could become tangled, should the wires get bounced around. As shown above, all 7 wires are now tensioned.
The next task is to drill the Powerflex Posts and install the cotter pins. While, this may sound like a time consuming job, it really does go quite quickly. For this we used the same template that we used on the end / corner posts to locate the wire spacings and keep them uniform.
You can use a cordless drill with a 7/32? bit. The posts drill quite easily. I have found that buying a good quality brad tip bit is a good investment and you can literally drill thousands of holes with one. If you have two people, then one can drill and the other follow installing the pins.
Here is a finished post with all seven wires attached with the cotter pins. The lower wires are spaced at 6? and the top 2 are spaced at 8?. You can vary this depending on the type of livestock that you are containing. For strictly cattle, a 4 or 5 wire perimeter fence is adequate.
Notice that we do NOT wrap the cotter pins around the fence wire. We want the fence wire to have free travel with NO restrictions. We simply bent the cotter pin tails around the posts and they are resting on the fence wire. I am not aware of any problems with cotter pins pulling out installed this way.
Above, Ethan (left) and I, have just hooked up our jumper wires at the end post at the driveway. I wanted to make sure that he had a good understanding of how to route his jumpers and wire feeds. With this 7 wire fence we have 4 hot (electrified) wires and 3 ground wires. We used insulated wire to make these connections. We used the CT4 open tap crimp sleeves to make the connections to the fence wires. We also drove a 6 foot galvanized ground rod to better ground the ground wires.
The bottom wire is not permantly electrified. We talked about this and chose to give Ethan some options. There will be times that he has only cattle along this fence, so it is not imperative that the bottom wires be hot. So he can easily use a pair of quick clips to power the bottom wire at times when he has baby pigs, goats or sheep along this fence. The bottom wire will likely incur a relatively heavy grass load.
We also used a wrap around insulator where the ground wires go around the wood post. The reason that we did this is so that, at a latter date, he decides to make some of those hot, he can do so without the grief of adding insulators.
Ethan chose the Stafix X6i Energizer. A good choice for his operation. It has 6 output joules and should give him plenty of power. It has a light bar plus a digital voltage display. This energizer has a fourth terminal (black) which is for earth monitoring – it will let him know how his grounding is working and if he should add more ground rods during dry soil times. The yellow terminal is a low output terminal, which he may use around the house, with 3 small children present. This unit could also be hooked up in bi-polar mode if he should ever chose to do that. This would put positive charges down the hot wires and negative charges down the ground wires.
The X6i also comes with a remote control to allow him to turn the energizer off or on anywhere on the farm. The remote also serves as a voltmeter and current meter. Additonally, it will run off of either 110V plug in or a 12V battery. In case of an ice storm or power outage, he could always run it off of a battery.
Before i left we installed 3 each 6 foot ground rods at the energizer, then at a few hundred feet away we drove in 4 more 6 foot ground rods for his lightning protection.
I really enjoyed my stay at Stoneyfield Farms,
and the hospility offered by Ethan & Rebecca Book.
(Rebecca is a mighty fine cook too, by the way.)