Patent Fence

Patent Fence

Created Tuesday 17 April 2012
horse high pig tight bull strong

Patent Fence Construction

Why Build a Patent Fence

There are many considerations to make when deciding on what fence you should use. In truth the patent fence should only be one tool in your fencing arsenal to be pulled out in specific circumstances. On my farm I have a mix of page wire, electric fencing and patent fences. The choice on fencing type depends on many things such as aesthetics (I'll see it everyday), longeitivity (I just need it for the summer), time (I need it yesterday) and purpose (sheep, horses, cows etc.), as well as cost and availability of materials.

For me, I have made a choice to build patent fences whenever I can. It is a long-term committment to improve the effectiveness, layout and value of my fencing infrastructure. There are a variety of reasons why I have made this choice, below are the main reasons.

A better option for Northern Ontario

In Northern Ontario we are blessed with beautiful trees, cold winters and large amounts. There is however generally a limited market for cedar trees that are not of sawlog quality. Quality cedar posts can still be relatively expensive since a straight grained cedar post-sized log with little rot is also perfect for making sawlogs with. This lack of market for low-quality cedar logs makes it relatively easy to get an abundant supply of logs that can be readily used for split rail fences. Often the tops get thrown into a load for free, and this bonus wood is perfect for use as braces or cross bars. This ready supply of logs makes it a very low cost option when compared to cedar post/t-rail/pagewire fences which are far more common.

Often when we feed our animals during the winter we do this in roughly the same spot and right next to a fence line. The animals walk on the snow and hay and pack it down and then it snows some more. Pretty soon your 4 foot high page wire fence is more like 1 or 2 feet and the animals readily hop the fence to go forage for food or roam about. Animals such as horses will pace a fence often creating a very similar situation. A patent fence can be as high as you like. I make mine 5 feet or greater in many cases, especially where I expect to be feeding in the area. The ability to modify the height of your fence depending on the animal type and snow depth is an extremely handy tool.

The winters here are long, when the summer comes, do you really want to be building fences instead of riding your horses or going hunting or fishing? Make use of the long winters and build fences during that time. A patent fence can be built just as easily during the winter as the summer. The fence is very sturdy and as the snow melts the fence will settle. I haven't had the need to modify my fences after they settle. But if you find changes are needed it is very easy to change a support here or a brace there in the spring of the year.

You might say, I've got a fence post auger for my tractor, I'll just go to town and sink a row of posts. Posts heave, rot and are hard to dig. Bury them 4 feet or more if you like, every year they seem to move up an inch or so, pretty soon they are leaning or there is a gap under your page wire where animals such as alpacas, sheep, goats or even some cows can escape through.

Heaved fence post

Posts rot, especially at the soil/air interface. You can use chemicals to treat these posts if you like but that increases cost and is not really something I want around my meat animals or expensive riding horses....never mind my kids. Another main reason why I avoid sinking posts is that I live on the claybelt. Ever dig a fencepost hole in wet clay? It's not fun and if you're not paying attention you can get the auger stuck pretty firmly.

Northern Ontario is not the praries. Fencing on uneven ground, marginal land such as boreal shield or claybelt swamps or through creeks is a reality and can be very difficult using conventional methods of fencing. Patent fences can traverse buried wires, rock outcrops, ravines and go across uneven terrain far better then pagewire. If the ground is not flat pagewire can be very difficult to deal with.

Patent Fence across a gully

Everyone who comes to my farm looks around and compliments me on my cedar patent fences. They tell me how nice they look and how effective they they seem to be. No one has ever come to my farm and complimented me on my nice new pagewire fence....or even my saging page wire fence with heaving and rotting posts. It is an aesthetically pleasing design, it looks natural and elicits a positive response from viewers.

Patent Fence

It's effective and safe.

Electric fences have their purposes as short-term, moveable internal boundaries for effective rotational grazing. Patent fences are a visual deterrent as well as a physcial deterrent and you can always be sure of it's effectiveness. Electric fencing can become quickly grounded out by snow and vegetation and sometimes animals (goats, sheep) will simply take the shock and keep going. As well, animals from inside the pen (horses, cows) or outside (moose, bear) can run through the fence and destroy it.

While electric fences offer the ultimate in fencing flexibility, I would suggest that cedar rail fences are not that far behind. I have move large spans of patent fences to allow dump trucks through or simply because the fence was in the wrong spot. How? By breaking the fence into bite size pieces of 2 or 3 self-standing spans the fence can be moved on a trailer or by hand with only minimal effort. There are no fence posts to dig up, it is like the fence was never there.

Patent fences are very versitle and can be adapted to any situation. In this example I had some already inserted metal rods (drill rods) that made perfect fence posts. I wanted to use this in my fence design which allowed we to forgo brace posts and skip every second A.

Using existing metal poles in a patent fence construction

If the patent fence by itself is not effective enough it is extremely simple to use screw-in insulators to string a strand of electric fence at the top or bottom of the fence. This will deter nibbling on the cedar and will buttress an already effective fence.

The fence looks imposing to an animal and an animal will see it and be deterred. It will not run through it on purpose or by accident. This fence can even be built to hold goats, one of the most difficult animals to fence in. As the saying goes, "If water can get through the fence, so will a goat" can be disproven with this fence because additional rails can be added so the fence will even be impermeable to kids and lambs.

Page wire has safety issues for some animals which are not a concern with patent fences. Animals may get a horn, leg or foot caught in the pagewire, there are no loose wires with patent fences. I have seen horses roll near pagewire and get their feet stuck in the holes between the wires and not be able to get up. Horses such as stallions can try to kick through fences. Their legs can pretty cut-up when a page wire fence is the seperating barrier. I've seen solid kicks hit a patent fence with no effect to either the fence or the horse. Simply put, if you value your horses you will avoid using pagewire for internal fencing whenever possible.

It is a Green

When considering whether something is green you must consider the alternative fencing methods and consider the energy expenditures required to produce the base materials and construct the fence. So lets compare patent fences to the common options:

1) Pressure treated or creosote posts

- With page wire - Must include the process for making metal and running it and twisting it
- Sawed boards - While you're supporting forest industry the extra processing requires energy expenditure
- Auger - Likely a gas powered auger is required to dig the fence posts

2) Patent Fence
- Cedar logs.
- Gas for chainsaw and truck/tractor. Far less wire than page wire
It should be noted that there are cedar rail fencing techniques which use no wire for the extremely green around us. These types of fences may require more regular maintenance and are much more difficult to get up to the standard of "horse high, pig tight, bull strong".

Last point. What is the best way to sequester carbon... by having young fast growing forests and storing the products as lumber in construction projects such as barns, houses...and fences. The wood decompose very slowly and stores carbon for longer then if the tree had been permitted to grow old rot and fall to the forest floor. Provided there is natural or artificial regeneration to replace the harevested trees, cutting cedar trees will result in an increased sequestration of carbon and reduce the carbon footprint of the farm.

How to Build a Patent Fence

Choosing your logs

An ideal log will have straight grain, minimal taper and little to no rot. The heartwood of a cedar is the most rot resistant once cured and so a hollow tree is less desireable than a whole tree. The straigt grain and minimal taper allows for a consisten and even rail once it is split. While it is always great to have an "ideal" log, any log can be worked with. This is because spans can be any length and rails of almost all lengths are needed. the middle of the A is about 3 feet, the x's 6 feet, the rails can be 8 or 9 feet and the braces can be 6 to 7 feet.

Cedar is the most common log to use. It is easy to split, is rot resistant, light and in many places can be found in plentiful supply. In northern Ontario I have substitued Tamarack (larch) with some success. The tamarack is a much heavier and harder wood and can not be easily split. Therefore, younger trees should be chosen in the spring of the year. If they are immediately peeled the bark comes off remarkeably easy due to the amount of moisture under the bark. If you wait and the trees dries the bark can be very very difficult to remove.

Extracting the logs from the forest can be quite labour intensive and will require you to have further equipment. I have used a tractor, trailer and chainsaw and selectively cleared forested area I wanted to turn into pasture. I then ran electric fence and put my sheep and goats in the area to forage and trim the lower branches of the remaining trees and brush. It's always fun to watch the goats push over a small tree or bush and the sheep eat the leaves....What team work! More recently I have chosen to purchase cedar logs of 8 to 10 foot lengths. I was able to make an excellent deal with the seller because I was indiscriminate in my selection of logs. An individual making a traditional fence would only be seeking the best logs as they would become fence posts. For me, I want it all, tops, rotten, tapered, small or large, it didn't matter.

Log length

Fence spans can be any length, I have made fences from 8 foot spans to 12 foot spans. There is no optimal span length and there are many considerations when deciding how long the logs you split will be. The longer the span the less wood required and the lighter the fence is. As a result I've had a length of 10 foot span blown over in a windstorm. I had made the fence extra tall and used 10 foot length logs. The height and lighness of the fence conspired and resulted in the entire span being blown over. Of course the beauty of this type of fence shone through even in this unhappy circumstance. The fence remained intact and was thus still a barrier for the horse it contained and the entire fence was easy for 3 of us to upright worse for wear.

Blown over patent fence, easy to upright

The longer the log the more likely you won't have perfect grain. Often the logs you get will have a taper and twisted grain. The longer the log the more these deformities will impede splitting. So the quality of your logs may be one of the deciding factors when deciding on length.

Will you be working alone or with others. Building fences is for me almost always a solitary occupation. If you will have people assisting you with hold logs then you might consider a longer span. If you are alone I would recommend no longer than a 9 foot span.

Standing next to a recently built fence

Materials Needed

The joy of this type of fence is the minimalist tools needed. axe, axe heads, maul, wedge, chainsaw, wire and fencing pliers. If you have a woodstove you likely own the majority of these tools already.

Splitting Technique


Splitting a log can be easy or hard. It depends a lot on how twisted the log's grain is, but the ease of the splitting can be significantly increased by perfecting your technique.

Most important is for the splitter to bend their knees when they are proceeding with the split. As your maul falls on to the wedge or axe head you should bend your knees to ensure the maul hits straight down. There are three reasons for this.
1) It maximizes the force of the impact on the wedge or axehead
2) If you miss with your maul or your maul hits a glancing blow and deflects off it will most likely impact the ground or log. If you do not bend your legs there is an increased possibility the maul will get deflected towards your boots or even worse...your shins.
3) If your wedge or axhead is only loosely set in the crack and this is only your first or second hit, it is possible the wedge could go flying. This happens when the wood is especially stubborn and instead of splitting it recloses the existing split and expels the metal. This can be serious and I have been hit in the shin by a flying wedge before. By making sure the momentum of your maul is straight down you will reduce the possibility that any flying wedges or axeblades will go towards you.

Aim is perhaps the hardest part to master and you should take your time to perfect it. Divide your aim into two plains, starting by mastering the forward/backward plain. This is easier of the two plains to master and really is based on consistency and solely on where you stand. You need to understand how long your reach plus maul is and stand that distance away every time. Once you consistently are hitting the spot move on to the 2nd plane.

The side to side plane is very difficult to master. You should start by lifting the maul to a 45 degree angle and hitting consistently the spot desired. This is admitly a more labour intensive way to split a log. Holding a maul at a 45 degree or even a 90 degree angle for periods of time can tire an individual out quickly and I would recommend doing this with a 7 1/2 pound maul to enhance longeivity and enjoyment. Unfortunately it is a necessary evil and those that don't take the time to master their aim will never graduate to the mastery of the full swing. Once you are consistent at 45 degrees, start swinging from 90 degrees. Most people stop here. They place their maul at their feet, heft it by bending knees and lifting with their arms and legs to a 90 degree angle. Pause to aim and swing downwards, bending their legs as the maul descends. If you feel comfortable with this splitting technique, thats great, it's an effective method and will allow many years of splitting enjoyment....however I have found that using this technique the max maul size I could use for extended periods was the 7 1/2 pound maul. If you wish to increase your splitting power and decrease the downward power expended to increase downward momentum for those really stubborn pieces you will need to graduate to the next level of perfect mastery. This level allows easy use of a 10 pound maul and involves a full swing. With this technique. Instead of hefting your axe to a 90 degree position in a vertical fashion, you swing it to a 90 degree position from behind and carry-on the movement with no pause at 90 degrees. There is no pause at the 90 degree position it is continuous from a position of rest to the impact on the wedge or axehead. The power using this technique with a 10 pound maul is awesome to behold and the effort is less then the previous technique of hefting to a 90 degree position for targetting purposes. Only with the perfection of ones aim can this technique be employed.

I started by using a 7 1/2 lb wedge and I would recommend the majority of beginner or novice fence builders to begin with this weight. I have since increased my weight to a 10 lb wedge. I have found that provided you have mastered your technique you actually require less work to split the logs. You are primarily using the weight of the maul to split the wood, with very little extra downward pressure required.

Reading the Grain

Each log wants to split in certain ways. Fortunately fighting this natural tendency is neither helpful or necessary. When building fences it is advantageous to have short and long, thin and wide rails. Nothing is worse then using rails that are too long for a brace or X and having to trim off the excess for use in a fireplace. Avoiding later trimming can be best minimized by good splitting, not by pre-cutting logs to different lengths prior to splitting.

Place the log on the ground, look at the ends or peel away some bark to see if there are any natural split lines present. If there are some that are roughly in the center of the log you should start with one of the splits. If the log has a substantial taper, work with it. Expect that some of the split rails will not run the whole length. Your intent is to maximize the log, not to have every rail be full length. If there is a substantial taper, look at the grain and knots and picture how you can have one to three full rails and multiple short ones for other uses. Work towards that objective no matter how the initial splits track in unpredictable fashions. Splits can be turned to a degree, but generally it is best to go with the split and avoid forcing something that isn't.

There will be times when you'll need to consider whether to have an extra large rail or two extra small rails. The answer is both are needed and it really doesn't matter. Do what you feel is best. At the end of the day there is an optimal weight needed for each span of fence. If you use a light rail for a middle rail, use a heavier rail for the bottom. The weight needs to be maintained for each span to ensure that wind or animals will not be able to tip it.

Final Thoughts

Building patent fences is satisfying and rewarding work, it feels good to split rails and assemble spans. You also have a thing of beauty (some would even say art) to show for your work. And it lasts! Some cedar rail fences are over 100 years old.

The sun setting over a patent fence