Why aren't splitter wedges pointed or serrated?

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KiwiBro

Mill 'em, nails be damned.
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If trying to minimise the force required to split a round, there are narrow wedges, sharp edges, multi-way wedges are set-back/staggered, but why not points or large serrations?

Is there any other shapes you think would work better than many of the wedges on the market nowadays?
 
Run a few hundred cords through and it becomes sharp/partially serrated naturally...at least in my experience with 2 splitters I've put that much wood through, but I never saw that it made much of a difference anyways.
 
If trying to minimise the force required to split a round, there are narrow wedges, sharp edges, multi-way wedges are set-back/staggered, but why not points or large serrations?

Is there any other shapes you think would work better than many of the wedges on the market nowadays?
likely not worth the drastic increase in cutting/machining costs... just wondering...do you just think of random questions to ask here? most of your posts I see are asking some sort of out of the ordinary questions...just wondering...
 
The main problem with splitters is the huge variety of sizes and shapes of logs necessitate a fast way to have different sizes angles and quantities of splitting surface.

It's like you need six different splitters, from teeny to gigantic. At least for the guys who scrounge what they can, people buying in fairly uniform size logs can get by with whatever fits "that" wood.
 
I've seen hand splitting wedges that come to a point. on a splitter though, I would think that it would make the splitting too unpredictable. with a flat straight wedge you can make the wood split the way you want.

siberian elm, american elm, and cottonwood split better going with the grain rather than across it. I would think that driving a pointed wedge into a stringy type of wood, would just make it splinter and split into 4 pieces and not separate the wood from each other.

just guessing
 
Hello,
My wedge on the splitter I built is very sharp.........I milled it to a point on a milling machine......it has worked great....is still sharp enough to almost cut you....and I have put many many cords through it over the years......I wouldn't want a dull or blunt wedge !!!!!

Henry and Wanda
 
Handheld splitter or machine? Handheld you may wish a sharper blade to make an easy start especially on large rounds being beaten with a sledge.

Machine wedges split by prying not slicing. A sharp blade and or serrations are for a slicing/sawing action. Splitter enters wood and pries apart the wood with a triangular wedge. The leading edge may even stop contacting the wood once inside the split as the side walls/back bevels on the wedge pry apart the split. Sharp edge on the compound bevel would just be prone to chipping and or nicking your hand should you bump it.
 
I use my angle grinder to touch up the edge on the wedge of my speeco every spring. I find that with woods like elm it cuts through most of the 'strings' rather than ripping them. It seems to go through crotchy pieces better as well.

Dave
 
Actually, I have seen wedges with sharp points that are welded to a flat wedge. Watching it work, I couldnt see any advantage to haing it done that way. I have also seen wedges that start with a short wedge and then step up to a taller wedge. The objective being to start the wood splitting with minimum effort and then letting the taller wedge complete the split. I dont see the advantage to that design either. With enough power, the wedge should split thru the wood anyways. Now on small cylinder splitters, some sort of starter wedge might be justifed.
 
I guess it would depend how hard you want to push the splitter, and if you use it as a cutter. Well it's not really cutting which is using a sawing motion, but pushing through the wood. Sometimes you get to that point that it stops prying and splitting and is pushing through the wood. If a cylinder mounted wedge, you end up pinching the wood between the wedge and the foot and it starts stressing the splitter beam/foot. In which case you want a sharp blade to cut/push through easier. I tend to not push my splitter this hard. I stop and reset for another attempt when I start getting that jerky jolting and metal stress sounds. Don't know if that makes sense, but described as best I could.
 
do you just think of random questions to ask here?
Hey, that's a random question.
I post the stupid questions nobody else dares ask for fear of flaming. It's a dirty (and thankless) job, but someone has to do it.

Have been looking at big don't-argue splitters, box wedges, etc lately. Thinking of completely changing the way I produce firewood next Summer down here. Wedges seem to have three main jobs:
  1. set up the initial tearing of the fibres
  2. promote their further separation
  3. cut through any non-parallel grain
I'm sure we have all seen the videos of splitters that seem to kick down to second stages while the round just seems to resist as the load builds up until it finally pops. That to my mind is a significantly undesirable trait. It's loading everything up more than it has to. I've a very sharp 2-way wedge that can slice across the grain pretty well and does a fairly good job of minimising the pop-force needed to persuade the round fibres to yield.

But then I'm wondering how much better the multi-way or box wedges might work if they didn't just stagger their business-ends but had a series of points to concentrate the forces. Some of the manufacturers must be using CNC/NC milling machines and experimented with different profiles a whole bunch, so maybe the long thin profiles are the best.

How about a sharp, scalloped leading edge that rises to a series of sharp points? Not so acute that the leading edges become weak, or the overall depth of the wedge becomes too deep, but instead of the round meeting a sharp thin line, it meets 5 sharp thin points, initially. Perhaps that would be too hard to touch-up in the field?

That's just one idea, I make no claim to it being a good one, and there are bound to be many others.
 
Good distinction. One I should have made. I'm talking knives mainly. Narrow splitter wedges or knives.
Indeed. I was thinking strictly wedge blade style splitters. I like the weird questions. They often teach the most. Beats not asking and learning the hard way.

"Didn't put enough dirt down. Saw it right off". -Bear Claw (Jeremiah Johnson)-
 
I split whatever I have - nice, clean, straight oak that pops apart before the blade is a quarter inch in, and nasty, gnarly, crotchy pieces. If it'll burn, I split and burn it. I like a sharp wedge because in the crotchy stuff it slices through the odd grain directions much better.
 
I think its a good question and it leads to its not only the wedge that is necessary for the splitting action but the baseplate too, a big flat baseplate that the wedge pushes the wood against will need considerably more grunt to split than a small pointed baseplate.
If you look at the split fire brand of splitters (i have one) the baseplate is set up to assist in the splitting action by having a leading edge being small and allows for the wood to "bend"a round it...
I will need to take a pic or two to illustrate this...
 
Looks like im not allowed to post a link that explains what im talking about from the splitfire site for some reason...

The splitfire advantage is explained on their site if you care to look...
 
I wonder about building the splitter so there's a fixed knife edge, and changeable wedges behind to accommodate different species. It seems like the "best" wedge design depends on the wood. Long, straight, parallel grains are better served by a compound wedge that "pops" the round apart faster. If the wood is split sooner in the cycle then more short cycles are possible. Stringy wood is better served by a sharp knife and narrow wedge. No amount of distance between halves at one end is going to speed the split if it's being held together by "strings" at the other. So reducing the energy required as the ram is run to full extension makes sense.

Maybe it's better to design the splitter for the wood you handle most often? Stacking straight wood is much easier than dealing with split knots or crotches and there's less wasted space, too. So if you don't often deal with a problem tree, why not just cut out the tough areas? Why design a tradeoff into the splitter?

It's like you need six different splitters, from teeny to gigantic. At least for the guys who scrounge what they can, people buying in fairly uniform size logs can get by with whatever fits "that" wood.
Exactly.
 
a friend of mine has an old splitter he built himself and the wedge is on the beam, and is swept forward so that the top point is an inch or two ahead of the bottom and with an extremely tired old 5 hp briggs that thing will split almost anything. its physics. a wedge that allows only part of it to contact the wood concentrates the available force on a smaller area. this can be overcome by more power, bigger engine or cylinder, but the point is the same (haha). watch a video on timbersports guys chop with their axes. they are trained from the beginning to swing in such a way that only a corner of the bit contacts that wood at first. If i ever get around to building a splitter, it will have a forward leaning wedge without a doubt.
 
You won't gain much by trying to "minimize" the "required" force... a better tactic is to "maximize" the "available" force.
This is done by keeping the available force centralized/localized in a small area directly in line with the cylinder rod. Large push plates and rod-mounted wedges don't do this... they actually rob or reduce force. My push "pad" is small, not much larger than the rod itself. It floats, tilts and swivels so near all the force is near always directly in line with the rod... even on angle-cut rounds. Most of the time my slide just floats, even rattles on the beam (i.e., loose on the beam, no binding, because it really isn't doing anything).

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