Hi Mike
I didnt think of that (how efficient the flywheel was on weird wood instead of straight) I expect you get a spectacular explosion if it all gives way with all that knettic fly wheel energy flying about and wanting to go sopmewhere
. I expect they built in a system to cope with that like the sacrificial bolt they put in the flywheel to PTO connection on a hay baler so it gives way if theres too much strain from wet hay? I reckon all firewood splitting systems would ideally like to work with nice straight clean coppice (no side branches or crotchhes) I know one lad as uses a finnish log processor he has 2 stacks of logs-1 that WILL go through it (nice clean coppice) and another that WONT (everything else, and that pile is big) I know another lad as uses the tapered screw method on a PTO on his tractor, he swears by it it will do most stuff (except elm) His Dad said more than once they had to get the elm log off the screw with a chain saw as it was fully in, had not split and had stopped working.Is american elm as wild and non splitting than english elm? What do they do to stop the log spinning once the screw bites, is it held in a pneumatic clamp or something?
I saw a drawing of greek olive press where they had a long boom arm with stone weights to get pressure for to get the oil out, I keep trying to imagine a design that worked some how like that, turn around almost as quick as your average pnuemattic splitter, but easy to build, quiet, no gas needed. Maybe somehow raise the boom, then let it drop, a bit like the old water powered trip hammer's?. There was another spliitter on youtube, the bloke was raving on and on about it but never showed it working?
It had a splitting blade that come down vertically powered by a gas engine.
cheers Jonathan
On those wood-screw type splitters, they usually have a braced bar sticking out on the one side next to the spinning splitter part. You rest the wood on that bar, and it keeps the whole log from spinning. Yes, you can get wood "stuck" on it - if it doesn't want to split. Then you have to stop it, and go in and cut all those twisty wood fibers still holding it together. Like most mechanical wood splitters, they work best on straight grained easy splitting wood. The tough twisty grained wood is always the hard stuff to split - like elm, and oak knots. The hydraulic splitters tend to work best on those.
One drawback to those woodscrew type splitters is that you have less control over the size of the pieces you are splitting the wood into. It tends to splinter out into smaller slivers a bunch more.
There are hydraulic log splitters that can be tilted upright to use. You just have to roll the log over to it, and then it pushes the wedge down through the wood. Saves you having to lift that big chunk up onto the machine. But they tend to have the splitting wedge on the end of the hydraulic cylinder arm instead of a flat plate, and then push that wedge through the log - instead of pushing the log into the wedge. Just a different variation, but most common ones push the log into the wedge.
The big problem with a swinging arm kindling splitter are those mechanical laws we learned back in school - of levers and force. The longer the lever you have, the more force you can apply over a short distance near the other end. But the "handle" end also then has to travel a greater distance. The end of a 2 foot long lever will only really have to travel between 1 and 2 feet on the end. But if you make that lever 4 feet long, the end will have to swing in an arc at least 4 to 6 feet - for the same amount of travel down near the pivot end. You do get several times more force you can apply, but you have to "run" a lot more at the other end to do it. It's still a nice thought, and could possibly be tweaked up some more to work better, but those old laws of physics start kicking in fast. Adding some extra levers and linkages could increase the force without some of the total length, but the splitting wedge portion won't travel vary far with each swing.
At an old farm sale years ago, I saw one part of what had been a home-made log splitter. I still shiver just thinking about it. Nobody wanted to buy that piece. Even the scrap iron junk buyers hesitated. The thought of it and how it might have worked just made people's blood run cold. The person had taken a large flywheel and axle from an old machine, and had welded a splitting maul head onto the outside rim of the flywheel!!!!!! The only way it would have worked is to have that flywheel spinning, and then quickly jam a log up next to it before that splitting maul head spun around to hit/split that log. Yeah, I still get shivers thinking about it!
But now I kind of wish I had bought it at the farm sale for a buck - just for a "conversation" piece. And as a warning about the potential dangers of some ideas!
Elm is elm. Most is pretty tough to split, with lots of twisty grain. But sometimes you get a tree that splits fairly easily. When this happens, I usually have to stop everything, and make sure just what type of wood it really is. So occasionally you can luck out - occasionally.
Just my humble thoughts to share. Take them as such.
Mikey - yee ol' grumpy blacksmith out in the Hinterlands
p.s. Yes, taking a little break from doing normal daily physical work sure lets you know how fast you "go soft". Athletes deal with this all the time - which is why they do so much training even during the "off" season.
