Crunching a few numbers on the concept of using my mini excavator to split wood. Hydraulic system is capable of 2600 PSI. Plugging that number into common cylinder sizes I come up with about 8 tons capacity with a 3” bore and 15 ish with a 4” bore. Seems low compared to the advertised ratings of commercially built splitters. Am I missing something or are their numbers inflated somehow like these “3 hp” air compressors that somehow run on 120V outlets? Mini is rated at 21 HP and 10 GPM flow so it should have a reasonable fast cycle time.
I should ask also what the typical splitter cylinder size is and also the peak pump pressure? Seems splitter companies are not forth coming about that kind of information for one reason or another.
FWIW The one my son has isn’t at all fast but is used principally to split very large or gnarly rounds and works very well suited for it. Edit: I reread your post seems you want to use the mini ex hydraulics to power the splitter like a hydraulic remote off a tractor?
My thought is to make a splitter that attaches to the mini in place of the bucket and use the auxiliary hydraulics to run it. Run the splitter from the mini seat. The idea is no lifting logs onto a splitter.
Bingo! They way overinflate their tonnage numbers, and upsell customers to more expensive splitters with "more power" that is seldom needed...especially with a good cutting edge. That's the key...a sharp/fairly narrow knife, instead of a blunt/wide wedge that many box/farm store splitters have. 2600 psi is fine... that'll give you a little over 9 tons. I'd go with a 3" cylinder though, otherwise that 10gpm pump will lead to really slow cycle times with a 4". A large diameter ram helps speed things up too...faster return stroke time. Calculator here... Log Splitter Hydraulic Cylinder Force Calculator
Looking at just splitter pumps for sale I see some are rated for up to 4000 PSI. That somewhat explains how these commercially built splitters get such high tonnage ratings, but even then the math suggests there is some blue sky in the advertised rating.
I don't think any of the box/farm store splitters run 4k psi...most are in the 3-3500 psi range. But I highly suspect that they don't actually run them even that high (engines too small in many cases) because if you look at the rating on the hoses, sometimes it's less than what it would take to make their supposed tonnage ratings.
Yes! And, very few hit 3000K I use a 35 Ton, but I had a 22 ton that did nearly everything I needed it to years back. I split some big S#!T too!
