Greg9504
Member
Here's a few pictures of the hydraulic stone splitter I am finishing up building. It is similar to a log splitter in lots of ways. Main difference is there is a bottom blade. It uses two hydraulic cylinders, 6" bore 10" stroke. For blades I used the log splitter blades from Northern Tool, as I had read that someone else had used them for a stone splitter. I would not recommend this as after only a few splits they are already showing lots of wear. But it was worth a shot. I'll eventually replace them with some tool steel, perhaps AR400 plate.
The feed table is a section of roller conveyor I picked up used (2.5" diameter rollers, 11/16" hex shafts, 4" C-channel sides). It is hydraulically raised when the top blade is raised. The cylinder was installed so that at full extension the roller tops sits just above the bottom blade. As the upper blade is lowered the table lowers (pivots at the rear) by gravity (cylinder is installed as single acting) so that the stone rests on the bottom blade. I had originally had it lower hydraulically but forgot to take into account that the cylinder would continue to try to retract after the table came to rest... so it was trying to pull itself apart, doh!
The splitter frame is made from 10" I beam (1/4" thickness), with 10" C-Channel (15.3 lbs/ft), bolted together with 7/8" grade 8 fasteners, 16 top, 16 on the bottom. The top is also welded. The bottom can be lowered 6" to allow for larger stones. I also welded 1/4" flat bar on the I-Beam where it is bolted so the bolts go through about 3/4" of steel.
The hydraulics come off my dump truck which has a HIAB crane on it which had an extra section on the control valve. The relief valve is set at 2500 psi, which would have given me about 70 tons of splitting, but I now have the divider valve in there so its probably not going to make that now.
I had a few setbacks along the way:
- cylinders did not move in sync. One cylinder would finish it's stroke before the second would move (I did have unequal length hoses from the tee). Solved this with a spool type divider/combiner valve. May go to a rotary type as I may be losing a significant amount of PSI that is dropped across the valve.
- My upper blade guide did not engage enough of the blade to prevent it from twisting. This was made worse by the cylinder synchronization problem.
- I had originally installed the cylinders so that they "floated", thinking that as soon as they started to "push" they would push flat against the supports. Again since they were not in sync I had a lot of movement, allowing the blade to twist.
To solve all of these problems I welded the cylinders to the upper supports, extended the upper blade support (both horizontally and vertically), took 3" out of the height of the upper blade (had them water jet cut), and made the guides out of 3" angle instead of 2.5".
Things I would have done differently... instead of using off the shelf cylinders (Princess Auto here in Canada). I would have had them custom made, with a flange plate on the top, and a clevis mount on the rod. As it was I had to fab up my own clevis mount as these cylinder rods had a screw in fitting on the end meant for a press.
With "solid" type blade this is intended for flat stone: sandstone, limestone and sawn granite slabs. Probably would not work that well on round field stones. The opening is 36" wide, with 24" of cutting blade. Max height is 20 inches with the lower bladed in the lower position. Although realistically I think I'll be lucky to split stones 16" in height. In the raised position I can fit 14" stones between the blades.
Will do some more testing tomorrow with larger stones... oh and yes I need to get that one hose made a little longer.
The feed table is a section of roller conveyor I picked up used (2.5" diameter rollers, 11/16" hex shafts, 4" C-channel sides). It is hydraulically raised when the top blade is raised. The cylinder was installed so that at full extension the roller tops sits just above the bottom blade. As the upper blade is lowered the table lowers (pivots at the rear) by gravity (cylinder is installed as single acting) so that the stone rests on the bottom blade. I had originally had it lower hydraulically but forgot to take into account that the cylinder would continue to try to retract after the table came to rest... so it was trying to pull itself apart, doh!
The splitter frame is made from 10" I beam (1/4" thickness), with 10" C-Channel (15.3 lbs/ft), bolted together with 7/8" grade 8 fasteners, 16 top, 16 on the bottom. The top is also welded. The bottom can be lowered 6" to allow for larger stones. I also welded 1/4" flat bar on the I-Beam where it is bolted so the bolts go through about 3/4" of steel.
The hydraulics come off my dump truck which has a HIAB crane on it which had an extra section on the control valve. The relief valve is set at 2500 psi, which would have given me about 70 tons of splitting, but I now have the divider valve in there so its probably not going to make that now.
I had a few setbacks along the way:
- cylinders did not move in sync. One cylinder would finish it's stroke before the second would move (I did have unequal length hoses from the tee). Solved this with a spool type divider/combiner valve. May go to a rotary type as I may be losing a significant amount of PSI that is dropped across the valve.
- My upper blade guide did not engage enough of the blade to prevent it from twisting. This was made worse by the cylinder synchronization problem.
- I had originally installed the cylinders so that they "floated", thinking that as soon as they started to "push" they would push flat against the supports. Again since they were not in sync I had a lot of movement, allowing the blade to twist.
To solve all of these problems I welded the cylinders to the upper supports, extended the upper blade support (both horizontally and vertically), took 3" out of the height of the upper blade (had them water jet cut), and made the guides out of 3" angle instead of 2.5".
Things I would have done differently... instead of using off the shelf cylinders (Princess Auto here in Canada). I would have had them custom made, with a flange plate on the top, and a clevis mount on the rod. As it was I had to fab up my own clevis mount as these cylinder rods had a screw in fitting on the end meant for a press.
With "solid" type blade this is intended for flat stone: sandstone, limestone and sawn granite slabs. Probably would not work that well on round field stones. The opening is 36" wide, with 24" of cutting blade. Max height is 20 inches with the lower bladed in the lower position. Although realistically I think I'll be lucky to split stones 16" in height. In the raised position I can fit 14" stones between the blades.
Will do some more testing tomorrow with larger stones... oh and yes I need to get that one hose made a little longer.
