Nut splitters can have either a screw action or hydraulic action, with a ring-frame or C-frame design.
Ring frame nut splitter
As the name suggests the frame of a ring-frame nut splitter forms a ring that completely encircles the nut you wish to remove.
This type of nut splitter will often lack a flat anvil opposite the chisel, instead using the inside of the ring-frame to pinch the far side of the nut as the chisel is driven into the nut’s flat.
As the ring frame fully encircles the nut it is stronger than a C-frame nut splitter. However, this also makes the frame larger and can sometimes prevent the nut splitter from fitting nuts in confined spaces.
C-frame nut splitter
The C-frame nut splitter looks similar to a G-clamp. As one end of the frame is open and it does not fully encircle the nut it is possible to get a C-frame nut splitter into more confined spaces than a ring-frame one.
This nut splitter design usually comes with a rotating chisel that allows you to use it at various angles, which again enables it to access nuts you may not be able to with a ring-frame nut splitter.
The rotating chisel is first adjusted with a hex key so that there will be a minimal gap between it the nut and the anvil. Then keeping the chisel square to the nut’s flat the C-frame nut splitter is positioned over the nut, before the screw at the end of handle is turned to press the anvil up against the opposite flat of the nut. This is continued until the chisel splits the nut.
However, as the C-frame doesn’t completely encircle the nut it is not as strong as a ring-frame nut splitter. To combat this weaker design, the C-frame is made of thicker material than the ring frames of other nut splitters.
C-frame nut splitter with hydraulic screw action
These are the same as C-frame nut splitters except that instead of the screw acting directly on the chisel, it acts on a hydraulic ram in the handle which then moves the chisel.
Due to their greater internal complexity and therefore increased production costs, C-frame nut splitters with a hydraulic screw action cost more than a nut splitters with a direct screw action.
Why do some nut splitters use a hydraulic screw action?
The hydraulic screw action provide two advantages. Firstly, unlike a regular screw action that acts directly on the chisel, the screw of a nut splitter with a hydraulic screw action does not have to be aligned with the chisel.
This is because the hydraulic fluid in the ram can transmit the force from the screw around corners or at an angle to the second ram which then pushes the chisel. This means the handle of these nut splitters can be angled relative to their frame, allowing you to use them in spaces and situations where a normal screw action nut splitter would not fit.
The second advantage of a hydraulic screw action is that it provides a mechanical advantage, multiplying the original force applied to the screw.
Hydraulic nut splitter
Hydraulic nut splitters use a hydraulic ram instead of a screw to drive the chisel into the nut’s flat. This enables them to apply far more force to the chisel than can be achieved with a screw.
The greater force applied to the chisel along with harder chisel materials allows hydraulic nut splitters to remove larger and harder nuts than is possible with a screw nut splitter. This type of nut splitter is only found with a ring frame design in order to cope with the force exerted by the ram .
Hydraulic nut splitters are powered by a separate hydraulic pump. This pump can itself be powered by hand, electricity, pneumatically (compressed air) or petrol.
Hydraulic nut splitters cost considerably more than a screw action or C-frame with hydraulic screw action nut splitter. This means they are rarely used outside of heavy industry and very specialist applications.
