Didier splitters

[david_fillman]

Heat will be main issue, larger hose will help in that a bit but the constriction of 1/2" ports on the ram will be the main culprit. Speed- larger hose won't affect that again because of the ram ports. If the valve is all 1/2" also just money down drain with step up and step down adapters. Eons ago I rebuilt my splitter ( after bending mutiple areas including the 2" thick foot plate) my valve is 3/4" ports and hoses also but the ram ports are 1/2" my speed didn't change that i noticed but the unit runs much cooler. If my pump goes or the ram then I will jump to 16gpm ( 11 gpm now) and a ram with 3/4" ports. ( finding 3/4" ported ram is more dollars than the 1/2") Iirc the 16 gpm pump is still a 1/2 output port just at higher pressure.

I am happy with cutting my splitting time by more than half. I am not going to spend $100 in hoses chasing 2 seconds. The valve has 3/4" NPT in and out ports but the cylinder and valve work ports are 1/2" NPT. The real restriction are the 6 JIC -8 fittings at .39" inside diameter. -12 fittings would get 1/2" NPT up to .53" ID and 3/4" NPT up to .61" ID.

 

[triptester]

While there are industry standards for external thread and taper diamensions the internal diamensions vary greatly.
This pic shows the same size and style of fitting but different manufacturer.

 

[david_fillman]

While there are industry standards for external thread and taper dimensions the internal dimensions vary greatly.
This pic shows the same size and style of fitting but different manufacturer.

I only use JIC 37°, military spec MS51500 hydraulic fittings on my race cars, tractor hydraulics and log splitter. I worked for a pipe fitting manufacturer for 8 years as a mechanical engineer. I specialized in fluid dynamics testing of US, Canuck naval ship set and nuke plant pipe fittings.

The US military does not allow dimensional variations.

I agree that non MS spec stuff is all over the place.

https://landandmaritimeapps.dla.mil/Downloads/MilSpec/Docs/MIL-DTL-18866/ms51500.pdf

 

[david_fillman]

The stock CROSS valves on the Didier's with steel hard lines, are like most I've seen.
If you change out valve to another, that either pulls or pushes the spool, will change port output.

I had to use flex hoses to use the new valve (NOT CROSS) I installed, or if you reuse the solid steel lines, will work backwards.
Like your 2nd. picture shows.

It depends if the pivot on the valve handle pushes or pulls the spool.
The CROSS valve pulls spool out when moving forward. (pivots on bottom), my new valve PUSHES the spool in, (pivots on top)

Since I installed the new pump that cut the cycle time in more than half I decided to try and figure out why the Cross valve advances automatically when splitting wood. I always thought that was dangerous but now it is obviously dangerous.

After researching the Cross manuals I realized that the valve has a double detent spool (#28) that holds in both forward and retract directions. Cross calls for a single detent spool (#32) that only holds on retract and kicks out when the ram gets all the way back.

I swapped out the double detent spool (#28) for a single detent on retract spool (#32). I also had to flip the handle pivot bracket (#10) so the link (#4) is now on the top and swapped the "A" and "B" hoses per the Cross manual.

Only took half a century but now the valve works correctly.