Home brew splitter Warnings

[Jamess67]

As some of you have already read in another thread, I built a log splitter.

Recently I was splitting some large rounds when the motor expectantly stopped. At first I figured the motor seized up. Thank the Lord that wasn't the case. I pulled the motor to find that it was free and in good working order. The problem turned out to be in the pump.

When I built the splitter I didn't have room for a suction screen in the design. I flushed the oil tank with compressed air and then two gallons of oil. I added magnets to the bottom of the tank to catch any metal shavings. This apparently didn't work because the pump picked up several metal fragments which in turn locked up the pump.
After pulling the pump (sheared the key on the shaft when it locked up) I was able to work out the shavings and the pump again was turning freely. I was able to look inside the inlet and see the gears which looked intact and not chipped up so I decided to reassemble the splitter and give her a try.
I added a remote suction filter (10 micron filter for now) to avoid any future incidents. To my surprise everything functions great.
The moral if this part of my story is that you must have some sort of suction filter/screen when doing a project like this.

In continuing my function check I loaded up the splitter to check the bypass pressure and overall pump function. Everything worked GREAT. However, as you can see in the pictures below, the pump worked so well that it was able to shear all 8 1/2" carriage bolts that held the wedge to the I beam. That was scary for me and my 12 yr old son. Not to mention one of the side clamps fell on my big toe. OUCH
The second moral of this LONG story is to make sure you are using the proper strength hardware in your design.
Please work and build safely.

 

[triptester]

The next thing you will want to change is the non-hydraulic fitting on the control valve witch is not designed for the pressures it will be subject to.

 

[SmokinPiney]

No wonder the wedge broke, Your not supposed to split 4x4's sideways! :ahhh: haha just kiddin. Glad to hear you and your son didn't get hurt when the bolts broke. We learn somethin new every day...

 

[Jamess67]

The next thing you will want to change is the non-hydraulic fitting on the control valve witch is not designed for the pressures it will be subject to.

That non hydraulic fitting is on the low pressure (return) side.

I replaced the bolts with standard 1/2" grade 5 bolts so I should be good for splitting 4x4s sideways...lol

 

[kevin j]

carriage bolts are typically grade 2, and much of the china hardware isn't even meeting that spec.

I would though change your 10u suction filter to a 100 mesh strainer. There are spin ons you can put right on in place of the filter. Suction strainer is a debate in industrial fluid power, and suction FILTERS are almost always a no-no. too much chance of cavitating the pump on cold startup. Gear pumps more tolerant then piston pumps, but still not so good for mobile equipment that can be outside. A suction strainer keeps out gross trash like you found, and a return filter cleans the oil to prevent long term wear.

nicel built structire from the limited pics.

k

 

[triptester]

Kevin, who makes a spin on suction strainer. My tank has a 1 1/2"npt opening that only allows for a 1" in tank suction screen. I was hoping to change to a 22 gpm pump.

 

[Jamess67]

The only reason I have a 10 micron suction filter is because they didnt have anything else. I will order a 140 micron ASAP.
After getting everything back together I removed the 2 large magnets I had on either side of the suction hole of the tank. Then put an telescopic magnet in the tank and pulled out even more metal shavings just waiting to trash my pump again. So between the magnets and the filter ( 140 micron) I should be good.

 

[fossil]

I think with the kinds of forces we're talking about in a hydraulic splitter system, I'd have gone with Grade 8 everywhere. You could order exactly the fasteners you need from Gardner-Westcott. I've done a good bit of business with them and they sell good stuff. Rick

 

[trafick]

Northern has a 149 micron metal mesh suction filter for applications where you cannot put a suction strainer in the tank. #4014

They also have a couple of suction strainers that you may be able to retro-fit. #4010 and #4011

But all of these may be too small for your application GPM wise.

 

[jrousell]

You should use hardened higher grade bolts on something like that.. carriage bolts are not intended for something like that.

 

[kevin j]

Northern has a mesh element for the 1 inch threaded post filter size, and I think also one for the 1.5 inch post. I think Surplus Center/Burdens also has them.

Yes, your in tank port strainer would be too small.

11 to 16 gpm, the 1 inch size is too small I think. Figure on the 'rated' flow they advertised and go half that flow or less for suction.

Rules of thumb, pressure lines 7 to 14 ft per second velocity, suction 2 to 5 ft/sec, so 1/3 flow for suction applciation is fairly safe. Higher flows = higher pressure drops. Adding 5 or 10 psi to return line is negligible. Adding 3 or 4 psi to suction side can be problems with cavitation.

I am sure there are NAPA ones to order, but I don't have the info.
Almost every filter mfr makes assorted elements for both base sizes, just have to find the local suppliers.
Search on Zinga, LHA, Filtration Products Corp, they are common.
Parker, Schroeder, and the other industrial suppliers do some spin on, but don't compete well in the low priced market.

kcj

 

[Jamess67]

I ended up getting a 144 micron filter for $16.95 shipped. That was the cheapest I could find after 2 hours of searching. So Its on it way. Couldnt find anything from Zinga, or Napa. Ended up with a Cim tek 70077. My filter housing is only 1 inch . It is what it is, my suction hole from the tank is only 1/2" ID, and it works fine. I might have been a little faster but hind sight is 20/20. It works and thats all that matters. Ill fix that defect on the next one I build. LOL Ill start it up tomorrow and let it idle for a while to clean the fluid before I change out the filter. No sense co throwing out a brand new filter.
Yeah I agree the carriage bolts were wrong, but thats what I have seen on all the other splitters out there. So lesson learned, wont do that again.

 

[boostnut]

Did those bolts get pulled thru the holes they were installed in?

 

[Jamess67]

Yes they pulled thru the wedge plate to what you see in the pics

 

[boostnut]

Wow, glad I welded mine together.

 

[John_M]

Fossil is right: Use at least Grade 8 or harder bolts throughout. Also use nylock or other locking nuts for the vibration protection. Nylock nuts with split lock washers should also work well.