20ton log splitter press

[Nick Brodsky]

Hey people does anyone have any experience using a 20ton log splitter to make a forging press.

 

Thanks for the help.

[Irondragon Forge ClayWorks]

I saw one in operation and to my way of thinking the ram was way too slow for forging, it can be done though but I wouldn't want one.

[Fowllife]

Just like anything else, it depends on what you start with and what you expect in the end. If it has a big enough 2 stage pump it could be plenty fast. Both of the splitters I use make a complete 20" or 24" stroke cycle in around 15 seconds. Mind you those these were both custom build, I have never used a factory built splitter to know how fast they are. I also have never tried to use one as a forging press.

[Jbradshaw]

How fast should a ram move to be useful as a press? I imagine the pump on one of these could be upgraded if needed and still come in at a much lower cost than a commercial press. 

[ThomasPowers]

Depends on how you plan to use it: Welding is different from drawing, is different from punching/drifting, is different from ornamental work, is different from bending,...

[Frosty]

If you use a detent valve the ram will stay where it is when you let go of the handle so you can position the die close to the stock and not worry so much about speed.

An automatic return valve is good on a log splitter but not so good on a forge press as it returns the cylinder all the way when the lever's released. 

These are plumbing change outs but you have to be sure you have the right valve type and specifications for the machine. The below link is a good primer so you'll have a handle on what to ask and what the counter guy is saying. 

https://northernhydraulics.net/catalog/hydraulics-101.html

Frosty The Lucky.

[Jbradshaw]

Thomas I asked the question generally as the statement about it being to slow was given generally. I have seen statements on several occasions that a log splitter moves too slow, but never a speed referenced that would be considered appropriate, for any function. 

I have a log splitter (used as a log splitter but I may modify it for double duty down the road) and the ram moves at about 4 inches/second when not under load (based on cycle time). I’m haven’t timed it under a load. That is faster than the ram speeds I have seen reported on commercial presses so I am confused as to why so many people call them too slow. Maybe Frosty is on to something with the detent valve and people are actually calling the cycle time too slow, not the ram speed?

[Fowllife]

A quick check shows that a stock MTD log splitter has a cycle time of 19 seconds with a 25” stroke, or 2.6”/second average. I suspect older units are slower. The one I referenced earlier would be around 3.3”/second. If yours is 4”/second it would do a complete 25” cycle in 12.5 seconds. That’s quite a bit faster then the average log splitter. 

As for the detend valve, both of the ones I use are a 3 position valve, extend, retract, and home. There is no reason that type of valve would not work for a press. I have not personally used a splitter that would automatically retract without being able to stop mid cycle. 

[EDL]

Here's a splitter I've considered as a viable conversion candidate:    commercial link removed

I picked this one primarily because it specs a pretty fast 9.7 second cycle time (pump is 2-stage 14GPM).  However, it does also state that it is "auto return", so it might entail a replacement control valve for press operation (unless the auto return function is actuated  by a spring or some simple mechanical means that could be eliminated).  Also must consider an electric motor to replace the gas engine (unless you really want to run your press on a gas engine).  I think a 3HP TEFC motor would run it adequately, or a 5HP motor would do so without question.  Replacing a gas engine with an electric is not a 1:1 requirement for HP (google it to understand why).  Of note though, concerning the pump, most of them, at least in the sizes we're talking here, are flow rated at 3600 RPM.  Most lower priced TEFC motors (i.e. sub-$200 range) are rated at either 1725 or 3450 RPM, so with the 3450 motor you are losing 150 RPM to the pump.  I don't know precisely how much that lower RPM will affect flow rate as you have a large and small displacement pump in a 2-stage pump.  The given flow rate is typically given when both pumps operate to give you the faster no load speed and then kicks over to the small displacement pump only to get the high force output (and obviously, travel speed slows way down at that point).  Without calculations or knowing more specifics on the pump in this application, I'd say the difference isn't significant.  If you really want exactly 3600 RPM fro your motor, you can get different RPM speeds in TEFC motors, but from what I've seen, anything other than 1725 or 3450 is pricey, at least twice the price or more.  There is also the option of pulleys and ratios if you really want to go down that route.

With all that considered, the question is one of economics.  Would it be cheaper to buy a pump, motor, cylinder, control valve, filter, hoses, fittings, all the steel, etc and just scratch build it?  I think that'd end up a bit on the more expensive side, even using cheaply priced parts.  For example, a 2-stage 16GPM (2 more GPM translates into slightly faster cycle time) pump can be had for $129.99 new.  A 4" x 24" log splitter cylinder runs in the $225-$250 range (or opt for a shorter stroke cylinder...do you really need a 24" stroke?), a 4-way, 3 position hydraulic control valve that can handle up to 25GPM is around $125.  There's still the question of the electric motor, and all the steel to build the beam, ways, ram, fluid tank, filter, hoses, etc.  I think the scratch build ends up costing more.  Even if you have to replace the control valve on the log splitter, you still end up ahead buying the splitter and converting it.  Also, you can re-purpose or sell parts you remove, like the 16" DOT approved road wheels and tires, the control valve (if it gets replaced) and even the trailer hitch.  Not a significant recovery of money, but just those three things alone would potentially net you a $150ish in the want ads, which would cover the cost of the control valve replacement if needed.  Anyway, you get the idea.

For the cheapest route, then certainly find everything used, but you'd have to find the right deal.  In my area, just searching local want ads and craigslist over a period of time there are no good deals to be had.  What I would consider viable used units, the sellers want new or near new prices.  Even beat to death units they want more than half the price of a new one.  There are a few "custom built" ones (i.e.home made) that look like they wouldn't crush a beer can, much less put out any tonnage of pressing pressure, and the sellers think these things are gold plated.  For me, at least, it seems a new unit, such as the one I linked above, is the route I'm going to have to take.

Even buying a brand new splitter, any necessary ancillary or replacement parts, and converting it would still give you, in my opinion, a more than adequately functional press for a lot less than commercially made "forging presses."  After all, there are literally hundreds, if not thousands of videos of people doing this type of press.  If it didn't work well, or was more trouble than it was worth, then that many people wouldn't be doing it. 

Then, there are those that will insist only a proper commercial press is worth owning and using....

Edited October 29, 2019 by Mod30
commercial link removed

[EDL]

Oops, sorry about the commercial link.  To see the splitter I mentioned, 

[Frosty]

For $900 and another $100 +/- is pretty cheap for a working piece of machinery that'll last the rest of your life. Here's a thought, rather than replacing the gasoline engine how about buying longer lines and putting it outside or in a sound proof box? The box will be more convenient but you'll have to make sure there is positive air flow for cooling so add on a small blower fan to the price tag.

If speed is important take a look at, the "Power King, 42 ton kinetic splitter." It covers that 24"+ in about a second and hits with 42 tons of force. The driving force is a pair of fly wheels driving a pinion gear and a heavy duty rack on the pushing plate. If resistance stalls it it automatically retracts.

For safety it REQUIRES TWO HANDS TO OPERATE. So a mod would be something to hold the work while you operate the ram. I sure would NOT disable the two hand feature! Search and watch the video, this thing is inherently dangerous but OOH DADDY what a forging press!

Okay, I'm not really suggesting the Power King Kinetic, mods and operation aren't trivial nor for the beginner, it's more of a pro shop piece of equipment making closed die production runs. Watch the video and see what I mean.

My point for bringing this beast up is price vs. utility. If you're going to invest in a hydraulic forging press you want it to be worth the money. Some of us have the knowledge, skills and experience to build one even evaluate and rebuild dumpster dive components. I haven't checked recently but used to cost about $20 for the seals and gaskets to rebuild a hyd pump/motor, the state tossed them because labor cost more than a new unit, same for valves and rams.  

The splitters I've looked at at the local Home Depot run from around $100 to $3,500 for the Power King. Personally I'd save my shekels and buy a mid range splitter and modify it. Clamp on bottom and top dies are too easy to describe and wouldn't require changes to the splitter so I wouldn't have to rent one when I need to split wood. Mid range at the Wasilla Home Depot runs around $1,300 - $1,700 per and the rentals sell old machinery all the time better they'll sell parts and heck rebuild it for you. 

Heck you could just make the clamp on die mods and rent a splitter. Now there's a cheap forging press for you! A day's rental. 24 hrs, runs around $100 +/- locally. 

Everybody really over rates ram speed when it's PSI that does the forging, it'd have to really creep for the work to cool fast enough to effect things. So what if you can't get 3 pushes per heat? Compare the amount of work done per push to hand and hammer. Hmmm? Seriously, stop the retract 1/4" - 1/2" from the work and it'll be squishing for you in what a second or so? 

Frosty The Lucky.

[EDL]

Frosty, exactly.  Your idea of remotely mounting the engine is certainly an option.  Of course, along with selling the wheels/tires, trailer hitch, selling that engine too, you could recoup a decent little chunk of change to reduce purchase cost of the splitter.  Rebuilding cylinders too, it really all depends on what and how much work you want to put into it.  You could source every part used and hit the scrap yard to get the steel for the beam, build your own totally from scratch (and I know a few machinists who would consider the idea of building a cylinder from scratch as a weekend challenge).  

I think jbradshaw above sort of hit the nail on the head with his question concerning travel speed.  Even looking at commercial forging presses, I don't see a lot of information of ram travel speeds.  You are so right about it too, obviously, you don't fully cycle the ram for every press, just move it somewhere slightly above the work to reposition and then press again. 

Concerning a kinetic splitter...that ain't a press, that's a horizontal power hammer!  :-)

If travel speed on a log splitter is really THAT much of a concern, it's not difficult to change that.  Get a higher flowing pump or even a regenerating valve.  Obviously, a 2-stage pump is key, need to generate the pressure without massive power input that a single stage would require. 

I did see a video of a guy who built a 60-ton press using two 30-ton rams.  I imagine he might have a specific use for that kind of pressure working massive pieces of steel, but that's just crazy for the average home shop hobbiest.  I can just see that "Yes, we make your damascus knife from billet to ready to heat treat...all in one press cycle!"

[picker77]

Not sure if there would be sufficient gpm, but could the aux hydraulic system of a 30-40hp tractor power a homebrew shop press?

[ThomasPowers]

If it can lift a round bale it should be able to put some squish on hot steel!

[picker77]

Oh, it can do that all right. But I use it mostly for road maintenance and brush/tree clearing. The rear aux hydraulics are  currently hooked up to provide tilt/trim for a 5-1/2' box blade, or (by swapping aux hoses) run a small two-finger grapple on a toothed bucket for grabbing & lifting logs, rocks, stumps, etc. to a max of about 1100 lb. If the pump provided sufficient volume, I suppose I could run a pair of long lines from a press located inside the shop out the door to the tractor, turning the tractor into sort of a very large 4WD mobile power pack. This is not a big farm tractor, just a little JD 3032 compact, and as I recall the pump is only 6 gpm or so at around 2200 psi. Maybe not enough flow there for forging. The tractor is normally parked inside the shop, but of course I'd have to move it outside to power a press to keep it from freaking out my CO detector, not to mention killing the press operator.

[ThomasPowers]

Oh one of "them"....

[Fowllife]

Picker - Will it work, yeah I'm sure you can figure something out to make it work. In my opinion though it's really not worth the risk, and work involved.

I'm not familiar with how the hydraulic pump is set up ion that tractor. Most small tractors are not set up to run the remotes at constant flow, and if yours are controlled by an electric solenoid you may not be able to. If you can't lock your remotes on to full flow you will need to control the press from the tractor. Also, does it provide that flow and pressure at idle, or at rated RPM's?

A PTO pump would probably be a better option then using the tractor hydraulics. This option would let you keep the press fluid in a separate system. If you use the tractor hydraulics I would make sure you wire in a murphy switch tied to a hydraulic temp gauge. The hydraulic cooling capacity of the smaller tractors is not all that great.

The biggest thing for me though is cost. A electric motor setup is fairly cheap compared to a new hydraulic pump for your tractor. If you figure fuel and depreciation into the equation electric is a no brainer as long as you have power close. I would probably even buy a cheap Harbor Freight Honda knock off gas engine before I went to the work of using tractor hydraulics.

[picker77]

Well, it was mainly just idle conjecture, not gonna happen for lots of reasons, some of which you mention.