Followup questions: Hydraulics for logsplitter

Once again, many thanks for the very helpful information you have given me on hydraulics in general, and applying them to a log splitter in particular.
I now feel confident that I could go and buy the parts from Northern Tool to make a splitter, but as more than one person mentioned, that would raise the cost up to a significant fraction of the price of a new machine. My intention from the beginning has been to try to scavenge or scrounge as many parts as possible. So, a couple of followup questions:
1) I definitely see the advantages of the two-stage pumps, and if I have to buy a new one, I probably would go that direction. However, if I scrounge up a pump, it may not be a two stage job. I notice that, at least on NT's website, the non-two-stage pumps tend to be rated in cubic inches rather than gallon-per-minute. If I'm doing the math right, it looks like the cu. in. is the output per revolution, so that if one calculates RPM x cu. in., and divides by cu. in / gallon, one winds up with GPM. Yes? Or have I missed it?
2) Any specific suggestions about where to look for suitable hydraulic parts that might be available for scrounge prices? I've checked one nearby salvage yard, but the only cylinders they had were off of forklifts -- they were about 5' long and had a 5' stroke, which I somehow think would be overkill for my logsplitter! Alternately, would one of the "wholesale hydraulics" web sites actually be that much cheaper than NT for equivalent parts? What about an agriculture supply outfit -- would they have what I need at a cheaper price?
3) If I find scrounge-quality parts, what are the chances of needing to rebuild them, and what is involved in doing so? What can't be economically rebuilt?
4) This one may be a wild goose -- one of the links that I found via the replies I got from you all talked about a log splitter built quite some time back; it referred to the "original design" that used an old power steering pump as the hydraulic pump. It sounds like that worked, but produced relatively low pressure ( < 1000 psi). Any thoughts about this wild goose?
Once again, I look forward to your patient wisdom -- TIA!
Andy
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Andrew H. Wakefield wrote:

If you have to go with a single stage pump, the following might prove helpful:
< http://www.metalworking.com/DropBox/_2004_retired_files/2SPD_HYD.TXT
Ted
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On Mon, 21 Feb 2005 03:46:19 GMT, Ted Edwards
......and in reply I say!:
remove ns from my header address to reply via email

Huh! Bootstraps! <G> Clever! Thanks for that.
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1) Two speed pump is the only way to go on a splitter. You have a relatively small motor, a low duty cycle, and a no power needed return stroke.
2&3 ) You can check with a hydraulic cylinder repair place. they may have some rebuilt cylinders, they can tell you how much it costs to rebulild. Parts are cheap on these, as long as the rod doesn't have big gouges, you are ok. Other than that, just keep looking. But don't expect to get one for almost free. I've noticed that about the best I can do is about half price or a bit more figured against getting a decent deal at NT or a farm supply place.
4) Power steering pumps were commonly used for the early splitters. Most folk find that they just don't have the hp range you need and look for an upgrade. IIRC HP04*gpm*psi (better check that one!!)
Andrew H. Wakefield wrote:

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You're gonna have to pony up for the 2 stage pump. Also, for ease of operation, you need the 'logspitter' valve. You'll spend more on fittings and hose to russian-rig a different valve setup. JR Dweller in the cellar
Andrew H. Wakefield wrote:

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