Or you can order it for half the price he

https://ssl.lincolnelectric.com/lincoln/spmount/store.asp?PID=16&cat=7

Cheers,

Kelley

On Tue, 03 Feb 2004 06:33:25 +0800, Old Nick
wrote:

On 28 Jan 2004 06:45:19 -0800, (don schad)
vaguely proposed a theory
......and in reply I say!:

So I am not a complet naysayer:

http://www.okdpm.com/catalog/product...olume_III.html

ARC WELDED PROJECTS Volume III
This book gives you the plans, material lists, and instructions for
67 Welding projects!

AGRICULTURAL EQUIPMENT:
Adjustable pruning stand, heavy duty hydraulic tillage markers, quick
hitch, portable feed lot, spring loaded gate for calf roping, cattle
cake feeder, sub soil ripper, sheep blocking stand, tractor scraper,
box scraper, **Construction of a Custom built front end loader**, barn
fan, PTO driven buzz saw, hydraulically operated ditching unit, 60
foot spray rig, flat bed truck three point PTO wire winder.

US$14.99

I have Vol II and the plans vary in depth and quality, bt there are a
lot of useful ideas in these books for the $$.



Hi all.

I am scheming to build a front-end loader for my tractor, and I have
been looking into hydraulics. I have a couple of pretty basic
questions which I have generated after reading various sources and
looking through the catalogs. Any help/insight into any of these
questions would be much appreciated.

First question regards spools for open-center systems. Some Army
literature talks about open-center spools versus tandem-center spools.
Assuming a 4way with lines T (tank), P (pump), A and B (ports to
cylinder) my understanding is that in neutral an "open center" spool
connects all ports (A,B and P) to the T (tank), such that there
wouldn't be any pressure to the cylinder (i.e. it is floating in
neutral). A tandem open-center spool (in neutral) connects P to T (so
it is just passing through the spool), and closes off A and B, holding
pressure in the A/B loop.

In the first case, a loader w/ an open-center as described would come
crashing down when you let off the controls, whereas the tandem would
hold it's position. Looking at the catalogs I haven't seen a
reference to a "tandem" spool, but I have seen "open-center with load
checks", and further reading suggests that load checks will hold the
cylinder in position.

So, is what I'm calling a tandem spool the same as an "open-center
with load checks"? Does a load check in a spool close off the lines
in neutral?

Second, if you have a spool that is rated for say 25GPM, will there be
any problem running it at a lower GPM? Say 12GPM or 5? Will it still
function properly/safely?

How is pressure controled in the system? Is it just a matter of
setting the relief/bypass values, and the lowest one will control the
pressure (although I guess this would depend on how it was plumbed)?
Most seem to say that they function from 1000psi to 3000psi - does
this mean I can make any combination of pressure/flow rate in the
system to achieive my goals or fit my pump/equipment?

What is the difference between a welded versus a tie rod cylinder?
Pros/cons?

Finally, in parallel spool decks is the flow simply divided between
the open spools, such that everything will work, but at a lower speed?
And pressure in all A/B lines is the same (so all spools get there
input from the P line)? In series is it that the flow out of one
spool feeds into another spool (so input is from the T line), and we
get a decrease in the pressure (with the same flow)?

Thanks in advance for your help. I appreciate any and all comments
and info.

don

************************************************* *** sorry
remove ns from my header address to reply via email

Spike....Spike? Hello?