"Old Nick" wrote in message
news
On Thu, 29 Jan 2004 01:20:19 GMT, "Toolbert"
vaguely proposed a theory
......and in reply I say!:

OK. You give a good impression of being able to put the truth across.

I have a backhoe. I find that some of the controls for the digger
(slew in particular) are way too fast. I wanted to place a flow
limiter in the circuit, preferably adjustable within limits, so that I
do not have to be _so_ careful with the slew controls when working,
especially in confined sirrounds.

I was told this would not work, as it would force fluid back through
the pressure release/return all the time and heat the fluid too much.

The system is quite large for the machine (industrail, not farm setup
on a little Massye 40) and has about 30-40 litres of tank capacity. I
spend a lot of time "feathering" the controls anyway, which is going
to have the same effect, no? Is there really a problem?

I haven't had the pleasure of operating anything with high-quality fine
touch control. It's second nature to just throttle down. I spent a bit of
last summer operating a little excavator within inches of a building and
tried hard to not punch any extra holes. Spent a lot of time near idle.

I think with a farm tractor you just deal with its limits. It'll have
enough other limits. If the hydraulic system is not properly sized or
designed it'll still get the job done, just with more risk of breaking
something. (An engineeered system will have all the cylinder bores sized
to the mechanical design so full pressure won't bend things.)

Adding a flow limiter is beyond my depth. I like the suggestion about
going with smaller hoses, though there is more risk of blowing the hoses
with pressure surges from mechanical shock.

Bob