Peggie Hall wrote in message . com...
We must be talking about two different washers...'cuz the one I'm
referring to isn't a Huskey, it's a Kaercher...and R 1750 psi it's
definitely a lot more powerful than any car wash wand.

Possibly? Most of us know the economical HD-sold unit as what I
described; it has the same pressure rating BTW. It's unlikely there
is a substantial difference at this low level of unit.

I use mine to
take the winter mold and mildew off my house--and it reaches the eaves
on the second floor with no problem...also to take the "green stuff" off
my deck...it blasts it right off. And also got water into any place in
my boat's bilges that any other liquid could get into. However, I
wouldn't even think of using it to wash my car...I'd be afraid it would
damage the paint. I woudln't use a commercial pressure washer on my boat
either...at 15000 psi, they can damage gelcoat or paint.

Please let me share some things about pressure washers & pressure
washing with you:

Commercial PW's don't operate at 15,000 psi - that is industrial
shipyard waterblasing equip't used in the drydock, and even those are
more limited now over the past 20 years of OSHA & its foreign
equivalents. Pressure rating also means little by itself - the
important matter is the velocity at which the water meets the surface
- i.e., a combination of pressure, nozzle size, pattern, pattern size
& operator technique.

Good PW operation takes training & practice. The effective & proper
application of the jet to a surface to be cleaned is 90 degrees, which
gives the highest impact velocity & is the only way to keep it uniform
throughout strokes. Uniformity is important both for even results &
to avoid damage to the substrate (especially wood). It is similar in
concept to spraying paint. Wood, especially, should *never* be
pressure-washed at any angle but 90 degrees, to prevent or minimize
grain lifting/damage.

A higher pressure & higher-volume (i.e., real-world) pressure washer
does a far better & faster job than these lower-, low-volume consumer
units, not because any higher impact velocity is employed in the
cleaning - it isn't. But a much better-designed nozzle with the
specific pattern needed for the job and the higher *nozzle* pressure
are used to give a much wider sweep, which not only makes the work far
faster but give far more uniform results.

For example, whereas the toy 1750 psi unit on a 10' x 50'
pressure-treated deck that needs real cleaning (weathering or heavy
algae) will only clean 1-1/2" or so per pass on its fan pattern, and
can take 3+ hours (don't ask how I proved it) a real unit will clean a
whole plank width at a time with a much faster stoke - and very
uniform, *without* as much risk of biting into the wood as the toy
unit's nozzle which must be moved more slowly & less uniformly, and
held more closely to the work. This same deck job takes 15 minutes
with the real tool & is much more thorough. The little 1750 unit
makes *more* wood damage due to its slower cleaning speed, at any
impact velocities that qualify as an attempt to pressure-wash. The
small unit is also much more fatiguing to operate, since its wand does
not make enough recoil pressure to balance the outstretched arm as the
real tool does, and must be held far longer.

Whatever you are reaching up high or far away with it (I used the same
or similar unit to knock down a high hornet nest this way while using
it as a window-rinser), this isn't pressure washing, and the same may
be done with other inexpensive types of hose nozzles that don't need
to be powered. The only way you can pressure-wash your house siding
is to be on a ladder or manlift at the same height where you can apply
the spray at 90 degrees near the surface in a controlled, even sweep.
Anything less than this is just hosing it off from a little further
away.

Another problem with these units is their detergent dispenser, which
cannot be metered & which lays out the product very quickly (often
expensive product that is more effective when more dilute, or that
needs to be to avoid damage).

And it is indeed the same sort of pressure delivery as the car washes,
at least those here in the northeast. You needn't fear washing your
car with the 1750 unit, and most who own one mainly use them for it.
However, for cleaning a really dirty vehicle, hand-washing removes
stuck-on crud faster & better than the 1750 PSI washer. I have proven
this several times with my own vehicles. Same rule applies, too:
always perpendicular to the work. Not only will the paint be safe,
but for removing difficult things like baked-on pitch it is much
easier on the paint (but slower) than hand-cleaning. For that matter,
someone who knows how to properly operate a real pressure washer can
safely wash any car with that, too.

There is a lot more that can be said about this kind of unit, but I'll
sum up by saying that though I have one, whenever I have a real
cleaning task to do (such as wood house siding, hull cleaning,
masonry, PT decks etc.), it is far cheaper, faster & better for me to
rent a real unit. For even lighter-duty jobs, a 3-stage 5,000 PSI
unit run at 2,500 - 3,000 is an efficient joy to use.

After a lot of use of several kinds of pressure washers, I am
convinced that using any that have less than a 3-stage pump & cost
less than $1,000 on sale is a false economy, timewise, results-wise
and costwise, for any application. At $40 - $50/day versus the outlay
for the consumer machine divided by this rental rate, one can do
several times the cleaning that the consumer machine will do in its
useful lifetime.

I'm at somewhat of a loss as to how you reach every part of a boat
interior with any kind of water pressure tool, when the wand is
necessarily long and cannot be bent, and there are many inaccessible
voids or other areas not possible to spray directly with a straight
wand. No direct spray = no cleaning. I think the dirt just flies off
at you no matter what you use because of your magnetic personality,
Peggy. ;-^)