So many times I could have used one. Everyday light duty B&D drill has
one built in. It can and has been handy. But I'd like to get a decent
one. Trouble is, even the ones that push say $75 (I know they can cost
hundreds) have an accuracy spec I think sucks for a laser. If I recall,
lasers are coherent light and are pretty darn straight. Light travels
straight unless it's bent or distorted and laser light doesn't disburse
in general. Also if I recall, the intensity and directness of laser light
depends a lot on the mirrors generating the exit beam.

How the hell did I get off on that tangent...?

Anyway, I see accuracy of +/- like 1/2" in 100'. Saw a $35 Sears brand
one today (not self leveling) that was +/- 1/2" in 30 ft. Crimus!, I can
almost do better than that eyeballing.

What exactly is the "accuracy" spec?

For a self leveling one, does this mean the two endpoints at the spec
distance and be off up or down by 1/2"?

How about one that is not self leveling...basically shooting a straight
line. Does it mean the beam can be bowed +/- 1/2" at any point alone the
line?

Red Green wrote:

So many times I could have used one. Everyday light duty B&D drill has
one built in. It can and has been handy. But I'd like to get a decent
one. Trouble is, even the ones that push say $75 (I know they can cost
hundreds) have an accuracy spec I think sucks for a laser. If I recall,
lasers are coherent light and are pretty darn straight. Light travels
straight unless it's bent or distorted and laser light doesn't disburse
in general. Also if I recall, the intensity and directness of laser light
depends a lot on the mirrors generating the exit beam.

How the hell did I get off on that tangent...?

Anyway, I see accuracy of +/- like 1/2" in 100'. Saw a $35 Sears brand
one today (not self leveling) that was +/- 1/2" in 30 ft. Crimus!, I can
almost do better than that eyeballing.

What exactly is the "accuracy" spec?

For a self leveling one, does this mean the two endpoints at the spec
distance and be off up or down by 1/2"?

How about one that is not self leveling...basically shooting a straight
line. Does it mean the beam can be bowed +/- 1/2" at any point alone the
line?

The specs are related to the quality of the bubble levels used in the
units, the quality of the factory alignment of the mirror or laser
mount, etc., not the laser beam itself. The laser beam will spread a bit
with distance, giving a larger spot size because the beams from laser
diodes aren't as well collimated as those from other types of lasers.

On Mar 5, 8:42*pm, Red Green wrote:
So many times I could have used one. Everyday light duty B&D drill has
one built in. It can and has been handy. But I'd like to get a decent
one. Trouble is, even the ones that push say $75 (I know they can cost
hundreds) have an accuracy spec I think sucks for a laser. If I recall,
lasers are coherent light and are pretty darn straight. Light travels
straight unless it's bent or distorted and laser light doesn't disburse
in general. Also if I recall, the intensity and directness of laser light
depends a lot on the mirrors generating the exit beam.

How the hell did I get off on that tangent...?

Anyway, I see accuracy of +/- like 1/2" in 100'. Saw a $35 Sears brand
one today (not self leveling) that was +/- 1/2" in 30 ft. Crimus!, I can
almost do better than that eyeballing.

What exactly is the "accuracy" spec?

For a self leveling one, does this mean the two endpoints at the spec
distance and be off up or down by 1/2"?

How about one that is not self leveling...basically shooting a straight
line. Does it mean the beam can be bowed +/- 1/2" at any point alone the
line?

If you need a Laser level, retire or get glasses. That crap is a
gimmic for the gulible.

It would sure be interesting to see YOU accomplish floor flatness
requirements or install a drop ceiling in a Wal-Mart or similar
competitively without a laser.

--
______________________________
Keep the whole world singing . . . .
DanG (remove the sevens)




"ransley" wrote in message
...
On Mar 5, 8:42 pm, Red Green wrote:
So many times I could have used one. Everyday light duty B&D
drill has
one built in. It can and has been handy. But I'd like to get a
decent
one. Trouble is, even the ones that push say $75 (I know they
can cost
hundreds) have an accuracy spec I think sucks for a laser. If I
recall,
lasers are coherent light and are pretty darn straight. Light
travels
straight unless it's bent or distorted and laser light doesn't
disburse
in general. Also if I recall, the intensity and directness of
laser light
depends a lot on the mirrors generating the exit beam.

How the hell did I get off on that tangent...?

Anyway, I see accuracy of +/- like 1/2" in 100'. Saw a $35 Sears
brand
one today (not self leveling) that was +/- 1/2" in 30 ft.
Crimus!, I can
almost do better than that eyeballing.

What exactly is the "accuracy" spec?

For a self leveling one, does this mean the two endpoints at the
spec
distance and be off up or down by 1/2"?

How about one that is not self leveling...basically shooting a
straight
line. Does it mean the beam can be bowed +/- 1/2" at any point
alone the
line?

If you need a Laser level, retire or get glasses. That crap is a
gimmic for the gulible.

On Fri, 06 Mar 2009 07:48:27 -0600, DanG wrote:

It would sure be interesting to see YOU accomplish floor flatness
requirements or install a drop ceiling in a Wal-Mart or similar
competitively without a laser.

LOL I've been doing suspended ceilings for twenty years or so and the
first lasers we used (big things with a spinning beam) were super
expensive- sometimes costing thousands of pounds. Previously we used to
get by using water levels.

A water level can be infinitely more accurate than a badly zeroed laser.

Although nowadays I use a DeWalt DW087K I got brand new from the States a
year or so ago. The best $130 (equivalent GBP amount) I've ever spent (or
should I say 'invested), it's paid for itself many times over in that
time.



--
The month of March in this year of 2009 sees the centenary of the laying
of the keel of the most famous (or infamous) ocean liner of all time, RMS
Titanic, at Harland & Wolff shipyard in Belfast.
http://en.wikipedia.org/wiki/RMS_Titanic

Pete C. wrote:
....

The specs are related to the quality of the bubble levels used in the
units, the quality of the factory alignment of the mirror or laser
mount, etc., not the laser beam itself. The laser beam will spread a bit
with distance, giving a larger spot size because the beams from laser
diodes aren't as well collimated as those from other types of lasers.

Precisely--the accuracy is in making the mounting precise and the
ability to level the unit itself accurately. The cost is in the
machining and other manufacturing to get precision and accuracy there.
The whole device relies upon base leveling and that essentially boils
down to the equivalent of a spirit level--it costs bucks to get the
precision required to translate from +/- some relatively small number
over 100-ft, say, to the equivalent over the few inches at most of the
length of the base. The laser itself is the almost trivial
part--straightline propogation of the light beam comes for virtually
nothing comparatively.

--

On Mar 5, 8:42*pm, Red Green wrote:
So many times I could have used one. Everyday light duty B&D drill has
one built in. It can and has been handy. But I'd like to get a decent
one. Trouble is, even the ones that push say $75 (I know they can cost
hundreds) have an accuracy spec I think sucks for a laser. If I recall,
lasers are coherent light and are pretty darn straight. Light travels
straight unless it's bent or distorted and laser light doesn't disburse
in general. Also if I recall, the intensity and directness of laser light
depends a lot on the mirrors generating the exit beam.

How the hell did I get off on that tangent...?

Anyway, I see accuracy of +/- like 1/2" in 100'. Saw a $35 Sears brand
one today (not self leveling) that was +/- 1/2" in 30 ft. Crimus!, I can
almost do better than that eyeballing.

What exactly is the "accuracy" spec?

For a self leveling one, does this mean the two endpoints at the spec
distance and be off up or down by 1/2"?

How about one that is not self leveling...basically shooting a straight
line. Does it mean the beam can be bowed +/- 1/2" at any point alone the
line?

My favorite is a PLS5 by Pacific Laser Systems. Used it to frame in a
4 over 12 roof replacing a 1 " in 20' shed roof that leaked badly. The
self leveling is great, makes set up quick and easy. Before that it
was a Harbor Freight $30 kit on a tripod, and even that was good for
getting the wainscot heights perfect in several rooms. Checked the
PLS5 once with a plastic tubing and water level rig and it was dead
on. Some the spec variations are due to the spot size, but its easy to
mark the center of the spot for good accuracy. For working outdoors
more elaborate setups with laser detectors are essential. Watch a
survey crew next time you are near one...they have the most
sophisticated gear of all. Even old fashioned farm drainage
contractors and excavating outfits would never go back to older
methods.

Joe

Joe

On Mar 5, 11:33*pm, ransley wrote:

If you need a Laser level, retire or get glasses. That crap is a
gimmic for the gulible.

They work great, if you're not too stupid to use them.
-----

- gpsman

ransley wrote in
:

On Mar 5, 8:42*pm, Red Green wrote:
So many times I could have used one. Everyday light duty B&D drill
has one built in. It can and has been handy. But I'd like to get a
decent one. Trouble is, even the ones that push say $75 (I know they
can cost hundreds) have an accuracy spec I think sucks for a laser.
If I recall, lasers are coherent light and are pretty darn straight.
Light travels straight unless it's bent or distorted and laser light
doesn't disburse in general. Also if I recall, the intensity and
directness of laser light depends a lot on the mirrors generating the
exit beam.

How the hell did I get off on that tangent...?

Anyway, I see accuracy of +/- like 1/2" in 100'. Saw a $35 Sears
brand one today (not self leveling) that was +/- 1/2" in 30 ft.
Crimus!, I can almost do better than that eyeballing.

What exactly is the "accuracy" spec?

For a self leveling one, does this mean the two endpoints at the spec
distance and be off up or down by 1/2"?

How about one that is not self leveling...basically shooting a
straight line. Does it mean the beam can be bowed +/- 1/2" at any
point alone the line?

If you need a Laser level, retire

Done at age 48

or get glasses.

Done that one too.

That crap is a
gimmic for the gulible.

gpsman wrote in news:ecc2a8cc-8ede-45e3-8756-
:

On Mar 5, 11:33*pm, ransley wrote:

If you need a Laser level, retire or get glasses. That crap is a
gimmic for the gulible.

They work great, if you're not too stupid to use them.
-----

- gpsman

LOL! snicker