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gundog
05-24-2008, 06:37 PM
I am thinking of putting laser alignment on some of my home shop machines. I spotted this on ebay.

http://cgi.ebay.com/650nm-5mW-Red-laser-LINE-module-3VDC-Same-Day-Ships_W0QQitemZ160242978488QQihZ006QQcategoryZ5314 1QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Can someone explain the 650NM is that the size of the laser line? Does that mean 650 nano meter is that real small? I would like to put one of these on my CNC router table and my hydraulic press. I just don't know how wide the line will be. The further the laser gets from the surface does the line increase in size I would think it would? I have heard the arguements about accuracy with line width. As my eyes get worse with age I can just see this being easier for me. I was thinking about one for the horizontal bandsaw also. For the price I could just see adding them too a couple tools around the shop.
Thanks Mike

gundog
05-24-2008, 06:47 PM
I found part of the answer.

650 Nanometers = 0.00002559055118110236 Inches

NickH
05-24-2008, 06:58 PM
It's the wavelength of the laser light emitted,
Nick

rantbot
05-24-2008, 07:33 PM
It's the wavelength of the laser light emitted,
Right, it just means that the light is red. The visible spectrum runs from 380 nanometers (violet) to 750 nanometers (red).

Bruce Griffing
05-24-2008, 08:23 PM
Be aware that lasers have beam divergence - the beam spreads out as you get farther from the laser. Also, cheap lasers are poor at what is called "pointing accuracy" - the beam wanders around slightly in direction. This is only a problem is you expect very accurate readings. Cheap lasers are fine for woodworking, but you either need to use special techniques or better lasers for metalworking.

Evan
05-24-2008, 08:57 PM
Potentially a laser alignment system can easily beat any other type of system hands down. In practice it is a lot harder to realize the full potential of a laser measuring system. To start with the laser light itself is hard for the human eye to focus on well as it causes diffraction patterns within the eye. It's nothing harmful, it just makes it hard to actually see the central spot of light or to focus on a laser line. Laser light also interferes with itself because of it's coherent and monochromatic nature. When it strikes a surface it causes minute light and dark areas where the light either cancels or reenforces due to slight variations in the surface height and texture. This is what causes the sort of "grainy" look that a laser spot has.

gundog
05-25-2008, 12:01 AM
How much would I need to spend on a better laser for reaching a distance of about 12" or less? I am looking for around .005" accuracy. I want to cast a beam not just a dot. My CNC router has a Z travel of 6". I bought a laser edge finder and it is real handy but it mounts in the collet and it requires removing the bit. Mounting some beam type lasers on the machine would make for faster setups. Where would I look for better lasers?
Thanks Mike

Dawai
05-25-2008, 01:34 AM
With .005 as a resolution, you can start at Sears....

Look on my mill.. now about four years old?? I forget..
http://www.youtube.com/watch?v=Ifhmh6-fMKw
.
Sears lasertrac?? was $39... now??? THE one for the drill press has two lasers, two waffle type diffuser lens.. runs off two AA batteries.. or in my case off a USB cable on the pc..
I had to dissasemble mine, redo it with epoxy paste on a piece of aluminum that the quill would fit through.

David

crancshafter
05-25-2008, 05:37 AM
I am thinking of putting laser alignment on some of my home shop machines. I spotted this on ebay.

http://cgi.ebay.com/650nm-5mW-Red-laser-LINE-module-3VDC-Same-Day-Ships_W0QQitemZ160242978488QQihZ006QQcategoryZ5314 1QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Can someone explain the 650NM is that the size of the laser line? Does that mean 650 nano meter is that real small? I would like to put one of these on my CNC router table and my hydraulic press. I just don't know how wide the line will be. The further the laser gets from the surface does the line increase in size I would think it would? I have heard the arguements about accuracy with line width. As my eyes get worse with age I can just see this being easier for me. I was thinking about one for the horizontal bandsaw also. For the price I could just see adding them too a couple tools around the shop.
Thanks Mike

Mike
Get one of this;) :http://www.dealextreme.com/details.dx/sku.5942

Swarf&Sparks
05-25-2008, 06:25 AM
Yeah, Cranc, I'll vouch for that.
I think it was Sir John who pointed em out.
I ordered 3 of the cross-hair lasers and the service was prompt.

I'm now awaiting arrival of a 200mW unit to do some CNC etching :D

Evan
05-25-2008, 08:15 AM
I have a good size order coming in from DealX. No problem with their service, they shipped as advertised but my order is stuck in Canada Customs waiting for somebody to pull their thumb out of their asp. It's been sittiing there for ten days now.

Cross hair laser isn't the best way though. On a mill use two line lasers to project a cross (one X and one Y) and it will always be on the centerline of the spindle regardless of the distance to the table.

gundog
05-25-2008, 01:19 PM
The price is right on the dealextreme but I would like one line units rather than the crosshair do they have those I did not see them listed?

crancshafter
05-25-2008, 03:37 PM
The price is right on the dealextreme but I would like one line units rather than the crosshair do they have those I did not see them listed?

gundog.

red line laser no problem, here you go:D
http://www.dealextreme.com/details.dx/sku.5928

gundog
05-25-2008, 04:42 PM
I think I went overboard I ordered 2 crosshair type and 5 straight line type. It will look like a high tech alarm system in the shop. If the tweakers break in they won't know what to think.
Mike

Evan
05-25-2008, 10:36 PM
I just received my order today which includes two of the line laser modules to install on my mill. They look very nice and focus to a very sharp line. I'm also happy with the rest of the order so far although I haven't tested everything yet. Incidentally, it all came through unopened and with no duties or even a handling charge. It will be interesting to see just how powerful the 1/2 watt IR emitters are that I ordered.

Swarf&Sparks
05-26-2008, 12:57 AM
Didn't notice the 0.5W IR Evan. I presume they come with feedback diode?

Evan
05-26-2008, 03:24 AM
No diode. They are just high power LEDs, not lasers. It's to provide light for my security cameras.

macona
05-26-2008, 03:39 AM
On ebay there is a guy selling 3 watt luxeon style IR Leds. Pretty darn bright. The chip glows red but with my camera its blinding. He has 5W IRs now as well.

http://cgi.ebay.com/5-Watt-Infrared-IR-LED-Night-vision-camera-Flashlight_W0QQitemZ350063657536QQihZ022QQcategory Z66954QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

Swarf&Sparks, 200 mw is not going to do much on anything other then black plastic. And then pretty slow.

hwingo
05-26-2008, 07:56 AM
I purchased a Laser/Center Edge Finder from SDA in Piedra, Ca.

www.lasercenteredgefinder.com

(559) 787-2580

Beam size of dot is adjustable and I've found this small instrument to be very useful. The housing has a 1/4" shank that can mounted in either a mill collet or the head stock of a lathe. Not only is the beam size adjustable (using polarizing filter that's attached to the unit) but if the beam becomes off center, this too can be adjusted. The beam can be adjusted to *pin-point* size and the maximum size of beam is about 3/4mm.

The line laser I purchased is not impressive. It works but the line is too wide for my application .... even using a polarizing filter does not significantly reduce width of line. The line is about as wide as the one shown on ebay (1 to 1.5mm) which in my opinion is too wide.

Harold