Laser alignment tool - IDEAS?

[lucasp]

Hello guys,

I'm new on the forum, and a first search didn't find any threads about this application.

Any ideas on how to verify the alignment on a "home made" roller alignment tool, similar to this commercial product?


My concern is about being sure the laser is "exactly" perpendicular to the base.

Best regards!
Lucas

[LaNeK779]

maybe i don;t read you right, but will one of these bubbly thingies do the trick?

they are small enough to fit on a picture camera's hot shoe (where the flash goes into)

[lucasp]

LaNeK779

Acctually I need to ensure both steel rollers are parallel. To this, the laser must be exactly 90º to the first roller (base). And this is my question (really not so clear...): how can I test this 90º alignment?

[Eidetic]

I'd put it on a roller that was laying on a long optical table and adjust the laser to make its horizontal beam parallel to the table surface using a power meter with a small aperture mounted to its face. Then I'd reflect the beams back to be centered on the laser with a front surface mirror, and use another mirror in contact with the back side of the roller under the laser to adjust the laser horizontally until the reflection off that mirror aligns with the beam on the first mirror. Longer table equals more accuracy.

[laserist]

depending on your definition of exactly:

fairly accurate: If the shaft is horizontal and you rotate the laser/vblock around the shaft the beam will track a plumb line.
or
more accurate: Set two shafts on a surface plate and adjust for parallelism using an auto-collimator and adjust your system...
or
more accurate: place a short section of shaft on a level (precision) indexing table, place the laser/vblock assembly on the shaft and level it, mark the position of the beam at as long a distance as you can, rotate the indexing table 180 degrees & reverse the laser/vblock assembly & re-level the assembly, adjust out half the error, rinse and repeat (you should realize the target point needs to be reestablished each iteration... (If you intend to have line generating optics the target point becomes a line/lines. The vertical line needs to be checked by rotating the laser/vblock assembly around the shaft.) (Indexing table accuracy should not be assumed...)
or
use some other variation on autocollimation...

Hello guys,

I'm new on the forum, and a first search didn't find any threads about this application.

Any ideas on how to verify the alignment on a "home made" roller alignment tool, similar to this commercial product?


My concern is about being sure the laser is "exactly" perpendicular to the base.

Best regards!
Lucas

[lucasp]

I'd put it on a roller that was laying on a long optical table and adjust the laser to make its horizontal beam parallel to the table surface using a power meter with a small aperture mounted to its face. Then I'd reflect the beams back to be centered on the laser with a front surface mirror, and use another mirror in contact with the back side of the roller under the laser to adjust the laser horizontally until the reflection off that mirror aligns with the beam on the first mirror. Longer table equals more accuracy.

depending on your definition of exactly:

fairly accurate: If the shaft is horizontal and you rotate the laser/vblock around the shaft the beam will track a plumb line.
or
more accurate: Set two shafts on a surface plate and adjust for parallelism using an auto-collimator and adjust your system...
or
more accurate: place a short section of shaft on a level (precision) indexing table, place the laser/vblock assembly on the shaft and level it, mark the position of the beam at as long a distance as you can, rotate the indexing table 180 degrees & reverse the laser/vblock assembly & re-level the assembly, adjust out half the error, rinse and repeat (you should realize the target point needs to be reestablished each iteration... (If you intend to have line generating optics the target point becomes a line/lines. The vertical line needs to be checked by rotating the laser/vblock assembly around the shaft.) (Indexing table accuracy should not be assumed...)
or
use some other variation on autocollimation...

Eidetic and laserist, these are great ideas!

As I have no easy access to an autocollimator, I'll start with laserist third idea. I have a lot of space at our building, and it will no be a problem to test on this "iterative" manner.

The final use will be similar to the one at the picture, but with rollers about 20m far. Any thread on the forum about a fine tune mechanism, such as the "gun sight" system? This would be helpfull...