Red dot laser alignment

[Pete Cyr]

Post by Dean Munt » Mon May 22, 2017 10:14 am
Hoping someone has tried this. Can a red dot pointer be mounted in the lens tube and bounced backwards thru the mirrors to help get them close?
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Post by Pete Cyr » Mon May 22, 2017 11:10 am

You could but I would not view that as practical.
In one of Russ Saddlers early videos he mounted a laser on the glass tube outlet aperture to align mirrors.
It would be best to start at the source to of the beam and align to the laser head vice the way you cited.
Starting with a level and secure glass tube is prudent given the latitude engineered into most assemblies that hold the glass tube. There are typically more adjustment for mirrors than the mount for the tube.
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Post by fred ungewitter » Mon May 22, 2017 2:53 pm
I hope I've contributed a bit to the laser alignment process in the manner described. The thread can be found here:
http://rdworkslab.com/viewtopic.php?f=17&t=1030
There appears to be some controversy, but as I've noted before, I would not have been able to identify the damaged mirror mount without performing this "backwards" laser dot. At the very least, it reduced the time necessary to perform the forward alignment by many minutes.
Despite the success of backwards red dot alignment, it is still very important to perform the normal forward alignment as well.
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Post by Pete Cyr » Mon May 22, 2017 3:59 pm
fred ungewitter wrote: ↑
Mon May 22, 2017 2:53 pm
" There appears to be some controversy"
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Not really - I think what ever works best for each is the best way.
You can certainly work from the laser head toward the laser tube but you will likely a struggle a bit to align the tube to the orientation of the mirrors because the systems are not setup to support. If the tube is properly aligned and only a mirror or two is out it would be easy work.
Without regard how it is performed the ultimate test is how the system actually engraves or cuts.

There is usually more than one way to achieve engineering, different paths have different advantages. Fast and easy may suit some days but if there is risk, depending on the risk that may not always be the desirable path. Slow and hard may eliminate risk or significantly reduce the risk to a real or perceived level and that may be the appropriate path some days. Or it may be a mix of both - each much choose what is right for them - I am pretty risk adverse. In the case of laser alignment... my perceived risk is lost time (and I am lazy - I only want to do it once) so I default in most instances to a tried and proven process.