DT30 riser plate.

[TechJunkie]

I'm leaning towards DT30s. I see people use a riser plate to lift the galvos to the height of some popular laser modules.

I'm using non standard modules and I dont know if I'll need a riser or not. Can I use the mirror mounts to adjust the height of the beam path instead of using a riser? Or do I have to shim the modules to get to the right height of the galvos? How important is beam level?

Thanks in advance.

[Bradfo69]

I think you can compensate for that a little with mirror mounts. I think perhaps it was one of planters videos that I recall seeing something about that recently. Too much and I think it may be more of a problem.

Level is still ideal though.

[TechJunkie]

Thanks Brad, I'll look up his channel.

[swamidog]

the more perpendicular the beam entry is to the galvo mirrors, the better it will fit on your scanners. you can compensate for small height variations with a bounce mirror before the glavos, but it's best to use riser blocks/shims to correct as closely as you can and then use the mirror for small correction.

I'm leaning towards DT30s. I see people use a riser plate to lift the galvos to the height of some popular laser modules.

I'm using non standard modules and I dont know if I'll need a riser or not. Can I use the mirror mounts to adjust the height of the beam path instead of using a riser? Or do I have to shim the modules to get to the right height of the galvos? How important is beam level?

Thanks in advance.

[TechJunkie]

Gotcha, thanks Dog.

[norty303]

Actually I don't agree with Swami.

Note that Swami says perpendicular to the scanner, not the scanner block. So this means that the lower the entry scanner mirror is compared to the beam entry source the better. Adding shims/risers will only make this situation worse. So in most cases (beam hitting the lower mirror first), mounting the galvo block to the baseplate directly and bringing the beam down into it is the best option.

Also, shims are a pain for very fine alignment if that is how you want to deal with your alignment. Much better to use steering mirrors to put the beam where you want it (imho)

[TechJunkie]

So I understand this. The beam path should angle down onto the bottom mirror first?

If so do you have a degree measurement, or should it be just slightly off level?

[swamidog]

norty,

the comment about adding shims/risers was not exclusive to the scanner block. the idea is to do the gross beam height adjustment be either raising the scanner block *or* the laser sources.

ideally the beam that hits the first galvo mirror would be centered on the mirror and parallel in height to the base plate. unfortunately, there's not enough standardization between the galvo makers, and the laser module makers. having a bounce mirror before the galvos allows you to perform small horizontal and vertical corrections before the beam hits the galvo mirrors.

Actually I don't agree with Swami.

Note that Swami says perpendicular to the scanner, not the scanner block. So this means that the lower the entry scanner mirror is compared to the beam entry source the better. Adding shims/risers will only make this situation worse. So in most cases (beam hitting the lower mirror first), mounting the galvo block to the baseplate directly and bringing the beam down into it is the best option.

Also, shims are a pain for very fine alignment if that is how you want to deal with your alignment. Much better to use steering mirrors to put the beam where you want it (imho)

[norty303]

As Swami says, the closer to perpendicular the better as far as mirror spill is concerned. But 45 degrees is probably not realistic.
TBH there is no 'should' or indeed best case in this scenario, particularly if you aren't totally filling your scanner mirrors.

I was simply making the point that given that its considered best to come down into the bottom mirror from above, and most modules have an exit ~20-29mm high already, to go to the trouble of shimming the block seems pointless (to me anyway). The only real reason for raising the block is to align it correctly with the exit window, but even then, how often to do you need to scan down at any radical angle?

But then, having been through 3 builds of trying to shim modules and scanner blocks, I'm now firmly committed to using steering mirrors, and haven't looked back at the poor suckers doing it the hard way

I've now worked out a way of being able to bolt all modules and scanners directly to the base plate (regrdless of their respective beam heights) and still retain total adjustability using 5 dichro/mirror mounts (previously I used 6). You'll see all that in my new builds in a month or so.

[norty303]

Sorry, crossover in typing....

ideally the beam that hits the first galvo mirror would be centered on the mirror and parallel in height to the base plate.

Why is parallel to the baseplate ideal? This seems contradictory to your previous advice but maybe I'm misinterpreting what you wrote regarding beam entry angle and maximizing space on the mirror for wider angles.