Any one using&experienced Galvo Lasers ?

[onur cakir]

Hi Everyone !

For seconde time i get an order which is about 70 m² !

Here's the deal :

I want to use 20 cm x 20 cm glass tiles, it takes 17 min. to engrave 1 pcs and 25 pcs per 1 m² needed.

25 x 70 = 1750 pcs
1750 x 17 = 29750 min / 495 hr !!!

That cost too high for my client !

So my plan is to use a galvo laser which finishes my 17 min. job in 2 min !!

Any help with galvos will be welcomed

Thanks !

[Mike Null]

Onur

I believe Synrad will give you some advice. http://www.synrad.com/index.html

[Bruce Volden]

Onur,

Funny thing, I was just looking at this system yesterday. Seems like it may be what you're looking for.

http://www.lasertile.com/lasersystems.html



Bruce

[Dave Johnson29]

For seconde time i get an order which is about 70 m² !


Hi Onur,

Galvos are fast but the problem is swept area. The largest swept area I have seen was about 10" with a really usable area closer to 7". The outer regions (corners) were starting to get quite fuzzy and the really usuable section was about 7" diameter.

With a galvo, the larger the swept area, the larger the dot size as the swept area is increased by increasing the length of focus and distance from the focusing lens.

A rule of thumb is that as swept area goes up so too does the power requirement for the laser if you are makring stuff like glass and ceramic that requires a lot of power. Marking wood is not so power dependant.

Bear in mind that a galvo is not good for cutting as the beam eminates from a single point so the kerf angle increases with the distance from the center.

As Mike suggests, a good place to start is with Synrad and keep that check book handy. :)

[Gary Hair]

Onur,
20cm is only 7.875" so those are roughly 8" tiles. If the galvo laser has a usable area of just over 7" then it may work. I would send a couple of tiles to the manufacturer and have them show you if it works. Another option would be to buy a larger CO2 laser. I could fit 8 of those at a time in my laser, maybe 10 depending on the image. I guarantee you that it won't take 8 or 10 times as long to do 8 or 10 as it does to do 1. If you bought a higher power laser as well then you could certainly increase the speed. Finally, if you had a large bed, 120 watt, dual head laser, you could probably get the time down to a fraction of what it is now.

Just some thoughts...

Gary

[David Romano]

Hi Onur,


Bear in mind that a galvo is not good for cutting as the beam eminates from a single point so the kerf angle increases with the distance from the center.

As Mike suggests, a good place to start is with Synrad and keep that check book handy. :)

I don't own a laser engraver, but having a background in laser micro-machining, I can tell you that the laser does not exit from a single point in a galvo system. If this were the case, the image plane would be curved, or the spot would be out of focus. A galvo lens is an F-Theta lens, a "flat field" lens which keeps the spot in focus over the scanning area. The angle that the beam hits the media should not change much. There is a calibration procedure to correct for errors in placement, but focus is handled by alignment only.

David

[Dave Johnson29]

I can tell you that the laser does not exit from a single point in a galvo system.


David,

I was over simplifying the process with that explanation but the point still remains valid. The farther out on the swept area the greater the angle of the finish cut for say 1/8" acrylic. It will never be vertical across the entire swept area.

Not that Onur is asking about cutting, I just tossed that comment in as a precautionary note.

[onur cakir]

Thanks for replys,

Here is what i experienced with galvo :)

The machine is made in Turkey by a member of this forum also. He's a pro at his job with lots of experience. Swept area is 30 cm / 12" with 100w synrad tube. If you plan to do engraving only it can work up to 40 cm with no problem.

It finished my 17 min. job in 2 min. per pcs with galvo !

Print driver is a big issue for galvo systems because only 3Score has a proper direct CTRL+P driver for galvo. For other galvo systems you have to divide patterns into lines. Like we adjust DPI or PPI, you set your image like 5 lines per 1 mm. or 10 lines per 1 mm. etc.

Second issue was frosted results on glass. My usual settings for glass with 45W Epilog is 600 DPI S100 P100. I get a smooth, clean and lightly frosted result ideal for re-painting process. With galvo we had deeply frosted result. As we tried to lower the power we had trouble with engraving and some paint left on glass.

Optimizing power & speed is hard on galvo. You need to find setting for fastest and cleanest result.

Buying a servo laser with larger bed&double head is an option too but i have to survive for 3 more years for that.

I'll check synrad for settings.

[Rodne Gold]

For the price of 1 x 100w Galvo , you can most likely buy 3-5x 25w smaller "normal" machines and do the job in the same time and end up with some serious capacity for other jobs.
I'm not quite sure of your logic with this job , you gonna buy a $50 000 machine or a much more expensive one than you have to do "cheaper" work?

[onur cakir]

For the price of 1 x 100w Galvo , you can most likely buy 3-5x 25w smaller "normal" machines and do the job in the same time and end up with some serious capacity for other jobs.
I'm not quite sure of your logic with this job , you gonna buy a $50 000 machine or a much more expensive one than you have to do "cheaper" work?


I'm planning to rent that machine. Easiest thing is to sign a big contract and get a sub-contractor for job :)