Fiber Laser

[Bruce Boone]

It looks like a 50 watt fiber laser might be in my future.

I had been looking for the past few years for a laser that can both cut and engrave my titanium rings. I finally found a laser that could do such a thing in a Rofin YAG laser. As I expected, it was expensive, like over 200K. It used an air assist to cut just like a CO2 laser that cuts metal. It would have a traveling head and rotary axis to do the ring work. The down side is that the rotary head would be extremely slow on engraved things because of the super fine beam. It was more optimized to cut, not engrave. The laser was large and imposing looking with its own cabinetry and stuff. It was the real deal.

Another avenue I had been checking into was a marking laser. There are setups that are made just for rings that are compact and utilize a fiber laser to do the marking. They use a galvo head and have a super fine beam of around .001" They are easy and intuitive to use. They were OK, but ideally, I wanted to do deeper engraving than the standard models could do. I recently found that Rofin can attach a 50 watt fiber laser to that system instead of the usual 20 watt. I saw some examples of what a 50 watt laser can do to the rings and I'm convinced that this is the way to go. It can do about 90% of what I had in mind at about half the cost. The stuff that would sell would likely be more of the deep engraved stuff rather than the cut through rings like the ones that are mass produced by the Chinese at low prices. The detail possible is really quite something. I have to imagine that multiple passes are possible should I need to get deeper than what's possible in a single cut.

I'll be hashing out details in the month to come, but I'm hugely relieved to have finally decided on the path to go.

[Dan Hintz]

I'm quite envious, Bruce. I've debated something like this but couldn't justify the extreme cost (at least not yet). I'm very interested in what kind of depth/speed you can get with 50W.

[Bruce Boone]

Here's an example of a ring done with a 50 watt laser. Depth might be around .010". Something similar from the laser guy I talked to took around 4 minutes or so. 181894

[Dan Hintz]

What is that, about 10mil average depth? So a 30W would take at least twice the time... sounds like a reasonable trade-off if the price difference is significant. Load up a few rings on the rotary and start working on the next batch. They'd all be done way before you had the next ring ready.

I suppose the downside is that would be an expensive way to go on precious metals compared to casting as you can't recapture what's blown away.

[Bruce Boone]

Here's an example of a laser cut ring. The edges are a bit raw and probably always will be. I did hear of a new type of laser called a disc laser, where intense LED light is directed at a thin disc of lasing material that's directly attached to a heat sink. A wafer just microns thick can give power over a thousand watts, and the beam quality is better! The laser does several layers and ablates the whole time rather than using an assist gas. I don't know what one of those might cost but I figure if I have to ask...
181933

[Tony Lenkic]

Bruce here is another fiber laser mfg. that you may want to talk to:
www dot jimani-inc dot com

[Bruce Boone]

In my application, I would need the speed and the power. We can actually make the rings quite a bit faster than the laser can engrave them. The lathe is a monster. The trick will be to market to large groups such as a high school band or similar organizations where big batches can be made. We just did a batch of class rings for a college in NY and they were machined. They took several times as long as lasered ones would have when the cleanup and finishing was added in. The batch took a week. I also want more power to be able to get effects that others with low power lasers might not be able to achieve. I don't know that a lower power laser could get the look of the ring above. The large pits in the hatched out sections are a result of the power. I still don't know if the laser control can handle multiple passes. While I think it likely can, I don't yet know that for sure.

[Bruce Boone]

Thanks Tony. I did stumble upon them a while back. They also look like they could do a custom setup for what I'm looking for. I was a bit scared at what a one-off pricetag might be. It won't hurt to ask.

I wouldn't mind bumping up to a 100 watt unit if I thought it would work OK, but the experts seem to think there will be problems with the galvo mirror or reflections messing up the laser itself when the power gets too high. That's where the air assist blasting through a conical nozzle usually comes in.

[Bruce Boone]

The plot thickens. I found a company that makes the lasers for the above ring company. They also have an 80 watt laser as well as the 50 watt version that made that. It's a YAG laser, not a fiber laser. I got a part in that was done with it and the kerf actually measured .001" by comparing a gap in calipers and the line under a loupe. Holy smokes that's fine! It looks like a spider web. I'm thinking more power would be the way to go simply for the exclusion factor. The beam spot size is the same between the two models. It would be able to make stuff and cut through a fairly thick ring that other ones can't easily do. Speed is 5000mm per second! That's 16 feet per second! They are made in Italy, so it's a bit scary, but they show the factory on YouTube, and it looks pretty darned advanced. They look to be pretty big in Europe, but pretty new to the US. Very tough decision because the stakes are so high.

[Dan Hintz]

Bruce,

YAG / fiber are essentially talking about the same thing... YAG is the lasing medium (Yttrium Aluminium Garnet), whereas fiber is the delivery mechanism. CO2 wavelengths are roughly 10 times as long as YAG, and fiber is not conducive to transmission at those long wavelengths (hence why you don't see a fiber CO2 machine). Along those same lines, the shorter wavelength of YAG means the spot size will be roughly 1/10 the size of that for a CO2 cartridge. Combine that small spot size with the affinity for metals to absorb the YAG wavelength and you have a very high power density.

If you don't mind sharing (via PM, if you prefer), I'd be interested to know what company you're looking at. And if you have questions about those machines (versus CO2, for example) that you don't feel are getting answered by the big boys, feel free to ask...

[Bruce Boone]

The one I found is Sisma. The model is Smark 500 or 800 for 50 watt or 80 watt. (The Europeans need help with their marketing.) I got in the quotes yesterday, but they mention shipping is Ex-Works whatever that is and doesn't include VAT and I'm responsible for insurance and packing. Who knows what all that might add. I need to get that nailed down before I can move on it. On my Rofin, I ordered it like it was an item from a Stuller tool catalog and it showed up 3 days later. This would be 6 weeks out with all that added to the already hefty pricetag. I'm starting to wonder if it's the thing to do or not. The one thing that is going for it is that I know it can do what I need since I've seen it with my own eyes. The 80 watt should only push those capabilities further.

I was thinking it was more the thin fiber causing the power density of the fiber lasers rather than the wavelength, so that might open up more possibilities than I thought were out there. I've seen plenty of industrial engravers out there that use the YAG setup, but you rarely see them doing serious ablating or cutting. They're made to do lots of parts quickly. I imagine the galvo mirror might be the critical component. Maybe it can't stand more than a certain threshold of power, or maybe there's just little demand for the kind of laser I'm looking for. This one is diode pumped, so it should do better than a typical flash lamp for running life.

[Richard Rumancik]

Bruce, it would probably be best to talk to a broker who can advise you on the importation issues. I think Ex-works basically means that you own the laser at their shipping dock, so if it falls off the dock when loading then it is yours, not theirs. So that means you need insurance from the point of departure. You may be able to get a rider on your business insurance to cover this. As far as the VAT is concerned, there are some exemptions to companies outside the EU so again the broker will be able to advise you as to whether you pay this or not, or if you can recover it somehow.

[Dan Hintz]

The fiber itself is doped to provide a wavelength shift (doubling, tripling, etc.) of the source diode. Lamp life is measured in a couple of thousand hours, whereas a properly rigged diode is measured in the 10k hours range... significantly better, but once the diode is dead, it's dead. A dead lamp can be replaced. Something to consider.

Along with Richard's comments, make sure you can get FDA approval on the incoming set if Sisma does not already have a certificate... that'll stop the unit in customs for an eternity (literally, if you can't get approval).

[Joe De Medeiros]

FDA approval on the incoming set if Sisma does not already have a certificate... that'll stop the unit in customs for an eternity (literally, if you can't get approval).

Why does it need FDA approval ?, is this similar to CSA approval in Canada ?

[Bruce Boone]

I had another chat with the sales person this morning. I got a revised quote that will just be FOB Connecticut. Maybe around $500 or $600. No VAT or Ex-Works stuff to worry about. Now the cost is the actual cost, so I won't have to lose sleep on that part of it. Price was tweaked to below 6 digits. Also typical turnaround time is 30 days, not the 6 weeks that they list. It's definitely sounding a lot better than it did at about midnight last night.

The machine is CE certified, which is the UL type thing in Europe.

[Bruce Boone]

Well, it's a done deal. I ordered it today. :eek: :)

[Dan Hintz]

Why does it need FDA approval ?, is this similar to CSA approval in Canada ?
The FDA (I know, why would the Food and Drug Administration care about lasers) has purview over radiation-emitting (lasers included) items being imported. It's generally not a problem, but all it takes is one item to be declared incorrectly on the paperwork and the FDA has it held in customs.

[Dan Hintz]

Bruce,

Was that price for the 50W or 80W unit?

[Bruce Boone]

I got the 80 watt with a rotary axis and vacuum system. Their site shows a sherrif's badge cut from about .090" steel with one. It looks to have the power to both cut and deep engrave. The total with the shipping was just over $100K.

Now I'll have to figure out what to do with my CO2 laser since all of my stuff should be able to be done faster and better. I imagine I'll hang onto it since that was about $26K plus the HDPFO lens when I got it and I can't hope to get anything near that now. I'll just need to find the right application for it.

[Dan Hintz]

Bruce,

Just be aware that the CO2 system is only unnecessary if you plan to stick with metal cutting only. You will not be able to work with organics using the fiber laser, so no plastics, wood, etc.

If you decide to part with that HPDFO setup, I may be interested...

[Bruce Boone]

It will come in handy for doing plastics, like special fixtures and things like that. I found a spot for it behind my machining center in the back corner. It's like I'm sending my child to stand in the corner. The new machine will come with a lot of emotions. I've agonized over the decision for a very long time.

There might be good possibilities with wood inlays in rings. If I can do a deep cut, say in a sunburst shape, deeply engraved into a ring, then do a corresponding wood cutout, it would be a unique look. It would be handy for pens if I ever decided to really get back to those. It's also a huge cabinet, so stuff like canes are possible to do in it. I was at WoodCraft once and the guy that does a weekly laser engraving gig was in doing mainly pens, and there was a guy that wanted a cane custom lasered. The laser guy replied that he didn't know of anyone in the state that could do such a thing. I was standing behind him and said I could do it, so just follow me home. He did, and I lasered some great graphics on this beautiful hand carved cane with a human face and great detail. It was to be a gift for someone special to him. He was so taken with it that when I asked for $50, he gave me $100 and wouldn't accept less.

[Adam Orton]

I always thought FDA was for food stuff. Just tell em "though the laser has a rotary unit which looks like a rotisserie unit I will NOT be cooking any hotdogs in my laser"..

[Dan Hintz]

I always thought FDA was for food stuff.
Here's a snippet:
http://www.fda.gov/radiation-emittingproducts/resourcesforyouradiationemittingproducts/consumers/ucm142607.htm

Essentially, they want verification the system will not be used on humans/animals. In theory it's a simple bit of paperwork... in reality, it can be a huge furball, depending upon who you run into.

[Jon Colley]

Dan is 100% correct on this point. The CDRH division of the FDA sets the rules for lasers in the US they require that any system being imported into the US must comply with their performance standards. You will need to provide an FDA-2877 form to clear the shipment into the US otherwise it will sit in bond. If that model has been FDA approved, they should be able to give you an accession number that goes on this form and then importing it shuold be no problem.

[Bruce Boone]

I'm sure they will do that. It's a class 1 laser, so it has a full enclosure with safety interlocks. We made the first half of the payment today, so it should arrive in a month or so. I can't wait.

[Dan Hintz]

Bruce,

Just so you're aware, that is a Class 4 system (revised classification system), not a Class 1.

[Bruce Boone]

I must have not heard of the new classifications. I thought a class 4 was one in the open that could cut you up and you need glasses and stuff. Used on mold and die work and stuff. The class 1 was safe for factories with no extra protection. That's what their information says anyway.

[Dan Hintz]

They may be classifying the entire workflow/system. Classifying the laser itself, a Class 1 laser is inherently safe no matter what (i.e., very low power). Even the next step down from Class 4, the Class 3B, is limited to 0.5W at the CO2/fiber wavelength, and even then it must include a safety interlock system. I suppose if they are classifying the system as a whole (and it really shouldn't be classified this way), as long as all interlocks are working, the system as a whole is inherently safe (at least from a radiation standpoint).