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View Full Version : Fiber Galvo System or a Fiber Gantry System?



Mark Langston
01-18-2016, 9:06 AM
My company is currently looking at getting a fiber Galvo laser so that we can mark steel and aluminum parts to a specific depth for color-fill or for just leaving engraved into.

The steel and aluminum parts would hardly ever be the same that we would be marking on to, and we would NOT mark hundreds of the same part over and over. We are dealing very much with custom shapes and quantities of less than 60 for each job.

Should we purchase a fiber Galvo system or a fiber Gantry system?

Thanks.

Gary Hair
01-18-2016, 10:05 AM
Galvo without a doubt. Galvo is so much faster than gantry, steering the beam vs flying optics is the reason why it's faster. You'll also find that the ability to "paint" the image to be layered onto the substrate is invaluable, no way to do that with gantry. Plus, galvo gives a much better mark on anodized aluminum, if that is what you are doing. If you need deep marking then I'd recommend a minimum of 30 watts, 50 would be better.

Dan Hintz
01-18-2016, 12:46 PM
How big are the items and what level of detail do you need?

A typical galvo will have a relatively small working field (say, 8" square). You can go larger, but detail level (and power density) drops off as you do. If the item is large, you'll likely want a gantry system... at the cost of severely reduced processing speed. There are combo machines that offer the advantages of both, but they can be finicky for fine detail when matching up the sections, and price increases quite a bit.

Mark Langston
01-18-2016, 1:33 PM
Items could be as big as 39" X 24" and require a 1" character height all the way to 4" X 1" and require 0.250" letter height. The parts vary in size greatly, but no character height over 1" would be used. I don't think I would be doing any letter height less than 0.125".

Ross Moshinsky
01-18-2016, 1:44 PM
I assume chemical etching is a non-starter?

Mark Langston
01-18-2016, 1:55 PM
I assume chemical etching is a non-starter?

We've done chemical etching in the past, but the company is moving away from that.

Scott Shepherd
01-18-2016, 2:26 PM
That large of an area, I don't think Galvo would come close to working for you.

Scott Challoner
01-18-2016, 3:03 PM
Items could be as big as 39" X 24" and require a 1" character height all the way to 4" X 1" and require 0.250" letter height. The parts vary in size greatly, but no character height over 1" would be used. I don't think I would be doing any letter height less than 0.125".
That's the part size but what's the size of the area to be engraved? That's another nice thing about galvos in that everything is open (wear glasses!) so large items don't necessarily matter. I do panels that are roughly 17" x 72" but I'm only marking a 70mm scale on a small area. I have two lenses a 150mm and a 250mm. If it's text that is much larger than that, you have to run in multiple setups. As Gary said, this is made easier by using the red laser to paint a picture of where you are going to engrave so you can line it up reasonably well if it's just text. I do some scales over 300mm so I just end up using the CO2 because I don't think I can accurately line it up.

Kev Williams
01-19-2016, 12:01 AM
I've made my living engraving large pieces of aluminum for years- with cutter tools... And I'd just about bet my rotary machines will engrave anything beyond .002" deep in pretty much any aluminum a whole lot faster than any $30k or less laser... especially when talking 1/8" letters or larger...

Hey, I love lasers, but sometimes old school is the better choice. Just my opinion... ;)

Dave Sheldrake
01-19-2016, 3:01 AM
You can get moving bed Glavo's (One of mine was) start thinking good sized house money though, the head is fixed and runs 400 x 400mm with a moving bed that repositions the job

If its just lettering to be honest I'm with Kev, go mechanical, you could buy 20 3m x 2m routers for what a moving bed Galvo would cost

matthew knott
01-19-2016, 5:24 PM
If you want to fill with paint a conventional engraver is going to be much better, you will always get a burr that makes painting painful, plus it takes ages . Unless you have specific requirements that force you down the laser route then I would avoid, deep engraving takes time on a laser, we have 70 watt pulsed SPI fibre lasers and still it takes lots of time to get in deep ! That's not to say they aren't fun, had a big play the other day as I need a video for our new website, bit of time lapse cheating going on but gives you and idea of what a galvo machine is all about, speed http://youtu.be/7dDvAJ78AL0

tommy suriady
01-20-2016, 8:40 AM
Takes about a couple of hours to mark 0.3mm deep on stainless. abit faster on brass and i think infinitely long on aluminium with a 20w fiber laser on galvo head. You cant mark deep at all with a gantry head. you will get blobs of metal on your surface. I dont think laser is good for deep marking on metal. In fact, laser marked metals are often raised. It will take forever to deep mark the size you require.

get a cutting head on gantry. cut the metal and layer them patiently on a plain sheet. then it will look like it is deep marked.

Dave Sheldrake
01-20-2016, 3:50 PM
I dont think laser is good for deep marking on metal.

bye <click>

Gary Hair
01-20-2016, 4:51 PM
zacly

I have to type 10 characters at least so my zacly reply wasn't quite enough...


bye <click>

tommy suriady
01-22-2016, 1:14 AM
Sorry. Let me correct...
Laser marking is excellent for deep marking very detailed and very high quality deep marking.
But it is very very very very slow.
=)


bye <click>

matthew knott
01-22-2016, 10:00 AM
I knew what you meant Tommy, I'm sure the others did too, so I'm a bit perplexed by their comments. Weird

Mark Langston
02-09-2016, 9:40 AM
That's the part size but what's the size of the area to be engraved? That's another nice thing about galvos in that everything is open (wear glasses!) so large items don't necessarily matter. I do panels that are roughly 17" x 72" but I'm only marking a 70mm scale on a small area. I have two lenses a 150mm and a 250mm. If it's text that is much larger than that, you have to run in multiple setups. As Gary said, this is made easier by using the red laser to paint a picture of where you are going to engrave so you can line it up reasonably well if it's just text. I do some scales over 300mm so I just end up using the CO2 because I don't think I can accurately line it up.

I think my largest engraving area would be 4" long.

Mark Langston
02-09-2016, 9:49 AM
Takes about a couple of hours to mark 0.3mm deep on stainless. abit faster on brass and i think infinitely long on aluminium with a 20w fiber laser on galvo head. You cant mark deep at all with a gantry head. you will get blobs of metal on your surface. I dont think laser is good for deep marking on metal. In fact, laser marked metals are often raised. It will take forever to deep mark the size you require.

get a cutting head on gantry. cut the metal and layer them patiently on a plain sheet. then it will look like it is deep marked.

Thank you!

Mark Langston
02-09-2016, 9:52 AM
Thank all of you who replied. This input is helping me a lot!