Fiber 300mm lens

Ok, I’m looking to get a fiber laser to basically do 3 things. Engrave powder coated tumb’s, engrave cork or slate coasters, and engrave anodized keychains. I’ve watched several of “Laser Everything” YT vids. Especially this one.

My goal with the tumbs is to speed up my engraving time. I like the idea that I can place a tumbler down between 2 blocks shown at around 8:24 in the vid, and engrave it, then just replace it -vs- the process I have to do now on my CO2.
From what I understand, a 300mm lens should be able to get me to engrave lets say a 3" wide piece of artwork. That’s the general size I’m doing. Sure, I can get a chuck style rotary, but why pay for one, if it’s not actually needed per the vid.

I’m looking at the 30w monport.

Let’s pretend I buy their 300mm lens. I know that will make a larger focal point on my product, but will it give me the capability to engrave 3" artwork across the tumbler, or is that determined by the size of the stand that the galvo is attached to.

Any info would be greatly appreciated.

The focus distance on my 300mm lens is 437mm from the workpiece. My laser is a 60w JPT MOPA.

Just took some measurements on mine based on what you’re trying to do. I have enough room on a 500mm tower to get a 88mm tumbler laying directly on the table with about 25mm to spare in up travel. 100mm tumbler would also work with about 13mm to spare in up travel. I think you’ll be on the edge but it would probably work for you, but, just barely.

I’ve not messed with the technique you’re trying to do though. I do my tumblers with a 200mm lens on the rotary.

ETA that the 300mm lens will do way larger than 3" images. What’s going to limit how large your image can be will be the diameter of your tumbler. Using the method you’re wanting to try, as the image falls further down the dia of the tumbler, it will be further out of focus and you’ll get to a point where it won’t remove the powder coat enough for a clean engraving. You’d just have to experiment with your setup to see what it can do.

That one is a video about the wonders of Panama City, Florida, with no lasers visible to the (goggled) eye.


Too funny Ed. I got that corrected.

Thanks. We just got back from PCB.

Thanks Brian.

I can always get a rotary, if need be. Just want to save the expense of doing so. Your right. I guess I just need to get a fiber, test, and if it works as I want, then great. If not, more stuff to buy… :wink:

From what I understand the fiber lasers are much quicker of removing powder coat than my CO2. Looking to improve processing time. It’s not a full time job, but still would rather spend 30 sec on a tumbler -vs- 6 minutes.

This is what I use for my rotary, and of course at this point in time, not even sure it would be compaitible.

Lol. I wrote all that to basically say “I dont know”. Hope the measurements answered some of your questions though.

Totally understand the process time reduction. My tumblers are 3-6 minutes on the chuck rotary. Its not fast but is what gives the best, cleanest engraving. I find there is always compromise on process time vs quality.

No worries B.

I always appreciate feedback, no matter how much of it is Gibberish Na, Just Kid’n man. Don’t take me serious. I do appreciate the insight.

I can see no reason why your rather lovely ( I’m jealous ) rotary device should not work with a fibre galvo.

My rotary is a 2 phase with an aviator plug, just like your pic shows, and it works like a dream, apart from operator error at times of course.

Have fun, when the fibre arrives :+1:

Hi David.

There is a caveat to my statement about it not possibly working.

Long story short. I have a monport CO2. When I ordered “their” rotary, the first one I ordered, it vibrated on the bed of the laser very violently. Wasn’t sure what the heck was going on. They sent me another one. Besides the wheels being off center, and not level, it still vibrated real, real bad.

I said fine. I found Jason’s. He sent it to me, and low and behold BOOM. The same problem. WTH? Jason worked with me, along with Jack here on the forum. It seems for what ever reason on Gods green earth, my CO2’s aviator plug was wired in the wrong fashion as most.

I finally identified A+, A-, B+, and B- with the gracious patience of Mr. Jack here, along with Jason. I had to re-solder the plug. No Biggy, but I spent hours trying to get to the bottom.

Of course, my current rotary which is a 2 phase rotary, is wired kind of different so I could get it to work with my current CO2.

Even though this isn’t a “real” depending on business operation I have here, I still feel the need for a backup, and/or another laser to take up some slack. Those 300 tumblers kept me in my shed for hours, and hours…

Just the back story on my Rotary adventure with Monport.

Now I just need to talk myself into getting it !

A lens choice with a fiber is a little different…

I bought mine for 300x300mm coverage… It came with and F420mm lens and an almost meter high column, 80cm. You can see the lens markers on the column…

You have to have enough room on the column to raise the galvo head above the work piece… at least enough to focus.

This is from Cloud Ray … the last number of the part number is the focal length, the 2nd to last is the coverage area. Not all part numbers have the coverage.

A G suffix usually indicates use <100W and they are about 1/8th the price of the same lens rated at >=100W. >100W are made from different materials.

There are also different scan angles… an F254mm lens could cover 175x175mm or 160x160mm depending on the scan angle.

Longer lenses have a larger dot size (encircled energy) or focus point with a greater depth of field.

A greater depth of field will allow you stay in focus for a greater range, so focus isn’t as critical, but the shape of the object can induce optical effects. This is pretty evident with flask because of the shape. These are software tools to help correct this…

I’ve had to manually move the Z while engraving deeply into some coins with the F100mm lens because there is little depth of field… shorter lens, smaller dot and more shallow depth of field.

There is a change in parameters when changing lenses, the smaller lens, F100, do will do more damage at the same settings as the F420 because of the dot size.

The worst case with your rotary is that the connections in the Fiber are not the same phase pins as your Monport, in other words they operate the same, but pinout on one machine isn’t the same as the other… Unfortunately, like all of the Chinese machines, there is no standard pinout that I know of.

There is a relatively easy fix, we call it a pigtail where you have male and female connectors abd the wiring swap is done within the pigtail, so you plug it into the pigtail on one machine and directly into the machine for the other…

I haven’t tried the PiBrun on my fiber, but they use the same motor drivers so they should operate the same…

Keep in mind, if you need to use a rotary, it will slow down the process, it can’t move as fast as the mirrors in the galvo head.

Good luck


Thanks Mr. J.

Yeah, I’m pretty clear on Focal Lengths, and how they can effect focus or scans, or I believe I do. Some of that kind of spilled over into my photography.

I really would like to get away from a rotary if “possible” to maximize my time while burning tumb’s. BUT, if I have to, fine. It still has to be quicker with a fiber and rotary than my CO2 and it’s rotary, or that’s what I have in my head.

As always it’s going to come down to cost per se’. You usually get what you pay for. I’ve never even thought of marking metals with. My target as of today, is Tumblers.

Have a great weekend. I’m going to scour the web some more. I actually spoke with someone at the other end of my state that has the one I’m looking at. He uses a rotary as well.


I just received this in from Monport via mail.

If you use 300*300MM lens, that means the width can be 30CM for engraving, so 30W is enough for you to engrave your tumblers.

They didn’t say if I can do it without a rotary though :slight_smile:

I replied back asking that.

If you can relate photographically maybe that will help… I still have and use now and then a 6x7cm medium format and 4x5" large format cameras…

You say you want to engrave a mug … for what you ask it tells us little…

Show us a photo of the mug so we can see the back side… you can’t and your laser is no different… there is only a certain amount of a cylinder or ball shape you can see from the laser if you don’t have a way to rotate the cylinder.

Two things happen, the image gets the stretched look as it goes around the curvature of the mug. The distance changes the focus, which affects the beams ability to damage to the material.

This is some ways to correct for some amount of distortion, but I haven’t done it and someone else would have to advise.

If you are doing 2mm high letters there is no need for a rotary… If you want to go around the mug you’ll need a rotary.

Here is laser everything video on mugs… I think you’ll like it… I believe he uses a 30W fiber.

Make sense?


Hi Jack. Yeah, I can relate focal length through my background in photography in a round about way. I actually had my own darkroom in the back of the studio. I had a Mamiya RB67. I still own my 5x4 for what it’s worth. Oh miss those days in the darkroom, watching it come to life. As they say. We move on.

I’ll watch the vid. I’ve seen several of his, and am really digging into them on fiber.

Thanks for your input as always.

I had the RZ67… :wink:

I always wish I could have been able to afford the digital back for the 4x5 they came out with…

It’s all proprietary systems and expensive… For some reason they are not as convenient to use as a cell phone or other digital camera… :face_with_spiral_eyes:

Go out to SarbarMultimedia and watch some of the Russ Sadler videos on his fiber machine … He’s an engineer and knows metals… He can probably clarify some of these issues.


Yeah, I’ve been watching his too…

BTW, you should see the strange looks I got in Memphis around Beale street shooting 5x4 and the RB.

Good times.