Epilog first impressions


#1

I know a lot of people here are pros with multiple lasers under their belt (hmm, that sounds weird), but the only experience I had prior to owning a Glowforge was a dying Full Spectrum machine at a maker space at work. It took a dozen passes to cut through 1/8" acrylic and shortly after gave up the ghost.

We got a new one, though, an Epilog Mini 24, and last week I spent a very short time trying to help set it up. It was an interesting experience, so I thought I’d share my impressions here. This is by no means a fair comparison or a review or anything like that. Just what I noticed straight out of the box and during our first run attempt. Also worth keeping in mind, I believe this machine costs a fair bit more than the Glowforge. I was not involved in the purchasing, and it’s one of those “call a distributor for a quote” things, but some web searches suggest it goes for something like $19,000. That’s not including the huge BOFA filter which I think alone costs more than my Glowforge.

Anyway. First things first. It’s a boxy box. It’s not an object of art, but it’s not quite as bad as the scrapyard sheet metal look of the Full Spectrum. It has quite a bit of z height. I don’t know the specs, but certainly can handle taller objects than the Glowforge. It has a motorized bed that moves up and down to focus, which seems straightforward compared to the complex focusing in the Glowforge head. Autofocus too, via a mechanical probe that touches the material as the bed raises up. And of course, limit switches to find its zero position. Mechanically, it seems simpler with fewer overengineered parts to break down.

One thing that surprised me was that it’s air cooled. I thought that was fairly unique to the Glowforge, and the thing I hated most of all about our old machine was the bucket of water and aquarium pump it used for cooling. Messy and gross. But this one doesn’t have that problem. I don’t know what the environmental parameters are, so it’ll be interesting to see if it overheats like the Glowforge does. It has quite a few fans on the top. On the topic of fans, I don’t think it has an exhaust fan. I could be wrong, since it’s hooked up to the BOFA, but I think if you want to exhaust it outside, you need to supply your own blower. Finally on the topic of fans, the air assist is also external. It has a small port in the back that you need to supply an air feed to. Ours came with a small air pump to plug in there, not sure if that’s standard equipment. The whole contraption is very loud between the fans on the laser, the air pump, and the air filter.

There’s a small control panel where you can do basic things like turn on and off the red dot, raise and lower the bed, and start and stop jobs. It has the most unusual method of setting a new home position: you toggle an option in the menu to power off the stepper motors, then grab the head and move it to wherever you want. It’s certainly fast, but if the Glowforge is overengineered, this feature goes a bit too far in the opposite direction IMO. Speaking of low tech, how do you preview a job? Turn on the red dot laser via the control panel, then run the machine with the lid open. This prevents the main laser from firing, but it still runs the job. I works, but seems like it should just be a software option to run a preview.

And now we get into the meat of the thing. The software. Oh my god. I thought the software for our Full Spectrum machine was horrible. I had two hours available to help with this machine, and the entire time was spent fighting with their horrible print driver to try to get it to do what we wanted. Literally, I went down to help, we spent a solid two hours on failed attempts to cut something, and then I had to leave. I’m 42 years old, I have spent all my waking hours with computers, I own a laser cutter, and I work as an engineering manager at Google. Another Google engineer and I spent two hours trying to get a piece of software to work and we couldn’t do it. Getting the damned thing working is only the first step. This is in a shared-access maker space, so we need a way for people, with only basic safety training, to be able to walk in and use the machine. I am seriously worried about whether that’s going to be possible. It’s that bad.

With all the complaining about Glowforge’s cloud service and people clamoring for it to be a print driver like every other laser, I was not expecting to have such problems stemming, fundamentally, from it being a print driver. The problem with that approach is that the API for printing on Windows isn’t designed to transport vectors losslessly, it’s designed to get ink onto paper. Printing from Inkscape causes the output to be rasterized. All of our vectors turned into rasters. And the Epilog software makes it very hard to understand what’s going on or control what you’re going to get. The documentation is miserable, and there’s no provision for understanding what’s going wrong. Surprisingly, for such a basic failure mode, searching the web for answers turned up very little, most of which was conflicting or incorrect. It’s clear that you can’t just print from Inkscape, but there’s an extension that’s supposed to work. But printing through that extension just caused the machine to beep and say “Done”. Except for the times it caused gibberish to appear on the display. We tried variations of stroke widths suggested by various web sites, and we tried exporting to PDF and then printing the PDF, from Chrome, from Edge, and from Acrobat Reader. We tried sample files from the manufacturer. We tried creating a plain circle in Inkscape. Somewhere we read that you can’t use circles (what?) so we tried making a square. One of our attempts worked, but we don’t know what we did differently and couldn’t reproduce it on demand. I wish I had written down some of the useless error messages that popped up, when anything was displayed at all. I would take the cloud issues over this any day. Times a thousand.

Finally, having described the biggest downside, I’ve saved the biggest upside for last. The speed. The speed is astounding, for someone used to a Glowforge. I used to be satisfied with my machine, but now I realize how serious of a limitation it is to have that giant head. Take a look at this first search result to get an idea for how fast it goes: https://youtu.be/Q5xLzZbhheo. I’m not saying that’s worth $13,000 more to me, but I do wonder if Glowforge had gone with a more conventional design whether this type of speed would have been within reach.

All in all, it seems like a fine, but overpriced, bit of hardware that is completely hobbled by a software experience straight from hell.

When we get it up and running, if we get it up and running, I plan to do some tests of things I’ve made with my Glowforge and see how the quality and real-world speed compares.


#2

Isn’t the speed directly related to the power of the laser? What is the power on that tube?


#3

Ours is 40w I think. Maybe 50. Close enough to my Pro’s 45.


#4

Cutting speed is going to be cutting speed for the most part when you’re talking comparable wattage and optics. Engrave speed is a different story.


#5

Sounds like a good comparison, plus and minus. (Almost went with an epilog, but that huge honking filter dissuaded me.)

Now it sounds kind of grim from a software standpoint too. :neutral_face:

Very good to know, thanks for the comparison.


#6

so… a couple of thoughts. went through something similar a few months ago when we got our universal and much of what you described is the same with the PLS6.

when i print vector out of illustrator, i have to be very specific with line weight and color, or it’s automatically an engrave. it must be .001" stroke and 255/0/0. and it’s very similar coming out of autocad. there are ways around that and you can change things, but we haven’t bothered. i know our model shop in princeton has universals and they use yellow for their cut lines.

we had a 3rd party we sourced our machine through and they came and did a really thorough training on how to get results from autocad and illustrator. and i have emails i can use to ask Qs whenever i need to. i’m sure we paid extra for that, but i’m glad we did.

the external air assist is fantastic. really cranks air through. and we have a cone cover on our laser head that really focuses it right down on the cut. there are other options where you can make it exhaust directionally and change the direction by turning the cover. the downside is the cone makes a very low clearance for laser head as it moves across the material.

the universal has an aluminum crumb tray. i hate it. sure, it’s lighter (and that has value because it’s a bigger bed and a much deeper tray). but the honeycomb is easy to bend and magnets don’t work. ::shakefist:: i was able to adapt the pins that someone here designed to fit in our honeycomb, though, and that helps quite a bit.

same focus mechanism. i’ve seen a few people suggest either buying more of the focus tools (or creating your own with a 3D printer) and that’s on our list to do. too easy for someone to misplace it.

but the speed, yes, the speed. night and day. now, granted, we have a 75w laser. but it’s not just the speed/power mix, as @jbmanning5 alludes. it’s the speed of the head on the gantry and how the machine tracks around curves. it just feels more efficient.

to be fair, as @chris1 said, there’s a HUGE difference in cost, so it’s not a completely fair comparison. our universal with the BOFA filter was in the $40-45k range when everything gets added up. and it’s flexible enough that we can add a second tube and have an additional 30w or 75w. adding a 30w would give us much cleaner engraves when there are more subtle effects.

anyway… i can’t speak to the epilog software. but it’s definitely a bit of a mindtwist to go back and forth between the GFUI and the universal control panel. sounds like the UCP is more user friendly than epilog, but don’t be surprised if some of it is that it’s just different enough that it will take some time for you to wrap your head around the different mindsets.

edit: just to add a little bit more. i would LOVE to marry up the features i like in the UCP with the features i like in the GFUI. being able to click on the preview page in the UCP and have the laser head move there and point the red dot is nice. setting absolute coordinates because of the limit switches (and the quick and dirty reset button for positioning). saving your own presets. the huge catalog of general settings to use as baseline starting points. but not having things i get used to on the GF, like the steel crumb tray, being able to reorder operations easily, being able to ignore operations, the bed camera. it makes me wonder how long it will be until someone takes the best of both and makes an even better machine.


#7

Trotec has a vision system available - at least for some of their units. Again, you’re talking 5-figure machines though. The vision system will be on Speedy 300s and up and those start at 25k. Then you pay for every single option pretty much.


#8

Perhaps one of the accessories will be a “Flying laser head”. No fancy autofocus, just a mirror and lens, then dial the speed up to 2000


#9

I see a future where someone takes the existing head and removes a ton of metal to make it less massive and hacks a firmware to run everything faster.


#10

i don’t think the existing head is heavy. it’s bigger, but not heavier, than the head on the universal laser at my office which is way faster.


#11

It’s also held on by magnets so that limits the speed based on how much acceleration the strength of the magnets can withstand.


#12

that may very well be accurate. the universal is clamped on with springs and has bearings on both the top and bottom of the horizontal rail clamping it to the rail.


#13

I suspect your universal also has beefier motors/belts/whatever?


#14

In progress…


#15

Isn’t the issue more that the GF hauls the tube around instead of head weight? I thought most other cutters left the tube in the back and had extra mirrors (and alignment hassles).

Regardless, I liked reading this.


#16

I wouldn’t think so. The tube moves on the slow axis, and it moves at high speed when homing.


#17

not sure the belts are beefier, but the motors may be.

for the universal (can’t comment on others), the tube is definitely enclosed in the back of the machine outside of the bed area. so the tube does not move at all.

not only that, they’re inside steel enclosures inside of there. when you get a new tube, it’s not just a big double walled glass piece, it’s a metal box.


#18

Yeah, good point.


#19

From what I understand, the linear motion control system on the Epilog is quite different. IIUC, they use precision linear rails and bearings with brushless DC motors and encoders to do closed loop positioning. The Glowforge, I believe, uses stepper motors, wheels and an open loop control system like a typical 3D printer.

From what I can tell, Glowforge may be able to improve speed horizontally, but not without losing more horizontal space for acceleration.

Back to front, they appear to be pretty close to as fast as they can move the gantry around without sacrificing quality since some shapes show ringing (insufficient rigidity for the weight and acceleration they’re attempting). But as pointed out, this doesn’t come into play for raster engraving.


#20

Basically, they were optimizing for different things. Glowforge in trying to hit the in-home market wanted the tube on the gantry to simplify the beam alignment step and somewhat off the shelf linear motion and control system to control price and invest their tech elsewhere since there home market’s priorities are believed to be elsewhere (ease of setup/use over speed).