EZ CAD dxf files are jerky when engraving - fiber marking laser

[Mike Brostrom]

Hey everyone - I have a China 20 watt MOPA fiber galvo laser running EZ CAD 2.10.xx, it's about 1.5 years old. I'm engraving a small piece of stainless, almost the size of a business card. I'm trying to engrave a dxf file that I hatched and then grouped together. I have the hatch line set a .045mm, speed 600, power 100... The problem I'm having is that once it starts to mark, it will start and stop repeatedly, almost like it's buffering or having a "hiccup" of sorts. I've tried slowing it down, changing the hatch, all to no avail. This is a dedicated cpu only running ez cad. If I were to convert this to a png or jpg, I could engrave it at any speed I want. The problem seems to be with dxf files. Sometimes it will work, but most of the time it will jitter like this. I like using dxf for a variety of reasons, so I really want to fix this. Can anyone send some help my way please?
Thanks - Mike

[Kev Williams]

Mine's done that before, I believe my problem was that the computer was downloading MS or AV updates. Even if the computer isn't online, it could be doing stupid stuff via 'Task Scheduler' that's eating resources and intermittently shutting down USB output. Have you tried changing out your USB cable, and/or changing the port it's plugged into?

Is your auto-rotate on? There's always a slight pause while EZcad does the rotating and redrawing...

Which hatch are you using, the connected high-speed hatch or the disconnected high-quality hatch? The high-speed hatch can sometimes have issues, usually with just drawing, but could be with the output too...

You say you 'hatched and then grouped together' your file? Are the parts grouped, or combined? Or just separate graphics that are overlapped? Not sure why any of these would matter, but if they are grouped or combined, try separating them and just overlapping them as 2 individual groups. OR, if that's what you're doing, try the opposite!

[Mike Brostrom]

Kev, thanks very much for your reply. This computer is not connected to the web and I made sure task manager is not running any other programs. I will try switching USB outputs just to try it.

Auto rotate is off.

I'm using Hatch 1, is that what you are referring to? All of the other hatches are turned off (2, 3 are off).

I had the file, which was just a vector file and imported that into ez cad. Then, I selected the whole vector file and hatched it. From there, I clicked "group" so I can move the whole file around the page and it doesn't list each and every vector line in the upper left corner of the screen.

I tried at one point to engrave each letter and vector piece by piece, but it still "hiccups" and pauses. Kev, if you import a vector with just lines, then hatch it with ez cad, can you engrave at speed 600mm/sec or faster with out problems or jerks? If so, something is wrong with my system and I just can't figure it out. I wonder if the computer it came with, which is a desktop with 2 gig ram and windows xp. That's all that is installed on it, but I wonder if it's not quite enough...

[Jacob John]

I usually try and export to PLT and so far it seems to be a less buggy format for fiber lasers. I do use DXF and have not experienced your specific issue.

[Kev Williams]

Mike, hatch TYPE is what I was referring to, sorry--

These are two hatches I was talking about- the left one is the 'quality' hatch, the red edges do not engrave, only the blue engraves. The right one is the 'speedy' hatch, again, only the blue engraves but as you can see it's ALL blue, laser always fires. On small monitors the icons are hard to tell apart, especially the red edges, so how I tell them apart is by the length...
blue-redhatch.jpgbluehatch.jpg

The fast hatch is MUCH faster than the quality hatch, like 4x or more in some cases. Several reasons for this, one being the fact it takes more time for the laser to turn off and back on with every hatch line in the quality hatch, the fast hatch only shuts down to start engraving in a new place. And how they engrave are totally different. The quality hatch will move in ONE direction only, as in, if on a 45° hatch it starts upper left, the laser will sweep ONLY down and right. This means any thick but hollow objects, such as a thick outlined circle, gets swept as a whole, and it can take lots of time to sweep a whole circle just to engrave the 1/2mm thick outline. But the fast hatch engraves ONLY the outline, following it around as you would draw it. The fast hatch sweeps little or no 'dead air space' so it saves a ton of time. But there is a downside- since it follows just a path, the engraving around the circle means it engraves in two directions, and the look of a hatch cut from bottom up is totally different than a hatch cut from top down, and depending on the the engraving, this is very noticeable. For deep engraving and most anodized stock, it's not noticeable, but if you're lightly etching stainless, it can look atrocious! I did a watch back resto right after getting my fiber, so I was still learning, this was one of my first tests, using the fast hatch...
rado1.jpg
the dark areas happened on the top/down sweep, bad...

this looks much better...
rado2.jpg

One other issue with the fast hatch is that sometimes it will make connections between 2 objects that are separate when it shouldn't, so checking first is necessary!

IMO the fast hatch can be SO fast that I believe it's possible for the machine to engrave faster than the data stream, and with no pause available, the laser has to wait. This could've been my problem, might be yours.

The other two hatch types are the uni-directional (the 'slanted lines' icon) and island fill. I actually did the watch back using the unidirectional. It's slow because it only engraves from left to right, but the finished look is very nice. If you've been using the fast hatch, try the quality or the uni types, see if that helps!

[Mike Brostrom]

I had no idea about the fast hatch, I never saw those red corners before! I had it set on the quality, slower button you showed in your post Kev. That is the one I like to use and that is what is jerking. I switched over to the fast one and wow is it quick! It did the letters and numbers just fine, but when it got the small graphic with many vector curves, it was not able to realign itself perfectly when it returned to finish that vector hatch, so it leaves a thin line behind in the anodized aluminum test part. I tried the other hatches and they too leave a line or noticable mark behind.

Any other thoughts? Do you think the computer is too laggy? In the past, I have had the "out of memory" warning, but not in some time now. I have no idea what else it could be...

[Jacob John]

I don't know if this is something you do Mike, and it definitely adds a little time to an order, but I always test engrave on an anodized black blank. I find they show any hidden issues with your image and helps fine tune it.

And Kev, GREAT explanation! Thanks for writing that up.

[Kev Williams]

as for re-aligning- it SHOULD be re-aligning perfectly, so if possible, check the screen to see if the fast hatch actually drew in the errant lines, it's one of the issues I mentioned.. however, the 'tried other hatches' and it's still doing it, is a bit weird...

However, if your screen shows different than the laser is doing, then your laser may have a problem... Mine had an alignment problem, and one of the cures I tried, and I believe worked, was to pull the cable from the control board inside the machine- Mine has some goopy soldering done, but otherwise looked fine, and after I reattached the cable it was fine. Triumph sent me a replacement scanhead just in case, but I don't think it was the problem.

I can't remember how many times a computer cable was the cause of a machine problem. The only laser I own that hasn't been affected by a connection is my big Triumph. And virtually all of my rotary engravers I've had a connection issue with at one time or another. With your machine sputtering and now possibly mis-cueing engraving, it wouldn't surprise me a bit that reseating the cables to and inside the machine might take care of this..

[Mike Brostrom]

I actually did the most recent test engraves on an anodized aluminum blank and that is how I could see those super thin lines that engraved where it shouldn't, connecting letters and words together.

I finally found the "auto rotate" feature and shut that off. I would estimate that helped the issue about 25% in the right direction.

I neglected to mention I also have the camera feature built in to the scan head. I shut off the camera thinking that it could be adding a lot of draw and system resources, possibly causing some of the lag. After I shut that off and the auto rotate, it's working almost flawlessly with no jitters or jerks. This leads me to believe it is in face the compute. I happen to have a spare i7 processor on a board with 8 gigs of ram and a decent graphics processor. I picked up a cheap SSD and will install Windows 7 32 Bit and report back in a week or two with the results. That will certainly tell one way or the other what is going on. Thanks everyone for your comments!

[John Lifer]

Kevin, I was running a fairly quick job bleaching some plastic arts and had initially set up using the quality hatch. Usually my std. I changed to the fast hatch andv reduced time from 32 to 18 seconds. Way good time reduction with zero perceived difference in image quality.

[Jacob John]

Kevin, I was running a fairly quick job bleaching some plastic arts and had initially set up using the quality hatch. Usually my std. I changed to the fast hatch andv reduced time from 32 to 18 seconds. Way good time reduction with zero perceived difference in image quality.

So is the quality hatch mainly for tiny logos when you're trying to get greater detail (like being able to read tiny words)?

[Kev Williams]

The fast hatch's engraving output is just as 'high quality' as the quality hatch (those are my made up names btw ) -- I was showing someone yesterday my fiber, and I engraved an outline of "TEST" at less than 1mm tall at 500 speed... under magnification the engraving was perfect, straight lines, sharp corners, perfect curves on the "S" - the timer said it took .11 second, wow! So basically the detail is going to be there!

But along with light reflection issue with the fast hatch, there is also the issue of overburn at the corners where the hatches change direction, and since there are no corners in the quality hatch, that will help. For very high quality, use the unidirectional hatch, since not only does the hatch routine sweep in just one direction, each hatch line is engraved in just one direction, so every hatch line is essentially identical, no reflection issues. Unidirectional is the default for photo engraving...

[Mike Brostrom]

The quality hatch works best for fine detail. For many jobs, the fast hatch is the way to go. I always test first on some scrap pieces though.
Back to the original topic...I found my old copy of Windows 7 64 bit and dusted off my old machine. It is running an Intel i7 at 3.4ghz with 32gb of ram and I put in a solid state hard drive with 64 gig of capacity. It also has a cheap-o 1gb HD video card. After putting EZ Cad 2.10.x and using the 64 bit driver, it works like an absolute champ. There is no question the machine that came with the laser was not capable of running larger dxf files. I can manipulate the images all over with no lag and no more jerking or jittering.
I should point out that I also tried 4gb of ram on the 32 bit version of Win 7 and that worked well, but why not use the added RAM I had here as well. Keep this in mind if you ever get the "out of memory" warning or experince that jerking or skipping with dxf files!

[Jacob John]

The quality hatch works best for fine detail. For many jobs, the fast hatch is the way to go. I always test first on some scrap pieces though.
Back to the original topic...I found my old copy of Windows 7 64 bit and dusted off my old machine. It is running an Intel i7 at 3.4ghz with 32gb of ram and I put in a solid state hard drive with 64 gig of capacity. It also has a cheap-o 1gb HD video card. After putting EZ Cad 2.10.x and using the 64 bit driver, it works like an absolute champ. There is no question the machine that came with the laser was not capable of running larger dxf files. I can manipulate the images all over with no lag and no more jerking or jittering.
I should point out that I also tried 4gb of ram on the 32 bit version of Win 7 and that worked well, but why not use the added RAM I had here as well. Keep this in mind if you ever get the "out of memory" warning or experince that jerking or skipping with dxf files!

Yeah with those specs you should have no issues at all.

[Kev Williams]

just for ref-- My fiber came with a laptop with 32bit win7 Ultimate, don't remember the ram, and since moving the laser into the garage I just hooked it up to my 'downgrade' Dell Optiplex 760 running 32bit XP pro w/a 3gig 2-core proc and all of 3gigs of ram, and I haven't noticed a bit of difference in anything the machine or the program does. The complicated dxf's that took 10 seconds to load on the laptop take 10 seconds on this machine too...

I'd love to hook my fiber up to my 2-proc 8-core 32gig ram 64bit Win7 Pro Dell T5400 Precision, but honestly, other than the time it takes to load my programs has shortened somewhat, all that extra computer power hasn't speed up what Corel or Gravostyle does vs my old XP computers in the least...?