weird stripes in engraved photos

[Craig Hogarth]

lately, i've been getting these weird stripes through my engraved photos, sorta like there's a larger dot pattern that makes a barely visible stripe. sometimes, it's pretty bad, but most people don't seem to notice.

I tried taking a pic, but it's hard to tell from the picture. I don't know if it's my engraver or what?

Can someone post a corel file for me of a photo engraving (for wood or acrylic) that worked well for them? I'd like to get it already processed through photograv along with the original picture as well. I'd like to see if your photograv picture turns out different from the one I run though mine. Please keep the photo within 6x6 inches.

If anyone has any ideas what may be causing thing, please let me know.

thanks.

[Scott Shepherd]

Here's two files processed through photograv and saved in Corel X3, zipped.

[Mike Mackenzie]

Craig,

I would look at the bearings clean them as well as the rail real good if the cleaning helps then try and rotate the bearings upper right to lower middle then take the lower middle and put it on the upper left and then the upper left to the upper right position. You may have either a worn bearing or your X axis belt may need tensioning or possibly changing. I would look at the bearings first.

[Craig Hogarth]

thanks to both. I'll work on it later tonight and hopefully come up with something. Right now, it's only something that I seem to be the only one who can notice, but I'd like to correct it before it gets worse.

[Lee DeRaud]

I don't know about the M-series, but the VL machines really don't like rastering right at X=0. Try moving the picture (and the material) an inch or two to the right and see if the symptoms go away.

[Zeev Goldin]

I usually have that on alder photo frames it is probably the wood.

[Craig Hogarth]

I don't know about the M-series, but the VL machines really don't like rastering right at X=0. Try moving the picture (and the material) an inch or two to the right and see if the symptoms go away.

I haven't had a chance to test anything that was posted here previously yet, but I did run a few tests using the same picture in each corner of my bed. the bottom left one is the one that comes out best although the stripes are visible if you look close enough.

I've had a problem with vector cutting in the top left corner as well. When cutting plastic, i find that more often than not, i have to do a second pass to get through the plastic in the top left section.

My sales rep is supposed to visit here in a few weeks, right before my tube warranty expires so if i can't figure it out, hopefully he can.

[Tom Balz]

Hello,

did you increase a JPG?

I believe that is the problem.

The ULS driver makes also thin stripes by my pictures,
even if I increased a JPG only around 1%.

Making smaller has no effect.

Excuse my English, but the time of school is 30 years ago.

[Lee DeRaud]

I haven't had a chance to test anything that was posted here previously yet, but I did run a few tests using the same picture in each corner of my bed. the bottom left one is the one that comes out best although the stripes are visible if you look close enough.I haven't tried it, but I suspect the anomaly I've seen occurs at both left and right edges. I think it's due to the fact that the VL series has no overrun/ramp area outside the normal engraving area. The stripes (good a word as any) only appear when there is engraving right at that edge. I first noticed it when tiling a large engraving onto multiple pieces, since I usually have some blank margins. (I've got a piece of granite with that effect showing, but the stuff is next to impossible to photograph at that level of detail.)

I've also seen the vectoring anomaly you describe: different animal altogether. You'd think the beam would be strongest at the upper-left (closest to the tube), but that's not how it seems to work. I haven't heard an explanation for it yet that didn't involve a whole lot of semi-implausible hand-waving.

[Craig Hogarth]

tom, i'm gonna have to test that as i'm not sure. on occasion, i'll resize a picture a few times, although i usually undo it before i resize again.

lee, these stripes run down throughout the picture and are of equal size and equidistant from each other. my wife only notices when i point it out, so maybe i'm being a bit picky.

[Craig Hogarth]

Craig,

I would look at the bearings clean them as well as the rail real good if the cleaning helps then try and rotate the bearings upper right to lower middle then take the lower middle and put it on the upper left and then the upper left to the upper right position. You may have either a worn bearing or your X axis belt may need tensioning or possibly changing. I would look at the bearings first.


Thanks Mike, I did a good cleaning to the rail yesterday before doing two photographs and it works great now. The bottom part was neglected and I think that was the culprit.

[Mike Mackenzie]

Craig,

I am happy to hear that it only needed some cleaning. this should be done on a regular basis.

[Craig Hogarth]

I do clean it every 2 days or so. Whenever i clean the lens, i use the swab to clean the rails. Apparently, i just forgot all about the bottom rail. I seriously think it's been 6 months since I last cleaned it. :o

I'm gonna rotate the bushings as you suggested, i imagine the bottom one isn't in the best shape. I just have to go buy allen wrench to fit the screws in the head.

[Mike Mackenzie]

Craig,

If it is all OK now I would leave it! you would remove the bearings with a nut driver. Two things to caution you with one if you rotate the bearings do not over tighten the them just bring them up snug and a very little umph (if that is a word) second there are very small wave washers between the bearings and the carriage they can get lost very easy just make sure that the wave washer is there and in the right spot.

If you need instructions PM me your e-mail and I will send them to you.

Again I would leave it the way it is for now if you start to see any other issues then do it. You may end up replacing the set but we would do the rotating first to see if that helps.

[Craig Hogarth]

ok, i'll wait on it. I talked to my sales rep in vegas last week and he's gonna come out in a couple weeks to replace them anyways. We worked out a full maintenance deal when i purchased it and he wants to come check out the wattage before my warranty expires :D