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Russ D Wood
05-04-2013, 5:40 PM
Just got my laser. I have it working (almost). I can do a really nice raster image but I can't currently do a vector CUT. The machine and software is not the issue I don't believe. I believe the issue is that there must be some term / adjustment / setting / that I'm overlooking. So here is my question, if I have a thin piece of ply (1/8th inch) what would be a good set of starting points to try and use for doing a vector cut? I.E. speed, power, etc,. Or am I all wet and it is very machine / software specific? I have a 40w co2 laser. Thanks in advance for any assistance. Russ

Glen Monaghan
05-04-2013, 6:23 PM
Pretty hard to say without knowing what machine you have and what software you are using. Depending on those, you may need to use a certain color for cutting, or you may need to make your cut line a certain (or maximum) thickness to enable cutting.

Russ D Wood
05-04-2013, 9:51 PM
Hi Glen, I was reluctant to mention the laser or their software because I'm sure the problem is on my end not theirs! :D I did finally get a vector to cut but only in some very light cardstock. I also sort of figured out how to get the rasters to etch / print a little darker, was just a light chocolate brown before. I really appreciate the hints towards line weight or color, had not thought of that, thanks. Back to playing some more. In a past life I did a lot of development work for HP and their original laser printer. We had tons of test pages and complete writeups on how each image was created and what was supposed to happen when you printed it. I can't imagine that there isn't that sort of documentation available for laser engraver /cutters given the length of time they have been available. Oh well. Thanks again. Russ

Glen Monaghan
05-05-2013, 12:06 AM
Well, it may well be a problem on your end and not theirs, but I don't think anybody here is clairvoyant enough to be able to tell you how to deal with the problem, which ever end it is on, without more information. There are just too many variations in systems and there's absolutely no problems with saying what you are working with... if it's your mistake, I'm sure someone here can and will clue you in!

Rodne Gold
05-05-2013, 3:39 AM
Most laser software will want either a specific colour and/or a specific line weight to vector cut. You might find your line colour is wrong and the laser will default to a set power level when vectoring or that it is too thick and the laser will interpret it as a raster and wont move like a plotter.
Does your laser MOVE like a vector cutter (plotter) when trying to vector cut or is it acting like a raster engraver (like a dot matrix printer)?

Walt Langhans
05-05-2013, 9:29 AM
I'll ask the basic question then. Are you 100% sure you have it properly aligned and is it in focus. I ran mine for a day or two before I realized that the mirror on the nozzle assembly was capable of and need to be adjusted. It was close enough that it was doing an ok-ish job but once I got that aligned and adjusted my nozzle assembly so that it was perfectly perpendicular to the table everything was perfect.

Roy Nielsen
05-05-2013, 11:48 AM
Russ,

At a minimum, please share what software you're using; it is really hard to give advice without at least knowing that. Since you can raster, it sounds like your machine is basically functional and at least fairly in alignment.

I'm still learning my machine, running LaserCut 5.3, and recently found that some default settings are way off from optimal, especially frequency (20,000 is the default, but in the tens to hundreds works much better depending on material and speed). Getting height between the lens and material right makes a big difference, too. When I first tried to cut some ~1/4" birch, I had to run at a snail's pace at high power and ended up with black and crispy edges; I can now cut at around 4-5x faster than the first try and while the edges are still pretty black, they are much better than before. I've also about doubled the speed for cutting 1/8" birch ply.

As for documentation, I'm assuming that you might have a Chinese machine, for which GOOD and complete docs appears to not exist. I had my machine for a couple months before I figured out what "conner power" is (corner power) by searching here on SMC. I'm still trying to figure out how to start a job from where the head is positioned, it will only start where I absolutely state (one setting) or starts around an inch or so +X and -Y of the bed's center.

You may also want to build a spreadsheet or notebook that contains optimal settings for various materials. I cut a small square and try to find the right balance of power, speed, frequency settings and even include room air temperature and chiller temperature (in case those make a difference when/if we ever get to summer here).

As a cost saver, I've found that 1/8" cardboard vector cuts almost exactly the same as 1/8" birch at the same settings. If it cuts completely through the cardboard, it will most likely cut cleanly through the ply.

Good luck,
Roy

Russ D Wood
05-05-2013, 4:36 PM
Thanks gang for all of the replies. The problem was / is defintely on MY end and not the machine. I finally got it to cut some cardstock so I knew it was in fact working, then I tried a bunch of different materials and NO CUTS. So I found a scrap of balsa left over from another hobby and tried it and low and behold cuts like I thought is was supposed to. So now the question is, I need to find US suppliers of laser cuttable 1/32 inch to 1/8th inch plywood. I now know it has to be the right kind of glues used to make the ply. So who supplies it? Next question a lot of model kits that are so called 'laser kits' have a peel and stick backing, is this something that can be added to the sheets prior to cutting or do you order the ply / material with this already applied? Again I really appreciate all of the comments who have passed on to me, BTW the machine (since it was not their problem) is the FSLaser Deluxe Hobby system with their Retina software. Russ

Bruce Dorworth
05-05-2013, 8:26 PM
What wattage is the machine? Where are you located? What type things do you plan to make with the laser? I cut a lot of 1/8" MDF from Home Depot on my laser.

Bruce

George Carlson
05-05-2013, 9:27 PM
You may still have an alignment problem. I would think a 40W laser should be able to cut through 1/4" Birch plywood at about 8mm/S at 100% power. It sounds like yours is not cutting as well as it should.

Bruce Dorworth
05-05-2013, 11:19 PM
Or a focus problem

Russ D Wood
05-06-2013, 12:39 PM
Once again I want to thank all of you that have replied. I am a model builder and have been putting together for years, both scratch-built and from kits. I love the so called 'laser kits' where everything is precisely cut from sheets of really thin plywood and you just assemble much the same as a plastic kit. So now I'm retired and have cad and cam skills from my past life so I bought a table top 40w co2 laser from FullSpectrum. I want to be able to cut the really thin sheets of ply that is found in those 'laser' kits. That particular material has all of the characteristics that I am looking for. So far all of MY sources of really thin ply seem to all have the wrong kind of resins or bonding agents that are used in the manufacture of the ply. The substrate that I am looking for ideally would be the 1/32, 1/16, and 1/8th plys that are laser cuttable and possibly even have the peel and stick backing. I know I can order single small sheets from a few companies at expensive prices (in my opinion), what I am looking for is a commercial distributor of this kind of product. I wish to order a large amount of material(s). Thanks again for all of the help, it is most appreciated. Russ

Bert Kemp
05-06-2013, 1:25 PM
Home depot has 1/8 and 1/4 plywood altho not the best quality , I find woodworkersource or Rockler has much better BBply.

Bert Kemp
05-06-2013, 1:38 PM
That machine will cut 1/4 BB ply at about a speed of 20 I use 17 just to make sure. I find a lot of times I get a spot or 2 where it didn't cut all the way thru. 1/8 inch I cut at 30 speed.Might even go a bit faster but I like to make sure it cuts all the way thru. Please keep us posted as to how this works for you.

Roy Nielsen
05-06-2013, 7:38 PM
If you're near a Woodcraft store, they may have 1/8" and 1/16", not sure about 1/32", birch ply in stock and if not should be able to order for you. Hold on to your hat for the sheets under 1/8". You might also want to check with cabinet makers to find out where they get their materials or even if they will resell to you, if you're looking for full sheets.

Mike Null
05-07-2013, 6:04 AM
You can contact Mike Kowalczyk who is a long time SMC member. http://www.displayideas.com/

I've used his wood before and it was of good quality.

Russ D Wood
05-07-2013, 4:30 PM
Well so far I have been through all of the focus, leveling, distance, clean up steps as listed in my manual. I can cut everthing BUT ply so it is still my assumption that it is my stash of ply scraps that MUST have the wrong glue for laser cutting. The top layer of wood is awesome then nothing cuts below the top layer (first glue layer). If I stick in a 1/4 inch piece of balsa (NO GLUE) it cuts cleanly and has no issues. I have ordered some laser cuttable ply from a supplier that states, that I SHOULD have NO problems with his stuff. So we shall see if its me or the machine. Everything else works exactly as it shows in the manual. The machine is actually a pretty neat little box and I'm having fun inspite of the cutting issues. Your comments and suggestions have all been taken seriously and I do appreciate you trying to help, thanks. Russ