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Brian Lamb
04-07-2016, 10:24 AM
I was just playing around with cutting out a leather key chain fob and found it difficult in Corel to draw a shape. So I used my CAD system which is Alibre and drew up the part and made a DXF file and imported it into the Corel software. Went to cut with the laser and it cuts each section of the complete path in an odd order, jumps all around, does a line, then opposite side of the part does and arc, then back to another side and does another line and so on. Eventually gets it all done, but how do I get the DXF file to cut in a continuous path? Do I "weld" the DXF file together before I send it to the laser? Something else I'm missing?

Richard Rumancik
04-07-2016, 11:28 AM
It is hard to say if you can do anything in Alibre to improve it - there might be, but it could be time consuming to find a way. What I would likely do is segregate each contiguous path in CorelDraw and just "combine" the vectors into a single path. If it should be a closed path (eg an outline cut), then make sure the path is actually closed. (If it will fill with a color, it is closed. If it won't fill with a color there is a gap somewhere.)

You might get by with cutting an open path but I like to close paths to make sure it is truly contiguous. Filled shapes must be closed paths.

If a path looks closed under magnification but won't fill, I usually select the object, "close path" -> straight lines and then it will fill. There might be a .001" gap somewhere due to translation roundoffs but a break is a break as far as Corel is concerned.

Brian Lamb
04-07-2016, 12:56 PM
Thanks Richard,

That did the trick, in Corel X7 it was "Join curves", then you have to "apply" when the box opens up. That closed the shape so I could fill it. Went and retested on the laser and it did cut a continuous path around the outside that way. I appreciate the help!

This will be a big help as I don't understand how to, or maybe I don't feel that I can draw as accurately and quickly in Corel as I can in Alibre. It's a lot easier there to draw a quadrant and then mirror images and get accurate angles and dimensions. Plus, I have a lot of parts already drawn and it will save re-doing them completely in Corel.

Kev Williams
04-07-2016, 2:04 PM
You need to use the OUTLINE function, will will draw a single, closed shape from any other closed shape, as long as all nodes are connected, which they usually are in DXF files, and regardless of how many multiple copies of the shape are hiding beneath in other layers...

I just explained the outline function in this thread just yesterday, with pics--
http://www.sawmillcreek.org/showthread.php?242705-Holes-cut-to-many-times

Brian Lamb
04-07-2016, 10:55 PM
Hi Kev,

Thank you, I read a portion of what you posted in the other thread, but didn't quite grasp it. I went back and looked at it after your second post and it makes better sense to me and I was able to do just what you said, use outline and set my nudge to shift the outline over and remove all other pieces, then move back. Thank you for the tips, I have a lot to learn in Corel....

Bill George
04-08-2016, 11:09 AM
Brian if its any help I grew up so to speak using AutoCad, and I find Corel difficult to use for exact dimensions. Draw in CAD export DXF to Corel to use with my ULS machine.

Brian Lamb
05-20-2016, 7:55 PM
Bringing this thread back up again, having trouble today with cut order. I had the inside cuts black, so they should go first, then the outside cuts blue, so they should cut after the black. I did use an imported DXF file, but using Kev's suggestions used Outline and shifted over.... oh wait, I used duplicate instead of nudge, maybe that's the problem with it cutting the outside once in broken lines and a second time as a continuous path.... will go test that theory.

Now, the problem of cut order still persists though.... I have setting in the ULS print drivers that I have questions about, took a couple of pictures of the screen.

First one, in the print window, should I be set on grayscale or RGB?

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This is the X-600 Properties window, it has "Vector Optimizer" as off

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And these are the options there, what do they mean? Enhance or sort?

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Brian Lamb
05-20-2016, 11:04 PM
I re-did the corel file using the nudge instead of duplicate. That got rid of the multiple passes around the perimeter. It did not however make the cutting order correct. So, I went in and tried the "Enhance and Sort" option and that made the machine cut the insides first, then the outside.

We did have a power blip the other day and windows went buggy, so maybe my print settings got messed up. Hopefully someone with a ULS laser can see what theirs are set on.

Mike Null
05-21-2016, 7:02 AM
Brian

You should work with the RGB palette. There may be a ULS palette as well but it will be RGB based.

Tony Lenkic
05-21-2016, 9:11 AM
I re-did the corel file using the nudge instead of duplicate.



Brian,
Is there any valid reason why you convert Corel file to DXF? You know that ULS will engrave and cut direct from Corel cdr. file.
I have run my ULS V-400 that way for years. Now it is sitting in the corner awaiting new home since Trotec Speedy 300 does all the jobs on time and I have room for single unit.

Brian Lamb
05-21-2016, 9:53 AM
OK, so set the output colors to RGB? I do use the ULS Color Palette which is RGB. I only use the pure RGB colors, blue, red, yellow and so on.

As for DXF files, it's not converting Corel into DXF, it's the other way. I can design parts in Alibre (my CAD system) a whole lot easier, especially for precision shapes and complex contours. Then it outputs DXF files, I then import them into Corel and convert them to a cdr file to use on the laser. My only issue with that is I find any DXF file tends to laser one portion of a line at a time, in no particular order. That is why I use Kev's suggestion and outline the shape to combine it into one continuous path.

It would be nice if you could pick and choose your starting points and order like I do in CNC machining, especially for vector cutting. I don't know enough about the software, maybe that's possible and I just don't know how to accomplish it.

Tony Lenkic
05-21-2016, 10:02 AM
It would be nice if you could pick and choose your starting points and order like I do in CNC machining, especially for vector cutting. I don't know enough about the software, maybe that's possible and I just don't know how to accomplish it.


That could be accomplished with object manager in Corel draw but it will be time consuming. Combining objects and setting cut path takes time as is learning Corel to start with.
Can you show us complexity of your design?

Ross Moshinsky
05-21-2016, 10:30 AM
OK, so set the output colors to RGB? I do use the ULS Color Palette which is RGB. I only use the pure RGB colors, blue, red, yellow and so on.

As for DXF files, it's not converting Corel into DXF, it's the other way. I can design parts in Alibre (my CAD system) a whole lot easier, especially for precision shapes and complex contours. Then it outputs DXF files, I then import them into Corel and convert them to a cdr file to use on the laser. My only issue with that is I find any DXF file tends to laser one portion of a line at a time, in no particular order. That is why I use Kev's suggestion and outline the shape to combine it into one continuous path.

It would be nice if you could pick and choose your starting points and order like I do in CNC machining, especially for vector cutting. I don't know enough about the software, maybe that's possible and I just don't know how to accomplish it.

Why not print directly from Alibre?

Brian Lamb
05-21-2016, 12:54 PM
Hi Tony,

I will attach a screen shot of the design in Alibre, just an earring the wife wanted to try. If it is a matter of drawing the original Alibre file in a specific order, I could probably do that, just not sure where to start.

When I'm doing something like this, in Alibre it's a 5-10 minute design, I think because it has lots of easy drawing tools to work with, and I can draw portions and mirror image and all sorts of things, like automatic fillet radii.... If I try the same thing in Corel, at least so far, I'm in there for hours trying to accomplish the same thing. This is why for odd shapes I resort to the CAD software, for text, signage and things like that, Corel wins hands down.

Ross, I wasn't aware I could, or at least know how to print directly from Alibre.... I do have a copy of Alibre on the shop computer, will have to see if I can print from there. My ULS manual is pretty sketchy on how to print from anything other than Corel, AI, or DOS based programs, so if there are pointers or suggestions, I'm all ears.

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Tony Lenkic
05-21-2016, 2:34 PM
Brian,

I see there is a "PRINTER" icon on your program. You should be able to send a print file to ULS directly from Alibre.

That image is quite simple and small to organize cut order in Corel with "object manager" form a docker or even two color process where inner parts are one color to cut first and outer perimeter as a last cut.
If you have question on object manager how to place them in order we can give you help on that.

Lee DeRaud
05-21-2016, 5:20 PM
And these are the options there, what do they mean? Enhance or sort?'Sort' handles the inside-first, outside-last questions, but if the curves aren't well and truly closed, I'm not sure it can determine that properly.

'Enhance' is supposed to minimize non-cutting (move) time, and presumably total cut time. I'm not sure the savings are worth the head-scratching that results, given that I'm pretty short on hair already. YMMV, but it does such odd things that I've given up on it: too many instances where a single Corel curve entity gets split into multiple chunks that cut separately, sometimes to the point of appearing random.

With both turned off, it cuts in Corel Object Manager order...at the moment I can't recall whether that's top of the list down or vice versa. I've never really felt the need to change colors to manage cut order.

Lee DeRaud
05-21-2016, 5:29 PM
I see there is a "PRINTER" icon on your program. You should be able to send a print file to ULS directly from Alibre.A ULS will cut from anything that can interface with a standard Windows print driver, if (and that's a big "if") you can map the "print page" coordinates to "world" coordinates 1-to-1. E.g. I was able to get output from DesignCAD to the ULS, but for some reason getting that particular CAD program and the laser to agree on the definition of "inch" was more trouble than it was worth.

Kev Williams
05-21-2016, 5:43 PM
have you tried, under the 'arrange' tab, "to front"?

This would be assuming you've got all your lines connected,

I just tried this and it works--- very easy to test yourself..

I typed the numbers 2 4 1 5 3 6 - not with spaces but as separate numbers so they're separate objects ( or curves )

NOW, if I group and send them to the laser as typed, it will engrave 2 then 4 then 1, etc...

But I want to engrave them 1 2 3 4 5 6 --

To do this, I clicked on '1', then pressed the Ctrl-Home keys-- this moves the 1 to the front.
The Ctrl-Home key is a shortcut for clicking the ARRANGE/ORDER/To Front Of Page tabs...

I then did the rest of the numbers in numerical order, sent it to the machine, and it DID engrave them in numerical order!

Don't need to change any colors doing it this way. If you have a LOT of objects, set your nudge to an inch farther away than your overall graphic is wide-- ie, if your earring was 6" wide, set the nudge to 7"...

Then, click each object, then Ctrl-Home, then the right arrow key to move it out of the way. Do this till you're done. Then just nudge the whole thing back, and go...

Just make sure your 'ENHANCED SORT' is NOT ON in your print driver, then it should engrave in order...

Lee DeRaud
05-21-2016, 7:54 PM
have you tried, under the 'arrange' tab, "to front"?

This would be assuming you've got all your lines connected,

I just tried this and it works--- very easy to test yourself..

I typed the numbers 2 4 1 5 3 6 - not with spaces but as separate numbers so they're separate objects ( or curves )

NOW, if I group and send them to the laser as typed, it will engrave 2 then 4 then 1, etc...

But I want to engrave them 1 2 3 4 5 6 --

To this, I clicked on '1', then pressed the Ctrl-Home keys-- this moves the 1 to the front.
The Ctrl-Home key is a shortcut for clicking the ARRANGE/ORDER/To Front Of Page tabs...

I then did the rest of the numbers in numerical order, sent it to the machine, and it DID engrave them in numerical order!Ok, if I read that correctly, that sequence ends up with '1' at the back and '6' at the front, so apparently it cuts back-to-front (bottom to top on the list) by default.

Note that, if you think of a drawing as foreground objects laid onto background (as they'd have to be if they were filled), that also corresponds to outside-to-inside, which is backwards of what we want most of the time.

Dave Sheldrake
05-21-2016, 7:58 PM
Try "PEdit" then select "Join" in most cad packages

Tony Lenkic
05-21-2016, 10:36 PM
Ok, if I read that correctly, that sequence ends up with '1' at the back and '6' at the front, so apparently it cuts back-to-front (bottom to top on the list) by default.




That is correct, In object manager cutting order is from bottom most object upwards.

Kev Williams
05-21-2016, 11:39 PM
-- yes- the same as my original typing, it did the first typed number first, because each new typing is put at the front.

Gravostyle has a nifty way of arranging the cutting order; the order you continually select objects becomes the arranged order automatically- But the neat thing is, if you 'box-select' an otherwise ungrouped batch of objects and send to the machine, it will run in the order you first selected them. BUT, if you GROUP the same batch of objects and send THAT to the machine, it will run in the REVERSE order you selected them... For tool engraving this comes in handy when engraving things like stainless or anodized aluminum, that wears down the tools-- if only the tail end of your engraving suffers slightly from a worn tool, you can run a second pass in reverse to clean up only what needs it, without doing a bunch of re-arranging...