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George M. Perzel
10-18-2006, 8:24 AM
Hi all;
See attached image-Inner black ring on upper ornament was done by normal rastering along with the rest of the image. To save time, I changed the ring to a contour set of 4 rings spaced .005" apart and vectored them in the bottom ornament. Top ornament took total of 3 min 17 secs- bottom took 2 min 41 sec, almost a 20% time savings.
George

Mike Null
10-18-2006, 10:00 AM
George:

Very good tip!

Dave Jones
10-18-2006, 2:25 PM
That's a bigger difference than I would have guessed from just looking at it. Very interesting.

A couple of other thoughts. There are fonts that mechanical engravers use which are made up of just vectors with no fills. Possibly one of those used for the name of the town might save time too.

Since you are using several concentric vector circles now, you can also play with spacing on them to create some interesting looks. For example evenly spaced concentric circles creating a sort of ribbed circle. Or circles that get closer together so the spaces between then get thinner and thinner. Or adjusting the speed or power on concentric circles to change the shading. Using the same number of circles you use now it shouldn't change the time any, but can change the look.

BTW, I like that basic look. I may have to steal that look and try some of those using my local town landmarks. :D

Oh, and George, the wood arrived today. Thanks.

Mike Null
10-18-2006, 3:04 PM
Keith posted those fonts a couple of weeks ago but I haven't been able to get them to work--even to open.

Dave Jones
10-18-2006, 3:51 PM
Do you know what thread that was in? I have a few single and multi-line fonts that came with AutoCAD, but they are fairly basic. I'd like to try some others.

Jim A. Walters
10-18-2006, 8:28 PM
Try this one:

http://www.sawmillcreek.org/showthread.php?p=345180#poststop

Bill Stein
10-18-2006, 8:57 PM
George,

Very nice work and a great tip! What kind of wood are you using? I really like the contrast that you are getting.

Bill

George M. Perzel
10-19-2006, 1:50 AM
Hi Bill;
The wood is cherry-here's a link to an offer for some at pretty good prices.
http://www.sawmillcreek.org/member.php?u=2842

George

Rodne Gold
10-19-2006, 2:55 AM
Be careful of using vector engraving with lettering and so forth , its slower than rastering small letters and gives rise to ramping problems. It is also more likely to give rise to missteps and machine errors.
There are lots of strategies to shorten engraving times , using vectors for borders is a very good one.
Others are reducing resolution on some parts of a job , using the stamp cluster mode to do stuff that requires a lot of travel of the head between elements , using different colours for different parts of a job etc.
We had a huge order of tags to do and reduced cycoe times from over 1 min each to 14 secs by using various strategies. This saved major time on the runs (well over 10 000 tags)

Mike Null
10-19-2006, 8:08 AM
Rodne:

Would you mind posting the drawing for such a job. Also when you use vectors for borders are you using the technique proposed by George of using the contour tool?

Richard Rumancik
10-19-2006, 10:05 AM
Rodne, can you elaborate on what you mean by stamp cluster mode? I understand the end result; you are trying to "group" the raster elements in some way. I have often wanted to raster in "columns" rather than right across the bed. Unfortunately the driver on my Mercury wants to go full width left-to-right regardless of grouping, sorting, front to back order, colors etc. I asked GCC and the only idea they had was to convert the raster to vector. We both know this is not always a solution.

I agree with your comment on the problems of using vector on small text outlines. I think there would be deep "holes" at the ends of travel and sometimes it looks darker.

Even when doing vector borders I found that the ends of the lines had a dark point. If I do a wider vector border (say .050" wide, maybe 15 lines at .004 wide) I have found that it helps if I rotate the start/stop endpoint so they are not all in one corner of the border. At least it is not as obvious that one corner is darker. With a "round" border maybe a spiral would work better than concentric circles, then edit the endpoints.

Rodne Gold
10-19-2006, 11:39 AM
Richard , to avoid the start and end point problems change your ramp to on - Im not sure if its software or in the machines menu , I have a suspicion that its in the machine settings accessed from the front panel on the Mercury, I havent used mercuries for 3 yrs now , we run explorers and spirits

In the driver there is a cluster setting , however on the mercury it might just apply to stamp mode.
You can set a value for cluster , lets say 5cm , then any objects with more than 5cm white space between them will be lasered independantly , ie the head wont fire - scan across - fire for the next object , it will do the first object entirely and then come to the 2nd one.
There are times when this doesnt speed up cycles , most effective when you have big distances between objects. If you have multiple jobs across the table , often cluster is a lot faster and of course if you lasering the same thing on multiples , the worst you can lose is just one item if anything happens as each item is done independantly.
Im sure there are optimisation settings in the drivers as well , like full optimisation will work out the shortest paths as well as doing stuff like cutting inside circles out first.
Considering most ppl charge on a time basis , optimising run times means you can be either lower priced than a competitor or you can make more money in a day.

Rodne Gold
10-19-2006, 11:45 AM
Mike , what drawing would you like ? The tag we did? Or would you like a drawing using the various strategies with notes explaining why that was done?
Yes , we use the same method , multiple offsets.
We use the same method when doing thickish borders on rotary engraved plaques so we can do both that and finer text without changing bits.
As richard has noted , one might have overburns in corners and start/end points due to ramping problems , IE the laser slows down at corners but doesnt adjust its pulse rate accordingly and it overloads the material.

Jeff Chumbley
10-19-2006, 1:03 PM
George the link that you posted about the cherry wood takes me to your profile. I cannot remember which thread they were talking about the wood that was available.

Jeff

Mike Null
10-19-2006, 2:18 PM
Rodne:

Your answer will suffice. I was mostly interested in the borders as rastering them takes an enormous amount of time.

Thanks

George M. Perzel
10-19-2006, 3:10 PM
Hi Jeff;
Sorry-here's the link
http://www.sawmillcreek.org/showthread.php?t=44172
George

Jim A. Walters
10-19-2006, 9:27 PM
How do you rotate the starting and stopping points?

Jim