Trouble with detail vector cutting through acrylic

[Mike Mackenzie]

This probably has a lot to do with there cutting capabilities.

Laser Equipment Specifications & Capabilities

Housed in a 4,800 square foot facility, Boston Lasers invests in equipment and technology to provide a full-service product line of laser cutting services to its clients. In 2004, it acquired the most accurate laser cutting tables in North America from Eurolaser of Germany.
Eurolaser merged a Synrad CO2 laser to the most accurate plotter in the world made by Zund of Switzerland. Boston Lasers then modified the equipment from a single use design structure to a fluid platform capable of accommodating a wide range of cutting needs. These modifications are the reasons Boston Lasers can optimally cut a variety of material. The modification process is part of the ongoing, mutual technology development between Eurolaser, Boston Lasers and our customers, which dates back to 1998.

Unique Boston Lasers capabilities include:

• Single operation Ink line marking and laser cutting while holding all tolerances
• Laser beam modification so that corners and cutting intersections do not burn out
• Projects are cut so that no S shaped corners are produced
• Offset any cut for the beam thickness to exact size object desired
• Laser pulse rates from 500 times per second to 20,000 times per second
• Capability to run an assist gas such as Argon
• Equipment downtime minimized because Boston Lasers are authorized field service engineers for Eurolaser and Zund in North America

Equipment specifications and capabilities

Boston Lasers operates four Eurolaser laser cutting tables, including a laser table that is the largest for hire in North America. All laser tables have optical registration.

Table cutting area sizes:

• 31”x 51”
• 47”x 51”
• 70”x98”

Laser wattage:

• 100 to 250

Specified point accuracy/repeatability

• +/- 0.001 inch
• Hold accuracy and sustain four G’s of stopping pressure without backlash and zero acceleration lag
• Repeatability is subject to modification based on client project needs

Laser beam kerf

• +/- 0.004 to 0.006 inch is typical
• +/- 0.0015 and up based on project requirements
• Cutting materials up to one-inch thickness
• Etching materials up to two inch thickness as a table and head clearance specification
• Laser beam kerf is subject to modification based on client project needs

Although you should be able to cut your attached design with this system what are your settings?

[Joel Matteson]

Thanks for all the suggestions and for taking the time to explain how to assign the different colors to the curves. I am confident we can put more effort into our design and tweak our settings and end up with a better end product. We will work on a couple of experimental files and take pictures of the result. If we are still having difficulties I will take the time to post the pictures and the cdr file to better explain our challenges. Thanks again!

JM

[Scott Shepherd]

Joel, it might also help to know all your settings. Speed, Power, PPI, Image Density would all help. Maybe there's something obvious in there that's being overlooked. Also let us know if the settings are for 1/8" or 1/4", and if what color the material is.

[John Johnson 2]

I think th answer is actually very simple. Dont't use 3mm Acrylic, use 1mm UHI, less power, less heat, less melting.

[David Rust]

I don't know how much help this is, but I cut out a heart made of little hearts a while ago and the 1/8" acrylic is pretty thinly cut.

Very nice Dee... was this for a necklace? I think it is awesome!

[Guy Hilliard]

Here's a little something I whipped up on my ULS X660 w 50watts, 2.0" lens, and air assist in 1 pass from 3mm (1/8") acrylic. The client thought that $12.00 apiece was a bit steep but I learned a lot from the experience. Lesson 1, when using the factory settings the manual focus tool is only "close" to being in focus, calibrating the focus tool to be "in focus" is a PITA exercise that is only useful for this specific case (small detailed cuts in acrylic).

[Kees Soeters]

One other thing to keep in mind: your cut-width.. When i cut in 2mm-acrylic with my 38mm lens, my cut is ~0.23mm wide. So when i want to cut a piece of 0.5mm thick there only remains ~0.25mm instead. I have to offset my vectors with 0.12mm and follow that vectors to get my 0.5mm.
So when your drawing is thin already there will not be much left..
together with splitting up the vectors and give it a change to cool, you mus be able to get pices of only 0.15mm thick..
I also think (my experience) that when you cut thin Acrylic sheet (<=1/8") you can better use a short-focal lens (1.5"). The DOF seems to be sufficient but you can cut faster.

Kees

[Ian Wilson (AUST)]

Looks amazing Dee!!

Is it rude to ask if you would share the file?

Regards,

Ian

[sanjay khan]

Hi everybody, it's great to get an opportunity to post a thread here since so many technical experts are available am pretty sure even my silliest doubts I would be able to clear.

At present I am facing issues with cutting acrylic font using laser.

I have attached the file for reference. The issue is it is getting burnt and we are not able to get this font due to which my jobs are all blocked.

Please do help me.

[Tony Lenkic]

Line weight is too high for laser cutting in attached file. You have to set it to 0.003 or less

Try attached PDF file

[Kev Williams]

Others have touched on this, but simply put, you may need to (a) make several passes, and you WILL need to (B) offset your cutting path to compensate for your laser beam width.

To end up with this "A" at 1/2" tall, you'll have to offset the cut path to compensate for the beam width.
In this example, I used the contour tool to offset the lines .003" outside, which equals .006" total, roughly the diameter of a typical 2" focused laser beam...





Below is my result, in 1/8" thick plex- Not the best, but it shows it can be done-
I originally tried this at 1/4" letter height, but the small detail- center of the A for example- was TOO small-
I ran this 5 times at 100 power 20 speed, which is roughly 20-30mm per second on my LS900, took about 70 seconds.
I could've increased the offset to .005", but may have lost the center of the A.. just need to experiment!
FWIW, this was my second try at 1/2", first try I went 4 passes and some places didn't cut thru.
Also, I used a pretty good shot of air...

[sanjay khan]

Hi all I appreciate all your valued suggestion and advice. Would definitely try to implement few of your suggestions and find out if it works. Thanks again to all the awesome members of this forum.