Woodworking Laser

[pjblues]

When I was at the Aspire camp a couple of years ago, some of you were using lasers for engraving and cutting versus cnc routers. Now that I have a couple of years experience with routers, I am interested in lasers. I am a home hobby person, not a production shop so I would assume, there are top quality lasers for people like me? What are the preferred brands of lasers being used for processing wood and acrylic? Secondly, I cannot remember, but, I assume, lasers can be used for 3D work? Lastly, is processing with lasers faster than cnc?

Thanks.

[pjblues]

Sorry, I did not pay attention, there was another posting on lasers. I have read through the postings and see the big three. However, that said, for cutting 1/2" hard wood, what wattage of laser would I need?

Thanks.

[dhellew2]

Pjblues,
1/2" cutting wood, 120 watt is probably the minimum
No, you cannot do 3d carving with a laser
Yes, you can do some nice engraving that is a slight 2.5d
For what they do, lasers are faster than cnc
Some projects are better when using both machines such as lithophanes [cnc] with text [laser]
Dale

[Rcnewcomb]

No, you cannot do 3d carving with a laser

That is no longer true depending on your definition of 3D. Some of the lasers can do 2.5D/3D work using grayscale 3D models. Kern Lasers is one of the companies demonstrating this. Epilog shows samples as well. Gantry Company sells 3D grayscale artwork.

[GeneMpls]

I have the Kern samples (they are located in Central Mn- my home town- Wadena) and they are truly awe inspiring. It takes a very specialized bitmap to do these files. I have a 130w CO2 laser (Chinese) and have not tried hardwood, but it will cut .5 corian and .75 acrylic. Gene

[pjblues]

Great information folks. Thanks so much. I thought a laser over 100 watts would provide the best results and speed.

[mtylerfl]

I have the Kern samples (they are located in Central Mn- my home town- Wadena) and they are truly awe inspiring. It takes a very specialized bitmap to do these files. I have a 130w CO2 laser (Chinese) and have not tried hardwood, but it will cut .5 corian and .75 acrylic. Gene

Hi Gene,

You stated "It takes a very specialized bitmap to do these files."

Can you be more specific about this? I always thought any non-compressed high-quality greyscale bitmap of a 3D model would faithfully render regardless of whether it is done with a laser or CNC. Z-height is represented by 256 shades of grey (0-255) typically. I am very curious what is particularly special about these greyscale bitmaps you are referring to.

Thanks in advance for any details you can share.

[JamesB]

FYI if your looking to test any lasers that have this functionality you can export the composite 3D model from Aspire by using the Model drop down menu from the top of the interface and picking "Export as Greyscale Bitmap". There are 5 output options - jpeg, bitmap, tiff and png which I believe will each give you 256 levels of gray to represent the Z range. Then the last one is 16-bit Tiff which will give you a much smoother set of grays (and is the best option if trying to use this for outputting a 3D grayscale map for other software) - not sure if there are lasers supporting this option but if they do in theory it would give you the best results.

NB. You often want to have a background of white in a laser cut image that will represent the top of the material. To achieve this in Aspire you'd need to add a Zero Plane and then effectively sit the model down into the material by applying a negative base-height. IF you just work with a raised model the background will be black and most lasers will then try and cut that full depth...

Cheers,
James

[mfirlott]

Additional info. Just to be clear as instructed above...3D model exports=yes, 2D images=No. For others reading this thread...for images, it is not as simple as just using "any image" you may have and converting that to gray scale. Some softwares do this...like Aspire...but that only works on a 3D model export, not a bitmap. I have both Corel and Adobe and these advanced tools cannot do this as a 2D image does not have the Z height info in the file like a 3D model does. What is needed is a bump or height map and that's a very complex requirement that I have not been able to resolve with these tools. When I need bump/height maps, I purchase them.

[TReischl]

MFirr:

Before Aspire existed, I used Corel to create bitmaps that could be used in the photo engraving software.

It is totally possible to create 3D images in Corel. This one was created with the Blend tool:

Interestingly, I saved it as a 32 bit color TIF file and it worked better than the greyscale options. ::::shrug:::::

[mtylerfl]

Hi Ted,

Color bitmaps are automatically converted to greyscale(when used for 3D relief applications), even though "we humans" still see it as color.

[GeneMpls]

Russ at Sarbar Multimedia has done some 3D experiments posted here:

[pjblues]

Wow, this is absoulte great information, especially for a guy like me. I just thought you purchased a laser and scanned in an image and lasered it.

[mfirlott]

TReischl:

I know Corel and Adobe can do wonders...it's just me who can't.