JTech Photonics 2.8W Laser Kit

So I will admit that I am new to the forum and fairly new to printing but i have done some and needed to share this.

I saw this 2.8W Laser Kit from JTech Photonics (http://jtechphotonics.com/) that fits on the Lulzbot Taz 5 and Mini and I wanted it. I currently have the TAZ 4 and it takes some adapting but the company was very helpful in making sure I was able to get it running and believe they will be posting new instructions to their site for the TAZ 4. I wanted to share it with everyone because the potential of 1 machine for printing and laser engraving/cutting for a hobbyist or small company is priceless.

Thank you Jay with JTech as well as all the staff at Lulzbot who has also been very helpful with my learning curve.

Russel

2.8W is very low for any kind of cutting. I have been hunting around for a laser cutter and am focusing on the Chinese 35W versions available on eBay (I know). If you are going to modify your TAZ or Mini, you may as well spend your time modifying the 34W version and get some oomph.

Thanks Russel for helping to get the modification of the Taz 4 complete including the new mount and sharing! The entire community thanks you! :smiley:

The laser in our kit is a diode laser, which is very easy to put on a 3D printer. I assume the Chinese lasers being discussed on Ebay are the ~40W CO2 lasers, which require water cooling, turning mirrors and special focusing lens that is large. It would not be advisable to put on a 3D printer. Much easier to build or buy a separate machine for it.

I agree the 2.8W is not as high power as the CO2 lasers, but you can’t compare them apples to apples. The wavelength of our diode laser is 445nm versus 10,600nm for the CO2 laser. This allows for the focus on the diode laser to be much smaller at ~0.006" (152um or the size of a human hair). With the smaller spot size you also have higher power density at the work surface than the CO2 laser. This puts the “cutting ability” closer together than you would think. It is kinda like saying that my car does 321 km/hr and your car only does 200 miles per hour. Your car must be slower! Of course it is not, you need just to convert into the same reference to do comparisons.

There are uses for both CO2 lasers and these smaller diode lasers. Benefits of the diode laser over the CO2 are:

  • No need for water cooling = no mess
    Less optics = no alignment issues
    smaller spot size = finer detail engravings
    instantaneous power changing = engrave greyscale pictures
    small package = fits on a 3D printer
    solid state device = 10,000 hours operation with no maininence

I would suggest for people who are interested in lasers to get both the diode kit and a CO2 laser. They both have things that they are better at and it doesn’t have to be just one or the other. Personally I like the idea of having a 3D printer that is also a laser engraver because you get two machines for just a little more of an investment. All of the electronics and motors are already done, just add the laser!

Anyway- you can check out the Lulzbot upgrade here: http://jtechphotonics.com/?page_id=2438

Regards,
Jay

So lets say I want to add one of these to my Taz. Do you sell any kind of “bolt up” laser shield module I can add to my Taz to ensure I don’t laser my eyeballs, and will the laser harm the bed if it hits the surface in between the holes in that metal printing grate?

I retrofitted one of Jay’s kits to my old Flashforge Printer. They work great for etching acrylic and some minor cutting. I have since upgraded to a 60w chinese laser machine so really no comparison. You’re not going to be doing anything fast with 2.8w, but it does open up some great possibilities. The issue i ran into was generating the gcode to work with the printer. I had to do a lot of manual code writing and editing to make things work. However, this was on sailfish, i believe marlin is better supported.

As far as protecting the bed, I would use a sheet of metal to protect it. The Borosilicate glass should not be damaged but the PEI very well could be. He does sell acrylic designed to protec you from reflections, and goggles also. The reflections are intense so be sure to be protected. These lasers are not invisible like CO2.

Safety always first with these lasers! Always use your goggles! We also sell a specially designed acrylic “laser shielding” that will block wavelengths under 500nm. It is not a product that is made very often by the manufacturer, so we buy it in larger sheets in their minimum quantity of 20 sheets. We then cut it to 12" x 12" and 24" x 12" and sell them on the site.
12" x 12" : http://jtechphotonics.com/?product=445nm-laser-shielding
24" x 12" : http://jtechphotonics.com/?product=445nm-laser-shielding-24-x-12

I also agree with discojohn to put a piece of aluminum that is painted matte black on the table. We got the one with holes in it just because that is what was available on two day shipping from amazon prime. :slight_smile: The aluminum is thick enough that the beam shouldn’t be focused on the PEI, but it is best to get a full piece without holes in it.

Printers running the sailfish firmware are not as easy of an upgrade as the Lulzbot with the Marlin firmware. Lack of support for G0 and other native functions in sailfish make it more difficult to generate G Code using common tools like we provide.

Yes, there are plenty of things you can do with both lasers. I am glad you got your CO2 laser discojohn. I am sure you are making some cool things with it!

Jay

If I had a laser on my taz, I would probably be cutting at a pretty set height I would imagine. You could probably print a holder with 4 small pieces of that plastic and make a magnetically attachable mini shield around the laser and the beam path that you could just pull off when not needed. Would be pretty easy to engineer.

Two other things to consider when retrofitting a laser are air supply to clear the kerf, and ventilation to remove the fumes. With an open design like the taz, a local ventilation source would need added, and a small compressor should be used to help with debris removal from the substrate being engraved.

Does anyone know of Linux software to engrave with a lulzbot mini? The various inkscape plugins, that everyone suggest, don’t burn away large areas (i.e. don’t take the laser spotsize into account). They just draw narrow lines where large areas are supposed to be.

The non-vector-based approaches seem to waste alot of time by rastering the image. Also the most suitable raster-based program, LaserEtch costs money.

Edit:
I wrote a python program img2ngvr to provide open software similar to LaserEtch.