[JDTech]

Hi Guys, Has anyone had any experience with the laser modules from KALE CNC.
808nm modules available at 1W, 2W,3W and 5W power and with TTL control.

They advertise on ebay etc but thier web site is pretty poor with very little information.

I have a fairly decent CNC router (~6K worth) turning up soon for the prototyping workshop and would like to try laser engraving/marking some plastic switch buttons and might also investigate laser cutting thin material, card, plastic etc. I much prefer to the idea of a bolt on module rather than fitting a laser tube and guide mirrors assembly so that its quick to fit/remove.

So, any experiance with the KALE products or alternative laser modules?
Thanks, John.

[HorridHenry]

If you do import one of these lasers....have the seller mark the import doc as "machine parts",otherwise you might find customs stopping it coming through to the UK.

Forget the 1w/2w and buy a minimium of 3w or more.

[JDTech]

Yep, I think the high power 3W or 5W would be the minimum unless Im happy to work very slowly.
So I've been doing a bit more back ground reading, as I want to understand better something I may buy.
My shaky understanding is this.

For engraving I want to heat and ablate the surface OR heat and modify/distrupt the surface/sub-surface of a material to leave a noticeable mark.
For Cutting I want to heat sufficiently to melt/burn/vaporise my way through a material.

When Laser light hits a material, it can be reflected, adsorbed or pass through it. The frequency of the laser light and the properties of the material will effect the percentage split between these effects. To engrave or cut effectively you need the material to absorb as much of the laser light energy as possible and thus heat up.
So black items would cut better than white items, assuming the same material.

CO2 type lasers are effective since they typically operate at longer wavelengths (5000nm - 12000nm), to which most materials are opaque and readily absorb these frequencies.

The KALE module is based around a Laser diode and has a wavelength of 808nm (this is just in the IR range, with visible light roughly between 400 and 700nm), it thus has a much shorter wavelength than a typical CO2 laser and many materials (such as plastics) are far less opaque and not as much of the energy will be absorbed by the material.

By using a high power laser (say a Kale 5W) I can push more energy into/through the material even though the same percentage of the total energy emitted, is absorbed by the material.

So the KALE 808nm units may not be very good with quite a few plastics, especially clear acrylics etc.
That having been said, the KALE units are low cost, compact and look simple to fit and operate. If it was just that they would be slow, then it might still be worth trying. I really need to find out the relative abortion of the materials I want to play with.. hmmm.

[pontiacg5]

May I suggest buying a weaker 808nm module, possibly around 300mW?

They are relatively cheap on ebay, easy to power (usually 2AA batteries is sufficient) and easy to focus. You could then use the laser module to attempt to mark the materials you want to cut/engrave to judge how they will cut.

Be extremely careful though. One advantage of a CO2 laser is that the cornea is completely opaque to the CO2 wavelength. 808nm is a different story, the cornea is completely transparent to this wavelength. Your eye will focus the 808nm light on your retina, so it takes a LOT less power to do permanent damage. Just looking at an 808nm "spot" while cutting may very well be enough to do irreversible damage. You WILL need special 808nm blocking glasses! Don't try to use just anything as you can with a CO2 laser.

I also suggest you check into using a 445nm laser diode. More materials (like white paper, for example) absorb the 445nm wavelength than 808nm. 445nm modules 1W and up are pretty cheap, and it is possible to combine several into one cutting point. (using a process called "knife edging" or a polarized beam splitting cube, depending on how many you have to combine.)

Don't expect to cut much of anything with any thickness to it though. When you get going that slow with a laser cutter it just burns stuff instead of cutting. You will still be working extremely slowly, even with 5W of power and a material that readily absorbs 808/445!

[SotChrys]

I buy from KALE CNC a 12 Watt Laser with Laser Driver for 1000$
I test it manualy and works fine with several materials wood plastic, foam.
I buy it to fit it on my DIY wooden cnc and now searching how setup to use it with Mach3
(laser On/Off)

[JDTech]

Hmm, Thanks Pontiacg5,
Good point, find out how 808nm works on samples, then if it seems to be effective but just slow; then go to a higher power unit and increase speed or PWM the unit to modulate the power.
I'll also have a look at the 445nm as well.
Appreciate what you say on the safety side, I've been looking at the various laser protective glasses available. I'm suitably paranoid with protecting both my sight and hearing round the workshop but when dealing with a new technology its good to be forwarded.
Cheers, John.

[vizardknight]

I have the 3 Watt Kale 808nm laser module.
It cuts paper pretty easy...the piece I tried was a tan colored piece of construction paper.
When properly focused and speed was perfect it sliced thru the paper without making any burned edges.
Looked just like it was cut with a razor blade.

While burning thru plywood (1/16") and while cutting the construction paper I looked at the spot it was cutting for very brief 1 second at a time with no ill effect.
I got this laser second hand with an old Shapeoko CNC and really knew nothing about laser wavelengths and how bad some of these even low powered lasers can
be to a persons eye sight!!

I have rebuild the Shapeoko2 from ground up to a full blown 1000mmx10000 Xcarve on steroids. 2.25HP router for spindle and all stiffening mods have been done.
Next up is 80-100 Watt CO2 cutting laser upgrade which is going to take a long time to implement. While I am working on the infrastructure to support 26,000 volts, water, air and 100 watts of shear terror
running around my XYZ axis's (Axi? lol)...My plan is to experiment with the Kale 808nm on as many different materials and setups as possible. If they is any interest in this thread, I will gladly post my results as
I have too found very little real useful examples of what a 3 Watt 808 can do.