If you a cutting close to the material you need very good air assist or your will foul your lens with vaporized material. Not that I have ever used one, but looking into the CO2 lasers this is a common problem. They usually have air nozzles wrapped around the final lens.
Good point about the heat. Iām not as worried about the z axis stability, but the heat is worth considering, since both the laser and the driver have fans on them.
One reason I was thinking about mounting the driver near the laser was to reduce the number of wires that need to be routed to the tool head. Now that Iām looking at the wiring, though, I can see that there are some advantages to keeping the driver by the LCD (or at least away from the z axis tower) and running a bunch of wires to the tool - the main one being that when I swap out the laser with another tool, particularly an extruder head, Iām going to need to run a bunch of wires up there anyway.
I printed my remixed version of ductsoupās mount: http://www.thingiverse.com/thing:1245848, which has mounting points for the fan and line lasers, so I just need to put it all together and wire it up.
All told, thatās bad ass.
I didnāt bother drilling my Z and putting in the nut trap stuff because I used a mount that clamped on the outside of the pipes. Would require me to disassemble some stuff to drill those holes if I wanted to redo it for something like this.
But, it does give me some ideas to remix some sort of multi-tool holder that uses outside clamps instead of the Z nut trap. Though, Iād need to find a clamped tool holder to fit a 3d head just be able to then print a new design, which doesnāt make much sense. 
Iām thinking though, that it would be nice to have both a printer head AND laser on a single mount, with one of the tools just offset a little. I built a pretty big rig (some 24" x 36" or so)ā¦mostly for the laser to be able to engrave on 12"x24" sheets with some room to spare.
Iād likely never need that much room for a print head, so if it was offset and not able to use the ENTIRE area, that wouldnāt be a major problem. Iād likely not find a heated bed for the full size anyway, at least not in affordable form.
The reason Iām not all too interested in the interchangeable mount bit is precisely some issues like you said of wiring. Iād hate to have to constantly be unplugging wires and hiding the connectors out of the way to change tools. But having 2 tools on permanently, thatās just a little extra wire. I ran my laser wire up through one of the Z pipes anyway, so I have a second pipe to run wiring through if I donāt want to confuse anythingā¦
Now my brain is flooding with ideas that I donāt have the skill to do. Iām thinking of some sort of awesome āstackedā mount where the laser sits above a printer head, then can basically fold down on a hinged mount to be even height but offset of the printer when I need to use the laser.
Or maybe just printer in the front, laser in the rear? (that sounds more dirty than intended).
Iād have to measure available Z height on the back side of the axis to see if there would be enough clearance there pending how high Iād need Z travel to print.
ideas ideas ideasā¦
The multifunction head does sound interesting. I use or plan to use my MPCNC for routing, lasing, foam cutting (with recip needle), plotting, and 3d printing, so Iām trying to set it up for easy tool changes. Iām just starting down that road, though, so there will be plenty of bugs to work out. The laser is the second tool (after my router) that Iām trying to set up.
I agree what Karl did is awesome. What software did you use to blend the files? I would like a laser mount for universal set up. I am currently using the standard DW660 mount with my laser on a piece of plastic that uses the 4 clamp mounting holes.
Curt
Here is a quick blend I made using TinkerCAD. I am printing the universal mount now so I am not sure how well it will fit. http://www.thingiverse.com/thing:1250289
Curt
I used TinkerCad to blend the files. The universal mounts includes 3 different mounting pieces that you can use, depending on what youāre mounting. They can easily be joined to any mount you want. Be sure to leave enough clearance all around to slide into the receiver.
As I mentioned in the other thread, I had to spend some time with a swiss file and some acetone (for the ABS parts) to get everything to fit just right. Nothing unreasonable, though, and the resulting functionality is definitely worth the effort!
Let us know if you can come up with a good mount for the driver boardā¦I canāt come up with anything good yet
I took a look at the thing you mentioned - in thingiview, it looks like the two parts arenāt actually touching. They might stick together some, but they might not be very strong.
I wanted to make sure everyone knows Iām not taking credit for the universal mount - it was created by HicWic on thingiverse. Iām just telling folks about it and making some useful mounts, mostly made up of other peopleās mounts!
Karl
That was my first attempt at blending parts. Thanks for the heads up and I have since fixed it. In Thingiverse I linked to the original universal mount to show the remix and called out you and HicWic
Hey thanks for the callout. The new one looks much better, and the clearance for the slide looks good.
Karl
Here is an updated version of my mount. I also modified Karlās mount to remove the laser holders since I like his better!!. http://www.thingiverse.com/thing:1250531
Thanks, Curt!. My version of the laser mount has enlarged holders for the line lasers, but since you didnāt need those, the credit for the parts you kept should go to DuctSoup, who did the original design I used: http://www.thingiverse.com/thing:1025450.
I will. Iām thinking about some different designs. Iād like to incorporate all the control functions - LCD, laser driver, router speed control (Iām using the harbor freight one) - into one panel, if possible, with RJ45 connectors for the low power connections and some molex connectors for the high power ones (laser, extruder heater).
Hereās a question: to change the power output on the laser driver, you need to change some jumpers. I would like to be able to change the power easily with some toggle switches, or maybe a rotary switch. Anyone have any ideas for this? 4 toggle switches would give access to the 5 power levels (with the lowest power, .5w, being the default if all switches are off).
EDIT: It would actually take 5 switches, since there is no connection for the lowest level.
Along with the jumpers you need to adjust the pot to get the right voltage and they is set with the laser disconnected. I guess I do not see why you would need this. If you set up the laser at the max (recomended) setting then use the M106 Sxxx to adjust power with S255 being max power and S0 being off.
Thanks, Curt. So what youāre saying is that for my 2.8w laser, I should set the board to 2.5w output, turn the pot down and focus the laser for whatever my focal length will be, then turn the pot up, and just let the M106 command control the output over its full range from that point on. I shouldnāt have to change the jumpers or mess with the pot again unless I change focal length, right?
Makes sense to me. Does anyone know of a reason not to do it this way?
Thatās how I did it. Working so far, though I have to always fiddle because I change material size and Z height, which is why I think we all need a good spacer block that sets the Z exactly where we want it every time.
Sometimes I use a really low S number to test my focus and adjust Z height if necessary.
Yes, the jumpers and pot should not be adjusted unless something physical changes. Per the J Tech website they recommend that the laser be set up at a little over 2W to preserve the life of the diode. In the PicLaser and Laser Etch software the laser power is changed automagically via M106S.
I like the Jtech gear and their website but I think itās worth mentioning that there are much cheaper solutions available for laser add-ons. In the true āMost bang for least buckā spirit of the MPCNC you should consider building a laser add-on yourself. The Jtech laser is $350 and is a kit with 2.8w laser and the driver. After that you need the $20 fan upgrade and the $40 software package so itās a $400 project which rivals the cost of the entire MPCNC build. Take a look at DTR laser shop and youāll find the same 2.8w 9mm 445nm diodes mounted in a module with a 3-element lens for $70. Add another $20 for a heatsink and driver board and youāre in business. Free software options exist as well so you can do the whole thing for about $100.
Leo69
I get your point as I started down this same path but I very much doubt you will make anything near the quality and consistency as the JTech laser for $100. I am VERY happy with what I bought and I would not change it for anything. As far as the software I am sure there are free ones out there but I am not against supporting those who write software. Spending $30-40 for software is not the end of the world.
Here is what I burnt today using the Laser Etch software. The smaller one (2" wide) took 20 minutes and the larger one (4" wide) took 40 minutes. I am still working out the lasing speed vs/ laser power.
Curt
