(Part 2) Top products from r/ChineseLaserCutters

I got the mini k40 (would not do that again). It works great, but I didn't know it at the time that I would be getting a weaker laser. I was about a week too late learning about tube sizes being the better way to know the true wattage.

I have done a series of upgrades and then re-dos. So hopefully you can learn a few things from all my tinkering.

Analog Milliamp Meter

I bought this meter. I followed this link for the install.

Exhaust

I initially went with an inline 3" bilge pump that had a corresponding 3d printed exhaust mount. It was ok, but in the end I just wasn't good enough when I started cutting more leather/wood.

So I went a little overboard, but I am glad I did. I went with this blower instead. I made my own 3D printed mount for it. I printed 2 adapters for the blower to fit 4" ducting and then routed it up and outside my garage.

I also removed the small internal duct thing prior to installing the new exhaust. it gives me a little more cutting room as well.


Air Assist

I went with the Light to Object head and bought a new lens to fit it.


Drag Chain

I bought a 10x10 drag chain off amazon. I had originally printed one, it was ok, but I recently switched up the mounting of the drag chain to run along the X gantry which gave me a little more room to cut.


Laser Aim Assist

I made a mash of 2 different thingverse designs to hold 2 red line lasers and where they intersect is my laser beam. It works well, I made it this way originally when I had an adjustable table. Honestly, now I should switch back to a single red dot, but I am too lazy. The two lines will sometimes move on me so I end up having to do a test fire every so often to ensure they are lined up properly.


Spring Loaded Adjustable Bed

I followed this guide


Hopefully this helps you out a bit.

Yep! I use this one. I considered the one you linked, but got the metal one simply because it was cheaper at the time. Both would get the job done.


I have it connected to my k40 via 4" dryer hose and this flange hose fitting which fits perfectly in the slot on the back of the k40.


Used these clamps to secure the dryer tubing together.


As far as how well it works, I'm pretty satisfied. I have the exhaust blowing out a 4" fitting attached to a board I close in my window. I smell a little bit of burnt wood when cutting, but it's very minute. Almost all smoke goes out the window. The suction is very good, if I'm cutting card stock it occasionally sucks the small paper pieces right off the cutting bed. When I'm doing laser alignments, it almost completely eliminates the smell of burning masking tape during test firing even with the door open.

I got the same pump. Works great. I never could find that fitting at a hardware store. Just ordered it. I have it rigged up with some fittings that don't fit and lots of Teflon tape and covered in epoxy. Good seal, but yeah, I'm down to change that up.

Oh yeah, for the OP, while you are getting your water setup. I'd suggest grabbing one of these flow indicators. Seems so expensive for what it is, but also get simplicity to know your water is flowing (and also to gauge roughly how well it is flowing).

Even expensive and quiet aquarium pumps are nowhere near the lpm/gph of the one linked above. My laser-cutter's air pump is a 1100 gph one which translates to 70 lpm.

The top-of-the-line, and far quieter, Whisper-300 from Tetra produces about 10 lpm, I have 4 of them on my 600-gallon aquarium... I tried several air-pumps before choosing the Tetra for its quietness (the laser is in the garage, I don't care about the noise. The aquarium is in the living-room wall. I do care about noise there :)

Now, whether you need more than a Whisper-300 can deliver, I don't know. My limited understanding is that the better the air delivery, the better you can do deep cuts, up until the air-delivery is producing a detrimental cooling effect. That's why I went big, and put a valve on it to adjust the pressure.

At the moment, I'm letting the air go full-blast. I'll start characterising the laser when my macken-knock-off power-meter arrives and part of that is going to be air-assist effects.

Which pump did u get? I use this Tetra Whisper Easy to Use Air Pump for Aquariums (Non-UL) https://www.amazon.com/dp/B0009YJ4N6/ref=cm_sw_r_cp_api_i_jaYlDbMBEJQNF , with a 3d printed nozzle and works great

I have this one, but I got it when I was using the nozzle style air assist, so I think it is more powerful than I need with the tubing. It is also kind of loud, I only turn it on when cutting. I use silicone tubing, the same as used on the water cooling, to bring the air to the laser head. Using a drag chain to support it.

I used this one:
https://www.amazon.com/gp/aw/d/B01M7S46YZ?psc=1&ref=yo_pop_mb_pd_title

Along with a 3d printed duct for the back at the machine, with the blower positioned at the end of the hose. Works great.

Yes I have gotten it. Replaced the exhaust components straight away and added 3d printed air assist was about to try it out and saw the focusing lense was crushed. Seller seems like he's going to replace it I did go ahead an order a new one already and head with air assist built in. Waiting on those to arrive so I can fire it up and give it a try.

TEN-HIGH Diameter 18mm Focal Lens for CO2 Laser Cutting engraving machine, FL: 2" (2"/50.8mm) https://www.amazon.com/dp/B01ER2ISX2/ref=cm_sw_r_cp_apa_i_hqeEDb7ZZZSMS

18mm Laser Head w/Air Assisted. Ideal for K40 Machine https://www.amazon.com/dp/B0094WLPYK/ref=cm_sw_r_cp_apa_i_5peEDb2HHPVBS

You could use that along with some aluminum tape to seal it to the back of the cutter.

I use this blower:
attwood Quiet Blower Water Resistant (White, 4-Inch) https://www.amazon.com/dp/B003EX02DA/ref=cm_sw_r_cp_api_3L18BbTB6G1FB

Along with this vent hose:
White Flexible Pvc Vinyl Vent Duct Hose, 4 in. x 20 ft. https://www.amazon.com/dp/B01G198P5A/ref=cm_sw_r_cp_api_4R18BbNJ19ANP

These clamps:
Cambridge Tension Clamps, 2 Pk, Zinc Plated Steel https://www.amazon.com/dp/B07737XRRH/ref=cm_sw_r_cp_api_SS18Bb12827MZ

And this quick disconnect:
Dryer Dock Dryer Vent 6" for 4" Tubes, White https://www.amazon.com/dp/B0028BAAWW/ref=cm_sw_r_cp_api_4T18BbV6CJ1TW

If you put the blower near the window it will keep negative pressure upstream which helps put less smoke into the room.

I don’t exhaust out a window, but something like this might do the trick for you:
Window Dryer Vent (Adjusts 24 Inch Through 36 Inch) by Vent Works https://www.amazon.com/dp/B01M17V4CO/ref=cm_sw_r_cp_api_AW18BbDW0592D
Though there may be cheaper or better DIY options for that part.

Was looking at one of these fans that I saw on this post (I like the 3D printed adapter). How did you connect the 12v to the system? Or did you just add a power inverter?

Any 10600nm CO2 Laser Safety glasses/goggles will work.

https://www.amazon.com/Laser-Safety-Eyewear-Excimer-Wrap-Around/dp/B000HJMS5E/

Sorry, got my units wrong... Gph is what I was thinking. I have this one and it works well!

VIVOSUN Air Pump 950 GPH 32W 60L/min 6 Outlet Commercial Air Pump for Aquarium and Hydroponic Systems (32 W) https://www.amazon.com/dp/B06XDKRYC6/ref=cm_sw_r_cp_apa_tCxHAbN4MTBPN