Can I cut a PCB with the K40? Anyone have any experience with this?

Can I cut a PCB with the K40? Anyone have any experience with this?

I’m working on my LaserCam mod today & need to use sections of this PCB for my LEDs & resistors.

No, you can’t. FR4 is really nasty stuff, and it will just blacken. It’s best to just score with a knife and snap anyways, if I recall correctly.

@ThantiK Thanks for that ThanktiK. I wasn’t aware. I will do as you suggested.

If you get FR2 (paper based), it’s easier to score a PCB. Unfortunately, I haven’t found anything that does copper… if you have a UV/Blue laser, you can etch photo-resist. If you paint black, you can use a K40 to get rid of the paint and then use an etchant to do the pcb.

But copper doesn’t want to be cut. It reflects more than it absorbs of the 10um CO2 wavelength, and even if yo got it to absorb (eg, Fiber Laser with 1um), by the time it absorbs it, it conducts the heat rapidly away…

There is toutorials on YouTube on scoring PCB check it out if you are unsure

Thanks @Thor_Johnson & @Alex_Krause .

I’ve managed to score it with a simple Stanley knife & a ruler then snapped it. Not super straight edge, but doesn’t really matter. It’s just to hold 1 led & 1 resistor (for each of the 2 that I made) to make it easier to mount them where I want them going.

But, I’ll keep in mind what you mentioned for future if I ever want to etch photo-resist. & yeah, YouTube is always a great resource. Thanks again.

Dremel tool. I made some custom, tiny, single LED pieces a while back. The boards were 7x3 grids which I then cut into smaller pieces. Just watch your fingers.

@Ashley_M_Kirchner_No the problem with the dremel tool is that the dust is severely bad for you. Majorly bad for you.

Did you not notice the vacuum tube, which I specifically pointed out in the video as well?

@ThantiK Is the dust bad to breathe, or in other aspects as well.
@Ashley_M_Kirchner_No I noticed the vacuum & I think it’s a great idea to use the dremel like a table saw. Going to have to make a mount/bracket for my dremel to do similar. What would be even cooler is to make it literally like a table saw, where you can use a screen to push the pieces along & keep them running straight. Might have a go at something like that when I have some spare time.

PCB are typically made of fiber glass and can cause severe damage to your lungs

Yep, that glass dust is horrible. That’s why I have that vacuum nozzle so close, to suck up anything that blows off. I also use thin boards, 0.8mm. Standard thickness is 1.6mm, twice as much to cut through.

Does the vacuum have a filter with a small enough micron filter to keep from expelling dust from the exhaust ?

It has a few stages, yes. The last filter before air gets blown out is also a HEPA filter.

@Yuusuf_Sallahuddin_Y ​ the dust is very bad to breathe. If you don’t have a filter fine enough, it will also get blown out the exhaust and you’ll just end up breathing it anyways. This is exactly why I suggested the score and snap method. If you have a wet saw for PCBs, that’s fine too, as the fine particles never enter the air.

@ThantiK Thanks for that. I was wondering if the dust can enter via your skin too, or if a respirator would prevent the problems.

Hmm. What about mounting the dremel tool on the laser head then “cutting” with an appropriate bit and the beam off?

@Vince_Lee You think exactly like I do. I was just thinking about modifying the laser head to have an attachment for the dremel so I can use it to cut metal & other parts. Only thing I am wondering is how to make it raise up & down in between cut sections (else it will just continue cutting all the way to the next shape).

@Yuusuf_Sallahuddin_Y Offhand, I’m thinking of a dremel mounted on a hinged platform and having a solenoid that by default pushes the dremel sideways, tilting it up a bit in the process. Harbor Freight (dunno if you have those there) has a cheap and small dremel-type tool that might work perfect for this.

@Vince_Lee That’s awesome to hinge the dremel up. I have a dremel already with an extension to it, so I will not have to mount the heavy motor section on the head, just the extension cable thing (which is a lot lighter). Then I can suspend the motor section above. What I wonder however, is how do we control the solenoid to force it to lift & lower every time we finish one shape & need to go to the next shape? Any idea on that? or manually press a button?

edit: we don’t have a harbor freight to my knowledge here in Australia. But we have Bunnings & Masters (our biggest/best hardware shops, albeit a bit expensive prices though, just because they have a bit of a duopoly on the market).

wow that is super cheap. $10. I guess with conversion to aud, it would be more like $15-20, but still cheap compared to the $150 odd I paid for my dremel years ago.