Outstanding! I just used your "Secret Sauce" to cut a stencil with a 5x5mm VQFN-48 (.25mm pads with a .5mm pitch), two SOP-8 .65mm pitch and a SSOP-28 with a .65mm pitch. I cut the stencil out of cheap transparency film, pasted up a board, placed the parts and baked. The board came out perfect! You're amazing. Six Stars!!!!!!
@@dholi2k I found that slow and low power works very well. It seems that it takes a significant amount of time for the laser to come up to full strength. We set out laser using percent power and speed. I found about 3% power and 5% speed gave excellent results. The laser now has a new tube so I will likely need to come up with new settings.
@@joed222 Thanks Joe. I've still to test on Transparency sheet, but tried on soaked paper using my K40 at 20mm/s but lines aren't straight. Will need to slow it down further I think.
that was genius. so smart. it just makes way more sense. i watched a few of these and everyone just plays off the idea of lower powerr high speed and engraving. you really came with a different angle with superior results!
This method works well. My cut time was more than 5 minutes so the water would evaporate. I switched out water for dish soap and got really good results.
Excellent experimenting. Great result on the final smd mask, especially around the pin slots. Thank you for your time preparing the clear video and explanation of your result. Brilliant work.
Very smart idea . I installed air assist on my cutter for a similar purpose. I haven't tried a stencil yet but plan to and it is nice to know there are other options to achieve a good job if the air assist doesn't cut it (pun)🙂.
I've seen a video somwhere about lasercutting stencils. What they did to not get any molten ridges around the edges was to not "cut" the design but to raster-engrave it. Cutting faster at higher power evaporated the plastic rather than just melting it through. Was on a bit of a higher end lasercutter tho. Might be worth a try if you haven't already?
Are the plastic fumes toxic? I am always worried what kind of materials I burn with my laser, like PVC plastics resulting in chlorine gas, ABS gets you cyanide, etc. What about air assist with cutting these stencils? Is overhead paper better than kapton/polymide?
Very good, what methods did you try that didn't work? I use masking tape to get cleaner cuts, particularly in timber and when I engrave acrylic, just wondering if it would be effective with OHP sheets. I look forward to seeing the mask in use.
Thanks. I tried different speeds and power on the bear film first. I didn't try with tape, but a few layers of dry paper, it helped but wasn't good. paper with water on one side was pretty good, but both sides worked a lot better. :)
NIce job! Show us the stencil in action? PS. How are the cut ridges now? Had a stencil made by OSH stencils, not too impressed, as with your proto, lots of ridges, kept getting small amounts of solder paste flowing under the stencil.
I've used 0.003" tape (~0.075 mm) with no issues and very good results, however any one with thinkness of 0.075-0.15 will do (I prefer 0.075 or 0.1 mm ones as it puts out just right amount of solder paste). It's not very expensive either (considering that you probably won't be using that much of it anyway). Just make sure you buy one without adhesive :) I use reflow oven (infamous Chinese T-962 with slight modifications) and work with a lot of very fine-pitch parts, any attempts to put on paste by hand ended up with a ton of bridges (some of which were under the chip so I had to rework it manually using hot air gun), so I gave up and now always use stencils.
@Chip Guy Vids Yea, I've put a crap ton of kapton tape just to make sure :) I've also reflashed MCU with community firmware, added MOSFET for fan control (so it's not that annoying anymore), and added cold junction sensor. Still I think buying that oven was the best ~$200 spent as it made assembling boards sooo much easier! Now I use 0402 passives everywhere I can 'cause they cost next to nothing ($10 for the full reel of 10000, which will be last for years for me) and help make my boards more compact. Hand soldering them would be a massive pain.
I'm thinking of doing a solder paste plotter instead of this route as I usually only make small number of PCBs but if you want to do more than 5-10 It's brilliant. One thing I would do instead though is buy poly-amide sheet instead of Mylar (projector film), a small cost difference and might just remove the need to use wet paper. It also is less transparent than Mylar making registration easier.
Great information. Thanks for sharing. Sooo.. with a higher power laser do you think stencil cutting is possible on your self built laser cutter/exposer/engraver?
Yeah in theory. I used about 7w of power and less could probably do if you go slower. The catch is, that it has to be a far infrared laser (the co2 is 10 um), else it will just shine straight through the film :)
i used only 20% power,and the Chinese specification of 40W is probably optimistic anyway :) I am pretty sure 5-10 W would be enough. Just be careful if it is a diode laser and not a CO2 tube, visible light lasers at that power are very dangerous to the eyes :)
I tried this once and failed. 40W is not enough and the only thing that really works is to engrave something into the solder mask or removing it. Or laser engrave something into a silk screen rectangle. The 10µm 40W laser can not cut the copper, it's too reflective. Cutting the PCB is theoretically possible but a stinky firey process that leaves black burned awful looking edges.
Outstanding! I just used your "Secret Sauce" to cut a stencil with a
5x5mm VQFN-48 (.25mm pads with a .5mm pitch), two SOP-8 .65mm pitch and
a SSOP-28 with a .65mm pitch. I cut the stencil out of cheap
transparency film, pasted up a board, placed the parts and baked. The
board came out perfect! You're amazing. Six Stars!!!!!!
What speed did you use for vector cut using this method and what mA did you set the laser to?
@@dholi2k I found that slow and low power works very well. It seems that it takes a significant amount of time for the laser to come up to full strength. We set out laser using percent power and speed. I found about 3% power and 5% speed gave excellent results. The laser now has a new tube so I will likely need to come up with new settings.
@@joed222 Thanks Joe. I've still to test on Transparency sheet, but tried on soaked paper using my K40 at 20mm/s but lines aren't straight. Will need to slow it down further I think.
@@dholi2k I do my work at Gainesville Hackerspace. We have a K40 and a VLS3.50. I cut the stencils on the VLS.
0.5mm pitch is very challenging. Great results. Thanks for sharing.
Brilliant idea with the wet paper, thanks a lot for sharing such accurate results! Keep up good work sir.
Great result, much thanks for sharing. Excellent use of lateral thinking!
that was genius. so smart. it just makes way more sense. i watched a few of these and everyone just plays off the idea of lower powerr high speed and engraving. you really came with a different angle with superior results!
This method works well. My cut time was more than 5 minutes so the water would evaporate. I switched out water for dish soap and got really good results.
Excellent experimenting. Great result on the final smd mask, especially around the pin slots. Thank you for your time preparing the clear video and explanation of your result. Brilliant work.
A massive THUMBS UP from me, thank you. Merry Christmas 👍😷👍
I honestly doubted it could be done... when I get my cnc/laser put back together I’ll have to give this a go, thanks.
Very smart idea . I installed air assist on my cutter for a similar purpose. I haven't tried a stencil yet but plan to and it is nice to know there are other options to achieve a good job if the air assist doesn't cut it (pun)🙂.
I just made a video about soldering with a k40! Hadn't thought about smd stencils, nice job dude
Very cool thinking, this should do the trick for what i am looking for, thank you very much!
Thank You! Just what I was having trouble with....
Switch to a 38.1mm/1.5" focal lens for finer kerf.
very interesting thanks - i want to cut air brush stencils - what would be the minimum power required for a cnc laser cutter? thanks
Thank you for sharing ! I am going to try this first thing tomorrow.
Impressive work EC
Great tutorial and great solution. Thanks very much. Nice job.
Have you tried adding air assist and beefier ventilation to the laser since the video was made?
Impressive work, congrats.
Could it be possible to cut for example a soda can plate? 0,1 mm thickness
Any ideas for trying this with a 5.5W output diode laser? Maybe spraypaint the transparancy with a fine coat of black and then try it?
you did nice job, thanks for nice idea i was facing this problem my self ill try this way self soon. Thank you one more.
I've seen a video somwhere about lasercutting stencils. What they did to not get any molten ridges around the edges was to not "cut" the design but to raster-engrave it. Cutting faster at higher power evaporated the plastic rather than just melting it through. Was on a bit of a higher end lasercutter tho. Might be worth a try if you haven't already?
I tried it, didn't really work in my machine :)
Nice to know! So i won't bother trying it myself, since i've got pretty much the same one as you do
There used to be special transparent film to handle the heat in regular laser printers but I guess that's what you used?
yeah, they are for laser printers :)
Thank you!!!! I will have to try this!
Amazing tricks. many thanks!
Very good results! Nice!
Are the plastic fumes toxic? I am always worried what kind of materials I burn with my laser, like PVC plastics resulting in chlorine gas, ABS gets you cyanide, etc. What about air assist with cutting these stencils? Is overhead paper better than kapton/polymide?
Very nice and easy :)
If only I could afford a laser cutter :D
Very goog trick !
Thanks for sharing ! 👍👍👍
Thanks
Realy you saved me man thnx
excellent presentation-- thanks.. Watching at 6:25, you don't have an exhaust fan???
yes, but I realized all the outlets were in use, when I were about to turn it on :)
Which material is that plastic sheet?
Will it cut aluminum?
thats an awesome trick!
Thank you!!!
Have you tried QFN or any other package with 0.5 mm pitch? How is the cutting quality for that?
Very good, what methods did you try that didn't work? I use masking tape to get cleaner cuts, particularly in timber and when I engrave acrylic, just wondering if it would be effective with OHP sheets. I look forward to seeing the mask in use.
Thanks. I tried different speeds and power on the bear film first. I didn't try with tape, but a few layers of dry paper, it helped but wasn't good. paper with water on one side was pretty good, but both sides worked a lot better. :)
NIce job! Show us the stencil in action?
PS. How are the cut ridges now? Had a stencil made by OSH stencils, not too impressed, as with your proto, lots of ridges, kept getting small amounts of solder paste flowing under the stencil.
I don't have the boards yet :P Thanks
Ok, looking forward to next video, missed the bit about no raised edges :)
really nice ! Thank you
Very low tech! Love it. Would not have thought to use water!
Thanks :)
wow, very cool
Thanks!
Thank you
You might want to try using kapton tape - it's a lot stronger so small bridges not break easily
The tape I have is too thin, so it won't leave enough paste. :)
I've used 0.003" tape (~0.075 mm) with no issues and very good results, however any one with thinkness of 0.075-0.15 will do (I prefer 0.075 or 0.1 mm ones as it puts out just right amount of solder paste). It's not very expensive either (considering that you probably won't be using that much of it anyway). Just make sure you buy one without adhesive :) I use reflow oven (infamous Chinese T-962 with slight modifications) and work with a lot of very fine-pitch parts, any attempts to put on paste by hand ended up with a ton of bridges (some of which were under the chip so I had to rework it manually using hot air gun), so I gave up and now always use stencils.
I use 0.1mm kapton foil. Works fine.
Let me guess: One of your T-962 mods was to take all that stinky white adhesive tape off the insulation and replace it with kapton tape :)
@Chip Guy Vids Yea, I've put a crap ton of kapton tape just to make sure :) I've also reflashed MCU with community firmware, added MOSFET for fan control (so it's not that annoying anymore), and added cold junction sensor.
Still I think buying that oven was the best ~$200 spent as it made assembling boards sooo much easier! Now I use 0402 passives everywhere I can 'cause they cost next to nothing ($10 for the full reel of 10000, which will be last for years for me) and help make my boards more compact. Hand soldering them would be a massive pain.
I'm thinking of doing a solder paste plotter instead of this route as I usually only make small number of PCBs but if you want to do more than 5-10 It's brilliant. One thing I would do instead though is buy poly-amide sheet instead of Mylar (projector film), a small cost difference and might just remove the need to use wet paper. It also is less transparent than Mylar making registration easier.
Hi EC, is that mylar or what type of film is that you did your laser stencil on?
do you have a fan or compressor on the cutter?
Great information. Thanks for sharing. Sooo.. with a higher power laser do you think stencil cutting is possible on your self built laser cutter/exposer/engraver?
Yeah in theory. I used about 7w of power and less could probably do if you go slower. The catch is, that it has to be a far infrared laser (the co2 is 10 um), else it will just shine straight through the film :)
Going to try this on my K40. Can you tell me what settings you used on your K40 for this?
I haven't tried it on our K40,
what software do you use to convert a gerber file into a pdf? great video
Can it do QFN size stencils?
Very nice idea ! I am going to try this.
A question : do I realy need a 40W laser ? What can be the minimum for this you think ?
i used only 20% power,and the Chinese specification of 40W is probably
optimistic anyway :)
I am pretty sure 5-10 W would be enough. Just be careful if it is a diode
laser and not a CO2 tube, visible light lasers at that power are very
dangerous to the eyes :)
and invisible also, I mean light that could enter the eye
What wattage tube do you have in the cutter? Thanks for the videos :)
It is a 40 tube :) Thanks for watching!
does a 2.5w laser work ?
Thank uuu
amazing!
bravo!
Have you tried laser etching a PCB?
I tried this once and failed. 40W is not enough and the only thing that really works is to engrave something into the solder mask or removing it. Or laser engrave something into a silk screen rectangle. The 10µm 40W laser can not cut the copper, it's too reflective. Cutting the PCB is theoretically possible but a stinky firey process that leaves black burned awful looking edges.
Check out his channel, he built a laser engraver specifically for this purpose
What will you use this for ?
I need to make a few boards, so I want a stencil for applying solder paste, instead of soldering each component by hand :)
Nice :D
Thank you!