Laser cutter for stainless steel stencils

[olkipukki]

The market is flooding with different sort of laser cutters and I wonder if somebody here own one to make in-house stencils.

What is price and operation cost starts from for a reasonable cutter and how easy to operate/maintain it?
Is it worth hassle rather than outsource to PCB house?

Thanks

[IconicPCB]

conventional CO2 laser will not touch stainless steel unless...

There is a surface treatment for stainlesss steel whihc will allow the CO2 laser to mark / cut stainless steel. The treatment is a spray pack of some black concoction. Itis sprayed on and when cutting completed it is removed.

Costs an arm and a leg.

A more apropriate laser source capable of cutting stainless steel is a fibre laser source..
A laser cut stencil cut locally in Brisbane willset you back at least a few hundred dollars. Owning and operating one.s own laser cutter might be economicaly viable under these costs. Asian sources will cut a stencil for a quarter of the price, With freight it works out at half the local cost. OK if planing in advance of a project, Otherwise local next day delivery may be essential.

[rx8pilot]

I have never seen a 'low cost' laser that can cut stainless sheet. It takes a lot of power, excellent optics, and a specific wavelength to accomplish that.

[olkipukki]

In Europe, a bit more than a week of waiting and you can get a spencil for $50, for extra 25/30% - just few days door-to-door

Any hint on a starting price for a decent cutter?

[IconicPCB]

30Wattfiber laser will cut stencil happily.
A 30 watt reasonable chinese fiber laser source a few thousand dollars.
On top of that optics and movement.

[IconicPCB]

See Raycus fiber laser.

[rx8pilot]

I have a 45W CO2 Epilog laser that won't touch metal. I can use Cermark to mark the metal but that is it.

[Fred27]

A hobby CO2 laser can cut mylar solder paste stencils. As rx8pilot states, it won't make any impact on metals.

[MagicSmoker]

The market is flooding with different sort of laser cutters and I wonder if somebody here own one to make in-house stencils.

Near infrared is supposed to be best for cutting stainless steel, so that means Nd:YAG and fiber lasers, which tend to be really expensive.

BUT... kapton (polyimide) and mylar (polyester) both make very good stencils that can be used 100+ times and which can be cut with a cheap 30-60W sealed-tube CO2 laser. Epilog is one popular manufacturer of lasers that are good for this application, but there are others.

That said, it probably isn't economical to cut your own stencils unless you are designing dozens of boards per year OR you are willing to pay a huge premium to get a stencil immediately, but since a stencil isn't worth much without a board, you would also need to have rapid board prototyping capability as well... All in all, it's probably best to get stencils made by, e.g., http://ohararp.com/stencils/ (no affiliation, just a satisfied customer of their kapton stencils).

[olkipukki]

What is mean "really expensive" - are we talking 6 digits (and plus) or...
as mentioned by @blueskull a cheapest starts from $15K, so $25-$30K will take us closer to a decent?

Actually, I never tried kapton and mylar stencils (basically, any non-stainless steel). Would be okay for 0402 parts and similar?
Not sure if I need this since $40-$50 will get me one from EU supplier (more or less as Chinese cost if include all taxes, risks, duties and shipping).

How difficult to use and maintain a cutter? Are there a lot of changes and overhead (setup type, gerber-to-what-ever-cutter-accepted-format converting) to fit into an existing workflow?
As today, I generate a fabrication output and send these to a PCB manufacturier(-ies).

[MagicSmoker]

...Actually, I never tried kapton and mylar stencils (basically, any non-stainless steel). Would be okay for 0402 parts and similar?

I've used kapton stencils for the initial prototypes of boards that had 0.65mm pitch QFP packages on them and the paste printed fine. I suspect going down to 0.5mm pitch would be risky, though. 0402 passives should be fine, too, but I never use anything smaller than 0603 so can't speak from experience.

[DerekG]

The market is flooding with different sort of laser cutters and I wonder if somebody here own one to make in-house stencils.

I'm not sure how many you need to make but PCBWAY will supply you panelised stainless steel stencils for about US$40ea.

[jpanhalt]

Why does it have to be laser?  Why does it have to be stainless steel (which alloy?)

I am always reluctant to make a suggestion when someone with a problem tries to define the solution -- assuming of course that there must be good reasons behind that.   Why not etch or reverse electroplate the metal template?   Have you considered copper or even (maybe better) nickel instead of SS?  After all, if etching gives you the resolution you need for the PCB, why won't it give sufficient resolution for the template?

John

[DerekG]

Why does it have to be laser?

It doesn't have to be laser cut, but the stencil shops are set up for this as it quick & accurate.

Why does it have to be stainless steel (which alloy?)

Stainless steel is generally used these days as it is very hard & lasts a long time. I actually prefer brass screens as they are easier to handle .......... but brass is not so common these days. Brass will still manage a few hundred thousand operations (if they are looked after) before they need replacing.

[IconicPCB]

I sometimes mill a stencil in double sided FR4 material ( 0.2mm thick ) as used in multilayer core production.
Would not use it on 0603 or finer pitch designs.

[DerekG]

I sometimes mill a stencil in double sided FR4 material ( 0.2mm thick ) as used in multilayer core production.

Yes, good thinking. We do most of our stencils in 0.2mm to ensure enough solder paste gets laid down on the board for reliability in automotive/vibration environments.

[mikeselectricstuff]

One possible route to low-cost metal stencils is photochemical etching - some commercial stencils are done this way.
You still have quite a lot of process optimisation to get it right though.

[awallin]

check this... plastic fantastic stencil with chinesium 40W co2 cutter

[richardlawson1489]

Here is a reference for you, which may help you to find the Laser cutter. http://hackaday.com/2015/04/03/cutting-smt-stencils-with-a-laser/

[D3f1ant]

So does anybody know what the cheapest laser machine is that will cut stainless stencils?

[Smallsmt]

I don't know if it's cheap but GCC has good quality machines.

Please look at
http://www.gccworld.com/goods.php?act=view&no=22

[Spikee]

Stainless steel stencils are soo cheap from china that seems crazy to invest in such machine.

~15-20 usd for ~30*30 frame-less stencil 0.1mm thickness (0402, BGA... all ok) , DHL/FEDEX/SF EXPRESS/EMS/Cheap china AIR  shipped within 36-72 hours.
With about 20USD shipping cost for DHL to most places. Can probably even do combine shipping if your pcb also come from china.

[D3f1ant]

It's not so much about the cost, its the time it takes to get a replacement when there is design flaws. 2 or 3 days is a very long time to have machine sitting idle.

[OSHStencils]

Thanks Blueskull, we do ship within 1 business day anywhere in the world and we utilize the best stencil cutting machine and metal on the market currently.

Our pricing is linear, and you only pay for what you need.  If you look on Twitter @OSHStencils you'll see lots of customer posted stencils, or our website in the gallery you will also see our product offerings.

[jmelson]

Yes, I make brass stencils form .003" brass shim stock, using the same technology for making PC boards.  I use Riston dry film resist, making a set of mirror-image artwork.  I glue the artwork in alignment, then slip the sensitized brass in between and expose and etch just like a PC board.
Works quite well.

Jon