Best way to etch a PCB fast

[gv260ea]

Hi, I need to develop a pcb fast my design includes a pic24f some tracks are 13 mil thick and the clearance is 8mils. I have a cnc machine perhaps its a good time to use it. I have used toner transfer before but i never used it for a board like this.

[nctnico]

Get yourself a spray etching machine or build one yourself. With ferric chloride etching times are around 2 minutes. You can see the copper dissapear. I use UV sensitive boards BTW. I tried toner transfer >20 years ago but found it way too cumbersome.

[poorchava]

13mil width and 8 mil spacing is not something you can do with a common cnc mill.

Use photoresist, either presensitized boards or spray-on lacquer, print a mask on drafting paper (the half-translucent type) on laser printer, expose in tan tube, nail varnish hardener, under a strong halogene light (floodlight will do) or strong sunlight, develop in whatever is appropriate. 5-8g/liter of NaOH will work for most common photosensitive lacquers. Throw into a mix of 30% hydrochloric acid with any kind of peroxide (pharmacy-grade 3% one will do). PCB is ready.

[TacticalCode]

I haven't done any etching myself yet, but I think Photoresist looks promising. The fastest etchant seems to be HCl + H2O2 (Muratic acid + Hydrogen peroxide). Downside: That my produce Chlorine gas when etching... Be careful no the breathe in that stuff, it also oxidises surrounding metal surfaces, so you may want to do this outside.

Some links:
http://mad-science.wonderhowto.com/how-to/create-pcb-etchant-automatically-improves-after-each-use-0135192/
http://electronics.stackexchange.com/questions/5540/ferric-chloride-or-muriatic-acid-hydrogen-peroxide-for-etching
http://www.robotplatform.com/howto/pcb%20etching/pcb_etching_4.html
http://www.ladyada.net/library/pcb/inhouseetch.html

[praveen_khm]

Happy to see the links to etching. BTW, the reason I am happy is because I wrote the tutorials on Robotplatform and glad to see that listed in eevblog  O0

[Pariah_Zero]

You can also try laser printing & transfer for the resist, and gentle sponge action in place of spraying etchant. Read about 'direct etch' at pcbfx.com for the sponge method. Pcbfx also has their toner transfer products, but there are other good products for toner transfer. Some even use old color magazine photos, or dollar-store vinyl shelving paper.  I've used toner transfer quite a bit, and it works pretty well.

[orion242]

Watch the video on the last post here.

https://www.eevblog.com/forum/microcontrollers/pcb-engraved-what-do-you-think-about/15/

I have never seen copper etch that fast.