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smholley
6 Posts |
 Posted - 24 Jul 2013 : 11:15:17
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In the past I have used an X Y Pen plotter to plot on film to make prota type boards using etch resist PCB. The plotter I have is rather past its best and pens seem less than easy to locate.
Does anybody on here successfully use a laser or ink jet to achieve the same. Peter advised it was possible with a Laser and drafting paper provided you printed on the correct side. However drafting paper seems to be a rare commodity. I need to buy a new printer of some sort so if anyone has any tips before I do so it would be greatly appreciated.
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Mike Warren
Australia
124 Posts |
Posted - 24 Jul 2013 : 11:30:48
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I regularly make single and double sided prototypes using Kinsten, which is a positive resist.
http://kinsten.co/pcb/ (I buy from Altronics in Australia)
I reliably get 10 thou tracks and spacing using a laser printer and standard transparency material. I have also used tracing paper, but the exposure time is about 1.5 times greater.
I print reversed so the toner is right against the photo resist.
I've been using Kinsten for about 10 years. Before that I used to use Riston and I find Kinsten cheaper, higher resolution, and easier to handle.
I'm happy to go into detail if you want.
http://mike-warren.net |
Edited by - Mike Warren on 24 Jul 2013 22:37:20 |
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smholley
6 Posts |
Posted - 24 Jul 2013 : 12:06:23
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| Thanks for the reply Mike. What sort of transparencies are you using ? I am weary of plastic ones in-case they melt in the printer |
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Iain Wilkie
United Kingdom
1015 Posts |
Posted - 24 Jul 2013 : 12:40:13
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If your in the uk, save yourself a lot of effort by using PCBTrain's express prototype service. This will give you a pth double sided board (no resist or screens) in a couple of days for a few quid.
Iain |
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edrees
United Kingdom
779 Posts |
Posted - 24 Jul 2013 : 13:39:42
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I've been using 3M CG3360 (clear) with an HP and two Brother laser printers which has given me excellent results (single and double sided) for many years, but I've now found "Black Diamond" OHP film on eBay at a fraction of the price of the 3M stuff and this works well too!
Bottom copper print normally (toner dust to photoresist), "top" copper print "mirrored" to ensure toner dust against photo resist again. If toner dust not in contact with photoresist you will get tracks with fuzzy edges.
Give the toner cartridge a good shake before printing ensures good & even print quality. Then 3 mins exposure in a small uv lightbox, although this is 60 seconds in my BIG uv lightbox.
"Double up" the transparencies to improve contrast, -use "targets" to align the two images then stick together with sellotape.
Don't buy expensive photo resist developer, a very small level (plastic) teaspoonful of caustic soda in 250ml tap water is just as good. ALWAYS add caustic to water, not the other way round.
10 thou tracks on Rapid Electronics photoresist FR4 board, - no problem!
If all else fails use PCBTrain, Eurocircuits or Spirit Circuits (latter provides free protos).
Best of luck. |
Edited by - edrees on 24 Jul 2013 13:41:28 |
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Iain Wilkie
United Kingdom
1015 Posts |
Posted - 24 Jul 2013 : 15:27:47
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Oh you do make it difficult for yourselves 
Iain |
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Mike Warren
Australia
124 Posts |
Posted - 24 Jul 2013 : 21:48:22
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quote:
Originally posted by smholley
Thanks for the reply Mike. What sort of transparencies are you using ? I am weary of plastic ones in-case they melt in the printer
I use plastic transparencies, but they are specifically labelled as for laser printers.
http://mike-warren.net |
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Mike Warren
Australia
124 Posts |
Posted - 24 Jul 2013 : 22:36:27
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quote:
Originally posted by Iain Wilkie
Oh you do make it difficult for yourselves
I wish there was a service like you have here, but is really nice to finish a layout before lunch and have a prototype on test by mid afternoon.
I also often need to do very simple one-off projects to solve particular problems. These could be done on strip board, but for the extra hour it's nice to have it on a single sided PCB with SM components.
Obviously, this is not practical for everything. In those cases I get a panel made in China. For just over $300 (double sided) I get a panel delivered in 7 days.
http://mike-warren.net |
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Mike Warren
Australia
124 Posts |
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Mike Warren
Australia
124 Posts |
Posted - 24 Jul 2013 : 23:23:12
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quote:
Originally posted by edrees
"Double up" the transparencies to improve contrast, -use "targets" to align the two images then stick together with sellotape.
I've never needed to do that with 4 different laser printers over the last 20 years. I do remember density being a problem when I was using Riston.
quote:
Don't buy expensive photo resist developer, a very small level (plastic) teaspoonful of caustic soda in 250ml tap water is just as good.
I tried that but found the development time (at least with Kinsten) is a lot less critical with the proper developer, and at $2 a packet (makes 1L) it wasn't worth the hassle.
Here's a board I made last week after I'd butchered it getting it fine tuned.
http://mike-warren.net/play/M20130725080807-web.jpg
Some of the tracks leading to the chip on the right are 8 thou.
I'm now awaiting a panel with 4 of the finalised (hopefully ) design (plus some other boards) that I can build up and field test.
http://mike-warren.net |
Edited by - Mike Warren on 24 Jul 2013 23:24:17 |
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smholley
6 Posts |
Posted - 29 Jul 2013 : 09:51:37
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Thanks for all your input, I will give it a try and report back.
Plainly a commercially made board is better for final production but it is nice to design something and have a working prototype in the same day. I also like the ability to find at least some of the errors in my design before paying for a proper board. |
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Topic |
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Printing or Plotting negatives for etch resist.