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General => Open Discussion => Topic started by: Ettore_M on November 24, 2013, 11:17:17 AM

Title: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 24, 2013, 11:17:17 AM
Ι decided to start using the photosensitive method, because I don't have a laser printer. Now, I print inkjet transparencies and I use them to sensitise the board. Yesterday, I etched a Cave Dweller and I had the best results. The little letters ("MBP", "CAVE1") came out with great detail! I'm amazed.

I haven't seen anyone of you guys using photosensitive boards for etching. Most of you seem to prefer the usual toner transfer method.

Why is that?

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: stevie1556 on November 24, 2013, 12:33:59 PM
I never get good results with PNP blue, and that put me off trying other methods like photo or magazine paper. In the end I always used photo boards, always had great results with them and I recommend it for home etching.

Shameless plug - I'm selling a UV light box and heated bubble etch tank!

Sent from my thumbs using Tapatalk!

Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 24, 2013, 12:38:14 PM
Quote from: stevie1556 on November 24, 2013, 12:33:59 PM
I never get good results with PNP blue, and that put me off trying other methods like photo or magazine paper. In the end I always used photo boards, always had great results with them and I recommend it for home etching.

Shameless plug - I'm selling a UV light box and heated bubble etch tank!

Sent from my thumbs using Tapatalk!\
I would be into the UV box, but I just ordered 200 UV LEDs to make one myself. ;)

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: croquet hoop on November 24, 2013, 01:34:07 PM
Someone linked this article (http://quinndunki.com/blondihacks/?p=835) some time ago and I found the photo method very interesting, mainly because you don't have to mess with toner, proper pressure with the iron, etc. I have not gotten around to making my own PCBs yet (I just send them off to OSH Park), but if I had to do it, I would try the photo method first.
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 24, 2013, 02:06:09 PM
It's indeed very interesting! And it's really easy to get great results. I got great results on the first time!  :D
And I think that it will be easy to make double-sided PCBs too. I bought a double-sided board, so I'm gonna try it soon.

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: stevie1556 on November 24, 2013, 02:39:56 PM
Quote from: Ettore_M on November 24, 2013, 12:38:14 PM
I would be into the UV box, but I just ordered 200 UV LEDs to make one myself. ;)

Hector

I've built 3 in the past, 2 of them didn't work as the wavelength on the UV LEDs was wrong. I can't remember what wavelength you need off the top of my head. Also, build it using stripboard (vero) as it will make it stupidly quick and easy!

Sent from my thumbs using Tapatalk!

Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 24, 2013, 03:13:35 PM
Quote from: stevie1556 on November 24, 2013, 02:39:56 PM

I've built 3 in the past, 2 of them didn't work as the wavelength on the UV LEDs was wrong. I can't remember what wavelength you need off the top of my head. Also, build it using stripboard (vero) as it will make it stupidly quick and easy!

Sent from my thumbs using Tapatalk!
Nice! :) I'm going to build one, using this tutorial!
http://www.carlolog.net/log/2012/09/making-an-uv-exposure-box-from-scratch/ (http://www.carlolog.net/log/2012/09/making-an-uv-exposure-box-from-scratch/)
Possibly, without the uC board!

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: rullywowr on November 24, 2013, 04:02:15 PM
"I don't always etch myself, but when I do...." I am of the old school and when I etch just use some glossy photo paper or blue toner transfer paper with a laser printer.  I know if you don't have a laser printer you can go to staples or any copy shop and you can copy/print your design on the paper of your choosing.

While the photo-resist method comes out great, I think what puts people off from using it is the fact you need to buy more expensive photo-compatible boards as well as you need a UV source.

I haven't etched in a while just because it is so much nicer (to me) to just have a board fabbed and shipped to my house with double sided traces, solder mask, and ahhhh...silkscreen.
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: muddyfox on November 24, 2013, 04:11:41 PM
I used to use those presensitized boards with OVH transparencies waaaay back (it's probably going on 20 years now) when you either used sunlight or a halogen floodlight (plenty of UV in there) like this one
(http://www.clarketooling.co.uk/tools/CHL500SD_Halogen_Floodlight500w230v.jpg)

and photoboards and regular copperboards cost about the same here (maybe 10% price difference).

Nowadays I don't even bother, I either buy boards from Madbean or whomever or have them fabbed. Especially with a small child in the house, acids are just way to dangerous to keep around (I don't have a mancave), with itead and seeed and oshpark prices being what they are.
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 24, 2013, 04:21:03 PM
Quote from: rullywowr on November 24, 2013, 04:02:15 PM
"I don't always etch myself, but when I do...." I am of the old school and when I etch just use some glossy photo paper or blue toner transfer paper with a laser printer.  I know if you don't have a laser printer you can go to staples or any copy shop and you can copy/print your design on the paper of your choosing.

While the photo-resist method comes out great, I think what puts people off from using it is the fact you need to buy more expensive photo-compatible boards as well as you need a UV source.

I haven't etched in a while just because it is so much nicer (to me) to just have a board fabbed and shipped to my house with double sided traces, solder mask, and ahhhh...silkscreen.
Yes, I know! Until now, I always went out to a photocopy shop and had my transfers printed. But it gets tiring to go out every time you want to etch something. I get tired of it.

I don't think it's that expensive, or at least it doesn't seem to me. As for the UV source, you can easily make one yourself. It's always about DIYing, isn't it?  ;)

As for the fabbed boards, I know they are perfect. But for a student like me, getting boards fabbed is still a lot more expensive. But then again, I don't know if I would have boards fabbed for me, because as I said, I got into this, because I love DIYing. So I prefer to do it myself, and have several difficulties in the process, instead of get my boards fabbed.  You know what I mean. ;)

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: croquet hoop on November 24, 2013, 04:30:12 PM
Fabbed boards are a whole different thing. Sure, the quality is great, you get double sided PCBs with silkscreen and plated holes, but you have to wait three to four weeks before you get them. Usually, when I receive a batch of boards from OSH park, I've already made a revision of the PCB in Eagle and almost use the PCBs I have with an afterthought, even when they work perfectly  ;D

With toner or photo etching, the gratification is immediate, and if you need something fast (and do not want to use vero or perf), the simple fact that you can create a PCB on the spot beats the fab solution.
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: davent on November 24, 2013, 06:10:11 PM
I've been etching with presensitized boards for years, toner transfer is too sadomasochistic for my lifestyle. Have only ever used regular flourescent tubes, first few i would stack a bunch of fat books on the kitchen counter to bring the exposure package up to the under-cabinet light fixture. Next up i screwed a scrap piece of plexiglass to the joist above my workbench where flourescent lights are mounted. Now just throw the exposure package up on the plexishelf and expose for ~9min.

A UV box will greatly reduce exposure times but for me it's  just one more thing i'd have to find a place to store other then the couple minutes i need it to expose a board every so not-so-often.

(http://i216.photobucket.com/albums/cc305/davent/IMG_1738.jpg)

The detail you can get is pretty incredible.

(http://i216.photobucket.com/albums/cc305/davent/IMG_3384.jpg)

dave
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 24, 2013, 08:42:05 PM
I've seen this picture before somewhere (I guess DIYSB)! ;)
The detail is impressive!  :o
BTW, that's a nice setup! Both for lighting and exposing boards!  ;D

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: muddyfox on November 24, 2013, 08:50:02 PM

Ah, the perks of a mancave... I gave up on diy boards because setting all this up and the etching all taking place on the dining room table just didn't sit well with the missus anymore. Not to mention that, living in an apartment, one quickly runs out of storage for "guy crap" as the missus fondly calls it...  ::)
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Gledison on November 24, 2013, 10:23:54 PM

As for the fabbed boards, I know they are perfect. But for a student like me, getting boards fabbed is still a lot more expensive. But then again, I don't know if I would have boards fabbed for me, because as I said, I got into this, because I love DIYing. So I prefer to do it myself, and have several difficulties in the process, instead of get my boards fabbed.  You know what I mean. ;)

Hector
[/quote]
hey Hector. im still using the annoying tonetransfer method. in my case, I have no much place for an extra UV lamp.
look, do you add a solder mask on your boards?
cheers
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 24, 2013, 11:15:52 PM
Quote from: Gledison on November 24, 2013, 10:23:54 PM
hey Hector. im still using the annoying tonetransfer method. in my case, I have no much place for an extra UV lamp.
look, do you add a solder mask on your boards?
cheers
No, I don't. I would, but it was quite expensive to buy. Maybe in the future!

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: haveyouseenhim on November 25, 2013, 12:57:11 AM
Where do you guys buy the photo boards? I would like to try em.
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: angrykoko on November 25, 2013, 01:25:17 AM
I use the photosensitive stuff too, easy as pie.  The most expensive part (for me) is the transpancy stuff for inkjet printers.
Warming the ferric chloride made the biggest difference for me getting really great etches.
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Stomptown on November 25, 2013, 04:28:18 AM
Quote from: Gledison on November 24, 2013, 10:23:54 PM

I don't know if I would have boards fabbed for me, because as I said, I got into this, because I love DIYing.

It seems like a lot of people feel this way! I personally love the feeling of getting my own board fabbed and it still feels like DIY to me, because in the end, I did the PCB design myself. I also feel a lot more confident about the quality of my builds when they are on fabbed PCB's. With etched boards I always wonder how long it will work for. Most likely a very long time, but that question always looms for me. I do love etching my enclosures though and having etches a good number of PCB's I definitely respect those who do it!
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 25, 2013, 07:29:34 AM
Quote from: haveyouseenhim on November 25, 2013, 12:57:11 AM
Where do you guys buy the photo boards? I would like to try em.
Mike, I buy them locally, so I don't know any online shop. But if anyone knows where to get reasonably-priced boards, please tell us.

Quote from: angrykoko on November 25, 2013, 01:25:17 AM
I use the photosensitive stuff too, easy as pie.  The most expensive part (for me) is the transpancy stuff for inkjet printers.
Warming the ferric chloride made the biggest difference for me getting really great etches.
Exactly. You couldn't have been more spot on! Indeed, the transparencies are quite expensive. Something like $0.70 -$0.80 per sheet here in Greece.
And indeed, warm ferric chloride is pretty essential. Also, developing your board really well is an important step.

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 25, 2013, 07:35:08 AM
Quote from: Stomptown on November 25, 2013, 04:28:18 AM
Quote from: Gledison on November 24, 2013, 10:23:54 PM

I don't know if I would have boards fabbed for me, because as I said, I got into this, because I love DIYing.

It seems like a lot of people feel this way! I personally love the feeling of getting my own board fabbed and it still feels like DIY to me, because in the end, I did the PCB design myself. I also feel a lot more confident about the quality of my builds when they are on fabbed PCB's. With etched boards I always wonder how long it will work for. Most likely a very long time, but that question always looms for me. I do love etching my enclosures though and having etches a good number of PCB's I definitely respect those who do it!
That's a quote from me, but nevermind!  :D
Yes, I know what you mean. Of course, the design is yours and getting fabbed boards in your pedals makes a huge difference (at least for the customer, if there is one). But for me, I want the end product to be a result of my own making, as far as I can. But then again, I can't insist of that, because I have never used fabbed boards in a pedal of mine. At the moment, it's an extra expense and I can't afford it.  ;)

Hector
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Gledison on November 25, 2013, 09:21:38 AM
Quote from: Ettore_M on November 24, 2013, 11:15:52 PM
Quote from: Gledison on November 24, 2013, 10:23:54 PM
hey Hector. im still using the annoying tonetransfer method. in my case, I have no much place for an extra UV lamp.
look, do you add a solder mask on your boards?
cheers
No, I don't. I would, but it was quite expensive to buy. Maybe in the future!

Hector
Im using a UV curable paint! It works pretty well! I posted a thread here on how to use it if u are interested...
Cheers
Title: Any love for presensitsed/photosensitive PCBs?
Post by: rullywowr on November 25, 2013, 12:58:32 PM
Quote from: Stomptown on November 25, 2013, 04:28:18 AM
Quote from: Gledison on November 24, 2013, 10:23:54 PM

I don't know if I would have boards fabbed for me, because as I said, I got into this, because I love DIYing.

It seems like a lot of people feel this way! I personally love the feeling of getting my own board fabbed and it still feels like DIY to me, because in the end, I did the PCB design myself. I also feel a lot more confident about the quality of my builds when they are on fabbed PCB's. With etched boards I always wonder how long it will work for. Most likely a very long time, but that question always looms for me. I do love etching my enclosures though and having etches a good number of PCB's I definitely respect those who do it!

This. I feel exactly the same!  Having your own boards made still feels DIY to me plus you have the advantage of sharing what you made easily. Once a board is good to go its a matter of "how many would you like". :)


Also, warming up my hydrogen peroxide/muriatic acid etching solution works very well. I usually etch in a small plastic container and float it in a slightly larger container filled with hot water. The heat speeds up the etching process significantly.
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Gledison on November 25, 2013, 01:06:22 PM
Quote from: rullywowr on November 25, 2013, 12:58:32 PM
Quote from: Stomptown on November 25, 2013, 04:28:18 AM
Quote from: Gledison on November 24, 2013, 10:23:54 PM

I don't know if I would have boards fabbed for me, because as I said, I got into this, because I love DIYing.

It seems like a lot of people feel this way! I personally love the feeling of getting my own board fabbed and it still feels like DIY to me, because in the end, I did the PCB design myself. I also feel a lot more confident about the quality of my builds when they are on fabbed PCB's. With etched boards I always wonder how long it will work for. Most likely a very long time, but that question always looms for me. I do love etching my enclosures though and having etches a good number of PCB's I definitely respect those who do it!

This. I feel exactly the same!  Having your own boards made still feels DIY to me plus you have the advantage of sharing what you made easily. Once a board is good to go its a matter of "how many would you like". :)


Also, warming up my hydrogen peroxide/muriatic acid etching solution works very well. I usually etch in a small plastic container and float it in a slightly larger container filled with hot water. The heat speeds up the etching process significantly.
Hey,
I do the same with ferric chloride! It etches quite quick using hot water as a warming bath!
Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: davent on November 25, 2013, 05:19:57 PM
Quote from: haveyouseenhim on November 25, 2013, 12:57:11 AM
Where do you guys buy the photo boards? I would like to try em.


Mike recently had the same discussion on another forum. Small Bear has the boards plus...

Quote from: daventCircuit Specialists also sell the MG Chemicals Developer where Small Bear points you to the lye route.

Amazon is another source for boards and developer AND free shipping on orders over $25.
http://www.amazon.com/MG-Chemicals-Positive-Developer-Liquid/dp/B005T8QLCY

Mouser shows the developer for US addresses, Allied show it, haven't found it at Digikey.

Google gives a bunch of sources. https://www.google.ca/search?q=mg+chemicals+positive+developer&oq=mg+chemicals+deve&aqs=chrome.3.69i57j0l3.19057j0&sourceid=chrome&ie=UTF-8

If you're in Canada and need to mail order developer Electrosonic is one source.
http://www.e-sonic.com/acc/products.aspx?partID=418-500ML&partIDExt=281&command=detail


A few more photo pcb's for tube and solid state projects. 2oz and 1oz boards. My toner transfer attempts at best were pitted with ragged edges to the etched traces, very nasty, ugly, ugly, ugly... but they did work.

(http://i216.photobucket.com/albums/cc305/davent/IMG_1368.jpg) (http://s216.photobucket.com/user/davent/media/IMG_1368.jpg.html)
(http://i216.photobucket.com/albums/cc305/davent/IMG_0322.jpg) (http://s216.photobucket.com/user/davent/media/IMG_0322.jpg.html)
(http://i216.photobucket.com/albums/cc305/davent/Cropped_IMG_0122.jpg) (http://s216.photobucket.com/user/davent/media/Cropped_IMG_0122.jpg.html)
(http://i216.photobucket.com/albums/cc305/davent/IMG_3743.jpg) (http://s216.photobucket.com/user/davent/media/IMG_3743.jpg.html)
(http://i216.photobucket.com/albums/cc305/davent/IMG_2526.jpg) (http://s216.photobucket.com/user/davent/media/IMG_2526.jpg.html)
(http://i216.photobucket.com/albums/cc305/davent/IMG_2521-1.jpg) (http://s216.photobucket.com/user/davent/media/IMG_2521-1.jpg.html)

A very good tutorial on this process:
https://www.smallbearelec.com/HowTos/PhotoPCBoards/PhotoPCBoards.htm

Some links for materials:
http://www.smallbearelec.com/servlet/Detail?no=1065
http://www.ebay.com/itm/5pc-Photo-coat-One-Side-Fibre-10x15-PCB-w-Accessories-U30-/380699549902?pt=LH_DefaultDomain_0&hash=item58a37620ce
http://www.circuitspecialists.com/printed-circuit-board-fabrication
https://www.acehomecenters.net/products/acid-muriatic-qt%7C12786.html

dave

Title: Re: Any love for presensitsed/photosensitive PCBs?
Post by: Ettore_M on November 25, 2013, 05:54:23 PM
That are some nice links you got there, Dave. Thanks! :)

Hector