Diy PCB Issues

Thread Starter

Dr.killjoy

Joined Apr 28, 2013
1,196
@GopherT

You can skip the glass if you use translucent polyester paper and a drop of water. You get nice dark line. The drop of water creates surface tension between the PCB and the paper and it sticks very well.

A mix of vinegar and salt will easily clean oxidized copper.

One time when I was doing PCB's, I had access to a IC mask aligner which could only expose 4" x 4" max. The spin coater for applying resist was just as restrictive. Exposure was easy to set with a UV meter. The liquid resist was applied with a spin coater and then baked.
 

Thread Starter

Dr.killjoy

Joined Apr 28, 2013
1,196
Also I don't have a laminator but have a travel clothes iron which should work I think.. But still might look into finding a laminator..
Oh should I look into building some kind of timer circuit with relay for the exposer time ??
I plan on using ferrite chloride as a etchant and using the sponge method. Then plan on using all SMD parts if possible because I don't have a small drill press and will have to use a speed control ebay hand drill.. I might look into picking up some quality Irwin drill bits but have to figure out what size I should get..


@KeepItSimpleStupid
Awesome idea on using spin coater and should work perfectly with solder mask too
 

ClassOfZero

Joined Dec 28, 2016
114
For thru hole components you really want high rpm, 20 - 30k, dremel range.

Get a laminator they are dirt cheap, if you wanna be tricky you may want to mod it to about 100'C max. As for a timer, meh I just went to the el cheapo variety store and bought a cheapy. Personally I'd spend money on the laminator rather than a timer system for exposure to begin with, getting the resist stuck down properly can be a bit tricky at first. ATM I have two laminators, one unmodded for photo resist and the second modded for toner transfer.

If you do make a trip to the local el' cheapo variety store, be sure to grab some plastic containers, preferably with lock on lids, (not knowing your domestic situation, but it pays to keep SWBO happy and not use too much from the kitchen) and some small brushes like kids use. Oh yeah and if they have a set of small digtal scales grab them as well, comes in useful for measuring all your various powders & water.

Good suggestion about a drop of water & surface tension.
 

Blockhead

Joined Oct 23, 2016
9
You really do need UV (Blacklight) tubes for the correct frequency to work with the resist.

http://www.fusun-toshiba.com/catalogue/Special_FL2.pdf

The link to the Toshiba site gives some information to the correct type of tube.
The last tube I purchased was around $15. If you are going to make circuit boards then you really need to make or purchase a proper light box. UV light exposure isn't particularly bad unless it it close to you and its main effect is on your eyes. Prolonged exposure to high UV light levels will cause a "film" to grow across the surface of your eyes. Putting a lid on the box will prevent any exposure.
When I get back to work in a couple of weeks I will put together some photo instructions on how to make a PCB and if I get time I will also make a light box and put together instructions on how to make one.
 

shortbus

Joined Sep 30, 2009
10,050
Right now I have a ice blue CFL light I use as my work light.. The work light is a multi bulb lamp and should work great for my intended purpose.. I am trying to stay away from UV if all possible and have seen and read alot of people with great success using CFL bulbs..
Why do you think that something that needs UV to work, is working with CFL lamps? It's the UV they put out.
https://en.wikipedia.org/wiki/Fluorescent_lamps_and_health#Ultraviolet_radiation_risk
 

cmartinez

Joined Jan 17, 2007
8,762
For the last couple day I have been playing with the Toner Transfer method and failed completely.. I am using the Brother HL-L2305W laser jet printer.. Tried using the glossy paper and wax paper too and both failed.... Right now I am at a loss and looking for other avenues.. The Blue Press-n-peel looks good but not sure if it work with the brother laser jet and not cheap to boot .. The photo resist seems the only option, but I am allergic to UV light which makes it even more fun lol.. So has anyone had any luck with the cheap ebay photo resist kit or have another suggestion???
Have you taken a look at this post, and at this thread?
This other thread might also be relevant.
 

Thread Starter

Dr.killjoy

Joined Apr 28, 2013
1,196
Well I found a 15min timer relay from a Vintage R/C charger which should make a perfect timer since it has a large sweep and can handle 120v 10amps. The photo resist should be he Saturday with chemicals.. Still need to get some etchant from radio shack later down the road after I get my printing done to where I want them ..Hopefully I will get a chance this weekend to bang some out and will post up the results..
Also does anyone has suggestion for some kind of down and dirty silkscreen ????


Oh will post replies later after work..
 

bertz

Joined Nov 11, 2013
327
Well I found a 15min timer relay from a Vintage R/C charger which should make a perfect timer since it has a large sweep and can handle 120v 10amps. The photo resist should be he Saturday with chemicals.. Still need to get some etchant from radio shack later down the road after I get my printing done to where I want them ..Hopefully I will get a chance this weekend to bang some out and will post up the results..
Also does anyone has suggestion for some kind of down and dirty silkscreen ????


Oh will post replies later after work..
I used to make my own PCBs. I started with the Toner Transfer Method. I got the best results using Pulsar Toner Transfer Paper and a laminator. Forget about using a hand iron - that only works in the movies. I also used the Pulsar Paper for the Silk Screen. My PCB software was Express PCB (free). I was less than pleased with the results although I did produce some fairly complex PCBs.

Then I found a couple sources of pre-sensitized PCBs on e-Bay and decided to give that route a go. I built my own exposure box using UV LEDs, used dilute NaOH for developer and FeCl for etching. The results were a significant upgrade over the Toner Transfer method, but I still had to use Toner Transfer Paper for the silkscreen. Then the prices started to go up on pre-sensitized board and free shipping was no longer offered as an option. Damn! These things are getting expensive, not to mention the time and effort to develop, etch and drill.

Now I no longer bother etching. The price of PCB services has come down dramatically and the DIY product cannot even come close in quality. You can get 5 two-sided boards made by ELECROW for less than $10.00 US. That includes drilling, solder mask, silkscreen and plated through holes. You can't DIY for that price. Incidentally, I switched to Diptrace to make the Gerber files. It's free and much easier to use than Eagle.
Just wanted to share my experiences with you. Good luck on whichever way you choose to go!
 

Thread Starter

Dr.killjoy

Joined Apr 28, 2013
1,196
Sorry about the late response
I managed to take a ride to my local thrift store and picked up a 4" laminator, chopsticks,and glassware.. I still have to get ferrite chloride,transparency,and glass holder.. Also the photoresist was suppose to be delivery today but got delay.. The laminator is small I know but should work for the time being and have to research what kind of mods are need to make it work for pcbs..

@KeepItSimpleStupid
Thanks for the great suggestions and the spin coater is pure genius..
@ClassOfZero
Yeah thats a great thread and Wendy put together another great thread too..
@shortbus
I am highly allergic to certain uv light.. The uv light they use in blacklights and tanning beds causes my skin to turn bright red within a couple seconds or I get really ill..
So far I haven't had any problems with ice blue cfl and can be used with good result I hope for photoresist..
@cmartinez
Wow I completely forgot about those thread..
I went threw your threads again and learned alot.. With not having the money or room for that kind of invested is a problem



@bertz
I understand where you are coming from and what works best for you.. For me I am only learning electronics in my spare time and have come pretty far.. Right now I have a couple pcbs designs that I would like to see completed and running.. The problem right now for me is learning basic pcb design and setups.. In which making my own I can learn the errors of my ways and make changes on the fly..For a design software I choose Kicad.. Thanks for link pcb manf house ..Also if I need a more professional pcb then I have the option to have a PCB manufacture house do it..
 

Thread Starter

Dr.killjoy

Joined Apr 28, 2013
1,196
You may come up with nothing if you ask for that.:) It's ferric chloride, not ferrite chloride.
You caught me lol..



The other day I got some more stuff and there is not much left to get..I managed to mod the laminator to be able to take pcb's and not tear the gears up.. So my first pcb failed completely and second will be posted below.. There is alot of mistakes that I have to work threw and will design my own negative photoresist print..I used A&H super washing soda which can be used for a developer but have to figure out the right mix for single use batches..Also I am using tracing paper instead of standard transparency's and it came out pretty good but needs more time under the CFL which this sat for about 11-12mins..
 

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Thread Starter

Dr.killjoy

Joined Apr 28, 2013
1,196
Would anyone be interested in me making a thread and or blog about using Chinese Photoresist off ebay and all the links to great material ??
 
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