Making circuit boards

[M0BSW]

 I know I have a lot of questions, but the only way to find out is to ask,  Making Circuits , iremember years ago Maplins used to sell ferro ectchant kits, now they seem to sell photo ecthant kits, oh oh ,now I'm lost do you need a some special equipment for this, I would like to make some simple boards, I've heard some radio hams who do make boards say something about those purple tubes in a box, or is there a easier way.
Paul

[Rerouter]

you can still buy ferric chloride or absolutly worst case make some from some pretty generic chemicals,

as for the photo kits they require a few more steps and really arent the best choice for a beginner, as there are more steps and require a bit of experience to get good yeilds at first
e.g. expose pattern via transparent film in a UV light box, develop in a chemical, etch conventionally then scrub off your resist as normal,

[george graves]

IMHO, the quickest way to get started is the toner transfer method, a cloth iron, w/ magazine paper and Muriatic acid/hydrogen peroxide and PCB ordered from ebay.

I suggest 1/32" think copper clad - you can cut it with tin snips.

Google "toner transfer method" - there's a few hundred tutorials.

[M0BSW]

Thank you both , I was getting worried there, thought I would have to use strip board forever more.
Paul

[M0BSW]

I've just watched a video on You Tube ,if I got it right  , I can print the track layout that we get in Radcom  for instance, print it on glossy paper iron it at max, put it in hot water and peal off paper, then into the ferric echant, clean it off with aceatone or nail varnish remover job done,
I've got to have a go at this, i've a book full of circuits I've wanted for Years, this is like a whole NEW world to me, thanks for pointing me in the right direction, I'll leave you in peace  for a while lots to consider.
Paul

[Jimmy the Squid]

Check out Tayda electronics for inexpensive copper clad boards. They sell six-inch squares for just over a dollar each plus shipping. They are a Thai company, but they ship fast and have a devoted customer base (including me).

The boards are cheap enough that you won't mind screwing a few of them up.  I happen to have a few laying around, but I haven't gotten around to etching them yet. I attached a pic so you can see the item. The pot in the corner is just for size reference. Also, forgive the mess on my bench.

[M0BSW]

 Crickey Jimmy htere worth a buy, i'll look into that,i've got several circuits I want to build , in the cold winter months
Thank You

[RCMR]

Yes, I use the toner-transfer method and you can buy ferric chloride from Element14 for a reasonable price.

The choice of paper is the most crucial factor in the success of the toner-transfer method -- some magazines are better than others and you need to make sure you print only on the "white" areas -- pigment in the paper can stuff up the results.

However, my boards turn out pretty good -- even with 8mil tracks.

[T4P]

Check out Tayda electronics for inexpensive copper clad boards. They sell six-inch squares for just over a dollar each plus shipping. They are a Thai company, but they ship fast and have a devoted customer base (including me).

The boards are cheap enough that you won't mind screwing a few of them up.  I happen to have a few laying around, but I haven't gotten around to etching them yet. I attached a pic so you can see the item. The pot in the corner is just for size reference. Also, forgive the mess on my bench.

I'm a fan of them 

[Jon Chandler]

Something to think about is that the cost of professionally made boards has come way down recently... iTead and Seeed will make 50mm x 50mm boards for about $15 delivered, and 100mm x 100mm boards for about $25...for TEN BOARDS.

Depending on the complexity of your design, especially if a double-sided board is desirable, a commercially made board may be a good option.

This link includes sources I have used or am familiar with.  It's far from complete, but I know these vendors produce good boards.

PCB Fabrication Sources

[M0BSW]

 So you can use magzine paper if I'm catching it right, its sort of make sense now when a another radio ham I spoke to tonight, said he uses newspapers the clear bit on adverts, I wondered what the heck is he talking about, now having read this it makes perfect sense, if it does I'll be buying the Sunday papers tomorrow that's for sure.

[M0BSW]

Thank you Jon, I'm not that good, that's a bit down the line, simple stuff at the moment, while I feel my feet.
I'll keep the link thank you.
Paul

[Jon Chandler]

Just making sure you were aware of the possibilities Paul.  The cost has dropped so much recently it's hard to believe.

Some people are able to make really nice DIY boards but the process never seems to work that well for me.  If I do get a nice result, the drilling seems to take forever, with many broken bits in the process.

[Psi]

If you find you cannot get the toner image to transfer properly from the glossy paper to your PCB try some proper PCB transfer paper designed for the purpose. Like press-n-peel blue or the pulsar stuff.

Using glossy paper is quite unpredictable as there are so many types and only some of them work.

Also, if you drill the holes first, make sure you remove any burrs or they will stop the paper sitting flat on the pcb.
I find its best to drill the holes after etching

You will get a bit of side etching so thin tracks will get thinner.

[LDSisHere]

Over the past year I have been etching my own boards using the toner transfer method and it takes a lot of trial and effort to get good results.  The paper used is very important as it has to release the toner easily.  I have also discovered that for me, using a cloths iron gave inconsistent results as well as being time and labor intensive.  I then discovered this paper: Hammermill Color Laser Gloss Paper, 94 Brightness, 32lb, Letter Size, 300 Sheets per Pack (16311-0).  I am not sure if it is available where you live but I can find it on Amazon for less than $10.  The other major break though for me was buying an "new" old style Creative laminator.  I had intended to do a temperature mod to it, I even bought the parts, but it works as is so I have not bothered with it yet.  I have also read a lot of people having problems with the toner in their laser printers, but mine seems to work well.  For boards I bought a 20 lb. box of odd lot double sided PCB off of Ebay that only cost $35 with shipping and that should last me for years. 

IMHO you need to experiment and find what works for you, your goals and your budget.  But for now you are doing the right thing by asking questions first and learning from other peoples mistakes and successes.

[RCMR]

Yes, for toner-transfer the HP lasers are much better than the more common (and cheaper) Brother ones -- apparently the Brother toner melts at a higher temperature.

I've tried various glossy inkjet paper but found that with the Brother printer, the heat required to transfer the toner also results in the glossy layer of the paper bonding to the PCB as well -- making the results pretty crappy.

Yes, you can get PCBs done professionally for quite a low cost now -- but it's the turn-around time that's usually the reason I make my own.  Often I design and build stuff with very tight timeframes so I'll hand-etch a board and have it ready for soldering within an hour of finalizing the layout.

[M0BSW]

Thank you all for answering and giving ypur time to do so. I will start small, and post the results good or bad.
Paul

[Smokey]

I used to etch all my own boards in HCL and H2O2.  Kinkos copy centers had the best laser printers and paper for transfer.  I'm sure everyone at the local shop thought I was crazy printing all those copies of gerbers on the business center computers.  It was pretty rewarding at the time, but also seriously frustrating.  I only did it because professionally made boards were too expensive.  That's not the case anymore.  Now it is even more rewarding to do a clean layout and have a PCB that actually looks like a finished product.

The conclusion I came to was that etching your own boards is one of those skills that takes a lot of trial and error and time and frustration to get right, but the skills you learn don't transfer to anything.  It's not a skill that you can use later on when you progress.  I'd take the bet that your EE job won't require you to hand etch boards.  I found that the designs I did for home etched boards were overly convoluted in order to keep them on 1 layer and I was stuck with all through hole components and huge trace/space clearances if I wanted anything better than 1 in 10 boards to work.  If you progress to professional made multilayer boards with SMD components, it's a whole different ballgame as far as how you approach layouts and component selection options.  Things like ground planes are really hard to do with 1 layer home etch, but will make your designs significantly better.  Those are skills that you will use for your entire design career.

I'd say, unless you just want to say that you did it, skip the home etch and get boards made at iteed or some other cheap board house.  It's not more simple home etching.  Home etching is all the work of doing an overly constrained layout with the frustration of low board yield on top of it.  And the boards are ugly and have no reference designators.  If you are prototyping something, use a perfboard or a breadboard.  If you want to make a real PCB, get it done at a board house.  That's how I feel about it at this point at least.  Rant over. 

[M0BSW]

 Well chaps, i actually contacted a company here in the UK, I couldn't believe how cheap it is to have a custom board made, there is this circuit in RadCom digital SWR meter for ham Radio, over a couple of emails , they said scan a copy of the circuit to them and they can knock the board and deliver in 2/3 days, no mess no added expense, none of my mistakes, sounds like a plan to me, still want to do some to say I can.

[ptricks]

For making your own  boards at home do it the way the professionals do it with the photo/uv process. You can truly turn out some quality designs using this method and there is no problems like messing with toner and trying to get it to transfer to the board.

All you need is:
Laminator - can use any brand, doesn't matter as long as it gets hot and you can feed the board through it, cost about $20 USD
Photoresist film - about .75  USD per sheet
developer for film - $3USD and last for about 100 boards
transparency sheets for a laser printer
light source - CFL bulbs work great
small piece of glass , old picture frame glass works fine

At first I was scared of using this process and that it would be too difficult, boy was I wrong. I can now go from printing the design to etching a board in 30 minutes for a double sided board and most of that is the 20 minutes to expose the board to UV light.

You need a room with low light, the film is sensitive to UV light so something like those yellow bug lights will not expose the film.
Clean the copper clad like you normally would for toner transfer.
Peel off the inner side of the film and place it on the board.
Feed the board into the laminator
Repeat for the other side if you are doing double sided boards.
Place your transparency sheet with the design over the board then cover with the glass so the sheet is tight against the board
turn on the CFL light positioned about 12 inches away from the board.
Wait 10-12 minutes.
Turn off the light, flip the board, put on the new pattern , and expose that side for 10-12 minutes
Remove the plastic cover off the film that is there to keep the transparency from sticking to it.
Place board in developer and shake the container slightly to agitate the developer across the board the film that was not exposed will wash away
Rinse in water
Board is now ready to etch.

Here is an example of how fine a line you can get with the photo process, sorry for the pic quality, this is an example of how the design looks on the transparency sheet .
The good thing about this process is you can make a book of all your designs and re-use them whenever you need to.

[M0BSW]

Wow another lesson  I'm going to have to read this one a few times, I thought I got it all sorted as well.
paul