Making PCB without a computer

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Beware of the stock footprints in any PCB program. They are often close to, or equal to the manufacturers recommendations which are optimized for machine insertion and wave soldering for leaded parts and pick and place with solder paste for SMD assembly. Neither of these are best for hand soldering by less than perfect DIY builders (rookies or old shaky hands like mine).

For many parts especially TO92's, but even for leaded resistors, I spread the leads and use larger pads.
 
Beware of the stock footprints in any PCB program...

...For many parts especially TO92's, but even for leaded resistors, I spread the leads and use larger pads.

In total agreement here.

That's why I like EspressPCB, I design all my own footprints with larger pads, typically 80 thou with 35 thou drill.

The only let down is that it's limited to round or square pads and no option for oval DIL style pads.
 
General rule I have:
If you want to make more than one of some PCB design, go computer, otherwise anything goes.
Although I've never done this, I've wanted to try a three dimension sculpture using discrete through hole components, no wire, just interconnecting leads. Pot it in clear liquid resin. The end result would look chaotic which most people assume is what electronics is about anyway.
 
The advantage of a well planned and thought PCB layout using a computer should be that of neatness and ease of identifying the various circuit elements. I am after that, and I also consider neatness as a plus. One simply cannot demonstrate the interior of an DIY amplifier if this is chaotically built. I want something worthy of admiration, and that, I am afraid requires great patience and perseverance.
 
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I used stationery correcting fluid as an etch resist. The result was a very decent looking PCB. The only 'defects' were some tracks were not smooth due to myself being nervous to get a good result. The etch resist I used was Ferric Chloride.


This procedure avoids having to use an over complicated PCB drawing program. Needless to state the obvious, if you plan to use SMDs, you cannot make a decent PCB without the help of a computer.
 
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...Needless to state the obvious, if you plan to use SMDs, you cannot make a decent PCB without the help of a computer.
A limited amount of SMT work is possible to do by hand. Resistors, capacitors and SOT-23 transistors are easy. SOIC packages are difficult, but possible. I never managed anything smaller than that.

Attached is a photo of a PCB with SMT components I drew by hand. Admittedly I did design the PCB on a computer beforehand, but I could just as easily have done that on a piece of paper. The trick is, after drawing it with an etch-resist pen, use a knife or other pointy object to remove any etch-resist bridging traces. That lets you get some quite fine trace widths.

Nowadays I use KiCad and a laser printer. I still prefer etching myself because that way I can go from layout to finished PCB in less than an hour.
 

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I once made a PCB for a circuit with an IC in TQFP-100 package using millimetre paper, a 0.5 mm fineline felt tip pen, a copier that could make 2:1 scaled down copies on transparant foil, a TL tube, a glass plate, PCB material with photoresist, developper and a plastic aquarium with iron chloride. I messed up two or three PCBs, but eventually I got one that was OK.
 
A limited amount of SMT work is possible to do by hand. Resistors, capacitors and SOT-23 transistors are easy. SOIC packages are difficult, but possible. I never managed anything smaller than that.

Attached is a photo of a PCB with SMT components I drew by hand. Admittedly I did design the PCB on a computer beforehand, but I could just as easily have done that on a piece of paper. The trick is, after drawing it with an etch-resist pen, use a knife or other pointy object to remove any etch-resist bridging traces. That lets you get some quite fine trace widths.

Nowadays I use KiCad and a laser printer. I still prefer etching myself because that way I can go from layout to finished PCB in less than an hour.

Correctly there is no point in automatic soldering, more time will be spent on preparing the SMT machine. So I did somehow the circuit board of the router, so there was a sense to use automatic soldering
 
This weekend I made a PCB by the manual "old school" method for a one-off simple board but using a slightly different method.

1. Cover PCB in masking or painters tape. Thin tape with weak glue works best, I used painters tape.
2. Draw traces on tape.
3. Cut out along trace edges and remove the tape where the TRACES go. Where the tape is will be etched away.
4. Spray with a light coat of (automotive) primer. Primer dries faster than paint and automotive primer likes to stick to clean metal.
5. Wait 15 minutes for the primer to dry and remove the tape.
6. Etch. The primer will protect the copper. I use hydrochloric acid and peroxide as an etchant and it didn't even affect the primer after an hour.
7. Remove the primer with lacquer/acetone/sandpaper (I actually used my fingernails to remove 95% of it then sanded lightly with wet 600 grit).

This method doesn't have the problem of etchant lifting the tape or getting under the edges.
 
In total agreement here.

That's why I like EspressPCB, I design all my own footprints with larger pads, typically 80 thou with 35 thou drill.

The only let down is that it's limited to round or square pads and no option for oval DIL style pads.

My software allows square, rectangular, circular and obround pads.

With the onset of very cheap Chinese pcb makers I don't bother with making my own pcb's now. I would be inclined to just buy a cheap second hand laptop and design my own and get Mr China to make them for me for peanuts.

SMD is great fun, I had a go at a 64 pin TQFP 0.5mm pitch. I aligned IC perfectly then blobbed a load of solder down one side to hold it. I then blobbed the other 3 sides. I removed excess solder with copper braid.
What I did with the pcb was have lines of vias down each side of the IC so I could buzz the adjacent pins for shorts. I have now down about 5 of these packages. I only had one to throw away where I had been to rough and bent a couple of pins together shorting them out.

On my latest pcb I have a 64 pin SMD and a 28 pin SMD device, so I got PCBWAY to solder them on for me. Not cheap for just two components but it was ok for a prototype.
 
In the mid-1980s, I used a DALO etch-resistant pen. It looks like you can still get them: T0033 Blue PCB ( Dalo ) Etch Resist Pen - Altronics

I would draw the layout on drafting paper with mm markings and transfer the hole centres to the PCB material using a small centre punch or scribe. Then "just" draw the traces with the DALO pen, etch, and drill.

These days PCB layout software is free and PCB manufacturing in prototype quantities is almost free, so I see no reason to mess with DALO pens and PCB etchant anymore. The only drawback of the prototype services is that they take some time. I can etch and drill a board in my garage in a few hours. Matching such timeline is impossible for the prototyping services.

Tom
 
This weekend I made a PCB by the manual "old school" method for a one-off simple board but using a slightly different method.

1. Cover PCB in masking or painters tape. Thin tape with weak glue works best, I used painters tape.
2. Draw traces on tape.
3. Cut out along trace edges and remove the tape where the TRACES go. Where the tape is will be etched away.
4. Spray with a light coat of (automotive) primer. Primer dries faster than paint and automotive primer likes to stick to clean metal.
5. Wait 15 minutes for the primer to dry and remove the tape.
6. Etch. The primer will protect the copper. I use hydrochloric acid and peroxide as an etchant and it didn't even affect the primer after an hour.
7. Remove the primer with lacquer/acetone/sandpaper (I actually used my fingernails to remove 95% of it then sanded lightly with wet 600 grit).

This method doesn't have the problem of etchant lifting the tape or getting under the edges.

This sound like an excellent idea. I will try it.
 
Good

I remember in the 1980's our draughtsman designing pcb's that way.

The world has moved on greatly since then. No kidding, there are hundreds of pcb design packages for a pc. From very simple to highly complex packages.

I remember buying EasyPC in around 1990 and getting tripped up by all the bugs in it !

The cost of pcb's is now rock bottom. I just bought 10 off 100mm by 100m pcb's for $2 with jlcpcb. OK the p+p was a bit but I wanted them quickly. Slow post is just a few $.

I would recommend biting the bullet and getting stuck into a PC PCBCAD package. I often find I can pinch bits from different schematics and merge them for a new pcb saving me hours of work.

Autorouters are a big no no. Although, I run mine and then go in and fix star grounding etc.


Thank you very good
 
Today, I made a stereo LM3886 amplifier PCB based on a PCB layout found on these fora. Using a print of the PCB layout, the hole centres were transferred to the PCB using a sharp tool. Then, I used contact plastic to trace the shape of the largest and widest tracks which I cut with a pair of scissors. These wide tracks were then stuck to the copper side on the PCB. The smaller tracks were created using correcting fluid. Imperfections were trimmed using sharp tools like precision screwdrivers and a miniature knife.

The concoction so formed, was then placed in a Ferric Chloride solution and rocked to and fro for about 15 minutes.

The result is a clean and beautiful homemade PCB.
 
I have used etch resist pens in a similar way (not dalo but blue ink still) and 0.1 SRP board (copper less, with 0.1" matrix)

Using this board and pen, I'd make component pin locations, remove the overlaid board and put components in their places. Then join the dots, and etch.

But hell, those pens are awful. It's a messy method and more like painting, because if not thick enough the etch resist does nothing.

I much preferred using 5mm or 0.1" squared paper, to draw the traces, and then apply the self adhesive tapes for tracks and pads on to a transparency overlaid on the drawing. Then expose and develop and etch.

Another method that has worked ok (better than iron on techniques that have become popular) is to simply draw the traces onto thin 0.1" matrix paper, with a good opaque indelible marker (OHP pens with tip of 0.5mm or so).
Then paint on a thin layer of oil (baby oil for example) to make the paper more translucent. Then expose, develop and etch.
 
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