stuffing boards...workflow?

what is everyones order of work for stuffing pcbs? do you do it from left to right, all resistors then all caps etc.. or just randomly? im sure there is no right way, just wondering if there are any tips or hints.

For ease of stuffing, I go from the smallest components closest to the PC board (e.g. resistors, diodes) so that I'm not stuck maneuvering a resistor between two closely-spaced IC sockets with my infamously large fingers.

For debugging purposes, consider stuffing the power supply first before you start stuffing in expensive IC's. No circuit will work if the PSU is hosed, and if you power it on and it sacrifices itself as a burnt offering to the semiconductor gods, you're Mouser order will be a whole lot smaller.

In order of height.

Resistors and other board-huggers first, then taller components.

Think about it... trying to fit a tiny part in tight between two taller caps (f'rexample) is a pain in the buttkus.

Keith

I put in the bread crumbs, then the spices, then the gravy mix.
Bake at 375 unttil the button pops.

Are they going to have un leaded turkeys this season?

grab and go.

order not important.


get some friends, a cup of coffee, take your time, put on tunes AND TV, because thats how I party, if you are not talkin it up with some cute vietnamese chick (small hands -= good stuffers)while stuffing, your a loser, double check color codes, some precicion parts read from both sides of the resitor causing suicides and forum troubleshooting threads that drag for days, ie 1176.

ohm out every resistor just in caee, watch polarity of tants, get a piece of 1/2 inch styrofoam, this holds the leads , trim resistor leads to 1/4 inch before stuffing,

im out.

First a scan of both sides of the board,
then solder the wire-bridges (add teflon-isolation if you forsee later components coming close),
then resistors & IC- & eventual transistor- and/or tube-sockets & some headers,
then put it away for half a year,
then add film- & ceramic-caps,
add rest of the headers'n'connectors,
wait another few months,
add electrolytics... etc

And have the schematic to double check against the bom
this also helps you learn and become more familer with the circuit

I second cj's checking resister values [ i can't tell the colors half of the
time on the blue 1% resisters ] also good for matching in the balenced circuits .

Cj , yowse nuts butcha gots some right ? chunk ?

It is also helpful to insert resistors and non-polarized caps so that the values/color codes are readable from only two sides (as in mechanical drawings where numbers+text are readable from the bottom or the right side of the sheet).

In the end when large vertical parts that don't like bending (TO220 voltage regulators etc.) are getting soldered in, i put 25mm pcb standoffs (on the component side) in the mounting holes so that the board can be worked on solder side up without parts getting bent.

I always start with resistors or diodes. Usually I'll find the value with the most, like 10k and stuff all the 10k's, then I'll move on to the next value, and so on and so forth until all the resistors are done. Then go to tants or film caps, then lytics.

Adam

[quote author="CJ"]some precicion parts read from both sides of the resitor causing suicides and forum troubleshooting threads that drag for days, ie 1176..[/quote]
Days?? I wish it was that short.

Agree with McCroskey that it's helpful to bring things up in sections and test along the way, starting with the power supplies. If you're stuffing tried-and-true PCBs this is less important, but if it's a new design it's highly recommended.

Another very helpful tool is a mains power meter like the Valhalla series; short of that, an a.c. ammeter in the mains input. This is especially good when there's a lot of power involved. If you're really nervous, bringing things up slowly with a variable autoformer can reduce the incidence of damage when you haven't spotted the errors yet.

and related to that, put in semis last, that way, if you use a wrist band, like you should, you only have to wear it for a little while.

I agree with height, shortest to tallest. There are two things that make it easier after that, especially if you are doing multiple boards-
The first goes for anything- use scotch-brite on the leads to clean them. The time taken to do this reduces the heat time when soldering. If you have a dermel, make a mini scotch wheel and go motorized.
Second, I use foam to hold components, except for IC's. You can write values on it, load the foam like the board- imagine loading 20 DOA's from a piece of foam with all components in groups located where they go on the board.
The foam method has been a time-saver for me with runs over 5 pieces of boards or switch assemblies.
Mike

Eveyone said it but I'll just add.

Jumper wires first... then resistors and diodes.

[quote author="clintrubber"]First a scan of both sides of the board,
then solder the wire-bridges (add teflon-isolation if you forsee later components coming close),
then resistors & IC- & eventual transistor- and/or tube-sockets & some headers,
then put it away for half a year,
then add film- & ceramic-caps,
add rest of the headers'n'connectors,
wait another few months,
add electrolytics... etc[/quote]

That's some funny stuff there... :green:

Your forgot:
Then when it's finally finished, check it with a scope
lend it to a friend for his opinion
Wait a year
Start another one because your friend won't give it back

I will ASSume you are asking about designs involving through hole parts.

Back when I ran a kit company, my step by step instructions advised resistors and jumpers first, IC sockets, capacitors, pots & switches, then ICs. The strategy is height and cost of components. The height consideration is so board will lay flat or stable when you turn it over to solder leads. Shorter components, installed after taller, could fall out or move when flipped to work on, and board gets bounced around by working on it.

The vast majority of my customers had success with this strategy, while I would get a handful back for repair. Typical errors seemed dyslexia like wiring reversed, etc. Worst one had component installed onto solder side of PCB. It would have actually worked if ICs weren't oriented wrong.

JR

[quote author="JohnRoberts"]Typical errors seemed dyslexia like wiring reversed, etc. Worst one had component installed onto solder side of PCB. It would have actually worked if ICs weren't oriented wrong.

JR[/quote]

My late father had some boards etched and didn't get the IC pinout imaged correctly. Rather than scrap them, he bent all the IC leads 180 and installed them thus. I had tried to help, but I wanted to fix his circuit as a condition, since I was always having to band-aid it when the not-very-capable one didn't work. It was one of those "free" circuits that he found that are worth about what you pay for them.

It particularly grated that he insisted on referring to the key section as a "standard flip-flop", which it was anything but. Suitably modified though, it became the basis for a fairly successful distributed latch-cancel system, so in the end I was glad I'd had my nose rubbed in it.

[quote author="Emperor-TK"][quote author="clintrubber"]First a scan of both sides of the board,
then solder the wire-bridges (add teflon-isolation if you forsee later components coming close),
then resistors & IC- & eventual transistor- and/or tube-sockets & some headers,
then put it away for half a year,
then add film- & ceramic-caps,
add rest of the headers'n'connectors,
wait another few months,
add electrolytics... etc[/quote]

That's some funny stuff there... :green:

Your forgot:
Then when it's finally finished, check it with a scope
lend it to a friend for his opinion
Wait a year
Start another one because your friend won't give it back[/quote]
:thumb:

[quote author="sodderboy"]Second, I use foam to hold components, except for IC's.[/quote]
The conductive black foam ? Yep, good idea.

You already made the exception for ICs, but just in case let's add a warning that when you use the 'white foam' (piepschuim, Styropor of Styrofoam) you don't want to use that for static sensitive components (or cover it with alu-foil before sticking components in).

Regards,

Peter

OMG John Roberts thats the funniest thing I ever heard!

I do IC's last regardless of the height issue. But jumpers first then resistors. And speaking of resist.... Resist the temptation to bend leads on the action side of PC board. Makes it hard to wick or suck them out. And can cause solder bridges to adjacent pads.

Tip: If a panel switch or pot needs to lay flat and you only got 2 hands. Put a small solder blob on your iron and touch it to a critical lead while you hold it with your only free hand. It will lock down. Let it cool and check alignment. If aok then you can weld the rest of the leads on.

Tip 2: CMOS chips and others can fail from static discharge. Even if at first they work. Their lifespan can be greatly reduced. So be grounded for the semiconductors.

Tip 3: Use a soldering iron not a soldering gun. The soldering gun was used back In the Black Sabbath days and did a magnetomic beam that created Iron Man I believe his name was. He's not cool for audio circuits. Time travel causes "Latency" not good.

[quote author="JohnRoberts"]Worst one had component installed onto solder side of PCB. It would have actually worked if ICs weren't oriented wrong.[/quote]
Those big chrome Morley pedals did that... don't believe these were double-sided PCBs... easy to trace !