PCB Preferences?

[Kearns892]

Hey all,

I was thinking about designing some PCB layouts for common circuits that either don't have verified PCB artwork or I felt could benefit from a better design.

I would love to share them with the forum when I am done as a way to give back to the community here, and as such I was wondering what features people preferred in PCB designs.

Here I have a quick 5 multiple choice question survey that shouldn't take more than a minute asking about a few features in PCB design and I would really appreciate some input.

Survey


This isn't intended to be about which method is "better" as this is all just builder preference, which is subjective, but feel free to post about which features are most important to you and why.

Thanks!

[Kearns892]

This is going great thanks for the input and keep it coming guys. Right now I am noticing that the final question regarding board types is pretty evenly split.

Anyone want to pitch in on pros and cons and the intensity of the preferences of a Modular board vs. a Minimal footprint board vs. a Thought-out but Compact Layout? 

[R.G.]

Just as a bit of commentary, my opinions:

Q.1
On your PCBs, which do you prefer? *
    * .01 inch Grid Layout
    * No Grid Layout
    * No Preference

I think you meant 0.1" grid.  For beginners, 0.1" grid is the smallest usable part placement, and many complain about that. For the experienced, 0.025" grid (which means that part pins are snapped to the nearest 0.025" ) is entirely practical with 0.025" and 0.012" traces. Depending on layout skill, of course.

Q.2
On your PCBs, how do you like your resistors mounted? *
    * Flat
    * Upright
    * Mixed/ Smallest Footprint
    * No Preference

Flat is the only thing that makes sense unless you're in a frenzy about getting the smallest board. Upright resistors are very difficult to *document* correctly, difficult to check, and much, much harder to repair. All these are critical to beginners. Even the folks who brought you "Japanese Radio Style" mounting no longer mount resistors on end except in unusual cases.

Q.3
On your PCBs, how do you like your board mounted? *
    * Board Mounted Pots
    * Spaces for PCB Standoffs
    * No Mounting/ No Preference

For amateurs, spaces for PCB standoffs are the only practical choice. There are difficulties with the others; no mounting preparation is shortsighted and leads to unfortunate compromises in the actual box, and board mounted pots means the PCB is critically dependent on the builder being able to find that one, specific pot to use; that's not always easy or even possible.

Q.4
On your PCBs, what status indicator LED options do you like to have? *
    * Board Mounted LED and On-Board Current Limiting Resistor
    * On-Board Current Limiting Resistor
    * No Status LED or Completely Off-Board LED wiring

Mostly moot. on-board LED only makes sense if the LED and pots are integrated onto the board, and that's a problem for beginners and amateurs as noted above. Off-board LED resistor is a bad choice. Stringing any part across space on its leads is a reliability issue waiting to happen.

Q.5
How do you prefer your PCBs? *
    * Smallest Footprint (Area Minimized at Expense of Layout, Off-Board Wiring Pads Being at Edge, etc.)

Bad idea in general. Pads should always come out to the board's edge and think really, really hard about ever bringing them out to more than one edge. Otherwise, you wind up with the PCB being laced down like Gulliver in Lilliput. Bad for service and repairs and horrible for beginners who absolutely will need to debug.

* Compact and Well Laid Out (More Spacious/ Neater Layout, Off-Board Wiring Pads at Edge, etc.)

This is the only thing that is practical for almost all situations. Only vary away from compact and well laid out if there is a specific, easily articulated reason not to do it.

* Modular (Larger Area, Additional Pads for Mods/Variations, Universal Trim Pot Pads, etc.)

Good for experimenters, but I've had remarkably few takers on the boards I've set up for modularity.

[Kearns892]

Thanks for the input R.G.

I think you meant 0.1" grid.  For beginners, 0.1" grid is the smallest usable part placement, and many complain about that. For the experienced, 0.025" grid (which means that part pins are snapped to the nearest 0.025" ) is entirely practical with 0.025" and 0.012" traces. Depending on layout skill, of course.

Typo, Supposed to be 0.1 inches. Thanks for pointing that out!

For amateurs, spaces for PCB standoffs are the only practical choice. There are difficulties with the others; no mounting preparation is shortsighted and leads to unfortunate compromises in the actual box, and board mounted pots means the PCB is critically dependent on the builder being able to find that one, specific pot to use; that's not always easy or even possible.

Personally, I agree; however I know the Tayda and Futurlec style of PCB mount parts are popular here, and if the pot can't be found it can still be wired off-board. I think standoffs are the way to go, but board mounted pots definitely have their merits.

Bad idea in general. Pads should always come out to the board's edge and think really, really hard about ever bringing them out to more than one edge. Otherwise, you wind up with the PCB being laced down like Gulliver in Lilliput. Bad for service and repairs and horrible for beginners who absolutely will need to debug.

Again, I agree completely with your opinion, but to many people cramming the board in as small a box as possible is part of the fun/challenge. For personal use, the extra difficulties of servicing are not as big of a deal. Really I guess I was just trying to get a feel for about what proportion of people have been bitten by the 1590A bug. 

Good for experimenters, but I've had remarkably few takers on the boards I've set up for modularity.

That's a shame, but thanks for the tip. The inspiration behind this idea was the forum vibe. Personally I would love to see more projects set up with such a clear and thorough guide and that degree of "tweakability".

The degree of split on that last question is definitely interesting.

[Electron Tornado]

Here's some input from someone who is an amateur, hobbyist, with some building experience. For scratch built pedals I tend to do my own layouts and etch my own PCBs.

One important point is that any layout or PCB must be both practical and easy to use. With that....

- Don't make spacing crammed and tiny. To make these most useful, remember, these should be useable by beginners with little to no experience. I know some people like the challenge of fitting something into a small enclosure. OK, if they want that challenge, let them come up with a suitable layout.

- Parts should be layed out flat, for the same reasons R.G. mentioned.

- Pads for off board wiring should come to a single edge, AND be large enough for easy soldering.

- Modularity would be great in some cases, but just a decent basic layout is fine. Make it easy to build and test or troubleshoot. If I want to mod something I usually make a daughter board.

- PCB standoffs are the only way to go. I agree. I do not like board mounted LEDs, pots, switches, signal, or power jacks. In my opinion, those will just lead to an eventual failure of a solder joint, or damage to the PCB, both of which will be very frustrating for hobbyists. This also limits my options for an enclosure, external control layout, and ability to modify later.

- One final point - I see a lot of PCBs with tiny, thin traces and thin solder pads. Then I hear people who have trouble with pads or traces lifting off the board. When I build a PCB I only l remove as little copper as needed. I feel it gives me a more robust trace with stronger pads and enough space in case I make a mistake drilling, or need to drill something extra for a mod. Don't use ribbon thin traces and pads. Not everyone who might use your layouts is going to have great soldering skills.


Hope this helps.

[Kearns892]

Here's some input from someone who is an amateur, hobbyist, with some building experience.

Hey, R.G. may be the pedal design guru (and for that his input is greatly appreciated); however, I am designing for the amateur, DIY community and because of that input from guys like you is also great. I'll be sure to keep your input in mind when designing these boards.


There is still a huge split in preference for mounting methods at the moment and preferences regarding the LED are still fairly varied, so I still need more respondents in the Survey!

[Kearns892]

Thanks all for your responses. Since responses have tapered off I decided I would post the results to anyone interested.

Q1. On your PCBs, which do you prefer?
Winner: No Preference
Margin: 15%

Q2. On your PCBs, how do you like your resistors mounted?
Winner: Flat
Margin: 66%

Q3. On your PCBs, how do you like your board mounted?
Winner?: Toss up between standoffs and board mounted pots.
Currently Standoffs are leading but only by a 1 vote margin!

Q4. On your PCBs, what status indicator LED options do you like to have?
Winner: No Status LED or Completely Off-Board LED wiring
Margin: 22%

Q5. How do you prefer your PCBs?
Winner: Compact and Well Laid Out (More Spacious/ Neater Layout, Off-Board Wiring Pads at Edge, etc.)
Margin: 37%
(For those interested Modular and Tiny both has approximately the same number of votes.)


Keep in mind this poll was taken using methods of convenience and was not scientifically conducted and contained only 30 respondents, so I am sure there is a degree of bias. However, I do feel like these results do say a lot about the preferences in this community.

While I do not intend to update the results here, I have left the poll open, so if you want to respond still please do!

Thanks for the input everyone

[bluesman1218]

Well, Jordan, since business results always boil down to Supply & Demand, you will find out the real preferences when folks vote with their wallets. Perhaps a question you should ask is what would make you buy my PCB instead of someone elses?

My opinion, from a business perspective, not techie, is that there are several folks offering boards and several of them seem to be fairly successful (yes it's a subjective term based on how one measures "success"). My question to you is this, are any of them doing things drastically different from one another? I haven't researched this and don't know the answer, don't need to.  But I have seen many of them praised quite often here.

If you are trying to differentiate your product, that takes you in one direction. If not, what will cause someone to buy your board over someone else's?

Please understand that am not casting any aspersions on your project, or how you are going about it. I am just offering a few thoughts based on 30+ years of fairly successful business experience AND how I make my buying decisions.

[Hides-His-Eyes]

Uh, I think he said these were for him to do and provide the artwork for people to use, not for him to sell.

[bluesman1218]

Uh, I think he said these were for him to do and provide the artwork for people to use, not for him to sell.

Got it. Only had a few minutes to check in and didn't -re-read the whole thread

[CodeMonk]

when practical, I prefer to mount my PCB's on the stomp switch.

[Kearns892]

@Bluesman
I plan on providing the artwork and hopefully a project PDF for a few designs. I think there is so much good information on this forum, but a forum is just not the best way to archive info. Hopefully I will be able to provide that info in an easy to access way.

@CodeMonk
From an Engineering standpoint, that puts unneeded stress on the PCB. While its probably fine for home use, the main reason I didn't list that as an option was it constrains the way the box can be laid out which may turn some people off to it. It may be a good idea for personal layouts, but for something a lot of people are going to use, maybe not. Thanks for the suggestion though.

[merlinb]

I do like board mounted LEDs (and other board-mounted components where possible- such as the DC jack which can be a great space saver and an easy way to locate the board in the enclosure). I don't see why a board mounted LED would be a problem- you could just run flying leads to the same pads if you want to mount the LED some other way.

Board width is important to me. Most people build in Hammond or equivalent enclosures. The two common internal widths being 58mm or 115mm. I hate it when people design boards of random width that either require you to use a bigger enclosure that you could have avoided, or else leave big gaps around the edge of the board that could have been used for standoff mounting.

[CodeMonk]

@Bluesman
I plan on providing the artwork and hopefully a project PDF for a few designs. I think there is so much good information on this forum, but a forum is just not the best way to archive info. Hopefully I will be able to provide that info in an easy to access way.

@CodeMonk
From an Engineering standpoint, that puts unneeded stress on the PCB. While its probably fine for home use, the main reason I didn't list that as an option was it constrains the way the box can be laid out which may turn some people off to it. It may be a good idea for personal layouts, but for something a lot of people are going to use, maybe not. Thanks for the suggestion though.

How does it stress the PCB?
Not being an ass here, but with the switch mounted securely on the enclosure, and proper strain relief on any wires, I don't understand how that stresses the board.
But for the record, I've only done it on a few builds.
At the very least, I like to have the LED and switch mounted on the same board. But not always.

[Steve Mavronis]

- PCB standoffs are the only way to go. I agree. I do not like board mounted LEDs, pots, switches, signal, or power jacks. In my opinion, those will just lead to an eventual failure of a solder joint, or damage to the PCB, both of which will be very frustrating for hobbyists. This also limits my options for an enclosure, external control layout, and ability to modify later.

I don't agree that using board monted pots lead to evential failure of their solder joints. As long as you take care with your shaft center spacing on your PCB design and case holes they go through so there is no twisting, they can be the cleanest and most professional way to mount a PCB. Physical stress is basically non-existent using finger rotation on the knobs and 'only' real consideration is you have to work your PCB layout design 'around' fixed solder pad locations (near the board edge) but I think the end result is really pleasing and worth the extra effort:



Also on these two different board designs, one uses all vertical resistors and the other uses all flat resistors because of the overall amount and density of parts is a 2:1 ratio between them, using the same 2"x1.7" board size.

[Kearns892]

How does it stress the PCB?
Not being an ass here, but with the switch mounted securely on the enclosure, and proper strain relief on any wires, I don't understand how that stresses the board.
But for the record, I've only done it on a few builds.
At the very least, I like to have the LED and switch mounted on the same board. But not always.

Like I said, for personal (and most non-abusive) uses, its probably fine. However, having the switch with other panel mounted parts connected to the PCB can lead to stress that can eventually crack the board as the switch moves slightly. I'm not an expert, I am just echoing what others have discussed on the forum. If you search I am sure you will find a more well articulated explanation from someone much smarter than me. 

[Kearns892]

I do like board mounted LEDs (and other board-mounted components where possible- such as the DC jack which can be a great space saver and an easy way to locate the board in the enclosure). I don't see why a board mounted LED would be a problem- you could just run flying leads to the same pads if you want to mount the LED some other way.

Board width is important to me. Most people build in Hammond or equivalent enclosures. The two common internal widths being 58mm or 115mm. I hate it when people design boards of random width that either require you to use a bigger enclosure that you could have avoided, or else leave big gaps around the edge of the board that could have been used for standoff mounting.

Your point about the width of the board is a good one.  I have seen many projects built that don't really keep in mind the boxes most DIYers use which is frustrating.
You bring up a good point about the LED pads. In cases where I can do that without major sacrifices in board layout it sounds like something to consider...

[R.G.]

Your point about the width of the board is a good one.  I have seen many projects built that don't really keep in mind the boxes most DIYers use which is frustrating.

It's more than a good point. It's a crucial one, in that **the FIRST thing to decide about a PCB layout is what constraints the physical layout puts on it**. That is, the box, the mounting style, where the on-board and off-board controls go, where the wires come out, and so on. These need to be the first things done to a PCB, before you ever put the first component onto the PCB. Otherwise, you have to hope the eventual user can just buy a box big enough for this not to matter. This is right out of "PCB Layout For Musical Effects". These things go onto the PCB layout first, and get locked into position (if your layout software lets you do that) so you don't accidentally move something that will make the mechanics not fit.

[Kearns892]

I have been wanting to get your book for some time R.G. Is small bear the only place that carries it?

[Scruffie]

Your point about the width of the board is a good one.  I have seen many projects built that don't really keep in mind the boxes most DIYers use which is frustrating.
It's more than a good point. It's a crucial one, in that **the FIRST thing to decide about a PCB layout is what constraints the physical layout puts on it**. That is, the box, the mounting style, where the on-board and off-board controls go, where the wires come out, and so on. These need to be the first things done to a PCB, before you ever put the first component onto the PCB. Otherwise, you have to hope the eventual user can just buy a box big enough for this not to matter. This is right out of "PCB Layout For Musical Effects". These things go onto the PCB layout first, and get locked into position (if your layout software lets you do that) so you don't accidentally move something that will make the mechanics not fit.

I have no idea if R.Gs morals appeal to my board layouts but I make them from a builders point of view, I also always use board mounted pots, not cause of stabilitiy but cause i'm so sick of off board wiring, boards without put me off  

But I do choose the pot and pad layouts before I start placing components, I think my Big Muff tone stack Dr Boogey is a decent layout, after building it infact there's too much space but it's spaced nicely and i'll learn as I go.

I'm very against stand up resistors and I think with time, any layout can work, my reasoning against is pure lazyness though