# How to choose component size?



## jjourard (Mar 18, 2020)

PedalPCB documentation is sparse to say the least.  I don't mind building an order at Mouser for example, but there are about 15 different sizes of a 47uF capacitor for example.  How can I determine which diameter and height capacitor to buy? I would have expected that the build document would specify what's going to fit on the board.   The build document has an image of the PCB, but it is not remotely the size of the real thing.
So what do you do?  Guess?  Buy and curse?  Wait for the board to arrive and then measure the lead spacing with a micrometer?


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## Nostradoomus (Mar 18, 2020)

There is some assumed knowledge for these builds. Don’t order blindly, there’s plenty of helpful folks here. Try a search for component sizing as it’s been explained pretty thoroughly before. (Not trying to be short with you!)


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## jjourard (Mar 18, 2020)

Sorry to report that the search returns two hits - my post and your answer.


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## Nostradoomus (Mar 18, 2020)

“Capacitor size” and  “lead spacing” will have good result


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## jjourard (Mar 18, 2020)

thanks!


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## Chuck D. Bones (Mar 19, 2020)

You can also try measuring either the actual board or a scaled picture of the PCB.  Not rocket science.


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## jjourard (Mar 19, 2020)

Thanks --
I was considering measuring the board for spacing but it is not actual size and there is no scale reference in the image such as an inch or cm indication to set the reduction percentage.
As it is, I just ordered capacitors with 5mm or 2.5mm lead spacing as available and standard 1/8 watt resistors.  If they don't line up, I'll bend the leads.
It's not brain surgery.


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## Nostradoomus (Mar 19, 2020)




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## Chuck D. Bones (Mar 19, 2020)

jjourard said:


> Thanks --
> I was considering measuring the board for spacing but it is not actual size and there is no scale reference in the image such as an inch or cm indication to set the reduction percentage.



Actually, there are scale references:  
1) The top of page 1 in the build docs gives the board dimensions.
2) Download the data sheet for any of the pots or ICs on the board, they give pin spacing dimensions.


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## Chuck D. Bones (Mar 19, 2020)

Nostradoomus said:


> View attachment 3491



Ricky!  He's like a National Hero where you live, eh?


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## Nostradoomus (Mar 19, 2020)

Chuck D. Bones said:


> Ricky!  He's like a National Hero where you live, eh?



Pretty much yeah. But right now Fred Durst is the hero we all didn’t know we needed.


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## jjourard (Mar 19, 2020)

Thanks for the 'procedure' method of extrapolating measurements.  I'm used to vendors that put a little more into the documentation so we don't have to reinvent the wheel every time, but now that I know what's normal here at pedalpcb, I won't have to be so baffled next time.
Cheers!


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## jjourard (Apr 3, 2020)

About halfway through the Unison build.  Not all parts were available at once, one thing yet to be bought is the mini toggle switch.  It's clear by the size of the solder pads that the idea is to solder it directly to the board, then have it be just the right height to reach the enclosure and show up outside the case.  Can anybody recommend a switch part number that we know has the right dimensions?  
TYIA


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## Chuck D. Bones (Apr 3, 2020)

Try these from BLMS.

Or these from Tayda.

Small Bear has good switches, but they are offline while NYC is in lockdown.

I prefer short lever switches, much less likely to get switched accidentally or broken.  Both vendors also have long lever switches.


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## jjourard (Apr 3, 2020)

Thank you!  I'm of the same mind re: short bat toggles.


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