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Noob startup component stock

Started by Blisterfingers, December 20, 2018, 10:01:49 AM

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Blisterfingers

Hi all,
First post here after my introduction.
I'm looking to build up some component stock and have been doing lots of reading and searching.
I tried to analyse the Bills of Material for a bunch of different commercially available PCBs, starting with madbean, and have managed to incorporate lists for 23 circuits into an Excel sheet (happy to share if anyone wants a copy).

After a bit of data cleansing, the table below lists the values of most components and I've highlighted some of the most common ones.

madbean BOM analysis


   
      
      
      
      
      
      
   
      
      
ComponentType/RatingValues
CapacitorCeramic/MLCC4.7pF, 10pF, 15pF, 22pF, 27pF, 33pF, 47pF, 68pF, 100pF, 120pF, 150pF, 180pF, 220pF, 270pF, 330pF, 390pF, 470pF, 560pF, 820pF
CapacitorFilm1nF, 2.2nF, 3.3nF, 4.7nF, 6.8nF, 10nF, 15nF, 22nF, 39nF, 47nF, 100nF, 220nF, 1uF
CapacitorElectrolytic1uF, 2.2uF, 4.7uF, 10uF, 22uF, 47uF, 100uF
ResistorCarbon/Metal Film 1/4W, 1/8W22, 47, 100, 220, 330, 470, 560, 1k, 1.5k, 1.8k, 2k, 2.4k, 2.7k, 3.3k, 3.9k, 4.7k, 5.6k, 6.8k, 7.5k, 10k, 12k, 15k, 18k, 20k, 22k, 27k, 33k, 39k, 47k, 56k, 68k, 82k, 100k, 120k, 150k, 220k, 390k, 470k, 1M, 2.2M, 3.9M, 4.7M, 10M
DiodeVarious1n34a, 1N4001, 1N5817, 1n914, BAT46, 1n270, 1N4002
PotsVarious 10kA, 100kA, 250kA, 500kA, 1kB, 10kB, 25kB, 50kB, 100kB, 500kB, 100kB-Dual, 1kC, 5kC, 100kC, 500kC, 1MA, 1MC
TrimpotBourns 3362P1k, 5k, 10k, 20k, 25k, 50k, 100k, 250k, 500k
ICVarious4558, BTDR-3, LM1458, LM308, LM386, LT1054, PT2399, TC1044SCPA, TL062, TL072, TL074

So, here's my stock acquisition plan to set me up with the basics but without spending too much up front.

Resistors:
Capacitors (10 of each value):

  • Ceramics - MLCC only. TDK or Murata CG0 – 4.7-820pF.
  • Film – EPCOS or WIMA box caps, 5mm lead spacing. 1nF-1uF.
  • Electros – Panasonic, Nichicon or Lelon. 1uF-100uF. 5mm height where possible. Min 25V, 1,000 hour rated,1.5-2.5mm lead spacing.
Others:

  • Diodes & LEDs – assorted pack from Smallbear or Tayda.
  • ICs – DIP8 sockets. Will buy ICs per-project to start with.
  • Pots & trimmers – Per-project to start with.
  • Audio Jacks – per project to start with but buy a few extras each time to build up stock.
  • Enclosures & knobs – Per-project to start with.
  • Power – Battery snaps and power jacks.
  • Transistors – As needed. Ge from known good sources like Smallbear.

I'm familiar with most of the common suppliers and have bought stuff from Digi-Key and Mouser in the past.

Is this a good starting point or have I over-analysed things!
Very happy to hear feedback and suggestions on values, brands, missing items etc.



mjg

I find it's worth getting extras of TL072, 1n5817, 1n4148 (914 alternative) as they are in almost everything.   The 100kA pots are in a heap of projects too, but you never know if the board will be 16mm or 9mm pots. 

Jacks and stomp switches will always be needed, so stock up on them. 

Your list looks very organised - don't worry about the over analysis, we all do that here.  ;)

Aentons

#2
The real anguish comes when you have 95% of the parts for a project and have to order $1 worth of parts and have to justify $5-10 shipping. It especially bites when you find yourself needing to order the remaining items from more than one supplier and have to pay shipping from each.

Also, Learn to use the filters at Mouser. The Xicon metal film resistors are the way to go. Mouser part# 271-100-RC



sonnyboy27

Quote from: Aentons on December 20, 2018, 03:25:49 PM
The real anguish comes when you have 95% of the parts for a project and have to order $1 worth of parts and have to justify $5-10 shipping. It especially bites when you find yourself needing to order the remaining items from more than one supplier and have to pay shipping from each.

Also, Learn to use the filters at Mouser. The Xicon metal film resistors are the way to go. Mouser part# 271-100-RC

That's when you order from Arrow  ;)

somnif

Yeah Arrow.com is amazing. The search interface is a pain, and the selection is often random as hell, but free overnight shipping with no minimum order size is mind bogglingly phenomenal.

Plus they'll send you a lifetime supply of cardboard for a pack of resistors.

I'd also suggest Tayda.com . They're dirt cheap and shipping is quick, and while quality isn't exactly stellar at times, for things like resistors and caps they're my go-to. I wouldn't use their semiconductors in commercial grade products, but good enough for hobby usage.

dan.schumaker

Quote from: somnif on December 20, 2018, 04:16:29 PM
Yeah Arrow.com is amazing. The search interface is a pain, and the selection is often random as hell, but free overnight shipping with no minimum order size is mind bogglingly phenomenal.

Plus they'll send you a lifetime supply of cardboard for a pack of resistors.

I'd also suggest Tayda.com . They're dirt cheap and shipping is quick, and while quality isn't exactly stellar at times, for things like resistors and caps they're my go-to. I wouldn't use their semiconductors in commercial grade products, but good enough for hobby usage.

Arrow has also been awesome with supplying boxes for wrapping Christmas presents.... just saying  :D

Bio77

Figuring out how to source parts is what first led me to the Mad Bean site.  It sounds like you are already addicted to the hobby, so, building up a parts stash is a good idea.  I would recommend picking two or three PCB projects and ordering all the parts with plenty of extras to complete those projects.  This what I have been doing and It works well.  Now when I'm planning my future projects I just create a parts list and compare it to my inventory.  I'm usually in need of a few parts and I order extra of those too (the exception being rarer stuff and pots).

I typically buy, pots, enclosures, resistors, LEDs, diodes, some transistors, and knobs from Tayda.
Caps and popular ICs from one of the big sites (mouser, arrow, newark).  With these buying in quantity helps to keep the price down (electros especially).
ICs, most transistors, and the weird stuff at small bear.
Foot switches, toggle switches, jacks at BLMS.

Blisterfingers

Thanks all for the advice - living in the Southern Hemisphere, shipping costs often make small purchases uneconomic. It's usually worth buying enough to qualify for free shipping from Mouser/Digi-key/element14 etc.

I already knew about Tayda, but arrow.com is new to me and I've added it to my supplier bookmarks.

mjg

You're in NZ?  Do you have RS Components there?  That's who I use in Australia a lot, for last minute orders with free shipping.  Sometimes you need to order a minimum of 10 resistors, etc.

Element 14 is OK, but shipping costs unless you spend $40 or something. 

DIYGP (in the banner links above) is great, based in Melbourne, not sure how much the shipping would be to NZ. 

stevie1556

Quote from: Aentons on December 20, 2018, 03:25:49 PM
The real anguish comes when you have 95% of the parts for a project and have to order $1 worth of parts and have to justify $5-10 shipping. It especially bites when you find yourself needing to order the remaining items from more than one supplier and have to pay shipping from each.

Also, Learn to use the filters at Mouser. The Xicon metal film resistors are the way to go. Mouser part# 271-100-RC
Every. F**king. Time.

Did it 3 times, or was it 4 times, just on my current build. Missed an all important transistor off on the last build. One of the ICs off of a build before that. I've probably spent more on postage then I have components for quite a few builds. So on that note, definitely stock up! As said above, Tayda is a great way to get cheap resistors, capacitors and pots.

Welcome to the hobby though, it's so satisfying when you get a new pedal working straight away! :)

Sent from my SM-G955F using Tapatalk

ahiddentableau

Welcome to the forum.

Looking at your first post on this, I'm mostly struck by the fact that you've done your homework.  You read enough to know what kinds of parts are generally endorsed by the community and gone through enough BOMs to get a great sense of what you're likely to use and use with good results.  So if you're a newbie, keep this up and you're not gonna be one for very long.  You didn't just do a good job.  You basically hit it out of the park.

mjg pointed out the only obvious things your list missed.  But the only thing I'd add is for those of us who don't live in the USA it often makes sense to bite the bullet and buy a bit more upfront in order to avoid/minimize shipping costs.  So if you're reasonably sure you're going to build a significant number of projects, you might want to buy jacks or ICs 10-20 at a time.  You can get bulk discounts and the shipping savings really add up quick.

Netnnk

You can also substitute many parts. There are guides for changing the value of pots, and you can combine capacitors and resistors in series or parallel to make up whatever value you need.

Many of the diodes and Op Amps and interchangeable, and good enough to test if your project is working.

alanp

Quote from: Netnnk on December 23, 2018, 10:51:26 PM
You can also substitute many parts. There are guides for changing the value of pots, and you can combine capacitors and resistors in series or parallel to make up whatever value you need.

https://www.diystompboxes.com/analogalchemy/emh/emh.html

Bookmark this link. Damn useful when substituting parts.
"A man is not dead while his name is still spoken."
- Terry Pratchett
My OSHpark shared projects
My website

Willybomb


Blisterfingers

Quote from: mjg on December 20, 2018, 09:20:43 PM
You're in NZ?  Do you have RS Components there?  That's who I use in Australia a lot, for last minute orders with free shipping.  Sometimes you need to order a minimum of 10 resistors, etc.

Element 14 is OK, but shipping costs unless you spend $40 or something. 

DIYGP (in the banner links above) is great, based in Melbourne, not sure how much the shipping would be to NZ.
Thanks for the link. I used to buy stuff from RS in pre-Internet times but had forgotten about them. Free shipping is a godsend!