Author Topic: From no parts to decent stockpile, best approach?  (Read 736450 times)

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Offline alexanderbrevigTopic starter

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From no parts to decent stockpile, best approach?
« on: August 18, 2015, 10:13:00 pm »
Hi again guys, and welcome to the next installment of beginners (played by me) asking the wise and omniscient professionals (that's you) stupid questions.

I'm a software developer trying to get into EE and circumventing 10 years of gathering parts and test equipment.
The first thing I did was build a workbench, and acquire the . Now onto the tedious part; components!

What is the easiest way to get a decent stockpile of components?

My main goal is to be able to prototype most ideas.

Is there something like the (now discontinued) Seeedstudio Open Parts Library but for everything?

I need resistors, caps, inductors, chokes, ferrites, crystals, TVSs, fuses, diodes/zeners/bridge rectifs, transistors, leds, triacs, voltregs, op amps, audio amps, logic ics, optoelectronics, some sensors, wire and connectors.

I'm tempted to make a 'reel to plastic bag' robot and make these kits myself if they don't exist.

Any ideas and pointers are much appreciated!
 
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Offline fivefish

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Re: From no parts to decent stockpile, best approach?
« Reply #1 on: August 18, 2015, 11:13:48 pm »
When buying components, (resistors, caps, etc), buy 100pcs of the part. Usually, it's much cheaper per piece than buying 1-2 pcs. only.
Also check out eBay for "set kits"... resistor kit, ceramic caps kit, diode kit, zener kit... you get lots of values (the whole range) with 10-20 pcs for each value.
Electrolytic kits are more expensive, it's better to just order a few extras when you order parts for a specific project. Over time, you'll build a good stock.
If you can afford to wait, you can buy specific parts for a project from eBay (China). Slow shipping though so plan ahead.
If you don't mind re-using parts, salvage parts from broken equipment.
Build a small decade resistor box (using the up/down switch and some smd resistors). Usually in a project, a few parts will be critical in value and if you don't have the right value, a decade resistor box will help in a pinch.
Organize organize organize -- nothing is worse than knowing you have the part, but can't find it in your stockpile.
 
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Re: From no parts to decent stockpile, best approach?
« Reply #2 on: August 18, 2015, 11:28:25 pm »
Just wanted to comment - hell of a nice workbench there!  :-+
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Offline michaeliv

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Re: From no parts to decent stockpile, best approach?
« Reply #3 on: August 19, 2015, 01:18:13 am »
Also check out eBay for "set kits"... resistor kit, ceramic caps kit, diode kit, zener kit...
I would recommend AliExpress instead of eBay if you are looking for the lowest price and can wait a bit more ( In my experience electronic components are cheaper ~20-50% on AliExpress than eBay, there's a bigger variety, but AliExpress sellers do take time to ship out items, some ship immediately, some after 1-2 weeks).
 

Offline tooki

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Re: From no parts to decent stockpile, best approach?
« Reply #4 on: August 19, 2015, 01:32:34 am »
I wouldn't recommend trying. You will either have too many of things you will never use or not enough for the next project. They will take up space and time in organising them or even more time if you don't organise them.
Get a resistor and capacitor kit for breadboarding. Buy a few extra parts of stuff you are using. Either they will suit as spares or they fit the circuits you are interested in.

Have a couple of projects in mind and you can order parts for the next one whilst working on the current one.

The real problem is not having enough parts, it is having too many. How much is too much? If you can't carry it to the rubbish bin in one trip you have too much.

Quoted for truth. The only things I stockpile are LEDs, resistors, a basic set of caps, a few basic transistors and diodes, and a bunch of headers and matching connectors. Other than that, I buy as needed. I just haven't found it useful to stockpile components I may or may not need. (It helps that the main components company in Switzerland, Distrelec, delivers next-day, so if I'm really in a pinch I can get it the next day -- or order online and pick up in person.)
 
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Offline rdl

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Re: From no parts to decent stockpile, best approach?
« Reply #5 on: August 19, 2015, 02:38:28 am »
Yeah, don't think you have to buy a bunch of parts right off just to have inventory. Maybe a resistor kit and a kit of film caps, maybe 5-10 each of common values of electrolytic less than 500uf (you won't need many different values of electros). But anytime you have to order parts, buy a bunch. For cheap parts buy a hundred, more expensive such as logic, micros, regulators etc, try to at least go up to the first price break (usually 10 but sometimes 25).
 

Offline matseng

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Re: From no parts to decent stockpile, best approach?
« Reply #6 on: August 19, 2015, 03:21:59 am »
Every now and then I pick up some cheap resistors and caps kits just to stock up on some uncommon values I've depleted.  Then I get full reels (for smd) or ammo boxes (for thruhole resistors) of the more commonly used parts.

And I always purchase *a lot* more of the a bit more specialized parts (ICs, power fets) than I actually need, because If I need them today I most likely will use them again in the future.

I also tend to purchase bulk from Taobao for stuffs like header pins, tactile push buttons, plain jellybean indicator LEDs and such.  Like instead of getting 10 pcs of a pushbutton from Element14/Farnell I can get a bag of 1000 of them from Taobao.  Same thing with diffused 3mm LEDs - I can get a bag of 1000 for a few dollars - and they will last a few years - actually the leads on them will be corroded and ugly before they are used up for prototyping and general mucking around.
 

Offline pickle9000

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Re: From no parts to decent stockpile, best approach?
« Reply #7 on: August 19, 2015, 03:31:28 am »
Order 100 bucks worth every time you order to make the shipping worthwhile. When hitting digikey, farnell / whomever the trick is to keep it down to 100 bucks. 
 
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Offline fivefish

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Re: From no parts to decent stockpile, best approach?
« Reply #8 on: August 19, 2015, 05:54:12 am »
Sometimes you just need jelly bean parts in your lab... 2n3904/2n3906, some 2n3055/mj2955 or equivalents... some n- and p-channel mosfets, some SCRs, to use for prototyping.

Then you can check out performance of your project and make a determination (ooops, need larger power dissipation, or higher hfe, or higher voltage rating) and you go buy that part specifically. (and make sure to order several extras, in case your part becomes damage during experimentation, or for future use).

But at least you've already tried your prototype and know it works.
 

Offline tooki

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Re: From no parts to decent stockpile, best approach?
« Reply #9 on: August 19, 2015, 09:29:27 am »
And I always purchase *a lot* more of the a bit more specialized parts (ICs, power fets) than I actually need, because If I need them today I most likely will use them again in the future.
Translation: Have extras on hand to replace the ones you fry during experimentation.  ;D :-/O

P.S. I think someone needs to create a "magic smoke" smiley.
 
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Offline alexanderbrevigTopic starter

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Re: From no parts to decent stockpile, best approach?
« Reply #10 on: August 19, 2015, 09:56:20 am »
Thanks guys :) I know the convention is to buy for each project and then buy a bit more than needed.

Basically you give me two advices; do not buy so you end up with too much, but buy more than you need. I understand the argument that when you buy because you need then you are likely to need that part again.

I will probably end up bying kits for resistors, caps, transistors and diodes, and then make a order with some specific parts as well.

My main goal is to not be hindered when I want to test something, as in - I want to have most "jelly bean" parts on hand.


I will continue to look around for good kits...
Do you think it would be a market for a "no parts to prototype stockpile" kit?
 

Offline matseng

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Re: From no parts to decent stockpile, best approach?
« Reply #11 on: August 19, 2015, 10:32:56 am »
And I always purchase *a lot* more of the a bit more specialized parts (ICs, power fets) than I actually need, because If I need them today I most likely will use them again in the future.
Translation: Have extras on hand to replace the ones you fry during experimentation.  ;D :-/O

P.S. I think someone needs to create a "magic smoke" smiley.
And I tend to not use sockets for DIP parts so I can't really re-use them for the next project. And the same goes for SMD parts of course....

And since resistors and jellybean caps and transistors like the BC547 and 2N2222's costs next to nothing I usually just rip them out of my solderless breadboards and shove them into a mixed junkbox that I give away every now and then to school kids with a limited budget for parts.  For me it's too tedious to straighten out and sort the parts into their proper places agin. ^_^
« Last Edit: August 19, 2015, 10:50:53 am by matseng »
 

Offline JoeN

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Re: From no parts to decent stockpile, best approach?
« Reply #12 on: August 19, 2015, 10:41:10 am »
Sample early, sample often.   :box:

Didn't your mom tell you to always cut away from yourself?   Please post the video where you slice your other hand open someday. :rant:
« Last Edit: August 19, 2015, 10:43:21 am by JoeN »
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Offline Deathwish

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Re: From no parts to decent stockpile, best approach?
« Reply #13 on: August 19, 2015, 10:51:52 am »
An idea for you, put a set of long thin drawers under the shelf you put your rigol kit on and maybe put your scope tips and spare probes in them , manuals , etc.
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Offline JoeN

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Re: From no parts to decent stockpile, best approach?
« Reply #14 on: August 19, 2015, 11:08:43 am »
My main goal is to not be hindered when I want to test something, as in - I want to have most "jelly bean" parts on hand.


I will continue to look around for good kits...
Do you think it would be a market for a "no parts to prototype stockpile" kit?

This idea of having a large stock of parts was borne out of the era when getting parts was way harder than a next day delivery via an online distributor.  It really just isn't necessary anymore. By all means accumulate part s as you find them but building up a parts inventory is so last century. Every parts collection is 99% destined to never get used.

You'll start out excited that you have all this stuff to do things with and then years down the track you will dispair at the things you don't have time to do. You can't win.

I sort of agree and sort of don't.  Having kits of resistors and capacitors is just a must.  You don't want to have to stop prototyping and wait even 24 hours for a part, especially when it will cost you $25 to overnight a 50 cent crystal or some caps.  That would make me unhappy, so I make sure it doesn't.

Kits to have:

1/4 watt through hole resistor kit.
0805 or 0603 resistor kit.
Through-hole ceramic caps kit  A few hundred of .01uF, .1uF and 1uF are not bad to have because your will use those everywhere and those are very cheap.
Through hole smaller value electrolytic caps kit.
0805 or 0603 SMT capacitor kit.
At least a few hundred 5mm LEDs, a few different colors, red, green, white are probably the best.
At least a few dozen 16Mhz and 20Mhz crystals and a kit of a few each of different values doesn't hurt.
At least a few dozen adjustable and 5V regulators.  Again, a small kit of different values doesn't hurt.
Transistors:  100 each of 2N3904, 2N3906, 2N7000.  Jellybean parts.

You will know what other parts you end up using a lot.  For me it is ATMega328P-PU, ATTiny88, 74HC595, MAX7219 (cheap clone from eBay), certain connectors, hardware and project boards.

But samples are the best.  If you can, get some op amps, comparators, instrumentation amplifiers, 16/24 bit ADCs, 16 bit DACs, digipots, LED drivers, clocks, microcontrollers, etc.  Those are nice to have in the bin.

I think kits like these are just good deals:

http://www.ebay.com/itm/2000-pcs-Assorted-1-4W-0-25W-5-Through-Hole-Carbon-Film-Resistor-Kit-0-10Mohm-/111275963196
http://www.ebay.com/itm/1000pcs-50-Values-50V-Ceramic-Capacitor-Assorted-kit-Assortment-Set-Hot-Sale-/151128848522
http://www.ebay.com/itm/2300pcs-SMD-0805-0-10M-50value-Resistor-2-2pf-1uf-40value-Capacitor-Kit-Set-/110941312626 
http://www.ebay.com/itm/1000Pcs-5MM-LED-Red-Yellow-Green-Blue-White-Round-led-diode-Mixed-Color-kit-/291197363177
« Last Edit: August 19, 2015, 11:14:20 am by JoeN »
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Offline matseng

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Re: From no parts to decent stockpile, best approach?
« Reply #15 on: August 19, 2015, 11:11:57 am »
This idea of having a large stock of parts was borne out of the era when getting parts was way harder than a next day delivery via an online distributor.  It really just isn't necessary anymore. By all means accumulate part s as you find them but building up a parts inventory is so last century. Every parts collection is 99% destined to never get used.
That has some truth to it.  But even if I have free overnight courier shipping from Element14 Singapore to my doorstep in Malaysia I still prefer to just swivel my chair around and pick out the parts I need from the shelves behind me.  It's extremely irritating to discover that I have to stop tinkering for a day just because my box of bat54 Schottkys just ran out.  Or just being able to test 5 different stem heights of tactile switches to discover which height that fits best in the 3d printed enclosure.

When I'm in my second living place - Bangkok - I don't have access to overnighters. Stuff usually takes 3-4 days to arrive, then it starts to be really annoying. And unfortunately I just have a really small desk there - my main lab is in Malaysia where I have overflowed into a second room to the wife's dismay . :-)
 

Offline Deathwish

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Re: From no parts to decent stockpile, best approach?
« Reply #16 on: August 19, 2015, 11:12:54 am »
I have a number of different diodes, resistors , some caps, bridge rectifiers, voltage regs +5/9/12 -12v and lm317T / 337T as a must have set. Always bet a psu will play up somewhere
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Offline Chris C

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Re: From no parts to decent stockpile, best approach?
« Reply #17 on: August 19, 2015, 06:22:02 pm »
Organize organize organize -- nothing is worse than knowing you have the part, but can't find it in your stockpile.

I really want to stress this.  The more parts you have, the more critical it becomes.  Give some serious thought to your organizational system.  It may undergo many revisions, with each successive migration taking more time:

1) I started out with those common part organizers, the ones with lots of pull-out drawers, that can be partitioned in half.  They're ok for rapid access to a few parts, but each separate area tends to waste a lot of space.  And they don't travel well!  I took them in the car once, and they got tipped over.  What a mess.  Some drawers opened and parts flew out.  Some drawers got jammed by parts so badly I had to destroy the drawers to remove them.  Parts traveled surprisingly easily between drawers and partitions, getting mixed together.

2) Next system - Plano Stowaway #3600 series boxes.  The specific variety that can be partitioned in up to 24 areas per box.  Apparently not sold separately anymore, included only with a larger organizer that holds 4x boxes, which I also use; if interested, I can look up the model #.  These served me well, and still do.  They travel without issue.  Though each partitioned area may still waste a lot of space.  At some point I got a few hundred smaller hinged-top plastic boxes, cheap via surplus outlet, that fit well and further subdivided the space.  But eventually I ran out, and though I searched extensively, I couldn't find the same item.  All similar replacements didn't fit as well, and were much more expensive.  Also, when my parts collection grew, moving around partitions, boxes, and parts to keep similar items together became quite a chore.

3) I'm gradually migrating to use of a lot of Ziploc-style bags, of many different sizes, some quite small.  These waste virtually no space, if you press the air out before sealing.  Sometimes I don't get all the air out, so I typically poke a little hole in the bags to let the air escape, pressed out by the weight of other bags.  And I have a Brother label printer to make nice self-adhesive labels.
3a) For frequently-used parts, I still use the Plano 3600's.  For example, I have a 3600 for most resistors.  For 1/4W leaded, each partition holds a decade (0-9.9ohm, 10-99ohm, 100-999ohm, etc).  The individual values are kept in bags within the appropriate partition.  I have fewer 1/2W leaded, those get just a couple of partitions with bags.  Another partition for current measurement shunts.  A few partitions for trimmers.  And so on.
3b) For lesser-used or bulky parts, I use a nested bag system.  For example, I have a medium bag for diodes, containing smaller bags for switching, rectifier, fast recovery, varactor, and Schottky; and each of those containing tiny bags for each part # and value.  The medium "diode" bag goes into a Rubbermaid bin for "semiconductors", along with transistors and such (not including IC's, I have enough of those they get their own bin).  Power resistors and large potentiometers would take up too much room in the 3600's, so they all get bagged and binned.

It takes a while to collect many different parts for a project, but at least I always know exactly where those parts are.  The alternative is chaos and a lot more wasted time.

I will also warn against buying random part assortments where the parts are not already sorted/separated and clearly labelled.  No matter how incredibly cheap they may be.  You will put off sorting them.  When (if) you finally do, you will typically find lots of oddball parts and values, that you'll then feel obliged to spend time organizing when it will probably never benefit you.

I bought some SMD ceramic cap and resistor assortments from an Ebay seller.  Each value is on tape, and the value hand-written on the tape.  But not particularly legibly!  I don't regret it, but I had to spend some time relabeling them all, including testing those for which I was unsure.  If I had to do it again, I'd try to buy from a listing that includes a picture showing the seller's handwriting. ;)

For orders from traditional large distributors, I prefer Newark over Digikey/Mouser.  Not just because they're cheaper in general, but because they print part specs in a small square on the invoice, that can be cut out and taped onto something as a useful label.  Big time saver.  They used to include a separate sheet with the same info printed on actual peel-and-stick labels, but I haven't got that with my last few orders; either they stopped doing that, or they do it only for orders exceeding a certain size (my last few orders have been smaller).

Buy some panels of anti-static foam that you can cut down to size as needed.  And some anti-static Ziploc-style bags of various sizes.  You'll need them to repackage ICs and static sensitive discretes that you receive packaged in ways incompatible with your storage system.  Schottky diodes are static sensitive, unless they have an integrated guard ring, so when possible I get the latter to reduce special packaging and handling requirements.

Some useful "jellybean" ICs that I think everyone should have, whether you want them in DIP or SMD (or both) is up to you:
* LM393 (dual) and LM339 (quad) comparators (same specs per each comparator)
* LM358 (dual) and LM324 (quad) op-amps (same specs per each op-amp)
* TL084 quad JFET op-amp
* TL431 shunt regulator

Supplement with special case op-amps as needed.  I like to have a few rail-to-rail varieties on hand, MCP6002 is good for relatively slow signals, MCP6294 is faster; but they are by no means the only options or even clearly superior, they're just what I quickly picked to fill a possible need.  And in fact I've never actually needed them. ;)

For digital work, a variety of 74* series logic ICs may be handy.  In particular, the 74HC family, which seems most useful for interfacing to any other logic family, and isn't too expensive.  But there's still a lot of parts in that family, you'll have narrow it down to what you think you'll use.  If you get into MCUs, and use those with sufficient number of pins that you don't need to multiplex input/output signals, you may never need any of the 74*.

The KIS-3R33S is a tiny 3.3V 3A switching regulator module, available dirt cheap on Ebay and such.  Can be modified for other output voltages via external feedback resistor or modification.  I bought a few dozen of them for something like $0.20 each, love them, and use frequently whenever a switcher shows clear benefit over a linear reg.  Always put at least a 10uF ceramic or low-ESR electrolytic on the output to ensure stability; or if you want low switching noise, use a Pi filter (cap-inductor-cap).

I could go on and on.  You will always find yourself in need of something.  And in trying to prevent that, you will always buy a lot of stuff you will never end up using.  Plus your needs will change as time goes on.  Whenever you think of something you'd like to have, but don't need immediately, put it on a list.  Whenever you need something immediately, evaluate your list, and also order the items on the list you want most; feeling free to leave low-priority stuff on the list.  You may find some things stay on your list a long time, until you decide you really didn't want or need them after all.
« Last Edit: August 19, 2015, 06:27:49 pm by Chris C »
 
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Offline Kintekobo

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Re: From no parts to decent stockpile, best approach?
« Reply #18 on: August 19, 2015, 06:47:32 pm »
One of the best component buys I made was the RS Components resistor set. Not sure if they still sell them but it is incredibly useful especially when designing and you need to try lots of different values. I just wish that they had made a similar one for caps.
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Offline alexanderbrevigTopic starter

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Re: From no parts to decent stockpile, best approach?
« Reply #19 on: August 19, 2015, 07:07:19 pm »
An idea for you, put a set of long thin drawers under the shelf you put your rigol kit on and maybe put your scope tips and spare probes in them , manuals , etc.

That is an excellent idea!
I'm currently printing some holders for wires and probes but a shelf there for various tidbits would be awesome. Thanks :)
 

Offline john_p_wi

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Re: From no parts to decent stockpile, best approach?
« Reply #20 on: August 19, 2015, 07:17:15 pm »
Chris above has a lot of valid points.  I have been involved with electronics for something like 30 years and work on everything from 100 watt vacuum tube amps using high wattage leaded components to SDR radios using SMD components and micro processors.  Whenever I order anything I try to order a few extra pieces to meet the first price break, that being said, the true challenge will be organizing the components and remembering what you have.  My method seems to be similar to Chris's and I tend to group like components in small envelopes / storage containers then box the groups and shelve.  Additionally IF you order from places like mouser you can export a spread sheet of your order allowing you to build a simple inventory spread sheet so you don't continue to order, order, order.
 

Offline alexanderbrevigTopic starter

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Re: From no parts to decent stockpile, best approach?
« Reply #21 on: August 19, 2015, 07:26:25 pm »
Awesome posts guys!

RE: stocking up, I live in Norway and because of all the taxation (and my extreme impatience when excited by a new idea) I want at least some stock on hand. I won't go crazy with it, but I want to be able to build some simple stuff and fix typical things when I want to :)

In terms of organization I use the drawers at work for proto and I've grown the habit of pulling them out entirely and place them on my desk. It's a ritual when I ponder and plan while I get the parts. Not the best way, but it's how I do it now. I label each drawer ex "47 R" which contains 4.7 47 470 4.7k in that drawer.

SMT parts I'll store in those 'ice cube trays' with lids, and some in air tight zip lock bags for MSD stuff. Most projects will buy MSD in 'exact' quantities so I don't get popcorn when reflowing...

Thank you @JoeN for concrete suggestions! They are added to my excel sheet (I'm not usually this ... pedantic but I'm having fun with this. Might as well as my hopes for a complete stockpile kit seems hopeless (need to keep my spirits up).

@john_p_wi Keeping inventory seems like a really nice idea! Do you know if there is a tool (there's an app...) for that? The software developer in me awoke ;)
 

Offline Chris C

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Re: From no parts to decent stockpile, best approach?
« Reply #22 on: August 19, 2015, 07:31:24 pm »
One of the best component buys I made was the RS Components resistor set. Not sure if they still sell them but it is incredibly useful especially when designing and you need to try lots of different values. I just wish that they had made a similar one for caps.

Sets like those seem nice at first glance.  But I've always avoided them for two reasons:

1) They're pricey, mostly due to including their own custom organizer.
2) What happens when you also want to stock a value not included in the original set?  No place to add it in an organizer like that.  So you're stuck with keeping two organizers - theirs and one of your own.  And every time you check their organizer, then find you have to check the other, you will wish you had all the resistors together.  Eventually the series of small frustrations may add up enough that you decide to consolidate, and then their organizer (and the extra money paid for it) is wasted.

It looks like RS' current offering is different, being based on pages that fit in a three-ring binder, each containing 24x pockets.  That might be expandable.  Still rather expensive.  I've spoken to a lot of people who use cheaper DIY versions, using trading card holder pages if I remember correctly.  Though I've never used that system either.  The first and natural tendency is to keep resistors in ascending order without gaps, but then when you go to insert a new value, I'd imagine shifting EVERY component and label following it is time consuming!  Worse if you permanently affixed labels, or wrote them on with a Sharpie.  It's better if you leave gaps to minimize how many components need to be moved.  But leave too few, and you'll still sometimes have to shift a lot of stuff.  Leave too many and it's inefficient, and those binder pages aren't exactly cheap either.  I considered this system, but found myself indecisive how best to set it up, until I abandoned the idea for my current system instead which never requires shifting.  Others might be perfectly happy with it though, there's no one-size-fits-all solution.
 

Offline Chris C

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Re: From no parts to decent stockpile, best approach?
« Reply #23 on: August 19, 2015, 07:50:55 pm »
Keeping inventory seems like a really nice idea!

It is.  I don't keep an exact count of how many of each component I have on hand.  But being able to pull up what components I have is really nice.

For example, I'm designing a final PCB, for something I earlier prototyped using through-hole components.  But on the PCB, I'm using SMD components.  I'm adding a cap to the layout.  I *know* I have the cap in stock, as it's a common value.  But are the SMD 10uF ceramic caps I have 0604 or 0805 footprint at the required voltage?  Darn, I can't remember, and the prototype next to me is through-hole; so I'll have to go look through my SMD parts.  Repeat many, many times, unless you have a database. ;)

When I go to build the PCB, then I pull the actual part.  And if I notice I'm running low on that cap, I add it to the list for my next order.

For the inventory, I just use a general-purpose database.  Microsoft Access, it's a familiar program, as I used to do development in it.  Not sure what's out there in terms of programs dedicated to this task.
« Last Edit: August 19, 2015, 07:52:48 pm by Chris C »
 

Offline rx8pilot

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Re: From no parts to decent stockpile, best approach?
« Reply #24 on: August 19, 2015, 07:53:09 pm »
My approach, starting about 2 years ago was to get only resistors and capacitors in 0805 SMT kits. They were from DigiKey and I got about 250 of nearly all the 1% values and a much smaller selection of caps since they have so many more specs to consider. I went mainly with 50v for the small ones and 25v as they got higher. Tried to stick with X7R when possible. The reason for the 1% and X7R was that I did not want a poor performing cap  in-between resistor to slow me down. They are so cheap that it was not so bad and I have been very happy having a big variety.

For other components, I could not make any sense out of random buys. When I did a new project, I always buy alternates and extras that get added to the collection in the end. After two years, I have a solid stash of useful parts that I am already familiar with and have probably used before. I have examples of a few hundred types of parts to get me through my late night ideas.

How challenging is it for you to have access to parts?
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