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In school, I was told not to leave components in a breadboard for extended periods of time. However, this length of time was never quantified. The reasoning was that the contacts would eventually lose their "springiness"; at some point later in time, you'd be debugging issues with a circuit, only to find out that the contacts were bad.

I have no idea if this is really true, or if breadboards are now made so well that it's not an issue. I have some nice ones, but in the end they seem to use the same narrow white piece that everyone else uses.

I've got some prototypes put together that I don't want to take apart yet, and I also don't know when I'll get back to it. My mbed board has now taken a back seat to the Netduino that I just received. :)

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    \$\begingroup\$ How much is your time worth? If you're doing this for work, ask your manager if he'd rather have you spend an hour debugging bad contacts or just buy a new one. \$\endgroup\$ – Kevin Vermeer Jan 5 '11 at 17:19
  • \$\begingroup\$ @reemrevnivek Good comment, but how can you determine if a breadboard is bad unless you provide a constant supply of new breadboards and assume that they themselves aren't damaged? \$\endgroup\$ – AndrejaKo Jan 5 '11 at 17:27
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    \$\begingroup\$ @Andreja - I should have said "risk spending an hour". The only way I know to determine if it's good or not is to build a circuit that should work. If it doesn't work, there's either a problem with the circuit, your wiring, the components, or the breadboard itself. If the circuit works, the wiring is correct, and the components are good, then you've got bad contacts. Kinda labor-intensive. \$\endgroup\$ – Kevin Vermeer Jan 5 '11 at 17:49
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    \$\begingroup\$ I know some people who build breadboarded circuits into enclosures, and just use them indefinitely, rather than make a PCB. 15 years later, they still work. \$\endgroup\$ – Connor Wolf Jan 5 '11 at 23:28
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    \$\begingroup\$ This sounds like something that ought to be submitted to Mythbusters :) \$\endgroup\$ – XTL Jan 11 '11 at 18:11
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Here's a picture of a board which had some headers forced into it which were too large, damaging the contacts:

Bad board

The outer rows of the Sharpie'd area make intermittent contact, so we avoid the whole section. Notice that some of the numbers are rubbed off, and also notice the burnt spot at the top of the picture where something burned up.

The breadboard still has two other middle sections, and this section is only 20 rows tall, so that leaves 172 good rows. On a university budget, that doesn't merit replacing the board. If you are demonstrating breadboarded circuits to a client, you should probably replace the whole thing.

By the way, this board is at least 8 years old, and still works fine except for the indicated area. I've only been around it for three years, but no one has had any problems with it that I've heard of.

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  • \$\begingroup\$ that's a great suggestion -- using Sharpie to designate keep-out zones. I like it! \$\endgroup\$ – Dave Jan 5 '11 at 23:55
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I've never had any problems, and I've left components in the board for months.

Component leads seem to be quite a tight fit anyway, so whether it's springy or not I think it will make contact anyway.

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  • \$\begingroup\$ how about years? I have thrown away breadboards because of this possible myth, since I've had stuff in them for 2 years or more. :) \$\endgroup\$ – Dave Jan 5 '11 at 16:01
  • \$\begingroup\$ Probably.... I can't remember exactly how long. \$\endgroup\$ – BG100 Jan 5 '11 at 16:03
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    \$\begingroup\$ @Dave And you didn't test to see if they are working!? \$\endgroup\$ – AndrejaKo Jan 5 '11 at 17:01
  • \$\begingroup\$ I used a breadboard two weeks ago that had components left in it since August (4 months). It wasn't anything super-sensitive to weak contacts, but it worked fine. \$\endgroup\$ – Kevin Vermeer Jan 5 '11 at 17:16
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Addressing the matter of "losing springiness", or more technically setting the springs by exceeding their yield strength, all that really matters is how much stress (pressure) you subject them to, which will depend on the strain (displacement). Over a very long time, they may take a set, but it would take years or extremely elevated temperatures.

Basically, avoid inserting extremely large component leads (diodes are the most common offender when breadboarding I think) into the holes. That's your enemy, not time.

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  • \$\begingroup\$ ah, yes, diodes are absolutely the worst. I had some stuck in the breadboards that I tossed out. :) \$\endgroup\$ – Dave Jan 5 '11 at 23:52
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    \$\begingroup\$ Some other candidates are power ICs, transistors, pots and switches. The latter two also cause stress when they're turned or pushed. I have a few boards where I've marked "dead" tracks that are probably caused by some of these.. \$\endgroup\$ – XTL Jan 11 '11 at 18:10
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I'm mostly using common sense here, but let's see what would happen to a board when it's left with components in.

Oxidation would occur even with no components. Probably some parts of the springs would oxidate differently without components than if components are in, but contact surfaces would probably be more exposed without components in, so I don't think that having components in would make more bigger impact then just having board sit in same conditions without any components.

Next, let's take a look at problems which could come from components themselves. Most components don't produce any debris by just lying around, so only problem could be bad electrolytic capacitors which could leak and contaminate the board. Maybe broken LCD could contaminate board too? I can't think of any other components which leak at the time.

If we take a look at the contacts themselves, cold welding could cause problems if the components need to be removed and board repurposed for another use. I don't think that cold welding would cause problems with signal quality on the parts which were left there and allowed to weld, because that's what we use for standard network cables and it works. If the components are removed, contact surface of the springs could be damaged or contaminated by remains of the weld. How big problems this is would depend on materials used for springs and component leads.

I really don't know what happens to springs which are left in a certain non-relaxed position for extended periods of time, but there could be problems with that. But then again, I think that springs would wear out more by inserting and removing components.

In the end, I don't think there would be any reason for anything bad to happen if prototypes do remain assembled on a breadboard.

Since the myth comes from a school, maybe the biggest issue would be simple mechanical damage and problematic storage of breadboards. As far as I see it, components are exposed on top of a breadboard and can be damaged very easily. Also, it would be difficult to stack populated breadboards. On the other hand, I don't see anything breadboard specific here. Same rules would apply to any other type of prototyping board.

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    \$\begingroup\$ I think your comment about oxidation occurring more readily without components really depends upon the metals in question. Back when I used to build PCs, they always said to avoid using gold-plated SIMMs in slots that are tin-plated. I imagine the same thing goes for breadboards. I assume they are tin-plated, so if you get a gold-plated SIP header and leave it in there, perhaps there is a risk there. \$\endgroup\$ – Dave Jan 5 '11 at 23:55
  • \$\begingroup\$ @Dave As far as I know, that's correct. I just thought that metals would already be picked in such way that their contact won't cause oxidation. \$\endgroup\$ – AndrejaKo Jan 5 '11 at 23:59
  • \$\begingroup\$ I had thought they were nickel-plated, or, IIRC, plated with something that is conductive even when oxidized, such as silver (there are no silver-plated contacts in breadboards as far as I know.) \$\endgroup\$ – dmoisan Jun 5 '11 at 20:03
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I would only worry about the "spring" if you are using over size leads. You could see a issue with oxidation. Usually removing and reinserting the wire or component will "wipe" the oxidation on the contacts.

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As I understand it, springs only wear out when they move. Leaving them loaded, or leaving them unloaded should be fine. What you'd want to avoid is unnecessarily unloading and reloading them.

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In a past life I breadboarded a 555 timer circuit together. The circuit did splice detection on a Asphalt roofing line. The area was subjected to high humidity. The circuit ran flawlessly for 10 years until they shut the plant down - otherwise it may still be running today.

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I have friends who have permanently-constructed projects using breadboards.

In this case, it was a audio crossover, and it had been assembed on a solderless breadboard, the wires were given some additional retension by being glopped down with hot-glue, and the whole thing was stuck in an enclosure, and then used for years without issue.

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