Cannot stick resistors to breadboard

I have been tinkering every once in a while with my Arduino, learning slowly and bit by bit, but I am finding one thing that is really making it extremely difficult (the most difficult in fact) is getting resistors to stick to the breadboard. The connections are flimsy at best and will not go all the way in. I tried to experiment with making a photoresistor activated relay switch (using Robojax's video on YouTube as a guide) but I did not have the module he had, so I tried to use my breadboard to mount the sensors.

Only they never connected at all and just fell the moment anything was moved. I am not even sure if the resistors stuck.

Is this normal with solderless breadboards? Because this is actually my biggest issue with arduino projects at the moment. The dupont cables fit in snugly and perfectly, but the resistors just don't want to. What can I do to alleviate this issue?

Some resistors have different diameter leads. I purchase regular 1% metal film resistors. These leads hold fairly well in my solderless boards.

The solderless boards take a very narrow range of lead diameter, not every lead will fit or retain a reliable contact. If you have (for instance) a relay that doesn't fit well into the solderless breadboard holes, you will have to solder a dupont extension of the relay leads.

You will find that solderless boards don't deal with movement very well.

Makes for a different situation all together. But I think I can figure it out. Since the resistor and photosensor need to work in series I'll need to wrap one resistor end to the other.

Are you trying to put more than one lead into a hole in the breadboard? Is your breadboard new or old? Have you ever forced in leads that were too big for the breadboard to hold?
Paul

No. It is newish (I got it last Christmas, it was not used much). Yes I did try to force the resistor leads, but they didn't go all the way in, they just got bent.

I did make some LED projects with it, so I know that they work. But any movement to the breadboard would loosen them and make them fall off, which would make actually making a useful project quite limited.

I do have another question. when connecting the stuff on the breadboard to the arduino, the breadboard can have it's own power supply, correct? I have plenty of battery packs and batteries to use and I think that would make it easier since I won't need to use the arduino's power supply for the board.

For sure - that's what I use. They have pins on the underside that just clip directly onto standard breadboards - like this one:

Blockquote For sure - that's what I use. They have pins on the underside that just clip directly onto standard breadboards - like this one:

Oh my! I got one of those modules with the Arduino starter pack that I got! Time to put it to good use.

Absolutely!

I had a power brick with the right sized connector on the end (which probably just about qualifies as a miracle in it's own right) that I use to plug into it. Makes all the difference in the world when driving things like LED / LCD displays.

Just do not try and power it by the "barrel jack". The 5 V regulator on the board has no heatsink and cannot support more than a couple of hundred milliamps if that. A USB "phone charger" plugged into the USB connector (you will need an adapter) is more practical.

Approximately how far into the breadboard did they go before getting bent?

Blockquote Approximately how far into the breadboard did they go before getting bent?

I really don't know, unfortunately. It didn't seem to go that far since it just never got any more or less stable.

Blockquote Just do not try and power it by the "barrel jack". The 5 V regulator on the board has no heatsink and cannot support more than a couple of hundred milliamps if that. A USB "phone charger" plugged into the USB connector (you will need an adapter) is more practical.

Just my rotten luck then. The smallest battery pack I have is 3 AA batteries at 4.5 volts. If I need to get a phone battery pack I might as well get that.

Otherwise I can just plug in the batteries directly. Battery packs usually have their leads as fairly stiff hook-up leads to make them easier to put into terminals. I can also tie them to dupont cables and secure them with electric tape before plugging in the other end into the board. That'll work just as well.

It is expected and normal for further insertion of leads into a solderless breadboard to be blocked after approximately 6 mm (0.25") of insertion. It is sometimes possible to push thin leads farther in, but what is happening is it has bent and is now traveling laterally through the innards of the breadboard, which can cause shorts to random rails in addition to the one the pin was inserted to. So make sure to not do that. The standard ~6 mm insertion distance will provide adequate electrical and mechanical stability.

What I have experienced with some of my breadboards is that it can be very difficult to insert leads into the clips. When this happens, insertion stops just past the upper plastic case, about 2 mm of insertion distance. What is happening is that the lead is hitting and hanging on the edge of one side of the metal contact clips instead of being funneled between the two clips as usual. A little bit of wiggling around will get the lead on the right path and inserted as usual, but if you don't do that and leave it at the 2 mm insertion distance then you will have a very unreliable electrical and mechanical connection.

If you are getting the normal ~6 mm insertion distance, I will suggest that you cut the leads on the resistors down to that length. If you leave the leads at the factory length, then the leverage of the resistor hanging off the long leads will result in it being more likely to move around or perhaps even to come out with enough jostling. It also makes shorts much more likely.

Breadboards don't provide the most reliable of electrical or mechanical connections and I recommend using them only for prototyping circuits. However, I've never had any problems with resistors falling out of a breadboard.

Hi,
Can you please post a picture of your board and the resistors you are trying to plug into them?
Even a resistor "inserted" would help.

Thanks.. Tom... :smiley: :+1: :coffee: :australia:

I'd encourage you not to "sweat" using the barrel connector; it's there for a reason - it works - it just has limitations. Adjacent to my left elbow as I write this I've had a bright 8 digit 7 segment LED display running for over 3 hours & a Nano ... all powered from a 9V DC power source plugged into that jack. When I put a finger on the regulators I can't even feel any warmth above room temperature.

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Wow you have some very neat (precise) jumpers :slight_smile: Mine aren't nearly as straight.

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Hi,
@JohnRob
@anon12459472
OCD, symmetry and order. :laughing:

Tom... :smiley: :+1: :coffee: :australia:

@TomGeorge @JohnRob I've learned from experience that one needs to have all of one's ducks in precise rows before posting anything here or one gets called out for it ... :wink:

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I use longnose pliers. Place the resistor on the board till it does not go further, grab the lead one or two millimeters above the board with the pliers under 90 degrees to the lead and carefully wiggle the resistor lead down, grab again a little higher once the pliers are touching the board and push down. Repeat for the other leg.

Another thing that might help is to first insert the end of a dupont cable in the board where the resistor must go, remove it and insert the resistor (using above technique if needed).

4.5 V from three alkaline "AA" cells will run most things perfectly well. :+1:

Indeed. :grin:

And that is probably within the limits a 9V, given that you are in fact using a regulated 9 V supply.

So the display is apparently drawing something less than 200 mA if you are using full brightness - are you? A matrix fully lit at maximum brightness would draw 320 mA and directly proportional to the brightness setting.

So why do you have one pushbutton to ground with INPUT_PULLUP and another to Vcc with an external pull-down? :woozy_face:

Excellent points. :+1:

And I'm sure that if you tried to power an arc welder it would probably exceed the limits of the regulator as well. Thankfully MOST people don't need to run arc welders from barrel inputs ... or fully lit matrixes - which is why it works just fine for the vast majority of people - which is why warning people off them for no good reason does more harm than good.

As with most things in life one just has to make sensible power decisions with regards to the limitations of what's available; and most of the time that's probably a lot less than 200mA; it certainly has been for EVERY project I've ever completed.

Because that's what the person I was helping needed to generate a falling triggered ISR on the RELEASE of the button to start the chronograph - and I'd replicated it for testing. It's amazing the wrong conclusions you can reach when you try to score a point without knowing the full story isn't it ...