Breadboard - Full Metal Jacket - Page 1
Forum section: electronics / general

author: PerranOak
author_rank: Frequent Contributor
timestamp: July 26, 2020, 12:44:24 pm
content: I've just bought a couple of BusBoard Prototype Systems BB830 breadboards.They came with thin metal sheets that the BBs can be attached to.Why is this? Is it to do with EM shielding? Should I attach them?Cheers.

author: ceoxrad
author_rank: Regular Contributor
timestamp: July 26, 2020, 12:56:11 pm
content: I think the idea is more to have a sturdy support to work on while using the breadboard,usually on those plates there are some posts to attach banana leads to route power-signals in and out.Most breadboards have double sided tape on the back, and tiny latches on the sides to join together more boards

author: rdl
author_rank: Super Contributor
timestamp: July 26, 2020, 03:51:03 pm
content: Sounds like the type that is same size as the board and not much more than heavy foil. It's to provide a bit of ground plane/shielding and using it is optional. In most cases I'd be surprised if it made any difference.

author: tooki
author_rank: Super Contributor
timestamp: July 28, 2020, 09:47:09 am
content: Quote from: PerranOak on July 26, 2020, 12:44:24 pmActually it’s for mechanical support. The contacts in a breadboard are held in only by friction and the thin tape on the back. Especially with high quality breadboards, which tend to have quite stiff contacts, inserting a component can start to push the contact strip right out the back, especially when the breadboard is new, with thick component leads, and/or when simultaneously inserting multiple pins into the same contact strip. The thin metal plate is for when you don’t mount the breadboard to an enclosure, backplate (like in the image attached), or similar.

author: PerranOak
author_rank: Frequent Contributor
timestamp: July 28, 2020, 04:48:25 pm
content: Ah.I will not use them then. It might be possible that if ham-fistedly pushed components in they may short between rows via this "foil".

author: rdl
author_rank: Super Contributor
timestamp: July 28, 2020, 07:28:27 pm
content: Quote from: PerranOak on July 28, 2020, 04:48:25 pmThis isn't likely due to the way the contact strips are made.Quote from: tooki on July 28, 2020, 09:47:09 amI'm pretty sure it's just a thin piece of sheet metal, same size as the board and not a heavy, painted mounting plate like the 3M type. There's no way to be certain without a photo though.

author: tooki
author_rank: Super Contributor
timestamp: July 28, 2020, 07:30:07 pm
content: Quote from: PerranOak on July 28, 2020, 04:48:25 pmNonsense. The point is to stabilize it so the contacts can’t slip out. As long as they’re in place, a short won’t happen. Do you really think an established manufacturer would ship out parts that cause shorts?The tape (which is actually often thin but very stretchy double sided foam) isn’t going to be perforated by the contacts, it’s tough and stretchy enough.I mean, just how thin is the metal sheet they included? Is it closer to sheet metal or to aluminum foil from the kitchen?

author: tooki
author_rank: Super Contributor
timestamp: July 28, 2020, 07:31:57 pm
content: Quote from: rdl on July 28, 2020, 07:28:27 pmI never claimed or insinuated that it was anything like the backplate of the 3M type. I said the thin metal plate is for when you’renotattaching to a heavy backplate.

author: rdl
author_rank: Super Contributor
timestamp: July 28, 2020, 07:58:49 pm
content: I didn't intend to make it sound as if you did.I've bought boards like this in the past. The metal is very thin and adds almost nothing in the way of strength or stability. The main purpose is apparently to serve as a rudimentary ground plane.PerranOak, look at about the 4 minute point to see how the contact strips are made. They are solid along the bottom, so it would be difficult to push anything through. Maybe with a nail and hammer...

author: PerranOak
author_rank: Frequent Contributor
timestamp: July 29, 2020, 04:35:25 pm
content: That's great, thanks all.The metal is about as thick at the aluminium cartons food comes in but is springy and nicely brushed.

author: tooki
author_rank: Super Contributor
timestamp: July 29, 2020, 08:49:41 pm
content: Thanks for the update. I vaguely remember one of my no-name breadboards having come with something like that. On a no-name breadboard, it’d probably not be worth the effort.But it looks like what you’ve ordered is a quality breadboard, and if it’s anything like my 3M breadboards, you’ll want to use the sheet! I just checked those, and on the one without a metal baseplate, if you turn it over, the foam backing is all wavy and uneven, higher where components were inserted, because the contact force is high enough to push the contact strip out a bit. It’s not going to fall out or poke through, but it’s certainly wasted energy when using it, not to mention necessitating slightly longer component leads. They readily push back in. I compared with one with a baseplate, unscrewing the board from the plate. Absolutely no movement of those contacts.