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After making a prototype circuit board, I usually glue four rubber pads/bumpers to the bottom, to keep it stable on my desk:

enter image description here

Unfortunately, my boards are usually too light. When connected to a few cables, they float around to wherever they're pulled by the cables. Add to that some oscilloscope probes, and I'm even more in trouble.
 

What I'm looking for
I'm looking for dead weight components that I can glue or solder to the bottom side of my circuit boards. Something I can buy in relatively large quantities (like a pack of 100) and low price.
 

Extra benefit
A nice extra benefit is the psychological aspect. A heavier product "feels" like it's better quality ^_^.
Nice comment from @JRE:
Some manufacturers agree with you about things needing a certain weightiness to feel right. The Motorola HMN1081 hand microphone (know colloquially as "the potato") had a block of metal screwed to the inside of the housing for just this reason. The housing is plastic, and the parts inside don't weigh much, so the Motorola engineers added a weight to make it "sit" properly in the hand. I looked, but couldn't find a service manual or parts list, but I've disassembled many Motorola radio microphones.

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    \$\begingroup\$ This conversation has been moved to chat. The purpose of comments is to request clarification or point out errors so that the question can be improved. They are not for extended discussion, nor are they the place to write answers. Note that this is really two independent questions: One about holding prototypes steady while working on them, and another about adding heft to finished products for a sense of "quality". \$\endgroup\$ – Dave Tweed Oct 30 '19 at 21:01

10 Answers 10

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Power your board from a 12V 7AH Sealed Lead Acid Battery. Then hot melt glue your board to the side of the battery.

enter image description here

Similar to the ideas shown by @DaveTweed I have mounted prototype parts to a piece of wood to facilitate ease of use on a desktop or workbench. The following example shows work being done to modify the firmware in an existing product that had no existing debug capabilities. I built a small interposer to replace the native MCU with an instruction set compatible MCU that had full on-chip debug features. I also built an easy to use replacement for the device front panel with LEDs and tact switches and mounted that on the same piece of wood.

enter image description here

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    \$\begingroup\$ Haha, good idea! \$\endgroup\$ – K.Mulier Oct 29 '19 at 12:59
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    \$\begingroup\$ +1 for the cheesy photoshop job alone. \$\endgroup\$ – Spehro Pefhany Oct 29 '19 at 13:03
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    \$\begingroup\$ @SpehroPefhany, could do with a lens flare. :) \$\endgroup\$ – user98663 Oct 29 '19 at 13:07
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    \$\begingroup\$ An alternate solution, especially for a device like a cell phone, is to glue it to a brick. You can probably find one for free in your neighbor's yard or at a local park. \$\endgroup\$ – Caleb Reister Oct 29 '19 at 23:01
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    \$\begingroup\$ @SpehroPefhany - Do you think I should have shown some of the hot melt glue oozing out along the edge of the board? \$\endgroup\$ – Michael Karas Oct 30 '19 at 7:44
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When prototyping, I often run into the same issue. What I usually do is find a sheet of suitable material that's larger than my board. It can be anything — wood, plexiglass, scrap PCB material, or even metal. I use the mounting holes in my PCB to locate and drill matching holes in the sheet, and then use nylon standoffs to fasten the two together — they're easy to tighten and loosen with fingers alone.

Then, I can set something heavy on the sheet to keep things from moving around (put your stick-on feet under the sheet), and I can also use the sheet to stabilize or provide strain relief for external connections to the board, or even to hold additional circuits that assist with the debug process.


Here's one example, showing a prototype DSP board on the right connected to an "I/O breakout" board on the left for testing:

DSP breakout

It's very easy to remove the upper set of standoffs without tools in order to get access as needed.


Here are a couple more from a very long time ago (mid-1990s — note the dust!), and I wasn't yet using the nylon standoffs. That's a trick I used on more recent projects.

This one, on plywood, is a simple audio function generator in the foreground, and a power supply in the background:

function generator

Second example, on PCB material, from left-to-right are a digital audio interface evaluation module, some custom "glue" logic, and a DSP evaluation module:

DSP prototype

Note that the PCB material can be used as a ground plane — see the wires on the far left and the far right and the shield connections on the BNC jacks.

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    \$\begingroup\$ Variation on a theme: a piece of pegboard gives you a matrix of pre-drilled holes to attach your standoffs to. No hole drilling required. \$\endgroup\$ – bta Oct 29 '19 at 23:07
  • \$\begingroup\$ my Pine64 SBC is screwed (un-ironically) into a chunk of 2x4 :) \$\endgroup\$ – Grady Player Oct 30 '19 at 22:51
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Get some large nuts or bolts from a hardware store and glue them in. Not my invention, these have been seen inside commercial products to make them appear more robust.

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    \$\begingroup\$ Or leave some holes in the board layout, and screw them in; no glue necessary. \$\endgroup\$ – Nate S. Oct 29 '19 at 20:20
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    \$\begingroup\$ What I've seen in mice is a little metal bar inside, usually 1x2cm. Some devices have some variation of this. \$\endgroup\$ – Ismael Miguel Oct 31 '19 at 3:15
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My approach to this has been to include a 2.54mm (0.10") pitch pin header with 4 pins along one side of the board for smaller boards, or one on each end for larger boards. The pin header has no electrical connections. It's just a row of holes with isolated pads.

When you build your board, solder a strip of pin header into the holes.

Then, glue, clamp, or tape a small breadboard to your work surface. This gives you a solid place to "plug in" your prototype board. The pin headers offer plenty of friction to hold small PCBs still, but are easy to plug/unplug. It's quicker than dealing with standoffs. And you can quickly desolder the pins and remove them once you don't want them. Once your board makes it to production, you can either just leave the holes vacant, or remove them from the design.

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Copper busbars. So weight, very dead!

Heavy nuts and/or bolts. Also a good way to fasten the board and attach heavy wires. Or small M3 nuts, a 60W soldering iron can handle them.

4mm banana jacks. Drill a hole, solder in a bare banana jack (or female banana plug insert). Makes a board stand (if used in all 4 corners) and a great groundplane connection at the same time.

Electrolytics. You can always use extra power filtering, and a big lythic in each corner also makes a board stand.

Angle irons. Might even be solderable, otherwise bolt them on.

Magnets, how do they work? Probably need glue. Or just a counter-magnet/iron counterpart (nuts, again) on the other side. Great fastening method, if it doesn't interfere with magnetically sensitive components (cored inductors, electromechanical components, hall sensors).

Hint: With all hardware, avoid stainless steel, chrome plated and nickel plated types if you want to solder them down - these are far too finicky to solder to make a quick solution.

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    \$\begingroup\$ i1.wp.com/lowkeytech.com/wp-content/uploads/2015/04/… \$\endgroup\$ – D Duck Oct 30 '19 at 0:09
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    \$\begingroup\$ Expensive. A friend once built a PC for his boss, who went berserk at him for building him such a bad low spec machine when he was the boss and he deserved the best. So my friend gaffer taped a brick inside the case and told him they decked it out in the latest tech. The guy was chuffed to bits because it was heavy. Bricks and rocks are cheap. \$\endgroup\$ – NibblyPig Oct 30 '19 at 15:21
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I've seen zinc plates used. Zinc is heavier than you might think. In fact, the Heathkit MicroMatic Keyer used zinc to make it heavy.

Steel plates or angles will work too.

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    \$\begingroup\$ This. Zinc is just a little lighter than steel but much easier to form and machine. Last time I checked, it was also less expensive than steel. It is easy enough to buy as a bar or ingot but I have not seen it marketed specifically as an added weight. \$\endgroup\$ – Chris K8NVH Oct 30 '19 at 15:46
  • \$\begingroup\$ If you attempt to solder to zinc or pot metal or zamak, be aware that zinc metal fumes can make you sick! \$\endgroup\$ – rackandboneman Oct 30 '19 at 23:56
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Back when I worked as a hardware systems engineer, we used to always have blu tack around for sound/vibration dampening testing. We found it did a great job at holding cables and small boards around. 7 years later, I still use it as an embedded guy for my tiny kinetis FRDM boards (which weigh next to nothing).

You still use the rubber feet on the boards, but you hold down the cables with tacky, so nothing goes flying. It's clean, basic, reusable, fast and cheap.

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  • \$\begingroup\$ Very good idea! \$\endgroup\$ – K.Mulier Oct 31 '19 at 22:56
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Use LEGOs.

No, seriously.

I've been fiddling with LEGOs to develop my protos since I saw an awesome post by Anemia iDX on their blog.

I really liked their idea to use LEGO pieces to enable quick assembling/disassembling of components. It works like a charm to make your design easier to fiddle with and swap parts around.

enter image description here

But LEGOs aren't heavy!

Yup. That's true. However, while LEGOSs themselves aren't that heavy, you can grab a set of those things to put some extra weight on your project. Those pieces have a metal core, which makes them rather heavy - 50g a pop. Slap some of them beneath your frankenstein LEGO/Circuit board and it will get nice and heavy.

All of this seems like too much work. Why I should do this?

Honestly? I have no idea. Personally, I love the look of LEGO+Circuitry and the logistics of detaching/attaching modified circuit bricks. Playing with LEGOs is always delightful, and if I get to do so while trying to figure out how to implement a prototype for something that I might personally not like that much, all the better.

More so, if you have kids, you can bring them along for a very entertaining ride - LEGO is already fun, but when you're able to make stuff that actually works and do stuff for real, like a radio, a TV remote or a 1W Laser Cannon, you can have an incredibly satisfying bonding experience.

...Just be sure to avoid your significant other's stuff when playing with the Laser thing. That's not a mistake you'll want to make. I learnt that the hard way.

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    \$\begingroup\$ Waw, just waw! This is seriously over the top, but very inventive (and fun). +1 :-) \$\endgroup\$ – K.Mulier Oct 31 '19 at 12:52
  • \$\begingroup\$ I wish I could move your answer to bricks.stackexchange.com but the question wouldn't fit. \$\endgroup\$ – chicks Oct 31 '19 at 17:19
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I have seen manufacturers put lead weight inside premium products for this high-quality feel, so you are not alone in this observation!

I was going to suggest power transformers, and then I remembered what a pain it is to pass any kind of vibration testing with a heavy power transformer on board. (plus they are expensive if you want to purchase something by the 100).

Honestly, can you tie or clamp each board to something heavier? Like this: https://mk0isipkgnqjxo485w1r.kinstacdn.com/wp-content/uploads/2017/07/Test-Socket-Dual-Head.jpg

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Back in the old days, we used actual breadboards for this. These were heavy wooden cutting boards, usually stolen from Mom. This is in fact, where the term "breadboard" comes from, as a place to put electronic projects.

https://en.wikipedia.org/wiki/Breadboard

Today, I use clipboards for this purpose, and this provides most of what you're looking for. It keeps the project together and gives it some weight. Clipboards are also great for storing projects out of the way when working on something else.

enter image description here

You can use many different methods to fix items to the clipboard. Sometimes I use the clip itself, sometimes I use packing tape, sometimes double-sided tape, etc. Dry-erase clipboards like in the photo are very handy for making notes, but they are a little more expensive.

https://youtu.be/grLyHi-wfoo - see this technique "in action"

I like this technique so much, I named my Youtube series after it!

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    \$\begingroup\$ Good idea @Jasmine! \$\endgroup\$ – K.Mulier Nov 1 '19 at 21:41

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