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I want to use several of the 'filled PCBs' below, or other ones, but the question does not change. enter image description here

How can I fix such thing in a case, or on a proto/veroboard PCB (like the picture below)?

Protoboard

I thought about:

  • Glueing: but since the case (including the components) will be moved a lot, it doesn't seem a good way.
  • Using tie wraps, in this case it might work because it can be put around the yellow component, but what if I want to use another component that does not have a nice yellow box?
  • Using one of the above methods with spacers to prevent contacts with the protoboard.

I don't need a professional solution, but I want a solution that doesn't break or getting loose after being 100 times moved neither.

Update

I asked a similar earlier question. However, this was about a temporary solution, in which I expected components need to be changed/added. However, in this case it's about a fixed/known setup. So I hope that a more professional (or at least 'better') solutions exist.

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    \$\begingroup\$ I would suggest using a case with slots in it for a pcb, but it looks like that particular pcb is stuffed full right up to the edge so that might not work. \$\endgroup\$ – Hearth Apr 28 '18 at 13:55
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    \$\begingroup\$ by "will be moved a lot, " do you mean get's a lot of vibration? \$\endgroup\$ – Sunnyskyguy EE75 Apr 28 '18 at 13:57
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    \$\begingroup\$ For mounting to another PCB, use rigid pins for the input and output connections, and solder them to that PCB (unless you have extreme vibration tolerance requirements). Design that one with mounting holes, of course. \$\endgroup\$ – Brian Drummond Apr 28 '18 at 14:01
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    \$\begingroup\$ Re:gluing, does this mean you will be removing the electronics from the case? \$\endgroup\$ – loudnoises Apr 28 '18 at 14:15
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    \$\begingroup\$ @MichelKeijzers - Hi - To help avoid duplication of effort, can you edit the question to explain which parts of this question about fixing PCBs without mounting holes into a case, are different from your earlier question which seemed to be a very similar question: "How to 'fix' this in an enclosure without glueing?". If you can focus on the difference(s) with this new question, and explain why the answers to the earlier question aren't enough, I think it can only reduce the chances of this one being closed as a duplicate. Thanks! \$\endgroup\$ – SamGibson Apr 28 '18 at 15:09
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Use a box with card guides, (ie grooves in the walls) and fit a PCB card guide

Now the board / boards are horizontal and closing the lid locks everything in place.

Search for "P.C. Board Card Adaptors" or "Allows mounting of PC boards horzontally within the enclosure."

Hammond 1591Z6 (others manufacturers make similar products)

enter image description here

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  • \$\begingroup\$ Actually I really like this solution... even easy to make myself to accomodate different parts. \$\endgroup\$ – Michel Keijzers Apr 28 '18 at 20:27
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    \$\begingroup\$ This is a Hammond 1591Z6 \$\endgroup\$ – D Duck Apr 29 '18 at 13:47
  • \$\begingroup\$ Thanks, I really like this solution, although my enclosures are smaller, but I could easily make myself something similar (just carve out some lines from the wood). \$\endgroup\$ – Michel Keijzers Apr 29 '18 at 14:26
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An Adhesive that has high bond strength, yet not brittle made of Polyurethane is about the best. Some UV cured Silicones are often used in Industry.

I have found this Polyurethane to be an very economical (cheap in bulk) and very reliable adhesive to improving the vibration isolation of components and rigidity of a structure. It is not brittle and has exceptionally high adhesion qualities far better than hot glue which might be a quick fix as well. The down side it the cure time for the low VOC versions avail. now is 1 to 3 days till fully cured if there is exposure to air.

Test a couple of sticks at the same time and you will be surprised at the strength. I also use it for carpentry such as mounting drawer slides where screws are not possible.

Here is a commercial solution from Dymax to prevent broken solder joints. You do the same with the Polyurethane subfloor adhesive, and also use it to adhere the corners inside the container, although the dispenser is more bulky.

If you look in any PC power supply, you will get the idea for securing any parts that can move first. enter image description here

enter image description here

Apply to each moveable part with at least ~ 1 mm and the surface area determines the holding strength. Allow 1hr to get firm and 1 day to cure or so. Commercial solutions use accelerators.

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  • \$\begingroup\$ Thank you very much for this answer, and also the pictures. Glue seems not so professional (although I am myself a complete amateur), but I like to know how it 'should' be done. It seems glue is indeed not a bad solution at all. I'm not sure if I can get the exact glue you have, but Im sure I find something similar. \$\endgroup\$ – Michel Keijzers Apr 28 '18 at 20:24
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    \$\begingroup\$ I just came back from shopping and found what you might look at. gamma.nl/assortiment/rubson-constructie-schuim-750-ml/p/B446121 Polyurethane structural adhesive \$\endgroup\$ – Sunnyskyguy EE75 Apr 28 '18 at 21:29
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    \$\begingroup\$ No just North of Toronto which I think is in my profile \$\endgroup\$ – Sunnyskyguy EE75 Apr 29 '18 at 1:50
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    \$\begingroup\$ Here a tube of PU < $10 \$\endgroup\$ – Sunnyskyguy EE75 Apr 29 '18 at 11:52
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    \$\begingroup\$ I just looked around in your country , which why profiles are so useful \$\endgroup\$ – Sunnyskyguy EE75 Apr 29 '18 at 18:27
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It's a bit unclear, but I'll interpret your question as asking how to mount one of the boards in your top picture on one of the boards in the bottom picture. You say this will be "moved a lot", but it is unclear if you mean the individual sub-assemblies need to be movable within the larger device, or of the larger device will be subjected to vibration. I'll assume the latter.

It looks like the board modules have thru holes for the external connections. My first reaction is to use those holes to mount the module onto the prototype board. Line up the holes with where you want to connect on the bottom board, insert a wire thru both boards, and solder. To keep other parts of the top board from shorting to the bottom board in places other than the intended connections, use a insulating layer of cardboard or fairly rigid paper. In electronics assembly there is something referred to as fish paper that is used for that purpose. If you need additional mounting strength, use gobs of hot glue.

If you are just inter-connecting multiple modules without adding parts of your own, then connect them with wires and mount the board on something non-conducting with lots of hot glue.

Note that these modules are not designed for vibration. The two large electrolytic caps seem to be just hanging from their leads. That won't last long in a high vibration environment. You can make it more rugged by using hot glue or epoxy, but beware of adding too much thermal insulation in places that get hot.

Ultimately, these are not the components you should be using in a high-vibration environment.

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  • \$\begingroup\$ Thanks for your answer. And yes, I mean exactly what you describe (how to add the upper one, on the lower one, to add in a case). I meant the larger device. Inside everything is stable (unless the complete enclosed device is moved, which will). I will check the fish paper. Although I already ordered some time popsicle sticks (for ice creams) which I never used but probably have the same properties, although a bit thicker. \$\endgroup\$ – Michel Keijzers Apr 28 '18 at 20:32
  • \$\begingroup\$ About vibration: the entire device will be moved in a car, will be in a bag dragged around, and even the device might fall now and than from like half yard on the floor (hopefully not too often). It will not be in a continuously vibrating room, except maybe on a slightly vibrating floor (music stage). \$\endgroup\$ – Michel Keijzers Apr 28 '18 at 20:32
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I am assuming that's an AC-DC isolated power supply.

There should be at least 4 connection pads, two at the end shown (DC output) and two more at least at the other end (AC input). If those holes are ~1mm diameter you can mount the board on short pins inserted through the holes and soldered into your perf board. Either round pins (eg. see Mill-Max) or use the pins from some 0.1" pitch headers (0.025" square, so they are a bit loose in a 1mm hole). Cut them off in singles and use the plastic to space off and support the PCB from the bottom.

enter image description here

If you pick the right pins and sockets you can even make the boards plug in, however you'll have to find a way to retain the board.

Note: The holes that can be seen are filled with solder right now. If you have a decent desoldering tool, clearing them out is dead easy.


Below you can see a similar product (but safety agency approved and from a reputable supplier) that happens to be inside a plastic housing, but the mounting is accomplished via the pins (perhaps stabilized with a bit of adhesive on the bottom):

enter image description here

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  • \$\begingroup\$ Very nice solution, thanks. I have pin headers I could use, and also spacers. I have a 20 euro soldering device and solder wick, not a desoldering device (being an amateur). \$\endgroup\$ – Michel Keijzers Apr 28 '18 at 20:36
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3M VHB (Very High Bond) double sided acrylic foam tape onto the relatively flat bottom side of the PCB.

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  • \$\begingroup\$ The same stuff that is used to hold gopro mounts onto helmets? Brilliant idea - that stuff is hard to break off. Downside its also hard to get off surfaces, and could easily rip copper tracks off a board. Still OP didn't want it to move :) \$\endgroup\$ – Criggie Apr 28 '18 at 21:57
  • \$\begingroup\$ I use VHB for everything :) \$\endgroup\$ – bitsmack Apr 30 '18 at 2:45
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One could also solder stout wires to big and grounded solder joints or to the ground plane, then either make loops at the ends and screw down the loops, or just solder the other end to the carrier board (if mounting to a prototyping PCB) . NOT an acceptable technique, however, to mount a heavy and potentially mains connected (or able to touch anything mains connected should it come loose) module as shown in the first picture.

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  • \$\begingroup\$ Thanks... might work for other components, so it is a good solution in some cases (but maybe not this one). \$\endgroup\$ – Michel Keijzers Apr 28 '18 at 20:33

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