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I am trying to mitigate between costs, ease of mounting, of enclosure matching and costs for a smallish PCB (< 100 g / 4 oz and about 35 x 50 mm / 1.5 x 2 in) used inside a passenger car. And so far I have found these methods:

Snap-in universal anti vibration guides:

Snap-in universal anti vibration guide

Double sided adhesive tape:

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Adhesive standoffs:

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Vibration dampers:

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Spring washers:

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Staking and potting I think are a bit too much. Any experience with the above methods you could share ? As a side note, would it hurt not to use any anti-vibration mechanism at all in my scenario ? Largest component would be a button press switch.

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closed as too broad by Trevor_G, pipe, Enric Blanco, Voltage Spike, uint128_t May 14 '17 at 15:53

Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer. Avoid asking multiple distinct questions at once. See the How to Ask page for help clarifying this question. If this question can be reworded to fit the rules in the help center, please edit the question.

  • \$\begingroup\$ What is the mass of the most fragile part and whole assembly. Some parts are sensitive to high g short duration others (heavy) to low g, long duration. As such all HDD's used to have elastomer shock isolation have been eliminated in last 25 years due to reduced mass and risk of resonance as all elastomer isolators (that I have seen &/or tested) have a gain or Q>5 at resonance. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 9 '17 at 19:42
  • \$\begingroup\$ Have you done fragility boundary curves yet? g vs v vs t on shock tests! \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 9 '17 at 19:48
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The most common industry practise for fragile leaded components is to glob polyurethane adhesive to prevent motion. These come in many grades but sub-floor adhesive works great.!!

PSU makers use the clear , brown or white stuff for ferrite, caps and large relays, magnetic etc. sorry no vendor p/n on hand.

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  • \$\begingroup\$ PSU makers ? I'll grab a broken old PSU and check it out. Sub-floor adhesive, what's that in plain English ? And those comments - all Chinese to me :D. I am starting to think I can get away without any such protection. For sure most electronics inside the car are not protected, isn't that so ? \$\endgroup\$ – kellogs May 9 '17 at 23:54
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    \$\begingroup\$ It's comments like this that make some Chinese:) products garbage because they break so easy because some didn't learn the mechanical details of fragility like the TW or Japanese did. So look at how PS parts are globbed to become rigid. Even some Apple connector/cable designs are garbage and wearout easily. homedepot.com/p/… It does add capacitance, so use where needed to stiffen parts that can vibrate or even USB connectors that stress solder joints from yanked cables and allow few days to harden fully. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 10 '17 at 1:12
  • \$\begingroup\$ can't beat the cost of this solution \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 May 10 '17 at 1:20
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    \$\begingroup\$ polyurethane, silicone etc are thermal insulators, so that is not wise unless low power dissipation or with thermal conducting leads. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jan 12 '18 at 14:10
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    \$\begingroup\$ thermal resistance with convection air is somewhat like Ohms Law for current and voltage rise except Pd * Rja = Temp rise. Conformal Coating without airflow adds huge thermal resistance (low conductance) that must be considered for hotspots. \$\endgroup\$ – Tony Stewart Sunnyskyguy EE75 Jan 13 '18 at 1:33

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