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I am struggling with the front panel setup. I need to align 3 types of components: push-buttons, potentimeters and 5mm leds. enter image description here The potentiometers have a nut to fasten it to the front-panel, for the leds I have small plastic mounting rings. The push buttons would need to go onto a pcb, that I could mount under the front-panel with stand-offs - the height looks good to me: enter image description here With this approach getting the leds mounted is complicated - not a lot of space and I would push the pins in millimeter perfect so that the led body would click into the panel mount rings.

I could also just mount potentiometers and leds into the front-panel and wire things freely, but then I have no idea how to handle the push buttons.

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    \$\begingroup\$ you have not asked a question .... put a small piece of the perf board under the pushbutton switch to raise it away from the main perf board \$\endgroup\$ – jsotola Jul 7 '18 at 19:31
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    \$\begingroup\$ This is where electronics designers get to realize that building the custom box is non trivial \$\endgroup\$ – Dirk Bruere Jul 7 '18 at 20:08
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    \$\begingroup\$ This is where a Process Engineer can make a trivial solution out of this with tool guides for installation. \$\endgroup\$ – Sunnyskyguy EE75 Jul 7 '18 at 20:36
  • \$\begingroup\$ I would have mounted button and LED topside and switch under board so top side protrusion is even. \$\endgroup\$ – Sunnyskyguy EE75 Jul 7 '18 at 21:38
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From your somewhat scrambled description you only have problems with LEDs... which is strange because the LEDs are the only components with long flexible leads that could be bent easily to required position.

So, bend the leads to get the LEDs as close to required position as possible but do not solder them. With everything else in place attach your perfboard to front panel, guiding LEDs into their holes. Then solder them, while holding steady in required position.

If you are OK with LEDs sticking out a bit, push them forward until the flange is flush with back of the front panel before soldering. This will ensure perfect alignment of them all.

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  • \$\begingroup\$ Good point. I'll probably do this. I'll carefully bend the legs and use the panel to guide the length, then solder them. Thanks! \$\endgroup\$ – ensonic Jul 7 '18 at 20:39
  • \$\begingroup\$ Another approach is to make a fixture to hold the LED at the correct height during soldering. That has the advantage that it can be done with a panel of boards before the test jig. \$\endgroup\$ – Spehro Pefhany Jul 7 '18 at 20:56
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Often a right angle installation is preferred for this sort of situation, but it seems like you are committed to a vertical one.

Often LEDs are placed on molded plastic standoffs which fit between the leads and help establish an appropriate, consistent height.

It it also possible to have a small locking bend put in the leads at a specific length by machine for consistency.

For the pushbotton you can buy key caps in various heights, have custom ones molded, or for a prototype make them with a 3d printer (just be careful that inter-layer roughness does not cause them to catch on the panel) or from plastic bar stock on a benchtop lathe.

Another option would be to switch to bulkhead mount components, and put wiring harness terminating in crimped connectors on them, plugging into headers on the board.

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One approach would be to mount the pot into a break-off section of your PCB, joined to the rest with a flat cable or wires. Then the nut mounts the pot to the panel and the pcb can be positioned to suit the switch.

For the LED, you can position it prior to soldering, or use an SMT LED and a plastic light pipe, which protects the LED pads from the user pushing on the LED.

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    \$\begingroup\$ Using a plastic light pipe is a nice idea, will do a bit of research how to terminate it on the front-panel \$\endgroup\$ – ensonic Jul 10 '18 at 17:53

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