How Can I Make NICE Front Panel Push-Button Actuators for PCB SMD MC Switches? - Page 1
Forum section: electronics / projects

author: SuzyC
author_rank: Frequent Contributor
timestamp: January 05, 2016, 02:58:13 am
content: I made a really nice device that doesn't look or feel good to operate in a small black Bakelite project box (2-in by 4-in by approx 2-in deep box). I mounted several through-hole tiny push-button switches on a PCB mounted on one (2-in) exterior side of the box and they work fine, but the tiny round actuating buttons that the switches present to the user are not nice to look at, nor nice to touch and press, and the naked PCB sitting on the front panel looks so nerdy prototypical!Tiny push-button SMD or through-hole M.C. push switches are cheap and tactile and rugged and easily mounted on a PCB. The problem is to make a long button that extends from the tiny round actuating area of the switch on a PCB that goes through the side of a small ~3/16 to 3/8-in thick wall of the box to then have a good looking, small but larger, tactile push-buttonbuttonson what is then a front panel. One that give smooth operation, doesn't easily pull off. The device uses five switches to operate.Front-Panel screw and nut mount switches as an alternative would be just fine, much more expensive, take a lot of screwing around to mount them, and they would work except that they are much too big and use too much of the precious interior project box space and also too much front-panel space!Does anyone have any idea how to make a front panel actuator like this?

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 05, 2016, 03:23:56 am
content: There are small tactile pushbutton switches with longer shafts.Example:https://www.sparkfun.com/products/8605There are also key caps which push on to the shaft.https://www.google.com/search?q=tactile+switch+key+cap&source=lnms&tbm=isch

author: SuzyC
author_rank: Frequent Contributor
timestamp: January 05, 2016, 03:33:55 am
content: Thanks Richard Crowley!The problem with these switches you've linked is that they either have longer, but tiny round shafts or else are nice little buttons that mount directly onto the switches on a PCB with a low profile(this requires a PCB on the exterior panel), or that they have nice buttons shapes that are not removable and so cannot be removed to be then attached to the button switch on a PCB by being pushed into holes on the exposed(panel) side of a project box (These would require large holes to be drilled into the side panel to allow the large buttons to protrude.)The idea is to make my projects that not only work nice, but look nice, to conceal the private parts of the magical works hidden within, while not using up a lotta space within the box.

author: tautech
author_rank: Super Contributor
timestamp: January 05, 2016, 03:50:35 am
content: I've always liked the idea of loose "top hat" style buttons setup to be snug against tactile switches and the "brim" prevents them from escaping from the case. They wouldn't be hard to spin up from coloured plastic/nylon rod with a hobby lathe. Your choice to use very short tactile switches hard against the button or long units and the buttons drilled for the push rod.This means a fairly precise PCB mounting to make it all work.

author: SuzyC
author_rank: Frequent Contributor
timestamp: January 05, 2016, 03:57:40 am
content: That 's the ticket tautech! Can you tell me where you found a source for your affordable hobby lathe and plastic/metal stock?So far the best solution I have come up with is to superglue tiny but thick square hard rubber pieces onto the top of the round PCB switch buttons, then I tried pressing gold-colored metal thumbtacks having a long shaft through ~1mm holes in the panel to stick into the rubber pieces. Problem is, they are difficult to center onto the rubber on the switches and I have found that they are way too easy to pull off and be lost.I can easily visualize a brass round button that would have a shaft that pushed through the panel and secured by an interior c-clip on the shaft and then to be just the right length to to reach the top of the button switch and then the button bottom itself would bottom-out onto the panel to prevent over-travel so as to not damage the switch.I have taken apart the front panels of printers and VCR's and notice that the switches have a sheet of custom shaped cantilevered actuators that are cut onto a single sheet of flexible plastic. Don't try to make this at home!All I need to do is try to fine a source of metal stock and a lathe! Sounds to me though like a lot of work!Maybe a 3-D printer is what I have to save up for!

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 05, 2016, 04:15:56 am
content: Quote from: tautech on January 05, 2016, 03:50:35 amYeah, if only there were a reasonable source for them. I came to the same conclusion that the only solution was to DIY which isn't really practical for small-medium production run. But good enough for one-off hobby projects.

author: tautech
author_rank: Super Contributor
timestamp: January 05, 2016, 04:19:36 am
content: Quote from: SuzyC on January 05, 2016, 03:57:40 amHaha, thumbtacks (drawing pins we call them) is a good idea.SuggestionsSeparate PCB with only the controls, connected with ribbon cable/headers/whateveranddrill the tactile switch push rod with your PCB drill so the the point is either a push fit or glued in.Or if needed longer or larger diameter rod switches to allow deeper engagement of the pin.Just checked my selection, 3.2 or 6.5mm diameter rods but they're mostly TH snap in types.Quote from: Richard Crowley on January 05, 2016, 04:15:56 amQuite so Richard.But they will be available somewhere.I'll have a hunt on Aliexpress

author: ajb
author_rank: Super Contributor
timestamp: January 05, 2016, 04:23:21 am
content: Slightly more fiddly, but you could cut small bits of plastic into the shape of the button you want, then glue onto a slightly larger piece of plastic to create the tophat shape. Some hobby shops have a reasonable selection of plastic shapes, usually in white styrene, or you could do acrylic as well. A little solvent glue will hold the pieces together permanently. With care, and a sufficiently thin backing sheet, you could even have multiple buttons glued to one backing sheet (Ideally you could use the front panel as a jig to hold the button faces in position while gluing, just be careful not to glue the buttons to the panel!).If you've got access to a laser cutter, or are willing to use one of the laser cutting services, you could make arbitrary button shapes, and even engrave them with legends without too much fuss.

author: tautech
author_rank: Super Contributor
timestamp: January 05, 2016, 04:30:03 am
content: There's heaps on Aliexpress.Include "cap" in searches.http://www.aliexpress.com/item/20PCS-Tactile-Push-Button-Switch-Momentary-12-12-7-3MM-Micro-switch-button-20PCS-10pcs/32321453548.html?spm=2114.01020208.3.205.ORH1cS&ws_ab_test=searchweb201556_1,searchweb201644_3_10001_10002_10005_10006_10003_10004_62,searchweb201560_8,searchweb1451318400_6148http://www.aliexpress.com/item/100sets-Tactile-Push-Button-Switch-button-Cap-A14-12-12-7-3MM-Micro-tact-switch-seven/1261511250.html?spm=2114.01020208.3.279.9ELrR2&ws_ab_test=searchweb201556_1,searchweb201644_3_10001_10002_10005_10006_10003_10004_62,searchweb201560_8,searchweb1451318400_6148http://www.aliexpress.com/item/100pcs-7-color-A04-Tactile-Push-Button-Switch-Cap-tact-micro-switch-button-Cap-fit-7/32285421383.html?spm=2114.01020208.3.324.9ELrR2&ws_ab_test=searchweb201556_1,searchweb201644_3_10001_10002_10005_10006_10003_10004_62,searchweb201560_8,searchweb1451318400_6148

author: kuromaku
author_rank: Newbie
timestamp: January 05, 2016, 04:31:12 am
content: Quote from: SuzyC on January 05, 2016, 02:58:13 amSuperglue cap of your choice with extension to the switch? That's what I do for a (low volume) product of mine.

author: SuzyC
author_rank: Frequent Contributor
timestamp: January 05, 2016, 04:38:13 am
content: Thanks kuromaku,Sound like a workable idea, but I don't quite understand how to make and securely attach an extension!

author: tautech
author_rank: Super Contributor
timestamp: January 05, 2016, 04:39:33 am
content: Another:http://www.aliexpress.com/store/group/Switch-Cap/1575003_260803902.html

author: SuzyC
author_rank: Frequent Contributor
timestamp: January 05, 2016, 04:56:22 am
content: Thanks tautech, but I can't seem to understand why these buttons have square holes to attach to the round buttons on the PCB.Some of the keyboard type switches look very nice but I can't seem to find a source for square hole drills on the front panel.

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 05, 2016, 05:11:46 am
content: There are several ways of making square or rectangular holes/slots in panels.It is even easier in plastic panels where you can use a hobby knife or even hot knife in a soldering iron, etc.I just re-watched EEVblog #644 – How To Design Front Panels On Extruded Enclosures. Clever and elegant.http://www.eevblog.com/2014/07/24/eevblog-644-how-to-design-front-panels-on-extruded-enclosures-%C2%B5supply-part-14/

author: sleemanj
author_rank: Super Contributor
timestamp: January 05, 2016, 05:34:59 am
content: Something like this?Standard 6mm pitch switch, with a capCap OD 8mm diameter approx, ID of mating piece 3mm approx, OD of mating piece 5mm approx.The switches I've put these on are approx 9mm tall bottom of base to top of button without cap, but some other heights of switch have similar diameters at the top of the shaft which will fit this type of cap.

author: Jeroen3
author_rank: Super Contributor
timestamp: January 05, 2016, 08:33:14 am
content: You use above referenced tactile buttons and a secondary PCB layer elevated on headers or standoffs that features holes for the buttons and texts and such. Might even keep a cutout for an LCD.Like this concept:

author: FreddyVictor
author_rank: Regular Contributor
timestamp: January 05, 2016, 11:06:29 am
content: as already suggested by others, my solution was to use 1/4" acrylic rod pushed onto the tapering long shaft ofthese typeof buttonsthe rods can be any length you want & the results are quitereasonable

author: pmbrunelle
author_rank: Regular Contributor
timestamp: January 05, 2016, 01:51:08 pm
content: Thru-hole momentary toggles eliminate the need for a button. Also available in SPDT which makes debouncing dirt-simple.

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 05, 2016, 02:53:50 pm
content: Quote from: FreddyVictor on January 05, 2016, 11:06:29 amI did something very similar using acrylic cubes rather than lengths of rod.http://www.tapplastics.com/product/plastics/plastic_rods_tubes_shapes/cast_acrylic_cubes/136http://www.skylineplasticworks.com/Cubes.html

author: tggzzz
author_rank: Super Contributor
timestamp: January 05, 2016, 03:04:41 pm
content: Quote from: SuzyC on January 05, 2016, 03:57:40 amTry asking a local hackspace/makerspace or model engineerign society. Or google it.QuoteWith home 3D printers you will spend all your time fettling with it, only have a very limited range of materials, and the finish probably won't be good enough.I suggest you use a 3D printing house; Shapeways does many materials (metals, ceramics, plastics...) in different colours. DirtyPCBs does remarkably cheap white SLA prints.If you want a legend or ideogram in the button, then put the negative of it in the design, and finally fill it with paint yourself

author: Richard Crowley
author_rank: Super Contributor
timestamp: January 05, 2016, 03:21:38 pm
content: Quote from: tggzzz on January 05, 2016, 03:04:41 pmTry completing your user profile to at least reveal your location.For practical matters, sourcing materials and services varies dramatically depending on where you are.

author: RinkerLand
author_rank: Newbie
timestamp: March 13, 2019, 02:54:59 pm
content: I realize this post is old, but I just ran into the same problem. I like a lot of the suggestions here, but wanted to add one. make a "model" or "pattern" button. Then use that to make a mold and you cast cast as many as you want using resin or any cast-able material. also, I would be interested in seeing and hearing about the solution that you went with.I am actually going to have a custom, injection molded rubber "button set" where the "brims" of the top hats all join together to make it a single piece for easy insertion of all buttons at once. The challenge will be selecting the right rubber that is hard enough, but not so hard as to make a single button press actuate more than the intended button.here is a draft of the piece i will be using.