PCB front panel from other PCB - Page 1
Forum section: electronics / general

author: UHF
author_rank: Contributor
timestamp: February 03, 2020, 07:23:31 am
content: Hello, I'm new to PCB design and KiCad. I have a PCB with components and controls (lots of pots and a small display) and I want to make another PCB front panel to go on top. The idea is to get them from someone like JLC, with some of the SMD components fitted. My question is - how can I create the PCB front panel with the cut-outs in the correct place from the component PCB underneath? Is there a workflow in KiCad or some other way that would ensure alignment without hassle when changes are made. I use Fusion 360 as a hobbyist and was eyeing Eagle and it's integration, but I've got a KiCad design currently.Many thanks.

author: Rerouter
author_rank: Super Contributor
timestamp: February 03, 2020, 07:30:15 am
content: My method was to save-as the orignal PCB, use that to mark up the correct cutouts etc on a drawing layer, start deleting all the components and traces once doneThen exported the front panel as a VRML, and added that to the first project as a 3D model for a random part, so every time I updated and re-exported, it updated on the original project 3D viewer,As I don't use other 3D tools, it was a quick way to make sure everything lined up.

author: aix
author_rank: Regular Contributor
timestamp: February 03, 2020, 07:56:33 am
content: I use a combination of:sketching board outlines in Fusion and exporting them into KiCad (note that it's very easy to export your component board from KiCad into Fusion to use as a starting point);use "Append Board" feature in KiCad to append the component board to the front panel board, and then delete/clean up what I don't want.

author: UHF
author_rank: Contributor
timestamp: February 03, 2020, 08:52:48 am
content: Thanks for the suggestions, I'll have a play and see what feels right.

author: thinkfat
author_rank: Unknown
timestamp: February 03, 2020, 10:38:37 am
content: Mark the board outline and the component locations on the Dwgs.User layer of your PCB project.Plot this layer to a DXF file. Import the DXF file in your PCB front panel project. Use this as the reference for the panel outline and breakouts for controls.

author: UHF
author_rank: Contributor
timestamp: February 03, 2020, 01:45:20 pm
content: Oh I didn't realise you could produce more than just Gerber files using Plot. Thanks that's useful.

author: casinada
author_rank: Frequent Contributor
timestamp: February 12, 2020, 07:22:24 am
content: They just added Eagle into Fusion 360. It seems to be free for personal use.

author: VEGETA
author_rank: Super Contributor
timestamp: February 15, 2020, 11:01:43 am
content: I wanted to ask a similar thing. How do people stack or fix the front panel PCB to the actual front panel (assuming it is drilled and cut to fit the components)?

author: thinkfat
author_rank: Unknown
timestamp: February 15, 2020, 12:02:03 pm
content: Quote from: VEGETA on February 15, 2020, 11:01:43 amNuts and bolts?

author: VEGETA
author_rank: Super Contributor
timestamp: February 15, 2020, 12:02:55 pm
content: Quote from: thinkfat on February 15, 2020, 12:02:03 pmbut how to fix those from only one side without showing on the outside?

author: thinkfat
author_rank: Unknown
timestamp: February 15, 2020, 01:07:43 pm
content: Quote from: VEGETA on February 15, 2020, 12:02:55 pmDepends on how important the esthetics is for you. I myself I'm fine with nuts and bolts.PS: SMT pin headers and sockets, if you don't want drill holes to show up on the front.

author: VEGETA
author_rank: Super Contributor
timestamp: February 15, 2020, 01:29:24 pm
content: Yes sometimes bolts are ok to show outside but what if it is not ok?if smd headers to be used, then i guess one needs to do measurements very very precisely.do you have a video or photos for such a thing? like dismantling a front panel like that

author: donotdespisethesnake
author_rank: Super Contributor
timestamp: February 15, 2020, 07:56:51 pm
content: Quote from: VEGETA on February 15, 2020, 12:02:55 pmI haven't found a way to do that. I did think about using solder turrets with a thread, but that relies on a solder connection for strength which seems like a bad idea.The alternative is to use an enclosure which mounts the PCB behind the front panel, although that has other disadvantages.An example is the Platino platform created by Elektor:

author: UHF
author_rank: Contributor
timestamp: February 20, 2020, 06:13:33 am
content: Quote from: VEGETA on February 15, 2020, 12:02:55 pmSuperglue flat head screws or nuts to the inside of the front panel and bolt from the inside, could be a DIY solution.

author: VEGETA
author_rank: Super Contributor
timestamp: February 20, 2020, 07:11:37 am
content: Quote from: UHF on February 20, 2020, 06:13:33 amMy first guess was hot glue gun. However, I am interested in how it is done in commercial products without screws.

author: thinkfat
author_rank: Unknown
timestamp: February 20, 2020, 10:31:45 am
content: Quote from: VEGETA on February 15, 2020, 01:29:24 pmUnfortunately not, as I said I'm a nuts'n'bolts guy, but typically, you can export the positions of the pin headers from your PCB CAD program and then use that as a template for the front panel. WIth KiCAD, I usually go as far as creating a technical drawing of e.g. the front panel or other mounting elements, say, a heatsink or fixture plate on the Dwgs.User layer and then I plot this layer into a DXF and re-import it into the front panel PCB project, or I print it to have a drawing with measurements when going to the drill press for drilling and tapping fixture holes into a heatsink or a metal case. Of course you can use a mechanical CAD program for that as well. It all depends on where your constraints are.

author: VEGETA
author_rank: Super Contributor
timestamp: February 20, 2020, 10:44:34 am
content: My problem is not how to mount it and what measurements to use, but rather the method.I mean, how to mount the PCB on the front panel assuming there are no bolts or screws shown on the outside?

author: donotdespisethesnake
author_rank: Super Contributor
timestamp: February 20, 2020, 02:20:23 pm
content: Quote from: VEGETA on February 20, 2020, 10:44:34 amI have never seen a commercial product that does that, so I think there is no method robust enough for commercial application. If you can find an example, I would attempt a tear-downIf you have a metal enclosure, you can embed threaded inserts ("self clinching threaded standoff") into them so that they are flush on the outside, the outside could be painted. In our products we use a flexi membrane which has some buttons and LEDs embedded, which is simply glued on to the metal outer.

author: wraper
author_rank: Unknown
timestamp: February 20, 2020, 02:37:10 pm
content: Quote from: donotdespisethesnake on February 20, 2020, 02:20:23 pmScrews on front panel are not something unheard of. And it can look pretty good if done right. You can buy low profile or countersunk screws intentionally made to be not noticeable like these:https://www.tme.eu/html/EN/ball-screws-hexagon-socket/ramka_4296_EN_pelny.htmlhttps://www.tme.eu/en/details/b2.5x8_bn20/bolts/bossard/1480286/

author: wraper
author_rank: Unknown
timestamp: February 20, 2020, 02:43:24 pm
content: If you really need them hidden, then you can place adhesive decorative sheet on top of front panel. All screws will remain beneath it. That elector soldering station probably does exactly that. At least there certainly is decorative sheet with transparent window placed on top of panel.

author: VEGETA
author_rank: Super Contributor
timestamp: February 20, 2020, 02:46:03 pm
content: I had a crazy idea about making a solder joint then solder a nut on it. Then connect the PCB board to it via short length screw... but this seems hard.Look at these examples, no apparent screws:https://www.electronics-lab.com/wp-content/uploads/2017/06/Keysight-E36300-series-triple-output-dc-power-supplies_1800x1098_1497650062-1024x625.jpghttps://uk.rs-online.com/web/p/bench-power-supplies/8903853/The point is, injection molding is very expensive for low volume products... so I cannot design my own enclosure and put the screws in the bottom. Most available enclosures from Aliexpress and others have visible screws especially in front.Notice that I will most likely use a PCB front panel too

author: Rerouter
author_rank: Super Contributor
timestamp: February 20, 2020, 03:33:09 pm
content: Have used the nut idea in the past with success, you just need to recess it in the PCB. So the PCB takes the rotational and stress loads, not so much the solder,The tighter the fit the better, so work off whatever the manufacturer uses for there routing diameter to keep the gap as small as possible.And would recommend adding a lot of vias to the gold areas to prevent any pads lifting if your gap is larger than you thought.

author: poeschlr
author_rank: Regular Contributor
timestamp: February 20, 2020, 04:50:28 pm
content: Instead of using a nut there is always the option to use something likehttps://www.we-online.com/catalog/en/em/assembly/smd_spacer/(There are footprints and 3d models for these in the official KiCad library, they have however been added after the latest release so you would need to download the latest library snapshots to get them.)

author: jfiresto
author_rank: Frequent Contributor
timestamp: February 20, 2020, 08:03:31 pm
content: Quote from: VEGETA on February 20, 2020, 10:44:34 amFor making at most just a few, I have used MMA adhesive to bond threaded spacers to the back of the panel. I temporarily attach the spacers to the PCB with countersunk screws, to center them within the loose fit mounting holes. I then use the circuit board as a fixture, place and bond the spacers to the back of the panel, and finally swap in the final mounting screws after it has cured. MMA adhesive is not quite as strong as epoxy, but requires little to no surface prep and is much easier to rework.

author: donotdespisethesnake
author_rank: Super Contributor
timestamp: February 20, 2020, 09:22:28 pm
content: Quote from: wraper on February 20, 2020, 02:43:24 pmNo it doesn't., and no there isn't. You obviously have no clue what you are talking about.

author: wraper
author_rank: Unknown
timestamp: February 20, 2020, 09:41:22 pm
content: Quote from: donotdespisethesnake on February 20, 2020, 09:22:28 pmOf course I did not take this particular device apart to see if there are screws underneath but your comment is completely stupid and uninformed. I've seen plenty of enclosures to know there is decorative film with transparent display window over thicker plastic or metal panel. You can actually design and order one.https://www.alibaba.com/product-detail/JingYiDa-Manufacture-Cheap-Price-Customized-Self_60800087928.html?spm=a2700.7724857.normalList.56.3b85e64f4SwrRsOr at least it seems to be the cass since this appears to be rendering, not real device. And the other choice they had is to not bother with window and simply make uncovered opening.EDIT: seems this case never existed to begin with and is only a crappy rendering. They have even more convincing rendering of PSU: