STEP- and Gerber- File viewers ? - Page 1
Forum section: electronics / general

author: Uky
author_rank: Regular Contributor
timestamp: March 02, 2024, 03:53:22 pm
content: Q1==I have been trying to find a small free-of-charge STEP-file viewer that does NOT require creating an account for downloading.NIST viewer works but it wants to mess with my protected folders and has a user inteface that is "a bit cumbersome". Italso opens a browser to some NIST resouce page. I searched and found several but either they have become payed versionsOR they require creating an account OR they are simply defunct.Q2==I have for a long time used the Pentalogix "ViewMate" free gerber viewer. It does the job OK and it can interpret Gerber files withvarious settings for precision and standard (Metric/Inch/Mill). But it cannot "decode" drill files - even though they are created using the samestandard, like eg. Metric 4.3. Omitting/Including leading or trailing zeroes does not make any difference. A displayed file ends up with totallywrong scaling.There are "on-line" viewers out there but these are absolutely out of the question because of NDA's signed with my customers.

author: langwadt
author_rank: Super Contributor
timestamp: March 02, 2024, 04:08:27 pm
content: Quote from: Uky on March 02, 2024, 03:53:22 pmfreecad and kicad can probably do it, but if your customers are big enough that they required signed NDAs why does it have to be free?

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 02, 2024, 11:01:32 pm
content: FreeCAD works fine for viewing STEP files, although its UI is quite horrific. To each their own.And yes, KiCad's Gerber viewer is ok too. You can use it standalone. There's also gerbv. You can also consider ZofzPCB,https://www.zofzpcb.com/, which is quite good, but Windows-only for now, if that matters (and it doesn't run properly on Wine).

author: Smokey
author_rank: Super Contributor
timestamp: March 03, 2024, 12:01:26 am
content: gerbv for gerbers.STEP:https://www.eevblog.com/forum/projects/free-3d-model-step-file-viewer-i-can-recomend-to-customers/https://www.eevblog.com/forum/eda/free-step-viewer/

author: abeyer
author_rank: Frequent Contributor
timestamp: March 03, 2024, 01:28:14 am
content: For step (and other 3d cad formats):https://github.com/fougue/mayo

author: Uky
author_rank: Regular Contributor
timestamp: March 03, 2024, 11:08:58 am
content: Tried KiCAD viewer a few yars ago. Unfortunately it failed displying a gerber file that I used for testbut that was an early version 7. I filed a bug report but went back to Viewmate. But I will try a v 8 again.Have downloaded the other suggestion and will try those as well.Thanks for the links.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 03, 2024, 10:10:19 pm
content: Quote from: abeyer on March 03, 2024, 01:28:14 amJust tried it, very good, and snappy. I had required dependencies already installed, so the app itself only takes about 3MB. It will definitely replace FreeCAD for viewing STEP files (and others).The only downside I found with it is that it uses a custom file chooser dialog that doesn't support UTF-8. Not a big deal, but just mentioning it.

author: Uky
author_rank: Regular Contributor
timestamp: March 06, 2024, 06:59:12 pm
content: ...Tried the Gerber viewer in KiCAD V8.0 with a set of files created by Cadence Allegro.The Pentalogix Viewmate displayed the files correctly but KiCAD did not.The precision was metric, 4.3 Should have been no problem with that.I had created the layers for Assembly for a board with components on both sidesand therefore created the assembly file for the bottom layer mirrored. Otherwisethe board contour which was a complex one with irregular arcs and odd angleswas identical - except that it was mirrored.Surprisingly, KiCAD displayed one of the files correctly but failed all together withthe other one. Most arcs was extended beyond readability.KiCAD also failed in displaying the drill file correctly but then no other (free) tool that I have triedhave managed with that.So - back to Viewmate.Will try the mayo STEP-file viewer.

author: selcuk
author_rank: Frequent Contributor
timestamp: March 06, 2024, 07:47:40 pm
content: I'm using KiCAD for PCB design but the gerber viewer of the gEDA Project (gerbv) is better at displaying gerber files. I suggest you to try it instead of KiCAD. And it is possible to transform (rotate, move, etc.) layers with gerbv. Make sure you set the "rendering type" to "normal" or "high quality" instead of "fast" to view the files 100% correct.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 06, 2024, 11:33:48 pm
content: If you're not allergic to an online viewer, you can use this:https://tracespace.io/view/It's open-source, you can disable the telemetry. It's not a replacement for a complete viewer with measurements and all, but it renders your Gerbers automatically and is handy for quick checks and making pretty images.You should be able to use is purely locally, the source code is there:https://github.com/tracespace/tracespace

author: nctnico
author_rank: Super Contributor
timestamp: March 07, 2024, 01:28:52 am
content: Quote from: abeyer on March 03, 2024, 01:28:14 amThat works OK to view but measuring distances doesn't seem to work that well.

author: Infraviolet
author_rank: Super Contributor
timestamp: March 08, 2024, 01:08:08 am
content: For gerber viewing on Linux there's gerbv as well as KiCAD's gerber viewer. It's in the Linux Mint repos.https://gerbv.github.io/I use it alongside KiCAD's gerber viewer when I want a second-opinion on gerbers before sending for manufacture.Apparently there's a Windows version of it too.For STEP I'd say FreeCAD too, but if you really hate the interface of FreeCAD, you can always import the step there, then straight away export it to stl which gives you a much wider range of programs to view it with (obviously without any labelling, colour or automatic dimension measurement you might get from a STEP file).

author: nctnico
author_rank: Super Contributor
timestamp: March 08, 2024, 04:37:42 pm
content: The downside of Freecad is that loading a big step file takes forever. A quicker route could be using Mayo to do a conversion to STL.

author: Feynman
author_rank: Regular Contributor
timestamp: March 16, 2024, 06:23:42 am
content: I'm also using FreeCAD for viewing STEPs (since Design Spark Mechanical removed STEP support in the free version) and KiCAD Gerber Viewer.

author: aliarifat794
author_rank: Regular Contributor
timestamp: March 26, 2024, 03:40:51 pm
content: You can check PCBway online gerber viewer. It does not require downloading. You can upload your Gerber and drill files to render your board. ZIP files work, too.https://www.pcbway.com/project/OnlineGerberViewer.html

author: PlainName
author_rank: Super Contributor
timestamp: March 27, 2024, 04:09:45 pm
content: As another data point...I use gerbv and really wish I wasn't. Major hassle with it is the lack of native file dialogs, so every damn time the thing opens, to get to gerber files I have to click, in turn, 'projects', 'xx-yyyy project name', 'pcb', 'xx-yyyy pcb name', 'outputs', 'Gerber'. Every bloody time it opens in the installation folder and since the dialog is not native it doesn't respond to any of the great utils that quickly get normal app dialogs to the folder of interest. I am just completely pissed off with having to manually navigate the folder tree using a shit foreign file open dialog.Other than that, I guess it works. For copper - no holes or slots. Come to think of it, I have no idea why I am using this thing! Maybe I can find something better in an earlier post.

author: kripton2035
author_rank: Super Contributor
timestamp: March 27, 2024, 05:05:15 pm
content: the bamboulab studio app for their printers (and others too) can open step files.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 28, 2024, 12:01:29 am
content: Quote from: aliarifat794 on March 26, 2024, 03:40:51 pmNote that, as is obvious by just looking at it, PCBWay uses tracespace, which I mentioned above. You may as well use the tracespace website itself, which has better odds of using the latest version of the renderer, and also probably better odds of respecting your privacy. Just a thought. So all in all, using the one on PCBWay's website is fine if you're going to order from them, otherwise, there's no real point.

author: PlainName
author_rank: Super Contributor
timestamp: March 28, 2024, 12:35:30 am
content: I'm against using an online viewer because I'll have spent some time to find something that works, and there is no reason for it to then not work. Don't have to think about it: just fire it up and view the files, and it will always work the same way, and the files will always view the same.With online stuff you never know (and can't control) how the thing is going to look next time you use it, how to use it, how it will view your files (including ones you've already viewed), etc. Murphy's law says it will be the worst experience just when you need it to work at its best.

author: SiliconWizard
author_rank: Super Contributor
timestamp: March 28, 2024, 12:49:47 am
content: With tracespace, it's open source and I think you can run it locally. (You just probably need to run a small local webserver.) The rendering is really good and I have never been able to fault it so far.But, this kind of renderer is more for getting a subjective, and "pretty" view of your Gerber files - there is no measurement tool, no list of apertures, just images.

author: PlainName
author_rank: Super Contributor
timestamp: March 28, 2024, 01:16:25 am
content: You might be able to in theory, but in practice it's simpler to install all of Kicad just for the gerber viewer.Hmmm. Yarn. Aren't dev tools used by more than two people nowadays? For any random project you seem to need to learn a new set of opaque apps and setups.

author: HQ
author_rank: Newbie
timestamp: May 29, 2025, 08:41:40 am
content: Pardon the late discovery— this is a free and useful Gerber viewerhttps://www.nextpcb.com/free-online-gerber-viewer.htmlIt’s relatively new, appeared in recent years. From what I can tell, it's independently developed rather than built on third-party APIs. No registration is required, which makes it more privacy-friendly.

author: PlainName
author_rank: Super Contributor
timestamp: May 29, 2025, 09:12:39 am
content: Thanks for the pointer. The URL you gave has a trailing . which provokes a 404. Here's the working link:https://www.nextpcb.com/free-online-gerber-viewer.htmlAs for privacy, lack of registration might protect your personal details sending your private project info to a web page is... brave.

author: tooki
author_rank: Super Contributor
timestamp: May 29, 2025, 09:23:43 am
content: I’ve been using CAD Assistant as my quick STEP viewer for years:https://www.opencascade.com/products/cad-assistant/It is free, no account, and runs locally.

author: shabaz
author_rank: Frequent Contributor
timestamp: May 29, 2025, 11:51:40 am
content: Incidentally, regarding a comment in the first post, ViewMate can decode the drill file just fine (otherwise the software wouldn't be functional!).It is extremely unintuitive/clunky software for new users, but does work quite well. The screenshots show an auto-import from output files generated by KiCad (the drill format was automatically detected, with no user interaction). With other CAD software generated files, I do find I occasionally need to manually set the drill file format in ViewMate to match, which is annoying, but does work.The drill file does need to be manually assigned within the layer organizer, at least, I find that to be the case. Maybe it can be set as a default, but as mentioned the software is quite unintuitive, many settings have unexpected names since the software seems to be written from the perspective that the user understands Gerber and drill file content to some detail that a normal hardware engineer (not PCB designer) might not need to know.I'm not suggesting this software is more ideal versus the other suggestions and besides it's not free at a more functional level (but is low-cost, for the 'deluxe' version), but as mentioned it does function (and I like it, although I also sometimes use the KiCad viewer too).