topic Re: Automatic Soldermask on Vias in Fusion Electronics Forum

Automatic Soldermask on Vias

sh9WZ6F — Fri, 23 May 2025 09:29:59 GMT

Hi,

first of all, it is nice to see that Fusion Electronics has been developing so fast in the recent month. 😁

But sometimes bugs sneak in, and features are overlooked to be compatible with these changes. 🐛

With the recent changes to Solder Mask settings in Vias, there seems to be a new bug implemented.

The Solder Mask setting now contains the Options "Auto", "Off", "Offset". (offset is new)

This change broke two different functions.

1. The Soldermask-Setting Auto was influenced by the Limit-Value in the Mask-Settings.

Now with a Limit value of 0.3mm, a Via with 0.2mm drill diameter is still covered by solder mask.

2. The Change Tool has an option to change the Solder Mask setting of objects.

Now this Tool does not interact with Vias anymore.

So at the Moment, the only option for me to change the Solder Mask on Vias is to manually open their properties, klick on the dropdown and select "Off".

Since I have to change this for around 200 vias, this is a tedious task.

Is there any way to change the Solder Mask settings for multiple Vias?

With the "Design Manager -> Filter" I can list all Vias or other Objects including the setting I want to change.

Unfortunately the "Design Manager" gives no option to mass edit settings.

I am sorry to say, but Fusion still is a lot frustrating sometimes. 🙄

Thank you in advance

Sebastian

Re: Automatic Soldermask on Vias

jorge_garcia — Fri, 23 May 2025 20:15:06 GMT

Hi @sh9WZ6F ,

So the change command does need to be updated and there is an open ticket for this. The soldermask behavior is currently by design, but that design is confusing. We have tickets open for this and are working to make it more intuitive. To help you right now, here's what you need to know.

1. Auto is basically an always ON

2. Limit will only work when Soldermask is set to OFF

So for now the recommendation is to set Limit to 999, effectively disabling it. Under these circumstances off will give you a tented via and Auto will give you an exposed copper via(pad). You can use the INSPECTOR in combination with the Selection Filter to select a group of vias then in the inspector you can control the soldermask settings for all the vias.

Let me know if there's anything else I can do for you.

Best Regards,

Re: Automatic Soldermask on Vias

sh9WZ6F — Mon, 26 May 2025 06:46:07 GMT

Hi @jorge_garcia,

thank you for your quick response.

So, as I understand, "AUTO" is default to all vias and there is no way to turn off Solder Mask for Vias with "AUTO" setting?

Is there an easy way to change all Vias Solder Mask to "OFF" or do I have to replace all Vias / Change their Solder Mask to off, manually?

Will Vias in older documets change to Auto, if I open or edit them?

Thank you in advance.

Sebastian

Re: Automatic Soldermask on Vias

pal.szabo — Mon, 26 May 2025 21:41:18 GMT

Hi Sebastian,

I experienced the same problem and might even be responsible for one of those tickets. 😀

"So, as I understand, "AUTO" is default to all vias and there is no way to turn off Solder Mask for Vias with "AUTO" setting?"

As of the current mainline release, this seems to be the case.

"Is there an easy way to change all Vias Solder Mask to "OFF" or do I have to replace all Vias / Change their Solder Mask to off, manually?"

Jorge gave me a tip on how to change them all easily. Set the selection filter to vias only, then select everything in the board (you may want to use Ctrl+A). In the Inspector window you can sort based on the solder mask and select all that are set to Auto. Then you can change them to Off so that they respect the Limit setting.

"Will Vias in older documets change to Auto, if I open or edit them?"

In my experience they do not. I was working on a board when the update happened and it kept all vias already placed set to Off, while all newly placed vias became Auto. Imagine my confusion. 😀

Pro tip: it might be worth putting on your board checklist to convert all stop masks for vias before sending the board to the fab house, because it's really easy to forget.

Best regards,

Paul

Re: Automatic Soldermask on Vias

sh9WZ6F — Tue, 27 May 2025 07:35:44 GMT

Hi @pal.szabo,

Thank you, a lot, this helped me to understand how the board inspector works.

I never used this tool before and wondered why I cannot change these properties within the design manager.

Now I learned that the board inspector is made to change these settings. 😄

Best regards,

Sebastian

Re: Automatic Soldermask on Vias

timonsku — Tue, 05 Aug 2025 19:11:23 GMT

@jorge_garcia is there any plan to fix this anytime soon? This has caused quite a lot of work in recent months. I never want exposed vias and with the current behavior of "Auto" effectively meaning always enabled I have to manually change vias to off, every single time I place a via. The dialog does not remember my last setting so it will always revert back to Auto when I set it to off in the last placement. Either fix that Auto generates soldermask openings despite not exceeding the limit or let me define my own default. The current way is kind of mind boggling, I don't know who would possibly want vias exposed by default.

Re: Automatic Soldermask on Vias

jorge_garcia — Tue, 05 Aug 2025 21:11:48 GMT

Hi @timonsku ,

Oh man, I'll keep reporting it. The workaround in the meantime is to wait till you've placed all the vias and then use the selection filter and inspector to set all the vias to off. Doing it every time you place a via will drive you to madness.

I'm really sorry about this, I've reported it and that ticket is getting updated every couple of weeks. I hope we'll have a resolution soon.

Let me know if there's anything else I can do for you.

Best Regards,

Re: Automatic Soldermask on Vias

timonsku — Tue, 05 Aug 2025 21:16:35 GMT

Thanks for the quick reply @jorge_garcia . Good to hear its at least worked on.
The workaround reduced the work but the big problem is consistency, its hard to spot if you accidentally created a new via with a reroute and only find out after the factory complains about an unmasked via. So this is a big design "safety" issue where I can currently not rely on the my design setting providing me with a safe to fabricate design.
I hope it will get escalated further internally as that is definitely more than just an annoyance right now.

Re: Automatic Soldermask on Vias

coyt.barringer — Fri, 08 Aug 2025 00:55:04 GMT

As a long time user of Eagle & now Fusion360 PCB - I want to add on here how critical this is to fix ASAP.

I experienced this problem a few months back - the completely broken "Design Preferences -> Masks -> Limit" tool that I have literally used for years.

Many times now I have gotten all the way to uploading a set of gerbers to JLCPCB only to look at their gerber renderer in the browser and realize there are stop masks incorrectly placed over my vias!

In the past, I found this thread or a similar one, and can successfully apply the fix via the selection manager and the (change -> stop -> group) method. But when you work on designs weeks or months apart, you forget things. Today, I forgot how to fix this issue but I remembered enough that I already knew it was a bug I had encountered weeks earlier but had to spend time searching for the work-around fix. That is pretty bad....

Re: Automatic Soldermask on Vias

timonsku — Fri, 08 Aug 2025 01:30:48 GMT

Exactly that. It also worries me a bit about how much ressources Autodesk is giving the Electronics Team if something so basic and integral can be an active bug for months. Even just reverting to "off" as default would remedy the problem.

Re: Automatic Soldermask on Vias

coyt.barringer — Fri, 08 Aug 2025 02:52:56 GMT

I don't care to currently think through their logic with this setting right now, so I agree all that is needed in short term is the default via "solder mask" behavior be set to "off".

I really simply want the Design Rules -> Masks -> Limit rule to actually work properly.

Eagle and now Fusion 360 PCB has always had quirky issues...i could list a dozen such issues.... most PCB design software does... so nothing new or earth-shattering there. It's more a side effect of not having actual designers and users test out new software before release, but unfortunately that's common practice these days. For example, If I counted the number of clicks it takes to make a new library part with a 3D model... we in for a treat.

What makes a good company and product IMO is how they respond to bug submittals like this. Ideally, we'd be provided details and updates of their resolution plan. @jorge_garcia says there are tickets to tackle this already being tracked. So... when is the estimated update to fusion360 which includes these fixes going to be deployed?

My guess is the answer will be nebulous. because no one wants to commit to anything or take any risk these days. And even if the estimate was years... that would be a better response than a nebulous one. because then at least I can commit to memory, or a macro, the workaround i must do each time for this problem.

Re: Automatic Soldermask on Vias

sh9WZ6F — Fri, 08 Aug 2025 14:11:14 GMT

And I just noticed today, that the tool "change --> Stop" still only has the options "off" and "on" and so does not work with Vias anymore.

Is there anything I can use this tool for?

I think this is known for month too.

Re: Automatic Soldermask on Vias

coyt.barringer — Fri, 08 Aug 2025 14:45:29 GMT

@sh9WZ6F I can still successfully use the selection filter to highlight all my vias, go to the change tool, go to "stop", make sure "off" is selected, then right click off my board somewhere to change the entire group setting of all the selected vias to switch the solder mask from auto to off for all of them. for me at least, this gets the behavior I am looking for which is to remove the stop mask over the vias so they get properly covered by green soldermask at the boardhouse.

Actually that is really weird - I think I see what you're saying - I cannot click one single via with the change tool selected - even if stop -> off is chosen - and have the Solder Mask setting change away from auto. it seems stuck on auto - well specifically - that change tool setting has no effect. Only if i manually highlight the vias I want first, then go to the change tool, then right-click somewhere do I get the option to turn the soldermask setting off via change tool. This is not the case for change tool -> drill size for example. If i do that, i can freely click vias and they change size properly.

Just to add one more thing so autodesk can track this issue fully - this issue is sort-of extra bonus problematic because the default behavior when you "Push To 3D PCB" at-least on my system with the latest updates is to have "Stop Layer Geometry" NOT SELECTED! so if you leave the push to 3d setting defaults it will not show you this problem! your vias will look proper leading to a belief that all is good until you get to production. If you check "Stop layer Geometry" specifically, then push to 3D, you will see your vias have improper soldermask stop layers placed over them leading to exposed via metal during production.

Re: Automatic Soldermask on Vias

jorge_garcia — Fri, 08 Aug 2025 23:13:45 GMT

Hello @coyt.barringer and @timonsku and @sh9WZ6F ,

I've elevated this again. The full solution has been determined but will take time, I've put in the recommendation to as a stop gap return to the old behavior.

Let me know if there's anything else I can do for you.

Best Regards,

Re: Automatic Soldermask on Vias

anthonyEX9NB — Tue, 02 Dec 2025 14:46:15 GMT

Wow! This operation is bonkers. Shouldn't the Solder Mask = Auto setting for a via mean that the solder mask is generated in accordance with the Preferences > Masks > Limit setting, and the Solder Mask = Off setting means that the solder mask for that via will never be placed? And if the designer wants the solder mask for a via to always be generated regardless of the Preferences > Masks > Limit setting, then please add a Solder Mask = On setting.

What does the Solder Mask = Offset setting do?

And I ditto a previous poster who pointed out that the Change > Stop function only has 2 options: on and off. And that's confusing because there is no "on" setting available when you place a via.

Let's go, Autodesk. Get this figured out!

Re: Automatic Soldermask on Vias

jorge_garcia — Tue, 02 Dec 2025 20:08:05 GMT

Hi @anthonyEX9NB ,

I hope you're doing well. This is a known issue which I have reported several times. It is being worked on and an intuitive behavior is forthcoming in the near term. I look forward to that with much joy.

For now you can still get it to achieve what you want but it's unintuitive. In essence:

Auto = Always On regardless of Limit settings
Off = Takes limit into account, anything larger than the limit value will exposed and have a soldermask opening

Offset = If the offset value is larger than the expansion calculated by DRC it will be respected otherwise this will just have the automatic soldermask expansion.

The Change command does need to be updated. It currently does not work.

Let me know if there's anything else I can do for you.

Best Regards,

Re: Automatic Soldermask on Vias

krugatech — Fri, 30 Jan 2026 17:04:52 GMT

Nearly two months later and after a new Fusion update the via-bug is still not solved...
I had to scrap a stack of already produced boards last year because an additional via between tightly spaced BGA pads suddenly opened up…
Please consider this post as a small reminder of how serious this bug is...

Unfortunately this bug (and also the Change > Stop tool, which does not show the new Auto option) gives every programmer a deep insight into how this software is being developed... And honestly, with every update, my trust in this program is diminishing… And I really find that a shame, because I like Fusion 360! I was genuinely excited when I heard that I could design both mechanical and electronic components in a single tool.

Re: Automatic Soldermask on Vias

timonsku — Fri, 30 Jan 2026 18:29:37 GMT

Yes, the trust issue is a really big problem with this. Bugs happen but something seems to go seriously wrong internally communication wise if this is not a highest severity issue, this is like having a text editor where by default everything you type is in bold and you have to manually go in each time to make sure you didn't miss undoing a fixed typo being left bold.
If I were to try out Fusion as a new customer I would immediately abandon my trial if I encounter something like that.
An improvement of making things more intuitive down the line is great but completely breaking a crucial feature and leaving it completely unaddressed for more than a few weeks is puzzling. Why is the suggestion of defaulting to Off for newly created vias for the interim not being implemented? This is such a simple change that does not affect existing designs in any way and would resolve the problem until something better comes along.

Re: Automatic Soldermask on Vias

jorge_garcia — Fri, 30 Jan 2026 23:03:04 GMT

Hi @krugatech and @timonsku ,

I keep pushing this up the chain. I know how critical it is and how annoying this workflow break has been. I followed up with our management and it looks like we'll be getting the ability to get the default set before the final fix of the entire soldermask system. That should be enough to be passable until the final solution comes in.

One thing @timonsku being able to set the default to Off will only give you tented vias if you also adjust the limit value in design preferences. I believe you know this but for other users I'm putting this in because it highlights just how crazy this behaves.

I'm pushing guys, it looks like soon I won't have to keep addressing this. Keep the feedback coming.

Best Regards,

Re: Automatic Soldermask on Vias

timonsku — Fri, 30 Jan 2026 23:10:11 GMT

Thank you Jorge, I appreciate your effort on this.
Being able to change the default would absolutely suffice in the short term. 99% of the time I care about vias being covered, not having the full function of the previous Limit behavior is not as crucial at the end of the day, I just need to ensure that vias are covered by default, manually changing the handful of plated holes that I want uncovered is not a big deal.