PR for multiple brims to exercise build agents

[lordofhyphens]

DO NOT MERGE. The UI is not well-tested and this has not been proven to actually solve the underlying problem the feature was requested for.

[lordofhyphens]

Experimental implementation for #641

[lordofhyphens]

@zapta @Pun-e @ellenpoe @foulowl Experiment to your heart's content and figure out if it actually solves the underlying problem.

[lordofhyphens]

this is probably useless now, but I am very bad at using XS to get a useful kind of reference.

[AppVeyorBot]

✅ Build Slic3r 1.3.0-master-2347 completed (commit fc28ba8fbc by @lordofhyphens)

[lordofhyphens]

Windows https://ci.appveyor.com/api/buildjobs/f55y9i7574adq9bt/artifacts/Slic3r-master.2019.07.07.2347.fc28ba8f.64bit-PR.zip

[ellenhp]

I've long since sold my printer and am firmly on team close-that-original-issue. Thicker layers and support should solve most build issues for most people and if appearance is an issue, there are other ways to solve that. Just my 2c. Unfollowing since I don't have much else to offer here.

[Pun-e]

So I've just received some new parts for my printer and I'm planning on printing them all in PC. I downloaded the provided test branch, can see the new brim height option, which is working as expected, but it seems to be very "fragile":

This was due to my re-arranging the parts.
The errors don't persist into a fresh launch, but there's definitely something going on that's causing issues with the skirt / brim generator. When I want to slice a file I have to relaunch it every time or I'll get all kinds of strange behaviour.
First load:

But if I change any parameter:

Not sure if it's just a difference in expected behaviour between the Prusa and main branches. I use background processing.
With regards to the efficacy of the multi-layer brim, I've only just managed to get a successful gcode and it's printing now

A good example of the failures I hope multi-layer brim will take care of:

A - Where the part has detached from the brim
B - The entire 6mm brim that was stuck so hard I damaged the PEI surface removing it

I have finished my muli-layer print, and can confirm once and for all that a multi-layer brim both works, and is useful. I started with a 4-layer brim, but that warped terribly. Then I tried with a 3-layer brim, which came out perfectly!

Cannot understate how happy I am with my first 100% true PC print. A side note is that the brim is also significantly easier to remove when it's thicker, as it will actually snap-off and not just split up and become impossible to handle.

[Pun-e]

MC_Shroud_Gcode.zip

This is a copy of a good gcode run, and a dodgy one. Seems like any change in the layout, or in skirt /brim options causes it to happen. This makes it incredibly difficult to use this release as after every change I need to close, re-add pieces, re-arrange, slice. If anything is NQR, repeat the process.

The brims themselves are functionally everything I was hoping for.

[lordofhyphens]

I did specifically say it was a hack.

It is probably having to do with the fact that the slicing pathway wasn't written with multiple layer brims in mind so I didn't get all of the places that assumed it.

[lordofhyphens]

@Pun-e export the plate with modifiers as 3mf or amf. It will be less of a headache to experiment with.

[lordofhyphens]

And to reiterate, the units for this will always be in layers. If someone needs it in mm they can refactor the thing to get what they want, because getting the units to be in mm is way more work than I am willing to put into it.

[Pun-e]

@lordofhyphens
So, I've spent a few hours and come across a few major errors:

• Sending to my networked printer will fail if the print is to big (unsure if this is standard slic3r bug)
• Moving / changing the parts after initial slice will fail
• Changing any brim / skirt option after initial slice will fail
• If you try to print more than object at a time, it just gets stuck printing the brims.

The only ones I really need to be functional is the "cannot slice more than once due to moving parts". I have all my settings dialled in, start, load parts, slice. But if the brim, or skirt is too far, or some parts look iffy all I can do is try again from scratch. If I could just get more than one slice per load this would be more than enough for the limited times that I need this feature.

The other major one is the inability to print more than one object at a time. The gcode looks fine, but for some reason my printer just never stops printing the brim. Have no idea if this is just me, or a bug with the slicer.
Update: A print from the sd card failed the same, so it's definitely something wrong with the gcode. From observation, it looks like it's printing a complete brim for every single object, which would explain the outcome when I go to check on it
Update 2, that didn't work either, it still printed one brim at each layer for every part, per part.

[lordofhyphens]

Normal behavior re: brims printing first. Brims are generated first. It is not appropriate to request a change to that behavior here (out of scope).

[Pun-e]

Normal behavior re: brims printing first. Brims are generated first. It is not appropriate to request a change to that behavior here (out of scope).

I'm sorry, I don't understand how this relates?

[eliliam]

Any updates on this? This would be an amazing feature to add, especially for the case mentioned above where the contact point between the brim and model is very weak, and adding additional layers may help it adhere better.