Higher brim  

  RSS
matzenotte
(@matzenotte)
Active Member

Printing with nyylon is not easy as everybody knows. Warping could be better reduced when having the possibility to print a brim that is higher than only one layer. Should be easy to implenemt in the slicer. Until now I have to design the brim om my own with the CAD software. What about thaf feature?

Posted : 23/01/2021 2:59 pm
airscapes
(@airscapes)
Eminent Member

New to PS but do this all the time in S3D and PS has the same settings.

Number of loops

Distance from Object 

Skirt height.. 

So if you want 4 loops .02mm from objects and 4 layers tall

Hope that helps.

Posted : 23/01/2021 3:25 pm
Area51
(@area51)
Prominent Member

Yes a higher brim size would be handy with some prints, also helps with the part attachment.
You could suggest it as a Feature Request issue at GitHub.

Have a look at my designs on Thingiverse or on PrusaPrinters ;)...
Posted : 23/01/2021 5:13 pm
bobstro
(@bobstro)
Illustrious Member

There is already a feature to print a draft shield. Not at my desktop to check the setting name right now, but it's under print settings.

Info here.

This post was modified 1 month ago by bobstro
My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 23/01/2021 5:27 pm
Neophyl
(@neophyl)
Noble Member

Already been requested https://github.com/prusa3d/PrusaSlicer/issues/2605 from 2019

Posted : 23/01/2021 5:56 pm
matzenotte
(@matzenotte)
Active Member

please don't confuse brim and skirt. Depending on the geometry a skirt is not connected to all sides of the part. So a higher skirt is not the solution.

@neophyl

request from 2019, can I vote for that? Should be easy to bring that feature to the slicer. Don't know why to wait for more than one year.

Posted : 24/01/2021 3:29 pm
Neophyl
(@neophyl)
Noble Member

@matzenotte

You can add or vote however you like.  As to why so long, well there are over 1800 open issues currently and over 3600 closed issues.  Its up to Prusa what gets priority.  As one of the developers posted on that issue its use case is minimal, there are workarounds etc already so its not really a high priority. 

As for a 1 layer brim being difficult to remove from the bed, its attached to the part and so comes off with the part.  So its not difficult to remove at all.  Unlike the base layer below support structures, now that can be a pain in the rear to remove.

Posted : 24/01/2021 3:40 pm
airscapes
(@airscapes)
Eminent Member

I am totally confused.. what do you actually want?

A brim is nothing more than a skirt that is attached or almost attached to the part.

If you click advanced  settings > Brim/Skirt tab > 

You can set the number of loops I would choose 4 or 6 depending on nozzle diameter

Distance from object is what will change a skirt into a brim.. Enter .02mm this will be close enough to stick to the part but you can still get it off without too much probem.

Skirt height, set that to as many layers high as you want it. 

Does this give you what you are looking for???

Posted : 24/01/2021 4:11 pm
Peter M
(@peter-m)
Prominent Member

Possible a way:

Import model,

right click on model,

add square,

make the square sit under your model, and make it thin,

the square, if you move it under the model, the model will go higher, and you can print with a square layer under model,

if you leave space between model and square, then it will fill up with support.

Posted : 24/01/2021 4:17 pm
Neophyl
(@neophyl)
Noble Member

@airscapes

A Brim in not a skirt.  While similar they are different things and are 2 separate items as far as the slicer is concerned.  

For example if you add a skirt, set the number of loops to say 8 and set the distance to 0 you seem to expect that the skirt will be attached to the part.  I invite you to try that and examine the slice preview carefully.  The skirt even with a distance of zero is NOT attached to the part.  Even with a simple test cube.  There is a gap between the object and the skirt.  You can not set a negative distance to bring it closer.  As such it does not function as a brim.  A brim is designed to increase bed surface area for part adhesion.

Now add a second object to the plater and position it .  The skirt now surrounds both objects boundary.  There is nothing in the space between them.

Compare that to the function of a brim.  Its surrounds each part on the plater with its own brim.  In fact that is also a github request as at the moment brim cannot be applied to only one or some objects, it applies to all objects in Prusa Slicer (one of the reasons I prefer Super Slicer as it can be set per object but that's besides the point).

While Brim could be improved several ways as it does have shortcomings, the need to make it multiple layers thick is not a major one of those.  If the brim is attached to the part properly then it will come off with the part correctly.  If it isn't attached to the part then its not really serving its purpose of improving part adhesion is it.  If its too attached to the part then its difficult to remove. 
At the moment this is controlled purely by how much you have your set Elephants foot compensation.  As the brim doesn't move but the first layer does it is the only thing controlling how well it is attached.  As squish can change with material choice or even if your bed is leveled warm or cold this isn't ideal.

Some of the current shortcoming of the brim function are -

-Brim to part distance is set by elephants foot value, it would be better to configure a specific brim offset distance and move it in with the first layer.  That way the distance of the brim from the part is independent and constant.

-External perimeters can get a brim but the interior can not (for example printing a cylinder/tube upright you cant get a brim on the inside which is desirable in many use cases.

-Nested parts - if you nest a part inside another part then anything placed inside the outer part will not have a brim generated for it.  I'm sure that when the auto arrange function gets updated to take nesting into account that the brim function for that will get looked at (hopefully).

-Its a global setting and not available on a per part basis.

-Brim goes around the whole part, it can not be set to only go around features that exceed a certain angle (for example its often useful for a brim to be applied only to 'pointy' features like with a classic mouse ear

That aside the brim is a very useful function even as it is.  

Posted : 24/01/2021 4:45 pm
Alex Hung liked
airscapes
(@airscapes)
Eminent Member

Forgive me, this works as I describe in S3d and I use it all the time with Nylon.  I have found PS to be so much like S3d I just assumed it would do as you ask it.. Seems to me making skirt  touch the part when you tell it zero would fix be a  good route to take but they are different products.

 

This post was modified 1 month ago by airscapes
Posted : 24/01/2021 4:54 pm
bobstro
(@bobstro)
Illustrious Member

For something with such a specific use, I'd go the "mouse ears" approach similar to what @peter-m-3 alluded to. Create a ship of whatever shape, and thickness you desire, then position it to the bottom of the print. You can make it whatever thickness you want and it is part of the print, so not subject to elephant's foot compensation.

My notes and disclaimers on 3D printing and miscellaneous other tech projects
He is intelligent, but not experienced. His pattern indicates two dimensional thinking. -- Spock in Star Trek: The Wrath of Khan...
Posted : 25/01/2021 1:49 am
airscapes
(@airscapes)
Eminent Member

Making the slicer obey Skirt .02mm from part is the simple fix.. 😊 

 

Posted : 25/01/2021 4:07 am
Neophyl
(@neophyl)
Noble Member

@airscapes

As posted previously it is not that simple. Making that change would work if all you had was a single part on the bed but that is often not the case. 

Posted : 25/01/2021 6:02 am
airscapes
(@airscapes)
Eminent Member

@neophyl

Ture, it can be a problem if you had mixed models. 

Still think it should be a functional option,  I had to use S3D to slice some tiny parts I needed to print in ABS and did not want them to come loose.

 

Posted : 25/01/2021 1:23 pm
Share:

Please Login or Register