Do Sellers here add Support bars in their designs for 3d printing or its upto buyer?

Lots of different 3D printers and printing techniques out there, some even don’t need supports.
For example SLS and jet fusion use layers of powder that automatically give support (that's probably main reason you see rings do not have supports)

Resin printers on other hand pull the model out of a liquid resin, so that needs a different type of supports then classic additive printers, etc.

Every printer comes with its own software and functions for adding support materials, its different depending on the printer model and printing process.

Its up to you how many printers and processes you want to specifically support out of the box.

Personally I just provide the models in the common formats and see to it that they have no errors (are water tight, have no flipped normals, etc.) and leave the rest to the user.

many of the people told me that. just design your work. repair Your STL make sure no there is no errors. but dont add errors. its upto user. i think thats what most people do. Thanks for your reply mate

I do not add supports. It's impossible to know if the customer will use the model for SLS printing or not (SLS does not require supports and can print much finer details). Or if they will use the model for some other reason. Supports would have to be edited out, which would be more difficult than adding them in.

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