1
$\begingroup$

If you are printing an object that has a base (A statue or trophy, for example), and presuming that you have already optimized every other setting: which shape of base would give you the best and most consistent bed adhesion when using PLA on the widest range of printers (For example, if you're putting it up on a site for anybody to download)?

For example:

  1. A square base that is thin at the edges and thick in the middle, and slopes upwards in the center, like a pyramid.

  2. A circular base that is thin at the edges and thick in the middle, like a dome

  3. A flat thick square.

  4. A flat thick circle

Is a shape with corners better, or a shape with no corners like a disc or a fried egg?

Do sloping sides make a difference, or general thickness?

$\endgroup$
1
  • $\begingroup$ I'm not having problems with adhesions, I'm trying to figure out the best shape that I can use for content that's going to be distributed online, so needs to be suitable for a wide range of printers. $\endgroup$ Nov 6 '21 at 8:26
1
$\begingroup$

On a heated bed the ideal setting is where the plastic becomes sticky, but not hot enough it changes shape. For PLA that's usually around 60 °C.

You want enough plastic on the build plate to stick to it, but not so much it won't come off. Use support to increase cIf the majority of the bed is covered it might stick too much.

My rule of thumb is to look at the shadow the part casts on the plate when lit from above. That's about the right amount. If it's too small or too large use supports to adjust the contact with the bed.

$\endgroup$
1
$\begingroup$

Plastics that shrink a lot (like ABS) do better with a base plate shape that has no corners. One approach is to put a one layer circle on every corner (ears).

PLA has a very small shrink factor, so there isn't really much of a difference for different shapes for the first layers as long as there is enough area in the base for the height of the part. If you are having problems with adhesion and PLA, either your first layer height is off or something is wrong with your build surface.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.