Support Blocker for Dummies

[wayoutwestmultimedia 0]

Fairly new to 3D printing, and discovered that by not using support blockers, Cura tends to go crazy with supports. Not entirely a bad thing as the prints thus far look amazing... BUT, my knuckles are getting torn up removing supports.  I've watched several videos on using them but still can't seem to wrap my head  around it.\

 

For example, I'm trying to print a Mandalorian Jetpack which looks pretty straightforward.  When I use "TREE" method, it looks like a mutant fungus has overtaken the model. I try to use blockers so it only creates supports where obviously needed, but they are still there.

 

Again, totally newb to 3d printing but would love any "effective videos" or tutorials that would steer me in the right direction.

 

Cheers!

[GregValiant 1,409]

I can't suggest any videos that might help.  One of the problems is that all models require something slightly different.  Here are a couple of thoughts.

• The maximum overhang that can print at .2 layer height and .4 line width is 62°.  That means if you set the "Support Overhang Angle" at 55° to 60° you should be OK for most situations.
• Not all models are suitable to be supported with "Normal" supports.
• Not all models are suitable to be supported with "Tree" supports.
• It isn't always obvious where the support blocker should go.  Generally it should cover the "red" that indicates an overhang, but a support can grow and look like it isn't supporting anything.  There will be something up there though.
• If you use Lines, Grid or ZigZag as the support infill then you can enable the "Connect Support Lines" option.  That can make for a lot less retractions within the support.
• In the Material settings - if you set the Support Flow and the Support Interface Flow to 85 to 90% the supports will be weaker.  You will need to experiment to find what percentage works best for you.  Weak supports can be easier to remove.
• In most cases you will want to insure that the Support Interface goes down with the Layer Cooling blower on 100%.  If you are printing a material that is prone to warping then you should consider going in and hand coding some M106 S255 lines into the gcode.  You can turn the blower up high for the interfaces and then dial it back down when the nozzle moves to another feature.  The effect will be that the "roof" going on top of the interface won't stick so well.
• A set of "pics", needle nose pliers, a hobby knife, and micro-files come in handy for removing supports.  I keep band-aids handy as well.  The knives are sharp and can slip.

There are about 73 settings in the support section.  Add in those two Flow settings and you have a nice even 75 settings.  It takes a bit to figure out how to configure those settings to work together to do what you need.  Just keep making changes and slicing to see how it looks.  I almost always block supports from horizontal holes that are under about 20mm.  They always close up fine without needing help.  That's the sort of thing you pick up after a bit.

 

Edited August 30, 2022 by GregValiant