What could cause this?

[ScanHD 32]

Heloo everybody, 

My printer has been flat out on decorations and models for the kids this Christmas, but my latest print wasn't so successful... 

 

What could cause 3 out of 5 front right moose legs to fall off like that? All seem to have happened at exactly the same way. But 2 are uninjured. 

 

Any ideas? 

[geert_2 520]

Maybe they just came loose from the build-plate, and started to wobble? Edges on overhangs tend to curl up, and then at the next pass, the nozzle might brutally bang into those curled-up edges.

I am guessing here, but I have had something similar happen during overhang tests. See the pics: here they curled up ca. 1.5mm, for a layer height of only 0.1mm! Increasing the feet (the mickey mouse ears) and making them a little bit higher, should improve bonding. Printing cooler and in thicker layers, should reduce curling. At least, it did for me.

 

At least, it allowed me to make nice spaghetti photos.

 

 

 

 

 

[gr5 1,721]

If this is ABS filament then I have a different answer.  But more likely this is PLA and the legs are just not attached well enough to the glass.  Maybe add some gluestick and then thin the layer a LOT with a wet tissue.  You want a layer so thin you almost can't see the layer of pva glue.  Also maybe make the bottom of the feet a little flatter (there is an option in cura settings to not have it always set Z position to zero and then you can position the reindeer at -0.5mm).

[ScanHD 32]

thanks for the tips guys!

 

Yes the overhang may well be the culprit! kinda makes sense as where they fail is just where the overhang is starting to get big.

 

Indeed it is PLA, and i use a very thin layer of glue spread with a wet sponge i find works well. Im pretty sure its not bed adhesion issues as they are still well stuck to the bed when its time to remove them!

[cloakfiend 980]

I also agree, This has happened to me a lot, and tends to happen when joining the solo object to the main body. its the curled up edges simply getting knocked. and as the base is so fragile, it simply topples over. tends to be random, but also happens more when printing cooler. i think base adhesion is not that relevant, its the contact with the base being smaller than the join with the body causing this. if you turned the legs upside down it wouldn't happen as much. its the heavy head. this rarely happens on the um2 which has a much lighter head and not as much impact when it hits something.