Body coming away from the base of a vase

[markvk42 0]

Hi Im trying to print this:

 

https://www.thingiverse.com/thing:2203039

 

now i am new and this is only my 3rd print, but so far ive bee pretty excited about my results and am pleased with it all.

 

as you can see the top hasnt bonded to the base at all and im wondering how to fix the problem?

from what ive read even though ive set the wall thickness to 1.2 it will only print at 0.4 because i only have my line count set at 1, and as my nozzle is 0,4 thats what im getting.

 

However id like to keep the flexibility in the vase walls and if i make the walls thicker then  that wont happen. is there a way to start it with a thicker wall and reduce it down?

 

any help appreciated, thanks.

[gr5 2,168]

I don't know the answer.  There used to be a feature called "joris" and then I think it was called "spiralize" and then possibly "vase mode" and now there is a "spiralize" option again in cura but I'm not sure what it does.

 

At one point - before the year 2016, spiralize would thicken the base where it attaches to the walls.  I don't know if it still does that.  Both for strength and to make water tight.

 

I guess I recommend you just make the line width a bit thicker so it overextrudes as it prints.  I've never done a cup or vase so I'm not an expert on this kind of thing.  And maybe try out "spiralize" but it might make your vase worse.  Maybe try it on some very small prints (just half hour prints).

 

I think most vases are done with a 0.8mm or 1mm nozzle and with a 1mm to 1.5mm line width which should make it waterproof and stronger as well but again - not an expert.

 

@rooiejoris is an expert but I don't think he comes to this forum anymore.

[GregValiant 1,248]

Not in Cura but yes, there is a way to start with thicker walls and then narrow them down.  It's in "Advanced Gcode Splicing 401" so maybe you don't want to go there yet.  As gr5 says, you do need to thicken the walls.  With a .4 nozzle I've had good success with 0.6 line width.  Vase mode is "single wall only" no matter what the wall thickness setting is.

 

Another problem is that many Silky PLA's just have poor layer adhesion.  That problem can vary by color and might be what bit you there (nice looking print otherwise).  You may have to bump the temperature up as well.  I can run regular PLA down to 195° but silky I always start out at 215° but you could even run it up to 225 at the first layer above the base feature because there aren't any retractions and the print head never stops.  It would be really gooey though.

 

Be careful when removing it from the bed and try to get that first layer down without adhesives.  No matter what you do it's still a single wall print so it isn't going to be strong.

[markvk42 0]

Thanks for the help guys, i am using spiralise and im printing straight to bare glass, no hairspray or adhesive. im already printing at 215 with a bed temp of 60. i do have a range of bigger nozzles and will try one, first ill try a small print without spiralise and see how i get on.

[gr5 2,168]

If spiralize is on and wall width is 0.6mm and line width is 0.6mm and your nozzle is 0.4mm (nozzle is not normally a cura setting) it will extrude at 150%.  Your printer will try to squeeze out a 0.6mm line with a 0.4mm nozzle.  You can do that but you may need to print slower than usual. 

 

It depends how powerful the feeder is on your particular printer.  But on say an Ultimaker 2 you would have to print pretty slow but on the UM2+ you can probably do like 0.2 layers and 40mm/sec and 150% overextrusion.  Just guessing without looking stuff up.

[GregValiant 1,248]

That sounds about right gr5.  Spiralize takes the speed settings and adjusts them during the actual spiralized layers.  The base layers print at 100% feed rate.  When the spiral starts the speed drops to 50% and by the end of the print is typically at 25%.  So Cura is making speed adjustments layer by layer.  I printed an RC sailboat hull with the .4 at .6 line width but I thought in that case it just wasn't thick enough.  I'll be printing it again with a .6 at .9 line line width.  I don't want to sink a bunch of fairly expensive gizmos.

[GregValiant 1,248]

I printed a vase yesterday in silky blue PLA as a test.  It looked really good.  It came off the build plate fine (I use a small putty knife and tap it with a tack hammer to break it loose).  I presented it to the wife and forgot to tell her "dry flowers only".  That turned into another test as it leaked, but only at the transition layers between the bottom and the spiral.  That would seem to indicate poor layer adhesion or gaps there.

I may do a partial test with the flow kicked up for that transition and then drop it back to 100%.  Another leak test might indicate if that provides a better bond.  That is also the layer of the speed transition.  I happened to be looking at the printer when the transition happened and it was very sudden.  Maybe a gap occurred because of that.

[markvk42 0]

Hi Greg, i would be interested in your reults.

[GregValiant 1,248]

Well...it was my bad.  I had forgotten to remove "Pause At Height" from the list of plugins.  The leak was at the "resume" layer and not at the transition between base and spiral.

So the only thing the flow test showed was that I should have slowed the print head down (the extruder started dropping steps when the flow went to 110%) and it also reaffirmed that I'm a dummy.