Problem with wall thickness in single outline mode (spiral v

[nerys]

I like printing my rockets in spiral vase mode. not only is it much faster but its actually usable. nice flexible strong parts.

well today I am having a headache. I have a rocket I am printing off thingiverse.

I had to seperate and resolid it in 3d to get it proper but thats fine got a good outline tool path now for single outline mode.

SO

I enlarge the rocket 3 times my print bed height. and I print it in 3 pieces.

the bottom prints perfectly. the top prints "ok" the middle is so brittle and thin its unusable.

I change NOTHING in settings and since I am printing spiral vase mode it should not matter what portion of the model I am printing all walls should be the same since no settings are changing. but the middle is so weak its hard to even get it out of the printer without it coming apart in my fingers.

There is a HUGE thickness difference in the walls of the bottom piece and the middle and top piece.

what is changing and how do I stop it? I want it all "thick" like the bottom section.

attached is the factory file. my multiplier is .95 (stock the way simplify set it) in this file its 1.15 (I am trying to up it to see if that gets me thicker walls on the parts that print too thin) I will know in 30 minutes or so.

Here is a video on youtube clearly showing what I am talking about.

https://www.youtube.com/watch?v=FVmNem_5Z3Y

I just took my calipers to the parts and that explains everything but not a solution.

the booster is 1.02mm thick. perfect.

the middle is .48mm thick the top is .54mm thick (so .54mm is borderline I need that thick or thicker less and the part falls apart)

how do I make the walls thicker I assume extrude more plastic??? and why is this extrusion "changing" depending on what part of the rocket I print. in vase mode the part should not matter its single outline. ???

this also explain the part falling apart. not enough plastic is smooshing into the previous layer for a good "melt together" so it delaminates really easy while the 1mm thick part is damned near indestructible (reasonable expected forces)

any help is greatly appreciated.

simplify 3d outputs .factory files and the simplify 3d official forum won't accept .factory files. admins might want to look into that :-)

the attached zip is not a zip rename to .factory

[CompoundCarl]

Vase mode works best with very gradual changes in the part shape. You have some pretty steep overhangs with that center piece. If you are only using a single outline, that's going to be difficult to handle those large overhangs. So it is naturally going to be weaker than something that prints nearly straight up (like your other 2 pieces).

You could try decreasing the layer height which will help the layer handle overhangs better. Otherwise, you may want to just try printing that central section with multiple perimeters (i.e. disable vase mode) since it is special and has a tougher contour vs the other 2 parts.

[nerys]

the overhang is fine in fact those are the strongest parts of that model.

oddly enough I have partially found the reason for the problem but not a solution.

THOSE parts the weak brittle parts are closes to reality as far as printer settings go.

the settings were .95 and .4mm

that part is .48mm thick.

I changed the multipler to 1.0 and the width to .75 and ended up with a 1mm thick wall. why the difference? why not a .75 thick wall?

also when I had the previous settings .95 and .4mm why was one part .48mm and one part .54mm and one part .5mm on one end and 1mm on the other end of the same part?

why is it not the "same" width all around top to bottom IE what is my layer width changing MID PRINT and from one print to the next. ??

the XY precision is good. I just printed a tube at 1.0 and .75mm. insanely strong way stronger than I need (so more plastic and more mass than I need) so I am going to thin it up a bit (try .50mm)

but I did not get .75mm as defined in settings. I got .96mm

why?

also. the XY precision is good. the part is defined as 20.68mm and its almost spot on 20.68mm exactly. nice.

is there a way to define INSIDE diameter. I don't care about the outside diameter so much as I need the INSIDE diameter to be correct and consistent in vase spiral mode (so I can join parts together with couplers)

and I still don't know why I get varying layer width in the same print

Here is a good example of what I am talking about. I did a 3dbenchy. BIG variation place to place on the model.

the boat hull is immaculate. I mean perfection in extreme even the anchor holes. spotless

but once it starts making the cabin it LOOKS like over extrusion and then mistakes. it fails error 81 (jam but not a jam no idea why it does that)

I resumed and it RESUMED at perfection again. nice clean walls. slick.

once it started to do the smoke stack it starts off clean then goes to over extrusion (or whatever it is) and then back to clean and super clean at the end.

ahhh. driving me nuts :-) Lack of consistency is driving me nuts.

http://i.imgur.com/PMZsbbf.jpg

http://i.imgur.com/hoD9LWb.jpg

[KC_703]

I think you're just getting to know your machine.

What is the nozzle diameter? Typically the extrusion width should be between 105% to 170% of the diameter. So expecting a 1mm wall (spiral vase) from a .5 nozzle would be a stretch, IMO.

In a perfect world, you should get .75mm width if the multiplier is at 1, and extrusion width set to .75. If the actual extrusion width is 1mm, then the machine is overextruding. This could be a combination of things from inconsistent filament diameter to calibration of the machine. Sample the filament diameter throughout the spool and use the average diameter. Check the printer calibration by marking the filament at 100mm above the extruder, and extrude 100mm. The mark should have advanced 100mm, if it didn't then the e-steps are off and need to calibrated.

The following is a good guide to check calibration and some general wisdom.
http://reprap.org/wiki/Triffid_Hunter's ... tion_Guide

The following article really gets into the weeds of extrusion width:
http://manual.slic3r.org/advanced/flow-math

With that said, the world isn't perfect. So expect that even with a perfectly calibrated machine, filament composition may effect the extrusion outcome. I generally try to stick with one manufacturer, but have found that different colors may extrude differently. So in those situations, I'll adjust the multiplier until its producing accurate prints. My calibration print is a M5 thumb cap which I designed to be +.01 the diameter of the socket cap. The STL is attached, it should be fairly tight to get on the socket cap (remembering to line up the hex center).

As for your the Benchy, slowing down the printer should help accuracy. Every printer will be different. I've learned that my machine produces great exterior surface finish at ~40mm/s. So that's the target I shoot for when specifying perimeter outline underspeed. Find the best for your machine and use that as the underspeed goal.

I don't know what advice to give you on the the rocket model... If it were me, I'd calibrate the multiplier, set a known extrusion width, don't print with spiral vase, and let the slicer calculate these things. I suspect the extra weight of the plastic will reduce the efficiency of the rocket very little... you'll probably want a fairly rigid body to withstand deformations from forces associated with launch and aerodynamics.

Hope this helps you further learn more about your machine.

[nerys]

Thanks for the feedback.

I dont expect 1mm, I am getting 1mm even though its not set for that (would prefer .5mm)

.4mm nozzle

I used 2000mm/m and 50% underspeed to do the benchy.

The filament is crazy consistent. 1.69mm .02 variance. I am surprised by this being $13 a kg.

I have a feeling the printer has issues or simplify does not have full control of it (though far superior results to makerbot desktop) or both.

It sounds like makerbot is going to replace the printer for me (fingers crossed) slighlty bent z axis jack screw. I am also going to get the new extruder if i can.

I keep getting error 81 (filament) there is something wrong in the extruder where the gear just does not engage the filament.

This is nit the cause of my issues as that coukd only cause under extrusion.

How do i advance 100mm of filament? There are no controls on the printer. Can i do this somehow in simplify?

[KC_703]

To extrude 100mm, Machine Control Panel -> Jog Controls -> Extrude 100 button

May need to use the arrows to reveal the "Jog Controls" tab/panel.