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Topic: bottle print

I printed this at .4 the the size.it It was a 12 hr print.  When it finished I noticed several gaps in the layers as you can see. I did the same at .2 and it did ok no gaps. Any thoughts why?

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SD3, E3D hotend,linear bearing on x/y axis',pillow block bearing on y conneting rod, ball bearngs on front y axis, fan on y stepper motor.

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Re: bottle print

Large parts will seperate if they cool too quickly. If you enclose the printer and keep it warm it should help. What temp was it printed at?

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Re: bottle print

Ambient air temp about 65F. I guess I'll wait til spring to make large prints as I do have cool room. EXT temp 195, bed 95
Would form core work? thanks

SD3, E3D hotend,linear bearing on x/y axis',pillow block bearing on y conneting rod, ball bearngs on front y axis, fan on y stepper motor.

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Re: bottle print

The nozzle diameter is .35, so the plastic extruded through it won't be very much bigger.  You can extrude into air a little bit and measure how wide it is.  At .4, it is almost getting dropped down onto the layer below, fully round rather than squished into it.  If you are trying to save time, you can do taller layers with a .5 nozzle.

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Re: bottle print

IanJohnson wrote:

The nozzle diameter is .35, so the plastic extruded through it won't be very much bigger.  You can extrude into air a little bit and measure how wide it is.  At .4, it is almost getting dropped down onto the layer below, fully round rather than squished into it.  If you are trying to save time, you can do taller layers with a .5 nozzle.


Exactly; and isn't it also true there is a optimal layer height for each nozzle hole diameter width due to that effect you spoke of?  I read somewhere that you can't really expect to get the best quality from .10mm small layers from a .35...it's always better to use a different nozzle slightly above the size you want to print vs trying to force under-extrusion or over-extrusion.  You can make the nozzles with brass nuts from McMaster's (I posted the link on here somewhere and you may find that useful)  I used .20 prints on my printer since I read about that extrusion to layer height relation and have had great results, but if I really wanted to push for different layer heights...I would change the nozzle first also.

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Re: bottle print

I think it was something like 85% of nozzle diameter.  One thing that you would lose from going to a small nozzle to print low layers is the thick first layer.  A .1 first layer can be tough to stick, bed level is so much more critical.   A interesting use for dual extruders would be dual nozzle sizes.  Have a .2 for the perimeters, and a .5 to run fill every 5th layer.