MK3/s kit impressions and questions  

  RSS
boris.k8
(@boris-k8)
Active Member

Hi there!
I ordered on a Sunday night (early Monday in Czech) and it arrived Friday just five days later. Impressive.

Took my time to assemble the kit, but there was just one bag of Haribo in it. That slowed me down quite a bi. Thankfully my wife went to a 'specialty' store and got refills.

The extruder cable clip was missing though. No big deal. I printed that part later on. No issue.

First impressions -- the Prusa is a much better printer than my (modified) Anycubic i3 Mega. I love the auto level, no end switches, direct drive. almost silent. All that is very, very nice.

The only thing I cannot get my head around is this:

Any given object sliced with Simplify3D is about 30% faster to print as opposed to Silc3r PE. I compared the most important values and setup Simplify3D accordingly. A difference of a couple of minutes, I would not bother, but if a 2 hour print takes 3 hours through Silc3r - this is weird. Any ideas what that could be? It cannot be the printer. It has to be some G-Code difference but what? I compared the G-Code files and it is impossible for me to figure out.
Anybody having an idea?

Cheers.
BoKo

Posted : 21/03/2019 4:41 pm
JoanTabb
(@joantabb)
Moderator

are you looking at projected build time or actual build time?

Joan

I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK...
Posted : 21/03/2019 7:56 pm
boris.k8
(@boris-k8)
Active Member

Real actual print time as in watching the clock...

Cheers.

Posted : 21/03/2019 8:11 pm
JoanTabb
(@joantabb)
Moderator

fair enough, do the two models weigh the same?

Joan

I try to make safe suggestions,You should understand the context and ensure you are happy that they are safe before attempting to apply my suggestions, what you do, is YOUR responsibility. Location Halifax UK...
Posted : 21/03/2019 9:41 pm
boris.k8
(@boris-k8)
Active Member

I did not think of that. Unfortunately our postal scale is just a non metric thing and both come out at 0.5 oz.

Interestingly enough the "guesstimation" of both software packages is quite close:

Slic3r PE: Used filament 6.12 m = 18.26 gr in 2h 5min -- it took 2h 52 min in reality
Simplify3D: Used filament 4.50m = 13.52 gr in 1h 38min -- it took 1h 47 min in reality

I have always seen those numbers as a ball park and that is OK. That the printer needs one hour longer is baffling. The only thing I can think of that really makes a difference like this would be excessive retractions and/or z-hops. That is something I need to check tomorrow. Some of those settings are difficult to find and match.

Cheers.

Posted : 22/03/2019 12:44 am
vintagepc
(@vintagepc)
Noble Member


I did not think of that. Unfortunately our postal scale is just a non metric thing and both come out at 0.5 oz.

Interestingly enough the "guesstimation" of both software packages is quite close:

Slic3r PE: Used filament 6.12 m = 18.26 gr in 2h 5min -- it took 2h 52 min in reality
Simplify3D: Used filament 4.50m = 13.52 gr in 1h 38min -- it took 1h 47 min in reality

I have always seen those numbers as a ball park and that is OK. That the printer needs one hour longer is baffling. The only thing I can think of that really makes a difference like this would be excessive retractions and/or z-hops. That is something I need to check tomorrow. Some of those settings are difficult to find and match.

Cheers.

One is putting down ~1.5x the filament of the other, so it's not surprising it takes proportionally as long. Time to start looking at your print settings (perimiters, infill density, extrusion width, etc)

Posted : 22/03/2019 1:33 am
boris.k8
(@boris-k8)
Active Member


One is putting down ~1.5x the filament of the other, so it's not surprising it takes proportionally as long. Time to start looking at your print settings (perimiters, infill density, extrusion width, etc)

I never found that the values calculated by slicer software, regardless of who makes it were anywhere near the real values. It took Simplify3D several years and the latest version comes within 5% or so.

If that ~1.5x were correct one should also weigh more (much more) than the other. My scale shows the same value for both objects, thus there is something else going on.

I will figure it out, weekend just got started... 😉

Cheers.

Posted : 22/03/2019 2:07 pm
charles.p14
(@charles-p14)
New Member

Have you been able to figure it out?

Posted : 24/03/2019 7:42 am
GeorgeE
(@georgee)
Trusted Member



One is putting down ~1.5x the filament of the other, so it's not surprising it takes proportionally as long. Time to start looking at your print settings (perimiters, infill density, extrusion width, etc)

I never found that the values calculated by slicer software, regardless of who makes it were anywhere near the real values. It took Simplify3D several years and the latest version comes within 5% or so.

If that ~1.5x were correct one should also weigh more (much more) than the other. My scale shows the same value for both objects, thus there is something else going on.

I will figure it out, weekend just got started... 😉

Cheers.

Maybe your scales are not good enough to distinguish a difference in the weights. 0.5 Oz = approx 14.15g and the estimates are just below this and a little more above, thats assuming both slicers have the same density of filament set which they may not have. They both should know exactly how much length of filament they use so that is a better measure of filament used and there is a vast difference between the two. As recommended before, check the infill density (and pattern), number of perimeters, number of top and bottom layers, layer patterns etc to make sure both are set the same. As it stands it looks like simplify3d is using less filament than slic3r pe which explains your difference in speed.

Posted : 24/03/2019 11:30 am
boris.k8
(@boris-k8)
Active Member


Have you been able to figure it out?

I think this is due to certain default parameters are quite different between both software packages. For example in Slic3r the default extrusion width is .45, but in Simplify3D it is 0.40. Infill perimeter overlap in Slic3r 25% and in Simplify3D it's 10% and so it adds up. Infill pattern is different too.

Some settings are difficult to compare to each other, because the naming is quite different.

It would be unreasonable to get them to a 100% identical result though. I will periodically check on Slic3r PE and the progress they make, but will stick with Simplify3D for another reason. I print quite a few RC airplanes (3dLabPrint). Oddly enough their STL files are "compatible" with Cura and Simplify3D but not with Slic3r. I tried it anyway and sure enough those airfoils are useless. Slic3r ommits the inner structures - actually identifies them as invalid manifolds and throws those bits and pieces in the bin.


Maybe your scales are not good enough to distinguish a difference in the weights. 0.5 Oz = approx 14.15g and the estimates are just below this and a little more above, thats assuming both slicers have the same density of filament set which they may not have. They both should know exactly how much length of filament they use so that is a better measure of filament used and there is a vast difference between the two. As recommended before, check the infill density (and pattern), number of perimeters, number of top and bottom layers, layer patterns etc to make sure both are set the same. As it stands it looks like simplify3d is using less filament than slic3r pe which explains your difference in speed.

Yeah, the scale is rubbish. For some odd reason the majority over here thinks the metric system is something evil and needs to be avoided at all cost.

"They both should know exactly how much length of filament they use..." - believe me they don't. It's somewhat close at best.

The estimation must be based on flow rates. If you ever tried to write software and using measurement sensors to get accurate flow rates and the calculate from there - it's a nightmare. Been there, done that...it sounds easy, but it is a tall order, really.

Cheers.

Posted : 25/03/2019 4:12 am
Share:

Please Login or Register