Getting started in Cura and Tree Supports

[TheJimReaper 0]

Hi guys,

I've been printing for a year or 2 now, but have only ever used S3D for slicing as I found it easier to use and up until now it has served me well. HOWEVER, after purchasing this model https://cults3d.com/en/3d-model/art/bearded-dragon-articulated-toy-print-in-place-body-snap-fit-head-cute-flexi from Cults, I've found that the supports in S3D aren't giving me a particularly nice finish, so I thought it was time I started to use other slicers, which is why I'm here.

I've downloaded Cura 5.1 and I'm trying to set it up and configure it for my printer, this is where I ran into my first problem!

The Creality CR-10 Smart Pro isn't on the 'Add a Printer' list! So I assume I should be ok with just selecting the closest to it, this being the CR-10s Pro?

The next thing I want to ask about is using Tree supports. I think these will give me a much better finish than the supports in S3D will. Do I stick with the default settings or adjust them for distance between part, number of branches, etc?

Any help and advice would be greatly appreciated 

Thanks in advance

Jim

[GregValiant 1,322]

Yes, select a CR-10.  After installing the printer you can make changes to the bed size or whatever.  Cura doesn't care about the WIFI part and all CR-10s are functionally pretty much the same.  You can go to Manage Printers / Machine Settings and see the parameters and make changes there.

 

As for the tree supports, you are going to have to play with them.  There are 70 or 75 settings in the Support section.  Typical Z gap on top of supports is 1 layer height.  If you have supports that rest on the model then the floor height can be 2 layer heights.  Don't expect a perfect finish.  Tree supports grow differently but often the deciding factor is the Z gap and the density of the support interface.

[TheJimReaper 0]

Thanks GregValiant, much appreciated. I have gone through the millions of settings and sliced my first model, it looks ok on the preview. Fingers crossed it comes out ok. 

The times have got me a little confussed though. From what I can see I've got the same printing speed settings as I would use in S3D, but it has doubled the printing time for the model.  I know with S3D you have to add a little extra time on as it under estimates the print time for the model. 

Is Cura more accurate on it's print times or is it over estimating print times?

Thanks again

Jim

[GregValiant 1,322]

The accuracy of the print time is often dependent on the Accel settings and to a lesser degree the Jerk settings.  I don't know S3D but you can get the Cura times to better reflect reality by being honest with Cura regarding the settings.

You can tell Cura to use an Accel of 3000mm/sec² but within the printer (unless you changed it) Creality usually has a 500mm/sec² limit.  So the Cura estimate can be based on faulty input.  That's a big hit right there.  

After slicing - just above the "Save to Disc" button is a circle with an "!" in it.  Hover the mouse over it and you will get a synopsis of where the time is spent.

Another thing that can have an effect on small features is "Minimum Layer Time".  The layer needs time to cool before the next one goes down and so Cura will drop the print speed to maintain the minimum time.

Cura 5.1 has a new setting called "Flow Equalization Ratio" that is there to deal with the variable line width.  It smooths out the speed between a line that goes down at your maximum line width versus a line that might go down at minimum line width.  You can set it to "0" to take it out of play.  Prints can be a tad better using it at higher numbers.

Overall I've found that for my Ender 3 Pro Cura over-estimates by around 10%.  I did kick up the Accel and Jerk limits using M201 (accel) and M205 (Jerk).

There was one poster here who was using 7mm of retract but his E speed was only 1mm/sec.  That's 14 seconds for each retract and prime.  That was really bad.