Printing on the diagonal

[KenL 0]

I have a Crealty CR-10 printer. I designed a large rectangular part the was 11.75" x 3" x1". When I loaded the .rsdoc file into Cura (3.2.1) and tried to slice, it said there were no parts that would fit the printer. It should have fit since I can print 12x12x13. So I rotated the part 45 deg. on the plate and it sliced. I printed the piece only to find out the hole spacing (inside the part) was correct, but the part had shrunk in length.

I tried to load the .rsdoc file again, got the same result, centered the part (as before), noted the length, and then rotated 45 deg. After the rotation, I checked the length and it had been reduced.

 

Is this a software issue, because a friend has a different slicer when done using his SW, the result prints the part horizontally, not requiring it to be printed on the diagonal.

[DidierKlein 729]

Hi and welcome,

 

Maybe check the units. If you work in inches, cura works in metrics so millimeters, so when you import an STL (i assume you add an STL and not RSDOC), it will think the scale is in mm not inches so it might scale automatically (or not)

[KenL 0]

Hi DK,

 

Thanks for your response. I design using Design Spark Mechanical. I do design in inches, but when I export the design as an .stl, it is translated into mm for Cura. The actual long dimension (in Cura) was 297.6 mm (which was approx. 11.7 inches from my design). Cura would not slice my part. So, I centered it on the plate and rotated it 45 deg. The length changed to 228.4 mm. I then checked to see if scaling was changed and the menu said everything (with the new dimensions) was 100%. Cura does not seem to recognize my printer as capable of printing 12x12 and when trying to fit it on the diagonal, does auto scaling---which doesn't make sense as to why it would do that--the part is not that wide.

[gr5 2,172]

When working in cura it works with any shaped part.  It doesn't know that your part is a rectangle - it is meant to work with an infinite possiblity of shapes.  When it is telling you the X, Y, Z distances of your part it is telling you how much space the part takes up in the X axis, Y axis, and Z axis.  It doesn't tell you how long your part is.

 

So when you rotate a long thin part that was previously very short in the Y axis, the Y axis value will increase as it should.

 

This scaling feature that shows distances is not very useful after you've rotated a part other than 90 degrees.

[gr5 2,172]

After rotating you can go into the scale feature and set the scale to 1,1,1 (unity scale - no scaling).  It could be that the brim or some other thing in cura is causing the part to not quite fit the CR-10 bed.  To get full use of the bed

 

set "travel avoid distance" to zero.
disable brim and skirt both!

There's something else to do...

 

details here:
https://ultimaker.com/en/resources/44677-maximum-build-volume-ultimaker-2-plus-ultimaker-3
 

[KenL 0]

Hi gr5.

 

Thank you. I will try these settings. And I '''think''' I understand your explanation of why re-sizing is happening. What is confusing in the display is that all 3 part dimensions are shown, and as I rotate my rectangular solid, I thought only the X dim was changing. But, now that I check again, I see both X & Y change. So again, thanks and I will try your suggested settings and report.

Edited March 1, 2018 by KenL

[KenL 0]

It turns out that I had not removed the skirt. Once done, the part fit. However it still doesn't seem right that if I had a part that was 13 x 3 x 2 that I could not print it. It would certainly fit on the diagonal. My friend has the same volume limits as mine but uses a different slicer (however, not free) and prints on the diagonal when needed to fit.

 

Is there no way to disable the 'auto scaling' function in Cura when you rotate a part in the XY-plane??

[gr5 2,172]

I'm pretty sure you can disable auto scaling.  Go to "preferences" and "configure cura" and in the general settings there is (I think) what you want.  I'm not going to tell you which one because there are only about 10 and it's good for you to know the other options in there for future purposes.

[KenL 0]

gr thank you,

 

I did as suggested and there is no setting to disable that 'feature'. I will keep asking and looking .At this time, not necessary, but may need it in the future.

[kmanstudios 1,120]

I do not know what you mean by 'AutoScaling Function'. I have to print on the diagonal all the time to make things fit and nothing ever gets scaled unless I scale it. It remains at the size it was before such rotations/

[KenL 0]

kman,

If you check my previous posts, that is not the case. I described a simple rectangle that was slightly longer than 12". As I rotated the part to 45 deg. I could see the dimensions changing. I missed this the 1st couple of times, printed the part and sure enough it was shorter than designed. Maybe you have found the "magic" setting. This problem of auto-scaling was discussed in this forum for earlier versions of Cura, stated that it was corrected in subsequent versions and found to not be the case. I have not found anything regarding this issue on the current version---except mine.

[kmanstudios 1,120]

2 hours ago, KenL said:

kman,

If you check my previous posts, that is not the case. I described a simple rectangle that was slightly longer than 12". As I rotated the part to 45 deg. I could see the dimensions changing. I missed this the 1st couple of times, printed the part and sure enough it was shorter than designed. Maybe you have found the "magic" setting. This problem of auto-scaling was discussed in this forum for earlier versions of Cura, stated that it was corrected in subsequent versions and found to not be the case. I have not found anything regarding this issue on the current version---except mine.

And again, I have never seen this. You failed to answer the question about autoscaling as I have never seen it. Where are you getting this scaling differential? What is your feedback that this is happening? A before and after print? numerical scale info changing at rotation?

 

Telling me to read what I already read is not really helping. May be hard to believe, but there was legitimacy in the point of view opposite of yours.

[Brulti 177]

@KenL The only autoscaling that exists in the latest version of CURA (3.2.1 at this moment) is for autoscaling very small or very large part, ie stuff that is either in mm or meters, since one would be very hard to select and the other would just fill up the viewer and zooming out might not be possible.

 

If those are not checked, then CURA does not do any autoscaling. I've printed plenty of stuff on the diagonal on my UM3E and never have I experienced what you experienced.

 

Based on what you said, I believe you are being tricked by a quirk of CURA that @gr5 tried to explain in his first response: the measurement in the 'Scale' menu are not the measurements of your item, but a measurement of the volume it will occupy on the printing space. CURA is measuring the space that the printed item will occupy using predefinite and absolute X, Y and Z direction that do not vary.

 

For example, if I try to print a wrench horizontally then diagonaly, the measurements by CURA changes, but not the size of my item:

 

 

 

It only changes because I have changed the orientation. Cura measures using it's own reference system, irrespective of the orientation of your item, as shown by the big blue, red and green boxes. Thus, of course, if I change the orientation of my item, then the measurements in CURA changes since it doesn't care about orientation, it just measures in a straight line.

 

Basically,CURA makes measures this way:

 

 

And not this way:

 

 

Hope it helps you.

 

[kmanstudios 1,120]

14 minutes ago, Brulti said:

the measurement in the 'Scale' menu are not the measurements of your item, but a measurement of the volume it will occupy on the printing space.

If this is what the OP is referring to, then you are correct, it is the resulting bounding box of the object(s) to be printed and not a local measurement. All things in Cura are in Cura world space.

[Brulti 177]

4 minutes ago, kmanstudios said:

All things in Cura are in Cura world space.

 

 CURA dimension has it's own rules! *Cue scary music* 

[KenL 0]

Gentlemen,

 

Thanks to all of you for your input. I now understand why the dimensions changed on Cura as I rotated the part. The only thing I can't understand is why a couple of parts I printed on the diagonal came out smaller and were scaled down. It may have been an issue in my design and what got exported from Design Spark as an .stl. Again thank you all, and lately I have not been experiencing any similar issues with large parts printed on the diagonal.