Show all posts by user
Page 1 of 2
Pages: 12
Results 1 — 30 of 40
QuoteSound
We could probably do something right now, while we figure out the bigger picture.
An inset value (in mm) to apply to the outer loop (in addition to extrusion_width/2 which is already applied) An additional extrusion multiplier to apply to the outer loop (to allow user to reduce flow as Sublime proposes)
Hi, and thanks for taking time.
I am curious about how Slic3r knows if a perimet
by
Qsilver
-
Slic3r
Just a quick update...
I have been re-checking many things.
Found another interesting calibration error.
My Y axis belt was slightly uphill to the print bed from the end pullys. 5mm or so
Prusa v2... Never thought that having the belt just slightly out of line would cause a measurable error.
It does... .25mm per 100mm travel. Not huge but another source of error.
by
Qsilver
-
Slic3r
So I did some checking on my printer.
My extrusion parameter was off, and I was over extruding about 7%
I have since re-calibrated and now the extrude length is acurate to .05mm per 10mm or 0.5%.
I will be re-printing many tests.
I will let you know where this gets..
Rich
by
Qsilver
-
Slic3r
So here is the error with 5% over extrude, inner to outer perimeter order.
Here is a whopping error of .106 per side .212mm on a hole ID...
I think that this covers most of the possibilities..
I'm sure there could be contributing material issues also.
Mean time I will be re-checking my extruder calibration....
by
Qsilver
-
Slic3r
Here is the error with a 5% area increase... a miss calibrated extruder length of 10.5mm calibrated as 10mm.
Not out of the realm of possibility.
This would get to .146mm on a hole.....
by
Qsilver
-
Slic3r
Quotenophead
I am wondering if multiple outlines actually gives a bigger error because the plastic doesn't want to flow right into the sharp corner under the rounded edge of the previous line. If it leaves an air gap there then each subsequent outline will give an bigger error, which seems to be what I observe.
I agree with you.. If the order of perimeters is middle outer inner (3 perimeters) th
by
Qsilver
-
Slic3r
Quotenophead
Not sure why you think it should be making correct parts when you have shown the volume dispensed makes a track 0.4537 wide but only offsets by 0.4/2.
I guess I'm not saying that Slic3r is correct in it's assumptions, just that is not a software logic error.
Slic3r clearly sets the perimeters as .4 wide and extrudes the correct amount of plastic for the .4 x .25 ideal area.
The .4
by
Qsilver
-
Slic3r
Hello again..
I'm sure you are getting tired of these ramblings...
I used the e values to calculate extrusion area and plotted the 2 layers in this sketch...
Then I used sample values and calculated (spread sheet) the extrusion area for layer 1 and layer 2.
Look at that exactly the correct volume for layer 2..
WTF? The software looks like it should be making a part perfectly.....
For n
by
Qsilver
-
Slic3r
Moving on a bit...
I must conclude that Slic3r is placing the print head in the correct location if the first layer is printed with .550mm
And borders with .400 mm... Now my question is why are things not in the right place?
I guess I will have to look at the E parameter on this data set.....
More to come...
Richard
by
Qsilver
-
Slic3r
So I made a thicker part 3mm of the same so I could look at each layer...
STL is attached...
I then went into G code and split layer by layer...
Overall I am impressed with the nice job that the software is doing. Lot's and lot's of math...
Here is layer 3: Plot of print head to actual designed borders of part.. ( I tried to remove most of the rapids..)
Here is the slic3r comments section
by
Qsilver
-
Slic3r
Ok so I wrote an SolidWorks Macro to read so I could overlay the G-Code points.
Here is the result... This is the first layer.
The blue lines represent a .518 wide nominal rectangular extrusion.. See above.
The center opening is 12mm The inner G-Code circle is 12.550 dia...
by
Qsilver
-
Slic3r
Here is some G-Code...
As I understand the second line makes a move X from 100.404 to 101.047 and Y from 93.733 to 93.800.
Also matching linear the extruder from 1.03202 to 1.04310..
G1 X100.404 Y93.733 E1.03202
G1 X101.047 Y93.800 E1.04310
Accordingly this table suggests 0.1295 sq mm in the extrusion...............................................
3.100 mm^3/mm 7.54767635
by
Qsilver
-
Slic3r
I was looking at the physical sizes of things and created this image of a 3mm extruding 0.4mm at .5mm wide.
Thought it was interesting....
by
Qsilver
-
Slic3r
Ok, Since I started this thread, I have not gotten any answers..
More questions yes, but answer no...
I have created a couple more files for testing.
I am on my way to warm up printer and try soon.
The files and drawings are created with SolidWorks.
I will take a look at the G-Code that is output and see if I can make heads or tails....
Richard
by
Qsilver
-
Slic3r
Quotejustcurious
Quotetmorris9
And the tool path is off in slic3r so no settings will ever make holes the right size.
Is it possible that you can give us some documentation on this statement, which i believe untill otherwise proofed is your own experience.
Hi,
I am not trying to start any debates as to which slicer may or may not have problems..
If there is a software problem with Slic3r, I
by
Qsilver
-
Slic3r
Great results...Nice to see dimentional quality that exceeds my thinking.
Rich
by
Qsilver
-
Slic3r
QuoteSublime
.......Now my prints are always within 0.05mm of the target size and I now model all holes exactly the size I want them......
Did you try the attached STL file, doesn't take too long to print.
Rich
by
Qsilver
-
Slic3r
Quotewaitaki
I think the problem is with circles, not hex nut holes. .......
A 6 sided nut hole is easy for the extruder just as a square hole would be - it will move in "easier" straight lines so to speak but dragging the filament around a circle seems to cause it to pull towards the center, hence making it smaller.
If that is the case then why would large diameters be worse then small ones in
by
Qsilver
-
Slic3r
Quotejustcurious
well, I think you have by far too big ambitions about accuracy with 3d printers. Think about again.
You have a nozzle that can make a line that is 0,40 wide or larger, never smaller. .....
...
You can always try with the specific print to choose small changes of extrusion width and layerheights to find the optimum result for that print, but never expect that there is a standard f
by
Qsilver
-
Slic3r
Ok, so I made test part.
A drawing of the test part, and what I measured (Red - average), is attached.
Also the STL file is attached so you can print and see if you get similar results.
My set up is 0.40 nozzle, 0.25 layer height, ABS @ 230, bed at 110. Speeds default.
I measured with digital calipers.
The ID dimensions still are small.
Small holes @ 0.5mm and other locations 0.5 to 0.7
I
by
Qsilver
-
Slic3r
Seems like software this advanced shouldn't have an acuracy problem this large....
Is this a bug in the software that it cannot calculate the correct position?
Wonder if the extrusion thickness goes to the wrong side of the part... ?
That's about the error I seem to be getting.
by
Qsilver
-
Slic3r
I just had this today...
Try using the up down arrow next to the raft layers.
When I type 0, and save the modified, reverts to 1.
If you use the up arrow down arrow to make it a 0, then saves ok.
Richard
by
Qsilver
-
Slic3r
I hope someone here can help me.
I have attached a couple of images to explain.
My inside dimensions (like A in picture) are printing too small.
Outside dimensions (B & C) are all printing good.
What could be causing this?
Part designed in SolidWorks exported as STL...
Richard
by
Qsilver
-
Slic3r
My RepRap project summary.
I thought I would share my experience in building my Prusa Mendel 2
First, thanks to all who contribute to this forum. Without the discussions here I would have had more difficulty and not as good of a result.
The project began as a Christmas gift December 2013. Actually the purchase of components began nearly a year ago, leading up to Christmas having all compon
by
Qsilver
-
General
Starting building my Prusa V2..
I bought palin steel 8mm threaded rods.
Read a few places that the galvanized can gum, up in the Z's..
The plain steel with oil is filthy dirty.
Rich.
by
Qsilver
-
Cleveland Ohio - RepRap Usergroup
Yes these are the 3 carriers with ears for the bearings.
As for mounting, they are designed with a hole for a small zip tie to go around.
I have not bulit mine yet, so I am not 100% certian how I will attach.
I am using LM8UU ball bearings on harden 8mm ground rod.
I am not allowed to play with mine till X-mass..
Rich
by
Qsilver
-
General Mendel Topics
Ataching the heat bed is a little unclear.
Use clips but how many?
This is shown with 3 - 1" binder clips.
I am not sure
by
Qsilver
-
General Mendel Topics
Cool,
Thanks for all of the comments.
I am hopeing that I will be running by January.
Richard
by
Qsilver
-
RAMPS Electronics
Page 1 of 2
Pages: 12