Neosanding - Automatic Layer Sanding

[neotko 1,417]

Difficulty level High

Warning, this isn't a easy trick if you don't know every aspect of S3D. And I mean, 'every'.

Hi guys,!

First, the images...

Basic Elements to make this Trick & have cool toplayers (sometimes perfect)

- Create a process that REprints only at the height of the last toplayer

- Adjust the settings so it doesn't extrude, and it things that his nozzle it's 0.25 size (play with this from 0.25 to 0.35). This trick will make that the nozzle (0.4 for this example) will do MORE passes on the same places, making it a better and smoother sanding.

- Adjust the speed of this new process so it's done really fast. Best results so far where at 100mm/s, I had some weird events at 150mm/s and at 70mm/s the speed it's too low and might affect the finish.

- You must remove top/bottom layers, set the process to 100% infill and play with the infill angle.

- Infill angle of the process MUST occur on the oposite angle of the real print top layer angle.

- Extrusion rate of the sanding process must be 0 or 0.02 (it's the less amount s3d allows)

What will happen?

It will 'sand' the top layer with the nozzle, removing the lines of the extrusion, making the print look much more 'natural' and (ONLY TESTED ON PLA) on PLA it gives a matte (or gloss if you play with the temp/speed & other things...) finish.

If you don't know S3D from A to B this will sound like an alien language

DOWNLOAD at youmagine my Example in FFF S3D (Factory file with the cube test) Neosanding ready to see how works.

https://www.youmagine.com/designs/neosanding-better-toplayers-finish

WARNING - The starting/ending Gcode it's the one I use on my machines, IT WILL 100% make the hotend crush with the bedclips, YOU must change it to your machine. If you didn't read this, sorry it's your problem. Also filament size, settings of the normal process, all, it's customized to my UMO+ with 1.75mm, FatIRobertI Bondtech, UM2+ hotend with custom fans. So EVERY setting will need to be readjusted.

Disclaimer: I share this so users with basic know-how can understand the concept, I take ZERO responsibility if you didn't read this before using the FFF on your printer.

Ok...

The first thing to learn to do this trick it's this...

Process ORDER DO matter.

So...

If you have a process (normal print) and the top layer gcode renders 'after' the toplayer sanding effect, then you need to a) Copy/Paste the process (this will make the copied process to pop on 'last' position. b) remove the copied process. Use this method to realign the process up/down as needed. It's the only way to make S3D does the effect just when you want it, and that's just after printing the real top-layer.

Edit: Just found out a faster, and easier way to force S3D to do the sanding process after the real print process.

If the real print it's done at 0.2000 layer height, then make the Sanding process have 0.2001 layer height.

Photos of the basic stuff to have a good control of

See that the sanding process it's before the print, this it's unintended. It doesn't need to be group, but weirdly enough it did work. Sometimes Process order won't look this neat, but 99% of the time the sanding process must be just before the real print process. Why? No idea.

As you see extrusion it's set to 0.02, extrusion width 0.25 to make more 'sanding' and retractions are off but for big dripping systems (aka 2.85mm or high temp) it might be good to use retracts.

The angle of the top layer done by the sanding process, since it has no 'top layer' or 'bottom' it's done by changing the angle of the infill. Remember the object must has 100% infill and NO toplayer or BOTTOM. Old S3D 2.0 did allow to change the top/bottom angle, but 3.x doesn't, so this it's the way to trick it.

Since it has no perimeters, you need to increase the outline overlap to at least 60-70%. 99% does work, but might leave marks on the perimeters. If you use 'perimeters' to make cleaner edges, remember to lower this to 40 or so, it's good that it goes beyond the normal area, but not too much. Play with this, each model might need readjustments.

Most and most important. On your sanding process you must choose where it happens. Otherwise it will the full object... and.. well, that works too btw, but it will make your print sooo slow and will create gabs of underextrusion on some places

Cura?

I think to do this on Cura it might need a lot of tricks, you can't make each top layer for each process, and if you mix this and plugins you might just go crazy. I hope @nallath like this and he or other guys make a Toplayer Sanding Plugin to replicate this hack. It works, and works everytime, but it has a few issues that need to be controlled.

- It might cause under-extrusion when it goes back to print. I found that the first perimeter printer after doing this effect had a slightly bit less material, no biggie, didn't affect the print.

- On high dripping materials this might not work or create mixed results. I did this for PLA since it's the material I use 99% of the time. I don't think that this will be a good idea for materials like wood (easy to scratch)

- On very easy to scratch materials, like carbon, wood, etc, YOU might need a Prime tower object to reload the material that did drip.

- The temperature of the nozzle while it's doing this will affect the finish. I did some crazy experiments before this playing with z, making the nozzle cooldown, etc. It was ok, but also a bit dangerous because the print could get knockoff, and ofc sometimes the amount of material on the nozzle was too much.

- Playing with the Z offset of the sanding process you can actually 'compress' the material, did some crazy tests with this with semitransparent red from colorfabb and was quite cool, but again, that's up to your experimentation.

It doesn't work for me, how do I do this!!??

Sorry this it's a really advanced hack with process, isn't something to click-print, and need's a good understanding of how process work and settings, and grouped things share settings, etc...

Have fun with process!!

Edited September 19, 2016 by Guest

[bob-hepple 59]

Really Like the Concept might get around to trying it when time allows.

[frederiekpascal 193]

That's an amazing quality of toplayer, thumbs up!

A lot of work to get it done though

[neotko 1,417]

Yeah, the truth it's that's easier than how it sounds (if you know how to use s3d). Just make a new process, change settings and select start/ending. But ofc it needs a lot of previous knowhow to knownwhat to do. Right now I have 3-4 profiles for each object I use (for keyhains, letters, etc) and once you have that it's very click print.

The hard part it's to really know how to use s3d, but there are good tutorial videos out there for that

[tinkergnome 926]

I admire your ingenuity...

That's genius!

...and can you please change the title of the topic to "Neosanding"?

Thanks!

[neotko 1,417]

I admire your ingenuity...

That's genius!

...and can you please change the title of the topic to "Neosanding"?

Thanks!

 

Lol XD ok! Thanks!!!!

[rigs 735]

AMAZING ! Perfect !

[ultiarjan 1,223]

I've got this feeling that neosanding will become a 3dprinting clasic !!! <3

[darkdvd 974]

CURA dev, please add "neosanding" in "Special Modes" section NOW !

[catohagen 41]

insanely cool idea, this should definitely be added to Cura as an advanced feature if possible

S3S needs competition

Im also hoping to see adaptive layerheights someday in slicers.

This have been done in cnc machining software for years, where you dont type in z step amount for contour milling, you type in max allowed step and software adapts cuts to what angle its milling. (imagine printing a 50mm ball, in the middle where the diameter is bigger a 0.2 layerheight is fine, but at the top it will look coarse and ugly)

[nallath 1,118]

If you want this done without all the weird ass manual steps, I don't think you can do this with a post processing plugin. I've sent this topic to some other engineers at UM so they can have a look at it as well.

[neotko 1,417]

Indeed a plugin where you select the layer, angle, repetitions, extrusion, line width, speed and z offset (for future stuff) should work just fine. And if it could have his own prime tower even better.

A prime/wipe would be really nice. It could 'sand over it' to clean the nozzle before sanding, then do the sanding & then go back to the prime/wipe tower to extrude and get the flow ready back to print.

Edited September 19, 2016 by Guest

[darkdvd 974]

"Sanding" can be a top pattern ?

[neotko 1,417]

Well IMO the sanding works nice with just infill angle, perimeters do work, but because the 100mm/s speed, sometimes it leaves weird marks from the speed yerk, and if you go below 70mm/s you can get weird effects on weak spots (because of reheating the pla just printed). It could be nice to leave that open, to allow perimeters, or only infill and selectable (or automagical) sanding angle.

[catohagen 41]

Just finished this in Colorfabb Ngen, settings might not be correct for Ngen but I adjusted atleast  temperatures to match how I print Ngen.

Surface difference is clearly visible, neosanding is more even and matte surface

[neotko 1,417]

Just found out a faster, and easier way to force S3D to do the sanding process after the real print process.

If the real print it's done at 0.2000 layer height, then make the Sanding process have 0.2001 layer height.

This way you don't need to copy/pste the process until you get the right order.

[avogra 68]

About speed jerk: Could you make the sanding area larger, so that the jerk happens outside of your part?

[geert_2 557]

I like this idea. It is remarkably simple (from a slicer point of view: redo the top layer with different settings and direction), but it is remarkably effective. Definitely worth developing further.

[neotko 1,417]

About speed jerk: Could you make the sanding area larger, so that the jerk happens outside of your part?

 

Indeed, the side effect is that without a prime tower, the small bits of filament left to be extruded make some small marks (they don't leave the hotend unless there's a hole to fall into). So to avoid this the only way I see it's to increase the difficulty (and print time) making a prime tower (that should have gaps), making the sand over the prime tower to clean the parts left of filament, and then moving to sanding with a fully clean nozze. Then ofc it will need to prime the extrusion before continuing.

[DidierKlein 729]

@neotko you are amazing ! I would never have thought of something like this!

The results are really cool on the images you posted, and i love the name

To avoid the prime tower to clean the nozzle there could be some kind of wiper thing (@foerstrum) where you would clean it with a special gcode just before neosanding

[neotko 1,417]

Yeah that would be perfect indeed, most of the time the first perimeter printed just after gets a slight underextrusion, fans help to contain the stuff on the nozzle, as soon you drop the fans the print can be a mess with weird effects. I think for weak fans it might be problematic.

[foehnsturm 969]

@DidierKlein, @foerstrum won't work, try foehnsturm

I already made some test prints using the 2nd head for sanding. But it will require some more. I'm still a beginner here (it took me 5 prints to realize that, as neosanding needs something to sand, it doesn't work well with toplayers with almost invisible but existing underextrusion)

[neotko 1,417]

Yeah I should have mention that I suppose. It took me a great deal of time to calibrate my esteps perfectly and until I used the ruby nozzle from Anders I wasn't able to 'see' the underextrusion ratio and fine tune it. Also it did help to solve the hard part of my prints that's the small letters. It was quite a ride. (that noone did seem to read or comment XD) the adventure it's on this post

https://ultimaker.com/en/community/19330-esteps-and-ultimaker-o-and-the-magic-missing-10?page=last

If you can't see the underextrusion and only use the effect for top layers, you can do this (it works, but with big flat areas you might get the nozzle with residue so I didn't publish it)

On the gcode of the sanding process change the offset so it forces the sanding effect to occur -0.02 Z (the minimum resolution of the z stepper), this will flatten the print, it also can add weird effects and drop down objects if they are too thin or not well stick to bed.

Edited September 20, 2016 by Guest

[DidierKlein 729]

@DidierKlein, @foerstrum won't work, try foehnsturm

I already made some test prints using the 2nd head for sanding. But it will require some more. I'm still a beginner here (it took me 5 prints to realize that, as neosanding needs something to sand, it doesn't work well with toplayers with almost invisible but existing underextrusion)

 

Oops i wasn't sure of the spelling and was too lazy to search for your name sorry about that

But somehow you still got the message

[ivan-lipunov 15]

Thats looks sexy as hell! Do you plan make some video tutoruals on YouTube about printing with S3D on UM2/UM2+? Or recommend good channels for learning?

Edited October 17, 2016 by Guest