Space Geodes at Ota Fine Arts Singapore (4 August 2018 – 15 September 2018)

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The show at Ota Fine Arts is all set up, with many thanks to Jodi for inviting me to show the work. I’ve shown this work two times but this is the first time I had the option of REAL PLINTHS. I previously used all acrylic casings as plinths. At the time it was a practical decision as I was using whatever unwanted ‘plinth’-like items I could find and The Substation was getting rid of these old casings – but also it was a consistent material to the rest of the work. Plastic upon more plastic!

[PS you can read more of my writing about the work here as well:]
Space Geodes: On the 3D Printed prototype as Digital Fossil
Space Geodes at Singaplural 2016
Public Service Notice about Geodes

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Left: Space Geodes at Singaplural 2016. Right: Space Geodes at Objectifs in 2017.
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Space Geodes at Ota Fine Arts in 2018
Given free choice over the colour that I would want the plinth to be, I’d always choose Grey as a neutral base over White or Black. We chuckled over the names given to the colours and I have to admit I was almost tempted to choose a colour simply because it was named “GRANITE ROCK” or “SLATE GRAY”. (Ultimately if the names given to the colours by savvy paint companies were totally ignored, the choice would have been very clear to me anyway; it was always going to be a specific warm mid-range sort of grey for which I don’t have a name but can always pick out of a lineup)

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I did give the arrangement more thought this time around. Recently I’ve been enjoying laser cutting a lot because I now have access to a lasercutter in the NYP Makerspace which is literally a 5 minute walk from where I am staying at the moment (and its under-utilised!) so as a simple experiment I tried to make an acrylic base/riser which would also light the work from beneath.

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Geode with base

The only reason I haven’t gone with this lighting option is the fact that there is a little colour discrepancy in the “white” when it is lit. My lights and acrylics are too “laser white”, whereas the work glows with a warm white. Weirdly enough, some of the works looked more yellow when lit, as if they differed in thickness, which I couldn’t understand to be the case since they were designed as hollow shells of the same thickness for the SLS process (to save on material cost)

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The answer as to why there was a discrepancy in thickness and lighting became clearer later. As I was arranging the works yesterday, POWDER STARTED COMING OUT OF SOME OF THE WORKS. The powder had been thicker in some portions so that was why the lighting was not consistent. Having shown the works two times before, I was surprised that powder was draining out now when I’d have expected any excess powder to come out of the work in the previous round. Perhaps it was all the transportation and vigorous moving about that dislodged the excess powder hiding inside the print, for the white nylon powder began issuing forth from the escape holes I had designed for the works.

Perhaps on previous viewings we had treated the works so very softly and cautiously as if we were handling live explosives – but this time around I put them in a basket for rocks and slung them over my shoulder as I carried them to the gallery.

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For those unfamiliar with the Selective Laser Sintering (SLS) process, it is an additive manufacturing process in which the laser sinters the powder into a solid material, but because the material itself is quite costly, designers often design the part as a hollow part with some escape holes so the excess powder can be shaken out. I would have thought that all the powder from before had been shaken out by now!

Its a bit funny as come to think of it the white powder flowing out visually resembles a weathering process in which the rocks break down into smaller particles. Earlier in the day I was also just building a prototype for a new work in which one can see material flowing in a similar way. When something breaks down into particles that small, the dust is literally blown into the wind. There’s no “trying to collect it in a cup and sticking it back together”. Its just gone, blown away, it ceases to be an identifiable part of the thing it was once part of.

Prototype for a new work
The private view for the group show is tonight – please come down to see if it you’re in town!

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The exhibition will be on view from August 4 through September 15, 2018 at Ota Fine Arts, 7 Lock Road, #02-13 Gillman Barracks, Singapore 108935.


SPACES
Kray Chen | Sheryl Chua | Debbie Ding | Hilmi Johandi | Tristan Lim | Ian Tee
4 August – 15 September 2018

Opening Reception in the presence of the artists:
Friday, 3 Aug 2018, 6.30 – 8.30 pm

Ota Fine Arts Singapore is delighted to present SPACES, a group exhibition featuring 6 artists from Singapore: Kray Chen, Sheryl Chua, Debbie Ding, Hilmi Johandi, Tristan Lim and Ian Tee. This exhibition showcases each artist’s reaction to the spaces and structures in contemporary society, as well as a more formal focus on pictorial space. From painting to photography, video, 3D print and textile work, diverse expressions by the artists discuss relations between the virtual/imaginary and actual spaces.

Lessons in 3D Printing: Raft Vs Brim Vs Skirt

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Designing and teaching a 3D module has had the unintended effect of giving myself the role of “de facto 3D printing technician” and “general-all-round-fixer of 3D models and print settings”. Ah! I am a fool, for I had already known of the fickle nature of 3D printers, their unwillingness to behave when ordered to. Also the machine is a wilfully obtuse device that will do exactly what the designer asked it to do even if the designer has made an awful mistake.

Here is a list of lessons I have learnt after facilitating several hundred hours of 3D Printing in a mini workshop. Printers used were Raise3D N2.

1. Raft Vs Brim Vs Skirt? JUST USE A RAFT

What is the difference between using a Raft, Brim and Skirt?

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The Raft is an additional piece below the entire print itself.

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The Brim is an extension of the first layer which expands the amount of contact the first layer has with the print bed. The print’s first layer is already touching the bed itself, unlike the raft which is an additional few layers below the print itself.

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The Skirt is just an additional line printed around the print itself.

Often one may think that the raft is a waste of material but I have found that rafts are absolutely essential since it will affect the first layer adhesion greatly, and with this kind of FDM printers the first layer adhesion is one of the main factors which will literally make or break your entire print. As the raft is much bigger than the print’s footprint (and also bigger and thicker than a brim), it ensures better adhesion to the print bed.

Also if you end up having difficulty in removing the print, you can afford to damage the raft somewhat during the process of removal – without also damaging the actual print.

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Example of failed print: This generally flat print would not complete when I printed it with just a skirt. It would only print when I did it with a raft. For a large print, this kind of error may cause the print to turn into a huge blob that can potentially be pushed into the axis belt – breaking it and causing total breakdown of the machine. So you can imagine how these problems with adhesion shouldn’t be taken lightly if you want to keep on printing!

2. Infill Density
10% will do for non-load bearing parts all the time. Don’t bother printing more infill unless needed.

3. Always Check Slicing Preview
Check Slicing Preview for EVERY PRINT before printing. More often than not it will provide the clues for whether a print will actually complete. A common issue is where the work is not touching the print bed. If there is a gap in a layer, or no raft over any part, or any part which defies gravity and the known laws of physics, then do not proceed for THIS WILL NOT PRINT WELL. Redesign the part before printing.

4. Tricks for very large overnight prints
Lay item as flat as possible on the print bed
Ensure that you have observed the raft completing successfully before leaving the print to run overnight.
If you don’t want to do a raft because a raft would exceed the print bed size, set the first layer to be extra thin.

5. Only Cura can slice right-extruder-only print for dual extruder printer
A crazy question you may find yourself asking if you are using a dual extruder is “should I try to use just the right extruder to print?” Well, no, its not advisable at all, and also I can’t seem to find any other slicing app which allows for such a setting. Alternatively, you can dive into the gcode directly and change all instances of T0 to T1. However the problem remains that right-extruder-only prints may experience nozzle strike:

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Left: Nozzle Strike in progress. Right: Print which I stopped because the left extruder was clearly impacting on the print being produced with the right extruder only.

FFF/FDM (Fused Deposit Modelling) vs SLA (Stereolithography)

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I spent the last few months producing over 100 prototypes for an exhibition which is showing at NUS Museum at this moment (It was also the work I showed at my graduation show at RCA). In practical terms, this meant that I pretty much sat next to the 3D printer the entire time tuning it. The conclusion? I NEVER EVER WANT TO RUN A RAPIDFORM SHOP THAT PRINTS THINGS FOR OTHER PEOPLE. Whatever the advertisements tell you about the miraculous magical instant dream of 3D printing – ITS A LIE. There are still many material limitations.

I have also thought very seriously about selling off the UM2 (FDM printer) to get the Form 1+ (SLA printer), but have come to the conclusion that it is not worth it. Here are some of my thoughts on both types of machines:

FFF/FDM PRINTER

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FDM stands for Fused Deposit Modelling but technically Stratasys owns the term FDM, so an alternative term for it (if you care about the legal semantics) is also FFF or Fused Filament Fabrication. The reason for so many cheap FFF machines is that the patent has expired on this technology so many cheap and DIY version of FFF machines have been developed.

Imagine a tiny jet extruding tiny blobs of plastic which solidify into a larger solid – which makes your object. Its that simple. I’ve been using the Ultimaker 2 so far, as it has had some of the best reviews. Although the UM2 technically can do up to 150mm/s, 50mm/s is usually the top speed that I can go if I want really high quality and no risk of unexpected under-extrusion. Most times if I see a “difficult” portion coming I might even tune the speed down slowly.

Printing notes:

1. Slowing down the first layer helps: If a print lifts off the heated bed on the first layer with a newly calibrated bed, I sometimes stop the printer and force the printer to start the first layer at a face-slappingly slow 15-20mm/s. This actually seems to make all prints work better in general. If the print is not well stuck on the first layer, the whole print may be problematic.

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Fused Deposit Spaghetti Machine – first layer failed to stick to bed

2. Level the print bed: You can mislevel the bed such that if you are doing 4 prints on the same bed at each corner of the bed, then just one or two of them will be less “stuck” to the bed. So levelling the bed is important. At times, it just seems impossible to do right!…

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Three were fine but one had a terrible and stringy brim

3. Don’t print multiple prints too close to each other: If you print multiple objects on the same bed at the same time, sometimes the heat from the nearby prints can cause general warping or for parts of the “foot” of a print to curl up from the bed. I try to print objects one after another, not all at once, it seems to work better.

4. Increasing the temperature by 5-10 degrees can help – but only for a while: Raising the temperature slightly can help some prints along at times. But if you set the temperature too high for too long, it will burn the filament (it will turn brown in parts) and cause a filament jam.

5. Get some good lubricant: You’re supposed to oil the machine once in a while. I ended up buying Ballistol which is suitable for use as a gun parts lubricant. I’VE TRIED MY BEST, IS THAT STILL NOT ENOUGH FOR YOU, MACHINE?

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6. Check for random problems: Finally, I had a period where all my prints weren’t working for a few days and it turned out that the colorfabb roll has a design which makes it snag on the especially long M3 screw I had sticking out of a new material feed that I had installed. AARGHHH! There was no choice as my local hardware shop only sells M3 bolts in a few fixed dimensions and that was the only one I could use. There was no way to stop it from accidentally snagging, and I couldn’t find replacement bolts immediately, so I eliminated the filament spool entirely and unrolled it out. Actually, after this I managed to print without A SINGLE FILAMENT JAM for a few solid weeks. MIRACLE!!!

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Who cares if this looks like crap on the table if it works

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Countless ways to do it wrong
Basically FDM printers can seem frustratingly temperamental because they won’t tell you exactly what is wrong with them, so you have to figure out what went wrong. Most of the time the under-extrusion problem can be due to filament jam (mechanical issues), temperature problem, speed problem, etc.

SLA PRINTER

In Stereolithography, laser shoots through a photo-reactive resin/polymer bath and solidifies parts of the liquid into a solid, then the print emerges from the liquid bath like terminator.

The main reason why I never got an SLA printer in the first place was because the 3D Printer was going to live in a home environment. But since George and I moved to a big new house in March I thought for one brief moment of madness that maybe, maybe, I could allocate some space to a Form 1. But the problem is that I still cannot justify having a machine with such toxicity to humans and environment, as the prints would require curing treatment, which can also affect the size of the print (possible shrinkage/curling). And although SLA prints would have the potential to have thinner walls and higher detail without as much overhang problems, the type of materials and colours in which I could print with would be much more limited.

My assessment is that as a user I mainly want:
– large range of colours
– large range of cheap materials
– a dry work room (no “dirty” sinks)
– not having to potentially contaminate my living/working space with fumes

So FFF/FDM wins over SLA.

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Maybe I will just have to embrace the UGLY OVERHANG aesthetic…

I also don’t know how our pet snails feel about having the 3D printer next to their tank. There is no precedent for this even – I can’t simply google for “Are snails disturbed or traumatised by stepper motor sounds? Or do snails enjoy the vibrations from 3D printers?”. Anyway, more on our friendly domestic slimeballs in the next few overdue updates of this page…

OpenSCAD: transformations, minkowski sum, and lithophanes

This week I’ve been teaching myself how to use OpenSCAD, a free software which allows one to create 3D CAD models through programming. The syntax is really simple, logical, and surprisingly quick to experiment with – although if you would imagine there is an aesthetic trade-off between producing something super quick to model, render, and print – by default the simple primitives are of a low-poly quality, because this will suffice for most people producing functional household fixes. I find it interesting that by default the aesthetic of most objects printed from OpenSCAD will then automatically have the ‘computer aided design’ look.

To understand what I mean, here is an example of the same sphere with different overrides. There are actually special variables which can be bumped down to improve the quality = which control the number of facets used to generate all the arcs:

$fa – minimum angle for fragment (min value is 0.01)
$fs – minimum size of a fragment (min value is 0.01)
$fn – number of facets (this overrides the other two when present)

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Two other functions for rounding off things are hull() (which effectively gloops things together) and minkowski() (which does a Minkowski sum of two point sets.

Hull produces a convex hull of the objects you put together. Think of it as filling all the concave valleys between objects with a big flat hard-edged squeegee and polyfill.

Minkowski sum is touted as an ‘elegant’ way of producing rounded corners, if you apparently overlap objects together such as a cylinder and a cube, but its more complex than just that. The Minkowski sum as I understand it can be used to produce the solid sweep of an object in motion. It can also be used to calculate the set of all the possible positions of an object moving within a space. So in terms of it being used in motion planning, if there is an object which needs to find its way around obstacles in a space, the possible space in which an object can move is the minkowski sum of the obstacles + the object itself at origin rotated 180 deg.

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It is indeed a funny, fast way of getting a rounded edge but also potentially CPU intensive as I discovered I needed to drop the number of facets in order to have it process at a reasonable speed. If you use a sphere like in the 3rd example here and change $fn to 30 it may take over 2 hours to compile. So obviously for prototyping you would want to lower the number of facets so you can compile it faster along the way.

Basics transformations:
resize([x, y, z]) { … };
rotate([x, y, z]) { … };
translate([x, y, z]) { … }
mirror( [x, y, z] ) { … }
minkowski() { … }
hull() { … }


 

Using OpenSCAD to model functional household mods

OpenSCAD is perfect for producing simple household fixes in CAD. Here is an example of a Vileda mop head clothes pole adaptor which I made to hoist up clothing to a curtain rail. I used a vernier caliper to measure the pole and produced a few iterations to find the precise fit/size; the final print is meant to “snap” into place into the Vileda pole.

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(1) i realised i shouldn’t have printed it on a raft, it does not need to be printed with any support/brim/raft really; (2) i made the prongs too small; (3) prongs are the right size now, but in an attempt to make it fit better, i reduced the bottom by 0.5mm but that was too much…

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On Thingiverse: Vileda Mop Adaptor – Clothes pole
Functional household mod – ACHIEVEMENT UNLOCKED?


 


Lithophanes

I wanted to understand what might be a good way to produce a lithophane or in OpenSCAD. There was a function “surface” which could use a heightmap (image in dat format). Not surprisingly this is already well-trodden territory but I didn’t want to just use the thingiverse customiser to produce it without understanding it first, so here is my understanding of how it can be produced in OpenSCAD (following the method used in iamwil’s embossanova library)

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  • Started with a fetching image of George which I made into a PNG
  • Install Xcode
  • Install homebrew
  • Install Imagemagick (in terminal > brew install imagemagick)
  • Use Imagemagick to convert your image to raw grayscale (eg: in terminal > convert george_gray.png -type Grayscale -negate -depth 8 gray:george_gray.raw)
  • Use ruby to convert your raw file into a dat file (i used iamwil’s raw2dat example)

 

# raw2dat.rb from http://blog.cubehero.com/2013/11/25/emboss-and-impress-images-onto-a-surface-in-openscad/
width = 300 # => width of resized raw image
str = File.binread('george_gray.raw')
pixels = str.unpack("C*")

File.open(‘george_gray.dat’, ‘w’) do |f|
pixels.each_with_index do |pixel, idx|
f.write(pixel)
if ((idx + 1) % width) == 0
f.write(“n”)
else
f.write(” “)
end
end
f.write(“n”)
end

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Every pixel in this image is then turned into a number representing the pixel’s grayscale colour. So for an image of 100×100, there will be 100 numbers in each row, and 100 rows. It therefore forms a sort of terrain or heightmap that we can use in OpenSCAD.

mirror([0,1.0]){
scale([1, 1, 1/100]) 
surface(file = "george_gray.dat", center = true, invert = true, convexity = 5);
}

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In summary… this seems like an interesting or easy way to generate 3d printed terrains. I imagine you could put in a terrain or topo map for some place and print a 3d terrain out of it. The only problem is that we don’t recognise terrain, so some of its visual impact is lost; whilst George’s face is recognisable from afar and interesting to use (human faces in particular), a naturalistic terrain map is not going to be recognisable or understood in the same way. I’d imagine the only fun part in printing a 3d terrain would be the punctum of confronting someone with a 3d printed model and screaming at them THIS IS THE SURFACE OF THE MOON, NOW IMAGINE YOURSELF AS AN INCONSEQUENTIALLY TINY 0.01MM DUST MITE LIVING ON THIS SLICE OF THE MOON!

PS: the above lithophane of George’s face obviously has too many facets and will take a bazillion boring years to render. So please posterise the faces of your loved ones before turning them into lithophanes.

Meshmixer Experiment

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Began with a simple head model on thingiverse and then experimented with Meshmixer’s primitive sculpy tools for one pomodoro. This is basically like the iPad application – fun for a while but wildly inaccurate. The white line in the first image is the line of symmetry when “drawing”; your “drawing” will be mirrored on both sides. I found that it was better to add bits and small lumps one at a time (a bit like how one would model in wax with small fingertip-sized lumps to be slowly worked in) and finally just using BubbleSmooth to go over the lumpy bits.

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Sent it to print at a speed of 80mm/s. On hindsight this was too fast. Would set the print speed lower to around 40mm/s or 50mm/s for a small print like this in future…

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Support structure didn’t stick well to build plate. Nevertheless I didn’t cancel print since I realised it would probably still complete the print. Do note a bit of “elephant’s foot” on the first layer as well.

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Completed Georgehead. Overhang was quite messy due to part of support structure detaching from build plate quite early on in the print. Nevertheless I think it benefitted from the support structure. Might use a different slicer next time around to see if the support structure is done better for the same model.

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For comparison with the real Georgehead…


See also:
Georgehead on Thingiverse
My previous attempt at making a Georgehead in modelling wax at a Facial Reconstruction Class

Ultimaker 2: Printing a New Material Feeder

The point of a 3D printer or 3D replicating device is that it should be able to print new parts for itself; and this week in our house we were getting one step closer to the Singularity!

So I got the UM2 about two weeks ago, but I had some incredibly frustrating problems with the material feeder grinding filaments down terribly, exacerbated by my inability to open the screws on the material feeder itself. Fortunately, George’s bike allen key worked better than the UM provided allen key so he finally opened it and could clean out the ground up PLA and adjust the tension slightly. George thought my loosening of the screws of the material feeder (the 4 on the exterior of the black plastic case) could also have made the tension higher because of the design of the material feeder. Since the design of the material feeder was clearly the weak point in all this (nozzle was fine; already tried the Atomic method), we decided the next step should be to print a new material feeder for the UM2!

Turning temperature down midway too quickly ruins prints

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There was a weird blob of filament on the UM2’s nozzle which seemed to overhang dangerously so I thought I would slowly raise the temperature to 260 deg to get rid of it. After the nozzle had heated sufficiently to make the blob disappear, I turned the heat down to go to 220, but the fans were too effective and actually lowered the temperature to 205, and the sudden change in temperature caused some underextrusion, like scars on tree rings on these tiny teacup tests. Therefore if you need to change the temperature, it seems you should change it very slowly and no more than 5 deg at a time.

Improvised tools for retrieval of bowden clip which has fallen into hot end

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Removing the blue bowden clip takes some effort… and then some. Earlier yesterday, while the machine was turned off, I was trying to remove the bowden clip and it jettisoned itself out violently… RIGHT INSIDE THE HOT END. After having a small nervous breakdown, I was eventually forced to face reality and to improvise some new tools to retrieve the blue bowden clip from inside the hot end. These finally worked for us – a bamboo stick with blu-tack on one end, and a small paperclip fashioned into a hook. Use the stick with a sticky end to lift the blue clip and then fish it out with the hook.

This unfortunate error happened twice in the day.

Printing a new material feeder

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We tried to print all 5 parts of a replacement material feeder in one print with an initial layer of 0.3mm. The result was that every first layer was borked, although we didn’t understand what was the reason for it not sticking properly to the build plate. Obviously, if the first layer does not turn out right then the outlook for the piece seems pretty dismal. We tried this about 6 times and each print’s first layer either did not come out straight or detached from the print bed, so we aborted each attempt in succession.

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I tried putting some glue on the test bed (with a damp paper towel to spread it out), but I believe the glue doesn’t do very much and can be dispensed with, especially with a clean heated bed. After which we decided to print one part at a time with an initial layer of 0.2mm (and a lower print speed of 35mm/s) and it printed perfectly.

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Some appearance of “pillowing” occurs during printing process. Just saying, in case if you are paralysed by inertia and standing there watching the print like a paranoid babysitter – yes, the outcome will be alright as long the top layer is thick enough.

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After successfully printing two parts individually on its own, we decided to print 3 of the parts together with an initial layer of 0.2mm. This printed beautifully. Therefore one possible conclusion is that our initial problem with the smaller details of the print not properly sticking to the build plate might have been caused by setting the initial layer at 0.3mm?

settings

Update: EVERYTHING WORKS BEAUTIFULLY NOW. I recommend that if you have grinding problems with the UM2 that you print this feeder with similar print settings. Your sanity will thank you.


See also:
Atomic Method for fixing underextrusion problems
Ultimaker Visual Troubleshooting Guide by 3dverkstan

I’ve been bogged down by too much work lately (a constant and paralysing problem), and regrettably am behind in a lot of documentation and writing. But during the course of my projects involving any 3D printing, each weekend I’ll do a sum-up of all my prints and experiences with the UM2.

Ultimaker 2: The Importance of Filament Guide design, and Underextrusion Troubleshooting

This week I bought an Ultimaker 2 so I could start work on a new project in which I intend to do a fair bit of prototyping and printing with different materials. I want to understand how a 3D printer works instead of handing my file over to someone to make the print for me – the same way a printmaker learns the intricacies of the printmaking process. In my mind, I thought it would be like just having a printer which poops out 3D models. But that was wrong. This is more like having a baby which is lovely when the baby is being lovely, but then you find that it does not have the ability to tell you what is wrong with it, and all you can see is that sometimes stuff might be coming out of it in rather unexpected ways. Horrifying ways. Oh and the sounds! The sounds which might be delightfully high-tech if you’re in a good mood, or monstrous if you’re in an irritable mood.

Now, if someone were to ask me, “Should I get a 3D printer?”, my answer would be “Do you like fixing 3D printers? DO YOU??? DO YOU LIKE STRUGGLING WITH ALLEN KEYS AND PILERS FOR HOURS?” Let’s just face it – it appears that maintenance and fixing is going to be a big part of having a 3D printer. I feel like a person who has stupidly moved into the top floor of an apartment block without a lift. “Why yes, I don’t mind living on the top floor penthouse with no lift access, I don’t mind getting a little more exercise every day or having to hauling up my boxes up and down all these painfully endless flights of stairs!”

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The first prints were all fine. I thought it was quite noisy though but we took it back to the iMakr engineers to check and they said it was normal. Perhaps this is down to my furniture all being quite hollow. I think we can live with the noise, which is like a whirring melon of sorts. When it returned from the engineers, the first print I did after that had some underextrusion, causing one of my prints to snap into half when I was removing it from the build plate.

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Again, I’m no engineer, so it has been taking considerable time for me to really understand each part of the printer and fix what seem like minor issues… which then turn into many frustrated hours poking and tinkering with the machine. For example, I thought I had a nozzle problem but found out it was the filament feeder that was the issue and grinding the filament too tightly at the feeder.

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Knurled wheel had begun to grind the filament…
After some confusion of whether I should try to adjust the tension or to change the temperature or speed, I determined that it might just be a physical blockage and that I had to remove the bowden tube to manually pull out the jammed filament with pliers. The logic behind not upping the speed is that if you have an existing blockage, sending more material down the pipe at a faster rate doesn’t necessarily help the jam. I ended up having to go through the assembly manual and trawling the forums, wishing I had some calipers now to measure if my filament was INDEED 2.85mm as claimed or thicker in some parts and causing the jam, and falling into depression and demoralisation when I couldn’t exert enough strength to pull the jammed filament out of the Bowden tube (George had to help me with this).

filamentguides
From left to right: “Yet Another Ultimaker 2 Feeder” by sfriedri on YouImagine (combination of |Robert| and Geeks’s Design), Ian Spring’s Ultimaker 2 Feeder, |Robert|’s Ultimaker 2 Feeder with filament guide.
From looking around at different people’s modified feeder systems and from playing with the Bowden tube, I’ve determined that the issue is that the filament could benefit from some straightening before entering the bowden tube. Furthermore, if the spring tension was easier to change without the tiny finicky allen key, this would be an improvement.

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After fixing the jam I switched to white PLA and printing has resumed just fine and I made lots of tiny dollhouse cups as a quick test.

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One might say that with a 3D printer you would never have to buy as many things again since you could print it in the convenience of your own home. But convenience? Oh yes, just give me a few hours while I print this spoon instead of going outside to a shop to buy one in a heartbeat. It is a slow and hard process of getting to know the machine bit by bit along the way. Well this week I became acquainted with the filament feeder. All I can say is that I was amazed that I managed to fix it all at the end without making anything explode.

LESSONS LEARNT THIS WEEK WITH THE UM2
UNDEREXTRUSION TROUBLESHOOTING:

– Underextrusion – could be either a nozzle jam or filament jam. To confirm if it is a filament jam, check whether the filament can be removed or reversed. If the filament cannot be removed then its a filament jam
– If its a nozzle jam, which might happen if switching between PLA and ABS (which melt at different temperatures), you can clear it using the Atomic method.
– If its a filament jam, remove the jammed filament from the feeder and Bowden tube. Remove Bowden tube by first removing tiny blue horseshoes and pressing down on the white tighteners while pulling bowden tubes out. Do this for both ends. Then remove the misbehaving filament from the tube with a pair of pliers and replace them all back. If warping or deformation of the Bowden tube has occurred (which seems likelier to happen on the feeder end), trim a bit off but with a very flat and straight razor cut across.

3Doodler: Drawing Hinges and Moving Parts with a 3D extrusion pen

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I got a 3Doodler last year but only brought it back with me from Singapore to London recently, as I had backed the Kickstarter long before I actually knew for a fact that I would move to London. I backed it for 85 USD, which is around £50/SGD106, and came with a few packs of ABS filament.

There seems to be dearth of serious, detailed posts on the use of the 3Doodlers – besides the endless pictures of deformed Eiffel tower sketches and squiggly bicycles and lopsided glasses being posted all over the internet. My experience with it was that it was very hard to control and a lot of my initial output looked very sketchy and generally very crap; it will take practice to get better results. Get ready to generate an unholy amount of terrible, useless solid squiggles. And if you were expecting to print something specific with angular and sharp detail, well, this is more like a very specialised glue gun which dispenses a 1mm line of ABS, so it seems to me that this messy, “sketchy” or amateur look to its output is almost unavoidable for most users.

After three weeks of using it fairly intensively, I’m finally getting the hang of the control of the tool, learning how to draw in the air, make consistently straight lines, make decent likeness of objects, and I’ve also figured out how to draw moving parts.

Simple Models

All the following models are actually hollow on the inside. While drawing them I pretended I was a very imprecise 3D printer and did it in layers. And because they are hollow, they are lighter and use up less filament.

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Rabbit model

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Rabbit model 2

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Dinosaur Model (with four feet)

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Impressionist Merlion Model

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Octopus Model

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Ball (bouncy)

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Geometric Half Sphere (half-heartedly)

Models with Moving Parts

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Improved Glasses

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Improved Glasses (able to fold up)

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Detail of Hinge

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Windmill

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Windmill (in action – it even works smoothly when you blow at it!)

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Detail of Spindle

Here are some more of my notes on 3Doodler use:

Loading plastic: You really have to jam it in when feeding it a new filament for the first time, until it “catches”. The first time I loaded the plastic in, it seemed there was something yellow jammed inside it. I pushed and pushed very hard whilst pressing the slow extrusion button until the blockage came out. Basically you might find that you would need to push pretty hard to get it loaded; I was worried I was pushing too hard but yes that’s the way it is.

Speed of extrusion: There are two extrusion speed options, one is “fast” (bottom button, closer to nib) and one is “slow” (top button). I find the “fast” speed too fast and only use the “slow” speed.

Removing plastic: Press both the “fast” and “slow” extrusion button to make the filament go in reverse so you can remove it.

Colour Bleed of plastic: A major issue I noticed is that the previous colour filament may bleed into the new colour filament if the former is a stronger colour than the latter. If your nib has a bit of melted filament on it, if you accidentally touch the nib on something else you might transfer that melted colour onto your other work, or even melt a little “dirty coloured” dent into your other work.

Drawing: As they recommend in their user guides, you should use a piece of paper as your base for drawing. This piece of paper will likely be destroyed, but its essential to give your drawing some starting point which does not move. The ABS will peel off easily when cool – sometimes almost too easily, so be careful while drawing.

When finishing a line, just stop pressing the button and stop moving the 3Doodler and hold it there until it all hardens. When it has (a few seconds later) you can just gently but sharply tug away from the line to detach the 3Doodler from the line that was drawn. If you move immediately after letting go out the extrusion button, this may cause a messy thin strand of residual melted ABS to continue to spool out.

For flat designs, you can draw an outline on paper and then outline it with the 3Doodler – just don’t use pencil as it will transfer to the ABS. When doing this, take care NOT to press too hard into the paper if not you will be squeezing the nib into the extruded material, forming a small rivulet, gouged out in the centre of the line of extruded filament. There is a specific distance (which you will discover) at which you should hold the 3Doodler so that its extrusion comes out uninhibited but also straight/well-controlled so it doesn’t go crazy and suddenly spool a big uncontrolled squiggle into your work. Sometimes when I extrude for too long in one go or try to drag out the filament more, I get small airbubbles in my extrusion.

For drawing circles, hold the 3Doodler upright when extruding it. Avoid holding the nib at an angle which will increase the likelihood of the circle suddenly collapsing or gathering up on itself, especially with ABS which is easily removed from the paper.

For straight lines in the air, make sure at least one end is grounded on a paper or a fixed point. Allow some quantity of ABS to extrude, and then quickly pull the resultant strand completely straight and hold it there until it hardens. If you don’t want straight lines, you can nudge the extrusion gently for a moment or two after it has been extruded and you can guide it into a shape before it totally hardens.

Recycling Material: ABS (Acrylonitrile butadiene styrene) and PLA (Polylactic acid) are both technically possible to recycle. PLA is a bioplastic derived from corn starch so it technically can biodegrade very very slowly, although it would need to be sent to an industrial composting facility for that to happen on an appreciable level.

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