3D Print Show London

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A rather nice venue

So today it was up bright and early and onto the train for a trip to the London 3D Print Show. I went last year and I enjoyed it so much I’ve gone back this year. There was a bigger venue and more stuff going on. Same mix of presentations, stands and exhibitions, but generally just more of it. The business is definitely maturing. The general thrust of things is towards are more “appliance” type devices which folks could just get hold and use to print things. There was also a stunning display of how 3D printing is being used in medicine, from printing tissue and prosthetics to making 3D mock-ups of the patient for the surgeon to practise on.

Ultimaker were there with the new Ultimaker 2 and a wall of Ultimaker 1 machines. There were lots of other brands there I’d not seen before.

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This printer was turning out pottery, which was very impressive.

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They even had people selling parts. That heated bed looked very tempting….

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There were 3D printed moustaches up for grabs.

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This stuff looks amazing. PLA fibre with wood particles in it.Makes prints that look like tiny carvings. I got a little sample of the stuff which will be very interesting to play with.

On the way out I went past the shop and bought a bunch of Faberdashery colours that look really nice. I’m going to have a go at printing with them tomorrow. But I might have a bit of a lie-in first.

Tiny Golden Owls

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I tend to buy all my 3D printing fibres from Faberdashery. They are by no means the cheapest, but I’ve found their quality and consistency to be very good, and they have a range of really nice colours that go well together, at least to my untrained artistic eye.

There is one little trick that the company plays that is really rather cunning. When they send you a box of fibres they always include a few metres of a colour you haven’t ordered, to play with. This is sneaky because it usually ends up with me ordering a full roll of that colour. Today I got some new fibre and found that they’d included some gold stuff. This is not just gold, it has tiny flecks in it that look really nice. The picture above doesn’t really do it justice,

I’ve never really managed to get a happy ending when I print very small objects, they just tend to merge into one molten looking lump. However, I thought I’d have a go because if things went badly at least I’d not waste much raw materials, which didn’t cost me any money anyway. So I printed out a couple of tiny owl earrings and I don’t think they’ve turned out half bad.

A 3D printing tip: One of the things that determines the quality of the print is the “layer height”. The printer prints by laying down successive layers of plastic on top of each other. In theory, the thinner each layer the higher the resolution of the printing. My printer is supposed to be running at high quality when it prints layers which are a tenth of a millimetre thick. However I’ve found that in practice an ultra-thin layer doesn’t work very well. The print head is so close to the object being printed that it melts one layer as it puts the next on top, resulting in a sludgy looking mess. I’ve had much better results printing with thicker layers. The owls above were printed using layers that were a fifth of a millimetre in height. You can see each layer, but I quite like that, in the same way as wood has a grain, I quite like to be able to see how the object was constructed. I reckon it is worth trying to print out at with thicker layers sometimes. The printing will be quicker and it might even look nicer.

Printing the Weather Forecast in 3D

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We had a good audience for the first Rather Useful Seminar. Some of them were fresh from a first year lecture and must have been feeling a mite peckish. But they stayed to the end and I hope they enjoyed it. The talk was very similar to the one I did last year, but there was a twist at the end, when I printed the weather forecast as a plastic object. Again, I brought along Una the Ultimaker, and again she behaved herself very well.

I’ve become quite intrigued with the idea of generating objects from software, and it occurred to me that with the FreeCad tool having a Python interpreter in it, we should be able to do something interesting. I’d no idea how to use Python to read a weather forecast but fortunately Catalin George Festila has done it here. So I took his methods which use the Yahoo weather feed and prints it out and made a few changes.

def weather_for_zip(zip_code):
    url = wurl % zip_code +'&u=c'
    dom = minidom.parse(urllib.urlopen(url))
    forecasts = []
    for node in dom.getElementsByTagNameNS(wser, 'forecast'):
        forecasts.append({
            'date': node.getAttribute('date'),
            'low': node.getAttribute('low'),
            'high': node.getAttribute('high'),
            'condition': node.getAttribute('text')
        })
    ycondition = dom.getElementsByTagNameNS(wser, 'condition')[0]
    return {
        'current_condition': ycondition.getAttribute('text'),
        'current_temp': ycondition.getAttribute('temp'),
        'forecasts': forecasts ,
        'title': dom.getElementsByTagName('title')[0].firstChild.data
    }

This is the code that he wrote that fetches the weather information from the Yahoo weather service and creates a list of objects that contain a forecast item for five days. The forecast information contains the highest temperature for each day, and that’s what I’m going to use to control the height of each of the columns that I print.

def main():
    a=weather_for_zip("UKXX0476")
    noOfReadings=5
    # find range of temperatures
    highest = float(a['forecasts'][0]['high'])
    lowest = highest
    for i in range(noOfReadings):
        v = float(a['forecasts'][i]['high'])
        if highest < v:
            highest = v
        if lowest > v:
            lowest = v
    # make some blocks 
    plinthThickness = 3.0  
    blockWidth=5.0
    blockDepth=5.0
    blockStartHeight = 5.0
    heightRange = 20.0
    rangeScale = heightRange / (highest - lowest)
    x=0.0
    y=0.0
    plinth = Part.makeBox(blockWidth*noOfReadings,blockDepth, \
        plinthThickness, Base.Vector(0,0,-plinthThickness))
    for i in range(noOfReadings):
        v = float(a['forecasts'][i]['high'])
        blockHeight = blockStartHeight + rangeScale * (v - lowest)
        block = Part.makeBox(blockWidth,blockDepth, \
            blockHeight, Base.Vector(x,y,0))
        plinth = plinth.fuse(block)
        x = x + blockWidth

    Part.show(plinth)
    Gui.SendMsgToActiveView("ViewFit")
    Gui.activeDocument().activeView().viewAxometric()

main()

The Yahoo zip code for Hull in the UK is UKXX0476. This code fetches the weather forecast data and then finds the largest and smallest temperature values (something which should be familiar to first year students). It then makes a row of five blocks, each of which has a height set by the temperature for that day. I’ve re-written it from the demonstrated code so that the coordinates make a bit more sense. The width and depth values map onto the x and y directions, with height being the z value. The code creates a little plinth and fuses a series of blocks onto the plinth. The length of each block is the temperature for that day.

forecast

 

This is the object that was produced by FreeCad. It represents the temperatures 12, 16,14, 17 and 16 degrees, which is the rather chilly forecast for the next few days. I sliced the design using Cura and then, after a bit of kerfuffle I managed to print out the temperature plot.

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The weather forecast. And a tiny owl.
I printed it out really tiny (all of the dimension values above are in mm) but I reckon it came out quite well. I’ve since found a flaw though, in that you can’t tell which way round it is supposed to be read. Of course I could add an arrow or emboss some text to make it easier to use.

I must admit that I can’t see a huge demand for physical manifestations of the weather forecast, but I hope it brought home to folks how easy it is to grab information and turn it into something tangible. There is a lot of scope for random patterns and generating objects from mathematical formulae. And, as you can see above, it is very easy to do. I made an offer that if anyone uses Python to make an interesting object I’d be quite happy to print it out for them.

You can find the slide deck here. At the end Peter was kind enough to show some videos of his printer in action. You can find out all about the “Richmond” 3D printer at his blog here.

3D Printing Fun at C4di

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Well, that was fun. Peter, David, Helen, Paul and myself all got together to talk about 3D printing and scanning at C4di. I took along Una, my Ultimaker printer, David, Helen and Paul took along their 3D scanner and MakerBot printer and Peter showed off his “Richmond” printer.

Within no time the place was full of the smell of hot plastic and the sound of machines whirring away. We had a huge audience (in that there were lots of people, not that they were giants) and they seemed to really enjoy finding out about 3D printing. I started things rolling, with a quick zoom through my presentation about how I got into making things and then Peter followed up with a talk about how he came to design and build his own 3D printer from scratch. As you do.

Finally David rounded off with a description of how 3D printing and scanning technology is being used in his business and how it will undoubtedly develop in the future. Helen and Paul were showing off their modelling and scanning skills and the whole thing ended with lots of happy people wandering round, taking a look at the technology and getting to grips with it. Without getting their hands burned.

Thanks to Jon Moss for setting up the session and C4di for hosting it.

Peter’s 3D Printer

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I went out this afternoon to take a look at Peter’s 3D printer. You can find out more about it here. I’ve actually seen it now. It’s awesome. The most impressive thing is that all the parts were designed by Peter and some of them were printed by me. And it works. To the point that the fan mount on the picture above was actually printed by the printer itself.

I made my printer from a kit and I’ve been slowly discovering the best way to get things from a roll of plastic fibre into a useful shape. The learning curve has been steep at times, but what Peter has done is much more tricky. He has had to construct and align all the components himself.

The design of the printer is totally unlike mine. The position of the printing head is controlled by the movement of the three carriages up and down the three pillars. The controlling software drives stepper motors that are connected to cable that is looped around each pillar and pulls the carriages up and down. The great thing about this design is that the head can move really fast, and during printing the item being printed doesn’t move at all. The tricky thing is that printing in straight lines involves all the motors making complex movement (which is not a huge problem, the software does all the tricky maths) but any inaccuracy in the movement will result in straight lines becoming curved or slanted.

Peter has spent a lot of time aligning everything and now he is getting some excellent results. Eventually he will be using his printer to make a whole new one.

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This is my favourite view of the printer.

3D Printing in Windows 8.1

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Now, I’m not particularly old. But I can remember when the very idea of having your own printer was the stuff of dreams. Printers were places you went to when you wanted to have something printed. And as for printing in colour, that was beyond dreaming.And then the first dot-matrix and daisy-wheel printers appeared, closely followed by laser printers and finally inkjets. And now everyone has a printer.

In the early days of printing, it was a bit of a nightmare. You had to have the right kind of printer, the right kind of software and the right kind of drivers to get anything sensible. And often the thing printed didn’t match the image on the screen, or was the wrong size or shape. Eventually things settled down. Standards were set and now you can buy a printer in the confidence that it will just plug in and work with your computer.

I reckon that 3D printing is following a similar trajectory. We are at the point where hardware is appearing and we need some standards so that it can be made available to the widest possible audience. My experience with the technology has left me thinking that a 3D printer is not yet an “appliance”, but that in the longer term the attractiveness of the technology means that pretty much everyone will want a device eventually.

That’s why I’m really pleased that Microsoft have announced support for 3D printing in Windows 8.1. This is really only a step on the road to widespread adoption, but it is a really good one.

Learn Things from Rob at TechEd EU

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I’m doing some sessions at TechEd 2013. If you want to know how to make your Windows Phone use background agents to add value to your application, or respond to what you say, then I’m your man. I’m speaking at 10:00 am on Thursday about speech and 3:15 about background agents. And I’m going to be around at Ask the Experts too.

I had this brilliant plan for TechED US, where I’d give away 3D printed phone cases at my session. I even printed them and everything. Then I found out that the phone that I’d printed the cases for is not actually sold in the US. Which makes me an idiot.

So, instead, this time I’m giving away “I learned something from Rob” ceremonial plaques. These are completely unique, except in the sense that there are more than one of them in existence. I’ll also be giving away lovely 3D printed red rockets. So come along to my session, answer a question and you might be in the running to win.

Above you can see the 3D design for the plaque.

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This is what the real thing looks like. With a bit of luck I might see you in Madrid, and give you one.

Problems in Pink

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That could have gone better…

Peter is still working on his 3D printer. Today I had a go at printing another part for him. It did not end well. As you can see above, when the printer runs out of fibre to print, bad things happen.

I’ve mostly reached the point where failed prints are not as interesting as they used to be, but even so I’m tempted to hang on to this one. The problem came because I’m coming to the end of my lovely pink/magenta fibre and the last few metres are tightly wound around the inside of the spool. When they are fed into the printer the tight curves of the fibre cause more friction in the tube that pushes them into the print head. This gets harder to push, so the knurled bolt that is doing the pushing starts to slip against the fibre, eventually wearing it in two.

Then you get to strip down the feeder and extract the broken bit. Fortunately the print head wasn’t blocked, and so I was able to switch to red fibre (that little coil that looks like red hose is me forcing out the pink and sending in the red) and print all the bits with no problems.

I’m going to have to make something that straightens the pink fibre out so that I can use it.

Useful 3D Printing Text

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Chris (the author the above) was kind enough to send me a copy to take a look at. You can download your own from Amazon for the princely sum of 2 pounds 22 pence. If you want to know what 3D printing is all about, how it works, and some ideas about how you could build a business based on 3D printing technology I reckon it is well worth a look.

This kind of text is perfect for electronic publishing as the field is very fast moving and I hope that Chris is able to keep it up to date. The writing style is conversational and the content is packed with little nuggets of information that must have taken quite a while to put together.

Addicted to 3D Printing

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You know you are an experienced 3D printer when:

  • Strangely shaped bits of coloured plastic from failed print jobs are no longer fascinating to you.
  • Your bedroom carpet is covered in strangely shaped bits of coloured plastic.
  • You can get hold of strands of plastic at 200 degrees centigrade and think "Ooops" rather than dancing round the room holding your hand and swearing.
  • Your hands acquire some funny looking scars and blisters as a result of this.
  • You start to make up tunes inspired by the noises your printer makes when it is working.
  • Whenever something works you instantly try to print out a bigger one. Or a smaller one. Or a red one.
  • You start to like the smell of molten plastic.
  • You feel that you are at the cutting edge of technology, even when your wife asks "What's that meant to be?"
  • You think a little plastic bust of yourself would make an ideal wedding present for someone.
  • You begin to plan your social life around eight hour print jobs.
  • You don't know what PLA stands for, but you know exactly the temperature it melts in your machine. In five different colours.
  • The word "plug" becomes a swear word.
  • People start giving you designs they’d like to have printed out.
  • You start to wonder if there might be a business model in this…..

Refining Una the Ultimaker

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I think you should know I endured a lot of pain to fit this part…

Just because I’m on holiday, doesn’t mean I don’t get to play with tech. I spent a big chunk of today fiddling with Una, my Ultimaker 3D printer. I don’t usually give my devices names, but since I’ve discovered that this particular device has moods I thought a name would be appropriate. The great thing for me about 3D printers is that they don’t work all the time and you can always persuade yourself that there are things you can do to make them better. Perfect for a tinkerer like me, who was brought up on Meccano.

Today I convinced myself that by replacing the wooden end bearing caps with adjustable plastic ones I could probably improve print quality. I could certainly cut down on the banging and crashing that I was getting during printing, when the print head changes direction and the rods it slides on are pushed into the side of the case. I’d already made one change earlier in the week, when I upgraded the fibre feed mechanism that pushes plastic into the machine. That had improved print quality a bit and so I figured I was on a roll with this.

So I set to and printed all the parts (finding a matching colour for the case, which was nice) and then I had to fit them. This was where the fun started. I put the original fittings on as I was constructing Una, and then put lots of parts around them. This meant that the nuts holding the end caps in place were really hard to get to. I tried printing out a “nut calumet”, which sounds like a desert from a posh restaurant, but is really something you can use to put the nut on the back of the bolt. But eventually I found the best way to replace the fittings was just to jam my finger inside the machine behind each nut, so that it held it in place, undo the existing bolt and put the new one straight back in. This removes the need to put the nut in place, as it never goes anywhere, and leaving aside the pain involved in forcing your finger inside very tight spaces, worked very well.

I’m not sure if the print quality is that much better to be honest, although printing is a lot quieter and smoother than it used to be. I’m a bit worried that steel bolts in the end caps are going to grind chunks out of the steel rods they are rubbing against, so I’ve ordered some brass bolts (which cost the princely sum of 14 pence each) to replace them with. These should form a bearing against the steel and be a bit smoother.

If you have an Ultimaker then I think it is a worthwhile upgrade, just because it makes printing much quieter. If you are about to build one from a kit, I’d advise getting some end caps printed so that you can put them on during construction and save yourself a bit of pain later.

Building a Door of Mystery

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After a considerable amount of tweakage of designs and waiting for the printer to finish I now have my “Door of Mystery” machine complete. This is how it looks inside. I’ve added a WiFi card so that the door can upload pictures after they have been taken.

After all my careful planning the box needed a bit of surgery because I’d forgotten that power connector protrudes from the front of the board, but apart from that (and having to go and get some more bolts) it is now pretty much complete.

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This is the finished device. I’m going to have to slightly adjust the hole for the RFID reader in the next version, but it is quite pleasingly solid and works a treat.

You buy an RFID tag to enter the competition, show it to the “Door of Mystery” above and it will give you your entry number and take your picture. Then, I can use my special “Pick a Winner” tag to pick a random entry and even view their picture. We might even use this for bashes, where we might want to give out random prizes, pick team members or let people take it in turns to use some of the games.

Just the Wrong Size

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So today I had a go at printing out my designs. Above you can see the result. And I’d made a mistake that I’ve made before. I made the holes exactly the same size as the things intended to fit into them.

Do. Not. Do. This.

Of course they don’t fit. One thing just sits on top of the other looking exactly the same. Wah. I did think I could solve the problem by filing a bit off. Not a win.Turns out that PLA is actually quite tough stuff. After about ten fruitless minutes and quite a bit of pain (who knew you could get splinters from plastic things) I gave up and went back to the software. The good news is that I just have to tweak a couple of values and rebuild everything. I’ve even added a feature where objects can cut holes in the entire finished piece, so that the SD card and the screen can cut slots for themselves.

Ongoing.

Making Boxes with Software

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This is the base design I came up with. You can also see one of the Gadgeteer part designs where it will be fitted in the finished product.

I’ve been designing a box for the “Door of Mystery” Gadgeteer device that I built for the Red Nose Day event. But I’m very lazy. I don’t want to have to lay out the various elements by hand and position them individually. I want this to happen automatically. So I’ve wanted to write a program to do this. Peter likes OpenSCAD, so I went there first.  OpenSCAD lets you create 3D images programmatically. It is really easy to use, and you can preview your designs very quickly.

module panel(width, height, x, y)
{
    translate([x,y,0])
    {
         cube(size=[width, height, baseDepth]);
    }
}

I used this tiny snippet of OpenSCAD to place a panel on the drawing surface. I move the axis to the position of the panel and then create a box of the required size. You can perform unions to merge things together and differences to cut one shape from another. In no time at all I was programmatically creating bases for the Gadgeteer devices. And then I hit a brick wall. What I really wanted to do was have the program work out where each device goes in relation to the other ones and lay out the box contents.To do that my program has to keep track of where things have been put. This means that I need some variables.

OpenSCAD does not provide variables as such. It provides constants (such as baseDepth above) but these are evaluated at compile time, and so I can’t use them to keep track of things as the program runs. This is not necessarily a criticism of OpenSCAD, it isn’t really meant to run programs, but it does mean I can’t use it.

So I went back to my old friend FreeCAD. I first used this ages ago, when I made the case for my Tweet Printer. FreeCAD can be controlled by Python programs and I’ve always fancied learning a bit of Python, so of I went. The designer has a Python console into which you can paste and run lumps of code. You can also add libraries and user interfaces on top, but I was happy to cut and paste for now. All the actions you take in the designer are exposed as Python calls via the console, which makes it quite easy to figure out how to do things. You just do it in the designer and then look at what comes out on the console. There is also an API reference which tells you how the commands work.

def makeBoard(self,x,y):
    b = Part.makeBox(self.width,self.height, 5, Base.Vector(x,y,0))
    return b

This method is a member of my “Filler” class which places the filler (which has a width and a height) at a particular place on the design. Note that the filler is 5mm thick in the above code. The program can take the object that is returned and fuse or cut it with other shapes as you build up the finished design. By the end of all my fiddling I’ve got a class hierarchy of Gadgeteer device specifications and a layout engine that will place them in a box of a particular size.

def MakeTop():
    doc=FreeCAD.newDocument()
    f1 = Filler("Filler", 5,25)
    f2 = Filler("Filler", 6.5,25)
    f3 = Filler("Filler", 6.5,20)
    rfid = RFIDReader("rfid", "landscape")
    camera = Camera("camera", "landscape")
    display = DisplayT35("display", "portrait")    
    topComponents = [rfid,f1,camera,f2,display,f3]
    test = Layout(91,121,topComponents)
    board = test.layout()
    Part.show(board)
    Gui.SendMsgToActiveView("ViewFit")
    Gui.activeDocument().activeView().viewAxometric()

The MakeTop method creates the top of the box which contains an RFID reader, a touch display and a camera. These are laid out in an area with a dimension of 91x121 mm. Each component can be either “landscape” or “portrait” orientation and you can create filler elements to push things around in their row. The design method is given a list of components and an output area. The finished design looks like this:

TopDesign

These elements cut extra holes for themselves so that they show through the front of the box. The layout method also creates the sides and puts fixing holes in them, so that I can join the top and the bottom together. If I want different size of panel thicknesses I just change the static members that control these values and run the method again. If I want to make a different design I just create a new method which contains the devices that want.

The system is not completely automatic, what I end up doing is fiddling with the output from the method and then changing the orientation and adding fillers until I get what I want. The good news though is that it provides a really quick way of making Gadgeteer boxes. I’m going to have a go at printing the designs later in the week.

I find it fascinating that I’m now writing programs where the output is a physical artefact. We do live in interesting times.

3D Printing on Sunday

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Peter is building a  3D printer.He fancies a Rostock configuration. He has been doing some design work using OpenScad. Today he brought some designs round and we had a go at printing them. Lessons learnt, rounded corners are hard work. The printer builds objects layer by layer and if the edges are curved it seemed to make it harder to just print the outer layers. Peter was able to rearrange the drawing really easily and we had a go at printing again. The output looks like it might prove the basis of a print head. The next thing to do is print some of the side struts and the carriages that go up and down the pillars.

Printing Lumia Cases

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My printed case, and Joanna. The cutout for the camera fits absolutely perfectly.

BrianT popped a comment on the blog last week about the Lumia printing templates that Nokia have just released. They can be used with a 3D printer to allow you to print your own shells for the Lumia 820 phone. You get designs for the shell plus the buttons. You can download them here. What with having a Nokia 820 and a 3D printer to play with I thought I’d had a go. Initial results weren’t successful because the back section is very slightly curved in the original Nokia designs, which for a 3D printer like mine is impossible to print (although other kinds of printers will do this kind of shape). However, a chap on Thingiverse has created a Makerbot version of the case with a flat bottom. This prints a treat, as you can see above. The only thing I don’t like is the Makerbot logo, what with me having an Ultimaker printer and all.  But I can fix that by spending a few minutes in FreeCAD. In fact I can put whatever I like on there. In any colour I like.

The shell snaps onto the phone just like a “proper” one and I was very surprised to find that even the tiny buttons fit well and work OK, although I’m going to have to do a bit of trimming to make them move smoothly.

Remember that the lack of a 3D printer doesn’t stop you from making your own unique phone cases. Places like Sculpteo will take your designs and print them, including full colour if you really want it. Kudos to Nokia for making these drawings available for anyone to use.

Printing LED Enclosures with Ultimaker

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Spent some time today doing some 3D printing with the Ultimaker. And by some time I mean quite a while.

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Nearly a six hour print, one of my longest so far

I’m making an enclosure for a set of Gadgeteer LED Matrix Modules from GHI. I want to combine four of them to make a 16x16 dot LED display. Once I’ve built it and got them working I’ll figure out what to do with them. I spent a while last week printing out version one of the enclosure. Rather stupidly, I made this exactly the right size, i.e. 120mm wide internally. I figured that since the units were 60mm in size each that would work fine. Not so. It made them just the right size to not fit. It is a testament to the Ultimaker printer that they would not fit either way because they were exactly the same size as the opening in the enclosure. Darn.

So it was out with FreeCad and away to design a new enclosure with an extra mm all round, so that I could actually get the units into it. I also added some support pillars that engage with the Gadgeteer boards behind each display. What I need now are some really slim nuts so that I can bolt the displays in place.

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This is the finished print, complete with “sprue” that I’ll have to clean off. It took me ages to prise it off the blue tape. I think I need to adjust the platform a bit to make the top layer a bit smoother although, for this build, you don’t actually see this bit.

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Here is the tray with the LED units fitted.

Successful 3D Printing

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I’ve been playing with my Ultimaker 3D printer for a while now and I’ve reached the point where it is almost, but not quite, an appliance. By that I mean that I can walk up to the printer with a desire to print something and produce what I want. Most of the time. Here are Rob’s top tips for printing.

Raw Materials

Get the latest software:  The best software for Ultimaker is Cura. It was specially written for the device and it works a treat. It is updated regularly and gets even better each time. The latest version, which starts a print off by “dive bombing” the print surface, works really, really well.

Use the right plastic: I only use stuff from the Ultimaker shop or Faberdashery. These places do a range of colours and I’ve found the consistency and quality of what they produce to be very high. The Ultimaker forums are full of people who have had problems with systems when they started to use some cheap stuff they got from an auction site or wherever. Once you get dodgy bits into your print head it is very hard to clean it out. There are two kinds of plastic you can use in your printer, PLA or ABS. I must admit I’m a confirmed PLA chap. This stuff melts at a lower temperature and I’ve found it much easier to work with. It sticks to the print bed really well and doesn’t shrink as much during printing, which reduces the amount of warping that you get.

The Ultimaker people recommend that you print something using the higher temperature ABS to “seal” the print head and block any holes with high melting point plastic so that if you perform later prints with PLA there will be no seepage. I tried this and what happened to me is that I managed to completely block the print head with some high melting point plastic which meant I had to use the “fit a new one” cleaning technique. The new print head design, which you must have, is not prone to leaks in my experience, as long as you make sure that you tighten the head up when it is hot.

Setting Up

Spend a while getting the height of the print bed just right: It is only important to get the print bed alignment right if you actually want to print anything. If you get the height wrong you will either see nothing printed (because the print head is pressed hard against the print bed and no plastic is coming out) or print balls of wool (because the print head is too far away and the stream of fibre just goes out into the air). One trick that worked for me was replacing the bolts and springs that support the print bed. I put in some much longer bolts and some springs that I stole from ball point pens. These give a much longer range of travel for the print bed and make the bed less likely to move. Then I used “Rob’s Patent Bed Levelling Technique”, which goes like this:

  1. Adjust the screws to make the print bed as low as possible.
  2. Move the print head into the middle of the printing area.
  3. Manually turn the Z axis screw until the print bed is a few millimetres away from the print head.
  4. Adjust the Z limit switch so that it triggers at this point. Test this by turning the Z screw by hand to make sure that it trigers. Do this before you use the software to send the print head home.
  5. If you have got this right you should have a situation where when you send the print head home it ends up a few mm above the print surface. Now you can level the bed off using the adjustment screws.
  6. The four screw positions for the adjustment bolts form a square. It is very important that you adjust the height of the print head on the lines of this square and nowhere else. Otherwise, when you adjust the height at one screw you will affect the height at another, which will drive you nuts. The idea is that if you get the height right on these lines it will be right for the entire surface, because your print surface is flat. 
  7. Adjust the bolts so that you can slide a single piece of paper between the print head and the print surface. Do the final adjustments when the print head is hot. I always do a sanity check before every print where I send the print head home and then slide my magic paper to make sure that the clearance is still OK. This ensures that if the bed has got pushed down while I was removing the previous piece from the surface I discover this and pop the bed back into place. Once you get the height right you will never have to adjust the bolts again.

Make sure that the plastic is flowing before a print: At the start of a print you can turn the print feed drive to push fibre out of the head. Do this. Make sure that you are getting a nice stream of plastic out of the head just before you print. As soon as the head is hot you should hand feed some plastic and then set the print going. Any hiccups in the plastic feed at the start of the print process will probably stop the first layer from sticking to the print bed, which will end badly. Some people use “retraction”, where the software pulls the fibre back during printing to remove spurious bits from the print and make it tidier. I’ve never used this, the idea of sucking hot plastic into a cold part of the print head just scares me. And I’ve been perfectly happy with the results of ordinary printing.

Printing

Keep an eye on the print process: My experience has been that if I leave the machine for too long, bad things happen. And anyway, it’s fun to watch.

Make sure the fibre is feeding well: I’ve had a few situations where the roll of material on the back of the printer has “gummed up”, stopping the feed of plastic into the printer. Make sure there is plenty of slack. Actually, I now don’t use the roll on the back at all. Lots of fibre is supplied loose, and so I just lay it on the floor underneath the desk where the printer is standing and then just turn the roll round as the fibre is used. I did experiment with a turntable that would feed fibre from a roll laid on top of it, but that didn’t work very well so now I manually rotate the roll every quarter of an hour or so. This means that I have a reason to keep an eye on the printer, which is nice.

Après Print

Never leave the print head hot: If the head is hot, it should be printing. When I started using the printer I thought that giving the printer a few minutes to properly warm up would make printing better. It really, really does not. What happens instead is that the heat travels up the print fibre which melts and then solidifies when you start printing, forming a plug which takes ages to fix.

Release the Fibre Feed when you leave the printer: I’ve no idea whether this solves a problem or not, but it works for me. Whenever I know I’m leaving the printer for a while (more than a day or so) I release the fibre drive at the back of the printer. My theory is that taking the tension off the drive bolt and associated parts will make them last longer. I’ve no idea if this works or not, but I’ve not had any problems feeding fibre into the machine, and I want to to stay that way.

Keep the print head clean: This is particularly important if you change the colour of your prints a lot. I have a “sacrificial rag” that I use to wipe down the print nozzle just after a print, when it is still hot. This stops a print from picking up stray bits of plastic of a different colour. Do this carefully, so you don’t burn your hands.

Enjoy your Printer

Look for things to print: I bought the printer as a way of making cases for gadgets. I’ve done that, but I’ve also had a lot of fun finding things on thingiverse and just printing them. Especially the rocket.

Try different colours: Faberdashery do lots of colours, and even luminous fibre. They also do a “variety pack” of different colours which is great fun.

Show it off: The printer is quite portable, I use a big blue Ikea bag to carry it around. I’ve not found that it loses calibration when it is moved, which is nice.

Luminous Rockets and the Lumia 920

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Now, this one impressed me lots. What you can see above is a picture of a rocket that I printed using “glow in the dark” fibre from Faberdashery. I took the picture using my Lumia 920 in pretty much pitch darkness. You can just see the edge of another, non-luminous, rocket on the left of the glowing one.

The picture was taken hand held and I’ve done nothing more to it than a slight crop. Amazing.