Makertober Day 28: Printing Boxes

Some people say that you shouldn’t use your 3D printer to make boxes for things. I disagree. Sure, a box is quite large and takes ages to print. But its not as if you have to spend that time yourself. Once you’ve set the printer off you can leave it to get on with it. Although I do still find the process fascinating to watch. Above you can see the output of my design which I think is fairly tidy. I could spend some time fiddling with settings to get the print better, but this is not actually something that the user will see.

The reverse side, which is where the print was built up on my glass bed, is nicely shiny.

Makertober Day 26: Making heat tests

Now that I have something to print, the next thing I need is a working 3D printer. Oh well. Back into the fray. One of the factors that has a huge impact on the print quality you are going to get is the temperature of the print. So I’ve printed a bunch of tiny boxes to discover the optimal temperature. You can see the results above. It turns out that for optimal results with my printer I have to print at 215 degrees with a bed temperature or 60. If this sounds a bit high, you need to remember that the temperature is just the reading taken by the sensor in the head; not the actual temperature that the filament is being heated to.

In my print head the temperature sensor is right next to the heater which I think leads to higher readings. Anyhoo, from an engineering perspective any temperature that works is a good one.

Maketober Day 25: Making a light box

After a whole bunch of posts that have shown some creative uses of the word “make” but not actually described making anything, today I’ve actually made something. I’ve also done some time travel, going back to a program that I wrote quite a few years ago when I was designing boxes to put things in. I wanted to give the program a list of components and then have it turn out a box box for them. It worked especially well with the Microsoft Gadgeteer devices which were brilliant, wonderful and way ahead of their time.

def PirSensorBoxWemosWithPixelRing():
    print("Making PIR Sensor Box")
    proc = WEMOS("Wemos",verticalAlignment=VerticalAlignment.TOP, 
           horizontalAlignment=HorizontalAlignment.LEFT,xMargin=0.5, yMargin=0.5)
    holder = Device("blank", "blank", PixelRing.boardHeight, PixelRing.boardWidth,grid=[[proc]])
    lid1 = PIRSensorLidHole("PIRSensorLidHole")
    lid2 = PixelRingLightPipeLid("PixelRingLid")
    case = Case(wall_thickness=3,base_side_height=20,base_thickness=3.0,lid_side_height=5)
    case.makeParts([[holder]],[[lid1,lid2]])
    holeHeight=13
    holePos = Base.Vector((case.width-holeHeight)/2.0,case.height-1,-3.0)
    hole = Part.makeBox(holeHeight,4,8,holePos)
    case.baseDesign = case.baseDesign.cut(hole)
    case.show()

My box making system is written in Python and runs inside the FreeCAD tool. You can create component objects and then the system put them into boxes for you. The program works on pre-built software objects and has the ability to put components inside components. Above you can see the Python that makes a box that contains a PIR sensor, a 12 pixel neopixel ring and an ESP8266. The idea is that the will come on when you walk past the light. And, because the ESP8266 can do WiFi and other connected stuff I can make other lights come on too.

This is the output of the function. The ESP8266 is placed on the base of the box and the pixel ring and PIR sensor are fitted on the top. All I have to do now is print the boxes….

Makertober Day 18: Making a working printer

I think you should all know that the little plastic rocket above was the product of a lot of effort today. In the end I discovered that last time I mended the printer I’d left a tiny gap between two parts of the path into the print head. If the plastic in this gap melted it then formed a plug which blocked everything up. All I had to do was take the printer to pieces, put it back together wrongly a couple of times and then finally get it right.

So I know have a 3D printer that works. As far as I know.

Maketober Day 17: Making a broken printer

Una my lovely 3D printer is what I call a “Schrodinger Device”. She’s got this title in honour of the celebrated “thought experiment” involving a box containing a cat and something that might, or might not, kill the cat. The idea is that right up until you open the box and take a look inside you don’t know whether the cat is dead or not. From a quantum perspective you can regard the cat as both dead and alive until you find out what has happened. The same kind of thing happens with Una. At any given time I may or may not have a working 3D printer. I only find out which is true when I try to print something. I’ve owned many such devices in the past, including a Mini Traveller that sometimes was a car and sometimes wasn’t.

Anyhoo, today when I tried to print a box for a LED panel that I’ve been playing with I discovered that Una is no longer a printer. I’ve spent most of the day proving that this fact is most definitely true. In this time I’ve replaced some bits, recalibrated others and cursed all of them. Oh well.

3d printing is still hard

We’re trying to get Una the Ultimaker back to some kind of printing shape. The shape above, called Benchy, is supposed to be hard to print. The first attempt didn’t turn out too bad, but I think we have a little way to go towards printing perfection.

Back printing

Well, that was quick. Thanks to 3DGBIRE for super fast service. I’ve replaced the Bowden tube and the knurled bolt too, so now my filament feed is super smooth. And I can print at a much lower temperature now that the print path isn’t quite so bunged up.

Still supported after all these years....

I’m not sure many companies are still providing support for eight year old products. Apple make a big song and dance about how they provide updates for their phones for “at least five years” after manufacture (which I think is a bit rubbish bearing in mind how much they cost). I find it amazing that tech companies are allowed to get away with this. Nobody else (for example car makers) is allowed to call time on their products in this way.

Anyhoo, rant over. Today I contacted Ultimaker about replacement bits for Una, my printer. I’ve found some things on Ali-Express which look like they might fit, but they have a twenty day delivery (if I’m lucky) and so I thought I’d go back to the source. They put me onto their UK dealer who had the parts I need in stock and they are in the post. Should arrive tomorrow. Awesome.

Una has fallen...

Una, my Ultimaker original 3D printer, has been happily printing out bits and bobs for the last week or so, although I have been needing to use higher and higher printing temperatures to get a decent flow of material through the print head. Not a thing that should be happening on the way into summer. Anyhoo, today I set her off as usual and went back to check on progress, only to discover that she had been waving her print head around for an hour or so, printing nothing.

So, I took everything to bits to discover that the filament had melted into the end of the Bowden tube (the tube that delivers the filament to the print head). This has produced a pretty solid blockage which is not going anywhere in a hurry. I think it was caused by the little PTFE fitting (the white bit in the picture above) wearing out and collapsing.

So, no more 3D printing for a while. I’m going to have to track down some spares.

Making trivets

I love the way that 3D printing lets you go from an idea to a thing really quickly. Thanks to a what seems to be a worldwide shortage of liquid soap (I wonder why that might be) we now have a soap-powered cleanliness routine. This has led to a need for soap dishes. We’ve re-purposed a bunch of little dishes, but we have the problem of the soap getting wet and icky (and dissolving) in the dish when it gets wet.

We needed something to keep the soap out of the water that runs off it after use. A kind of “soap trivet” that fits in the bottom of the soap dish. A few minutes with OpenSCAD and I had my design. A little while later we had our printed trivets. And now Una can go back to making PPE visors.

If you have a need for a soap trivet, you can find the OpenSCAD code here.

Hull PPE Facebook Group for Covid19

If you’re in Hull, have a 3D printer and want to get in on the visor making action there’s a lovely Facebook group you can join here.

Printing Visors for Covid-19

I noticed that Paul was printing out visor holders for health workers. I thought I’d like to have a go and he was kind enough to send me his design of choice. Of course Una (my 3D printer) promptly decided to play up massively. At one stage I resorted to shouting “I’m trying to do something good here!” very loudly at her. That didn’t work and so I replaced the print nozzle for one that actually had a hole in it.

This improved matters considerably, and after a couple of hours I had my first prototype. You are supposed to use A4 plastic binder covers but, not surprisingly, these are a bit hard to get hold of at the moment.

I’ve ordered a bunch, but for now I’m making do with some transparency film that I had lying around for printing out overhead projector slides (remember them). I’ve also ordered some proper length elastic bands.

The finished article looks OK to me. I’m going to wear it for a while just to see how long it lasts. Now all I need to find is someone who wants a mask like this. I’m not saying it is perfect, but it beats the heck out of nothing…..

If you have such a need, let me know

The first rule of 3D printer alignment

The first rule of 3D printer alignment is:

It doesn’t matter whether all the calibration settings are what they should be. It only matters whether it prints or not.

Bad printer...

Let’s just say it’s not going as well as it could…

Fixing Una

Whenever I start to think of my 3D printer as an appliance it promptly breaks. Actually, this time it was my fault in that I started a new print without removing a completed one. The resulting crash was quite noisy, as the rubber belts did what they are designed to do, and slipped.

The printer itself seems undamaged, which is a relief, but I figured it was time to show Una some care and attention. After all, she is nearly eight years old. And I have got a replacement set of belts and a new print nozzle to fit. So I took everything to pieces…..

One of the principles of 3D printing is that any given job on a 3D printer will take a day. Even if you think it will take a couple of hours. This one was no exception, but by the end of the day I had the belts replaced and print head back in position.

Next I just have to level the bed and adjust the distance of the head so that it prints properly.

Winning and losing with the led cube

It turns out that sometimes the only way to find out how to do something is to try and do it. That’s what I’ve been doing today. I’m building a cube out of LED panels. And today I ran out of reasons not to start assembling the parts. Above you can see one of the led panels that are going to be the faces of my cube. I’ve removed the original chassis from the back of the panel and fitted one that I printed yesterday. The new chassis is slimmer and has bevelled edges that let the sides fit closely together.

My printed panel fits exactly (more power to you Una the Ultimaker). I just had to remove the teeny tiny screws that secure the panel to the original chassis and then refit them into the the newly printed chassis. This is a fraught business. The screws engage with really tiny holes in the panel circuit board. If the screws miss their holes they tend to cut through tracks on the panel (that’s one panel broken). If you try to line up the panel with the chassis by pushing a pin through the hole in the pcb board this can catch on the leds on the front of the panel and remove them (that’s two panels broken)….

I managed to fix one broken panel by scraping the paint off and then re-making the connection with a blob of solder. The other panel has three LEDs on one edge which don’t light up red. Oh well. I ordered one extra panel in case of problems like this and I can still use my “broken” one in a picture frame as I just have to crop out that three pixel column from the side. On the whole, I’m going to call this progress…

If you want to see the work in progress I’ll be taking all my bits to the Hardware Meetup tomorrow. You can sign up here.

Untitled Goose Printing

If you’ve got an Xbox Game Pass you play Untitled Goose Game for free. And you should. You take the role of an annoying goose with a mission to cause havoc. The pace is nice and gentle and the animation and drawing is really well done.

And number one son has found a design on Thingiverse to print our very own goose models. You can see my first effort above. I need to work on the layering a bit but overall I’m very pleased with the results. You can fit a magnet into the beak so that your goose can hold little metal objects.

The design supplied in for the white, yellow/orange and black parts. We’ve found that ordinary “superglue” (cyano-acrylate) does a good job of holding the parts together.

My goose has a slightly rakish stance because he fell off the desk and broke his foot off which I had to glue back.

3D Printer Tip - use good quality filament

I remember a while ago someone saying that the average 3D printer can produce output with the quality of “the toys that you can find in a Christmas Cracker”. Well, we are making our own crackers this year (just for fun) and I’ve found a nice set of animal shapes that we can use. I dropped the designs into Cura and sent it over to Octoprint for printing by Una, my venerable old Ultimaker One. She’s seven years old now, but still prints really well.

I think one reason for the quality of the output is that I’ve stopped buying cheap filament. A few years ago I went through a phase of being impressed by 1Kg reels of printable materials available for only a fiver. I tried a few and the quality varied a lot. And some had the habit of snapping off during feeding, which meant for loads of fun getting the broken bits out of the print head.

I now use this stuff. It’s not cheap, but it is not stupidly expensive either. It is consistent, adheres well and the colours look good. And it comes on nice spools. Bearing in mind the time it takes to print stuff, I’m unlikely to use a hugely expensive amount of it.

Awesome Overhang fun

So I’m printing some camera clips on Una, my Ultimaker (seven years old this year). I forgot to ask for support for the print. I needed support because the top half of the clip just sticks out into the air. If I’d asked for support the gap on the left of the picture above would have been filled with removable printed bits that support the “ledge” that is being printed.

However, when the print finished I was impressed that even with the lack of support I’d got something that is probably usable. You can see the dangling loops of filament at the bottom of the ledge but after a few layers they had bunched together enough to get enough material to complete the print.

I’m not proud of my inability to specify support when a print needs it, but I’m very proud of the way that Una coped without it.

Octoprint is wonderful

I mentioned on Sunday that I was a bit worried about the SD card reader on my lovely 3D printer being potentially unreliable. For years (seven actually) I’ve been writing my gcode files onto an SD card and then plugging into the printer for each print. This is probably not a good idea (and hasn’t been one for a while).

Anyhoo, a couple of failed prints on Sunday left me wondering about a better, and less physical, way of connecting the computer and the printer. I could just plug the printer straight into my computer, but I’ve never been keen on doing this. Knowing my luck the Windows 10 update process would steam in and break a print 8 hours in.

So today I took a proper look at Octoprint. Its a server that you attach to your printer. It gives you a lovely web interface that you can use to manage your prints and it also has a plugin for Cura, my favourite slicing tool so I can just open the files in Cura and then send them straight to the printer.

It’s wonderful. The installation is a breeze. There’s a boot image for Raspberry Pi that you just have to copy onto an SD card and you are in business. You don’t even have to attach a keyboard and screen to the Pi you are using a s server because you can do it all over SSL and via the browser.

I’ve done a couple of prints and they’ve worked very well. The next thing I’m going to do is attach a webcam to the server so that I can view print progress remotely.

If you have a 3D printer and a spare Raspberry Pi lying around you should definitely take a look at this.