onsdag 24. juni 2015

3D Printing and spray painting large multi-part model.

I've always wanted to do a huge print of a statue of some sort on my printer, and I finally decided to print the famous beautiful owl statue by cushwa.

Here's the finished project.

Preparing the model for printing

Picture from thingiverse

I used netfabb Basic to cut the model into slices. I originally wanted the owl to be closer to 50 cm tall, but since the base of the owl is approximately square I would have had to print a lot more parts (as in ~16) to get finished. I therefore scaled it up to fit my 20x20 platform and cut it in three pieces to print.

I sliced it with Slic3r it with several perimeters and very low infill, to save time and plastic. I could have gone with even more perimeters and ever lesser infill on the centre parts instead, the result was more than rigid enough.

Printing the middle part on my trusty Mendel90

I printed with scraps of remaining plastic, which was a bit of a bad idea.

Here is the finished print before any painting is done.


In total it was printed in four parts due to the filament clogging up a few times, so I had to measure and cut it several times in netfabb Basic. Notice the visible seam on the very top with the ears, and how they disappear later.

Attaching a model like this together was a bit tricky at first. I tried to heat the centre of the print to make it stick to the previous part, but it was impossible to heat a area that large fast enough and attach it together before if cooled of. So I ended up attaching using a soldering iron along the edge only, and it held up very well.

First I ran the iron through both parts, leaving some ugly but strong anchor points. Then I ran the soldering iron along the edge smoothing it as best as possible.


First I tried some plastic primer, but it reacted with the PLA in some way, and made it all soft. Instead I started out with this spray filler from Jula (norway/sweden). It was not as thick as I expected so it needed several layers with sanding in between, but it is very nice to work with.

First layers of spray filler.
Notice the visible lines in the eye sockets.
The spray filler was not thick enough to remove the larger seams,
so I added some wood filler. It all bonded surprisingly well.

I also had to sand it several times between spray filler and wood filler to make it smooth.

I really liked the colours in this shot.

I do believe this was the final sanding stage.

The back is feeling real smooth now.
The top still have a few layers of sanding and smoothing left,
but it looked real good with the soft shine and reflections. 

I was considering painting with a gloss paint at this stage instead.

From the front, all shiny.

 Granite effect

I used this granite effect spray. It was very different to work with than regular spray and had to be painted on in very short bursts to avoid running. Luckily it dries very slowly (as in days) and you have plenty of time to wipe off and redo any mistakes.

For being handling safe it needs to be painted over with some kind of clear spray.

First test with the granite effect spray resulted in horrible running.

The granite effect hid the seams and lines extremely good.

After days of very thin layers of granite effect,
 I gave it several (can't recall exactly how many, but at least 5)
layers of  clear glossy paint.

Painting with the object laying like this was the only way to paint under
the feathers of the body, as the granite spray really doesn't like to be applied sideways.

Final result 

Here are a few shots of the final result.

All the equipment used.

Thank you for reading, I do hope this inspired you to print something huge on your own RepRap. :)
Feel free to ask any questions about the process!


tirsdag 23. juni 2015

3D print, railway model scenic grass and clear spray paint?

Inspired by Frits I bought some static model grass off ebay and tried it out on an old print from the shelf.

First I tried to use automotive spray glue, the kind you use when applying fabric to doors and such, but it was way, way to gooey and made a mess of the model. Since I didn't have any other spray glue, I tried applying a layer of clear spray paint and poured the grass over it. It stuck surprisingly well! I applied another layer of spray on top of the grass and poured even more grass over it, thus leaving it pretty well covered.

Here are a few pictures.

For a first test I'm very satisfied. It will be interesting to see how well it holds up, but it didn't fall off when touching, and the spray made it pretty static leaving an interesting looking effect.

The problem with a model this detailed is all the fine details is gone, this could be due to me applying several layers.

I will try with some landscape model printed in green plastic, to see how well it looks then.

Edit: I just tried rubbing it a bit, and it turned out most of the grass held on by surface tension. So the details wasn't that washed out, but also it was not very well covered after all,  and not handling safe in that state.

Thanks for reading!


fredag 12. juni 2015

How I broke a brand new E3D Lite6

Update 2015.06.23, E3D going above and beyond.

I messed up when trying to extract the nozzle, and the extractor broke off inside the block, making it near impossible to fix.
Driving out a drill bit with a drill bit
turned out to be difficult, as the softer
metal in the block gave away.

The issue with the nozzle breaking was due to me not following the nozzle swap procedure, which has to be done at 245C... As well as the liner compressing thus forming a plug.
I always ment to pay for new parts, but E3D actually gave me store credit to buy a new one(!) which was far beyond what I would have expected.

From E3D/Sanjay email: "The reasoning for me providing a replacement is that I think there could be an issue with the tube/lining coupling, and that there may be an issue on the internal bore which prevented you from inserting your liner fully. I am absolutely certain that the leaking you experienced is a result of the nozzle tightening procedure not quite being performed properly. You should be able to solve any leaking issues with a quick nip up and tighten of the nozzle when hot."

I'll report back with a new modified wades and my experiences with a more carefully assembled lite6.

Original post:

I just finished building a Mendel 90 sturdy for the school I work at, and started printing today together with my students. Everything worked pretty well and we did a few various prints, they really enjoyed this one. 

The extruder is the standard 3mm wades that comes with the Mendel 90 source, printed in ABS. I drilled out the filament path to fit the PTFE liner and just used it stock like that.

I had some issues dialling in the extruder settings though, and had to increase the extrusion multiplier to 1.1-1.2 to get acceptable solid prints, but there was still a lot of stringing. After a while I chose to remove the extruder idler to have a look inside, and I saw this.

The bottom PTFE liner should be flush with the plastic,
but it have moved quite a lot upwards.

The collet looks like to be in the right position.

I removed a good chunk of plastic to avoid moving the collet when inserting the hotend.

Teeth looks fine, and have not clogged.
Since this is the 3mm version, and the filament path hole is not moved, the idler does have to be tightened almost all the way, and the bearing does bend the filament slightly. But since there are no clogs, and it was easy to change out the filament, I reasoned it would be fine.

The nozzle is positioned correctly according to the assembly instructions.

I had to heat the hotend to 120C to unscrew the nozzle.
This is what it looked like.

The filament is pulled out and clearly shows the
PTFE liner was not completely flush with the nozzle.

Slight leaking from the top of the heat block.
After looking at it a bit and reinserting the PTFE liner a few times, I felt there was a tiny edge at the bottom of the heat sink, and you need to use quite some force to push the liner past it. I figured I rather push the liner through the heat sink and the heat block and then screw the nozzle into the heat block moving the liner upwards to make sure there is a tight fit.
Update: This was a terrible idea, the liner got compressed and probably had a lot to do with the nozzle breaking.

I started screwing in the nozzle with the liner like this. 

It was quite hard to screw the nozzle back on, possibly due to the plastic left in the threads, so I heated the hotend to 120C to make it soft and started out. Then...
Seems like I need a new nozzle, liner and heat block..

Any ideas to what could have caused this? I followed the instructions very carefully. The collet was properly secured, I could not move the PTFE liner up and down by hand. Thermistor settings were correct. I ran a M303 to ensure the temperature didn't overshoot, before heating to 245C and tightening the nozzle.

My guess is I only got the PTFE liner down to the small lip inside the heat sink opening, and there was a gap allowing the PTFE liner to move.

I'm in contact with E3D support already (they answered very fast), and wrote this post to better show my problem to them and to help others avoid the same mistake.

Thanks for reading!

onsdag 22. april 2015

Everyday practical use of my RepRap 3D printer - Part 3

After I did part 2 of this type of post (here is part 1 if you're interested), I started to realize just how much stuff I have actually printed in the last 4-5 years. It really does attest to the quality and usability of DIY 3D printing when you don't notice you are using 3D printed parts in your daily routine.

Here's some more - though still not all - stuff from around the house. A few are from thingiverse, but most of these are custom built with OpenSCAD. Feel free to ask if you want a certain model for something, and I'll be happy to share the probably terrible rough and ugly code with you.

I've just linked my blog to g+, hope it works out as it should.

Edit 05.05.2015: Fixed some spelling errors and added a little more information here and there.

Enjoy! :)

First out is my vesa-mounted raspberry pi (named Anton) which I intended to use with XBMC. I felt it was too slow, and just installed KODI on the desktop computer instead. The raspberry will be used for OctoPI instead.

The cool thing with custom casing is you only make holes for the connectors you need. I also built it so the SD card is located inside the casing to avoid it breaking of.

Next up is mounting clips for some mood lights inside a bookshelf.

I was worried the heat from the light strip would melt the PLA, but it holds up after more than a year of prolonged use.

More clips, this time for some extra support for a LED strip in the kitchen. There is tape on the back, so one nail is sufficient.
The LED strip above is driven by a small PSU, which I have mounted using some 3D printed brackets. The PLA holds up to the heat very good.

What do you do when the handle of your wife's new seam ripper is too short? You print an extender, naturally.
A custom built bed needs custom built lamps. The lamps are from IKEA, and come with a huge clip to attach it to a desk. I removed said clip, made a housing with a trapped M8 nut inside, and soldered on a new switch. 
Another shot of the housing. As a extra feature it hides the screw I used to secure the headboard to the wall.
One of the mobile phone stand I have, which works pretty good. There are a lot of these around so I didn't take the time to design my own. This one is from thingiverse.
The shower soap cup from 2012 eventually broke, so I printed a stronger replacement. Also notice the hooks to the right. 

And there are also matching towel hooks. PLA is surprisingly strong, and I have yet to break one of these off. 

This neat nose glasses support is really tidying up the desk, and it help to recover misplaced glasses.
Another glasses holder. This one fits this type of eyewear frame very well.

Another bracket which takes a lot of daily abuse without any problems. I added a small piece of foam to the end of the rod so it is supported quite well between the walls.

You don't want your baking yeast all over the refrigerator? A 3D printed box is the solution for you! In this case I went for not only practical but also a little aesthetic. The weaved pattern was a fun OpenSCAD programming exercise!

A bit tough to photograph this one. We added some nice knobs to a dresser, but said knobs had some pretty nasty bolt heads which could rip clothing in said dresser. Tape? Nah, 3D printed cap of course. I heated it slightly with a lighter and pressed it on. Not one of them has fallen of yet.
Here's a painted knob on the same dresser as above, with a 3D printed butterfly silhouette. The filament is the great looking Galaxy Blue from Faberdashery.
Curtain rod holder? Sure!
Another one? Definitively, but lets sneak in a RepRap logo this time around.
Home sewn curtains needing a curtain band holder wall screw thingy? No problem!

IKEA RUSCH clock remastered with new numbers. The paint came off when reinserting the face plate, and the inner workings are not very beautiful. First time I glued the numbers on I hang the clock before the glue was totally dry, that resulted in a serious persistence of memory drooping. I consider this clock a failure, but hey, it works.
3D printing + textile ink = awesome. It did take a number of tries to make this work though. The first layer / glass side have to be a little overly squished to make clean edges appear, and the paint is best applied slowly with a brush. But the result is looking very professional!
This clip holds together the neck of a hair dressers apron my wife sewed.
Wall mounted shoes? No problem! Also notice the bootstyled clothes-peg at the bottom right corner. (I didn't remember I printed that until I saw this picture).

Tree rings holder in use for about three years now. The grey flower and the black owl is a few examples of all the jewellery I've printed.

Soggy water at the end of your tooth brush? No thank you!
Portal Waste Disposal Unit Accessory A have been working tireless for 2 years, but the arm of the man have finally broken. This is one of my favourite pieces. 

 So there you go! I, for one, is looking forward to what I'm going to print in the next year.

Have a splendid day folks!