Monday 14 November 2011

Thing-a-Day-Part2 - The Tricky stuff...

Part 2 of my Thing-A-Day quest - These get progressively more complicated and tricky.

Firstly one of my most favourite objects ever, and modelled so very well by tc_fea - the great Nautilus Shell 
I always planned to print a full shell so I simply scaled this print and made a mirror image for the other side.

I used the1.5mm version and scaled it by 2.5X so the shell walls ended up about 4mm think, good for support, but made this a long print (about 3 hours). My files for both larger halves can be found here.

For a test, I printed one half with the external fan and the other without, it didn't make a huge difference to the outside surface with this print, but the final overhang section was much better internally when using the fan.

Then I could put if off no longer, I had to print the Purple Tentacle! by Bluemetal but I wanted it bigger, so my version is sliced in two, scaled and printed BIG. 
This used the fan to blow gently across the hollow print
He is also filled with some beads and makes a great sound.

After the Tentacle came the Hollow Halloween Pumpkin by Kaetemi printed as a challenge in our local reprap meetup in October.
This was printed with just 1% infill for speed and an experiment to see if 1% works. Using a small fan blowing across it printed reasonably well and the low infill % had a nice side effect of glowing with a light on the base.

It has a fault line on the lower half, this was where the orange filament ran out and I had to run across the room and stuff in more without stopping.

After printing the original I uploaded a mega pumpkin challenge (maybe for next year) you may need a whole team to print it all. Please let me know if you attempt it!

Next I wanted to try something really complicated, so I was searching Thingiverse for organic shapes and 'tricky' things, I found a few Brians and selected this one as it looked most detailed and complete.

Human Brain by jmil

I sliced it in half so I could get a nice flat surface and also so it would fit on the machine, this was the most complicated thing my machine has printed so far.

Base of the brain.

Top of the brain.

Skeinforge spent many hours slicing the model and at just 8% infill each half took over 9 hours to print. It has so much detail, much you can't see as it's deep in the folds and cavities, no picture can do this one justice, but here it is assembled -The Gcode for each half is around 30MB, (using small Gcode output) that's a LOT of machine moves!

That's the closest I ever want to get to a real brain.
It even looks a little wet and 'brainie' with a close-up.
I love the fact it was imaged by MRI slicing and then assembled into a highly detailed 3D object, and we print it in slices again on a 3D printer. I can't imagine any other fabrication method could make this object as well as a 3D printer.

So after all that printing I has a special request for  'Holly' Magic Wand from my little girl, the files can be found on Thingiverse Here  'Holly' magic star wand - pencil topper by RichRap

The design spec - 
Daddy, Can you make me a 'holly wand'? and I want it to tinkle, and glow and look really nice, and be Purple and Pink. Thanks.

The design was done in Sketchup, some are glow-in-the dark, some have clear backs so you can see the internal letter and some are filled for a mix of glowing, rattling/tinkling joy. - this should be a perfect stocking filler, so get printing now!

Filled with stars, slices of filament or Hama Beads.

Bonus Print - (For Halloween). Glow-by-Night
A monster GLOW-IN-THE-DARK spider - based on the printing plates by MakerBlock
My version was scaled up to just under 2 x the normal size.

Lots of Glow!
Quite a few parts to this spider

And he is really BIG!

And a video showing some of the prints (Hi-Def here on Youtube) or below - 

I really enjoyed doing Thing-A-Day, and I found out new things and new print effects.

There is a little more to this story but I'll save that for another day and another post.

I printed all the things in Thing-A-Day without a single change to my filament size in Skeinforge due to the Faberdashery PLA I'm using being so well dimensionally controlled, I never need to think, is it different? If you swap over filament colours quite a lot and want to use the same Gcode then having the same filament dimensions from batch to batch and order to order is really quite important. I can't recommend this stuff highly enough, it's excellent.

I now have loads more things on my list to print for the future, here is a small collection that caught my eye as I was browsing thingiverse last month, take a look at these below for inspiration and wonderment - 

spinnyJiggyVase by mannytan - Looks insane, one I'll want to watch printing.

Maraca Traditional - 2 Piece by beekeeper - useful and fun.

The OpenSCAD Pirate Ship by MakerBlock  - print without support?

Mechanical Animals by sconine - these are just great on so many levels.

Jack in the box by Sublime - this is looking great, must print some of these with various things inside.

Spiral Lightbulb Sculpture by benglish - must try this without support.

Devilhead 2.0 by yzorg - Wow! Print blood red or Glow-in-the-dark

And when I get my build height back, plenty more of the excelent basic receptacles by MakeALot

Do have some fun with your printer.

Thanks for reading, until next time.


Monday 7 November 2011

Twelve days of thingiverse - Thing-A-Day - Part 1

As a break from printing machine parts and structural objects I decided to print something off my thingiverse list every day for 12 days.
They got harder to print/slice and more complex each day - On the last day I designed my own thing, see part 2 for that.
And of course, I learned a few new techniques and tricks along the way, I'll share with you here - 

Sing along with me - On the first print of Thing-A-Day my RepRap gave to me...

Mr Alligator and a Fractal Tree :)

Alligator by mraiser

Fractal Tree 2 by tc_fea

On the second print of Thing-A-Day my RepRap gave to me...

A Turtle and a 'Dove' tail joint.

Triangular Dovetail Joint by VeryWetPaint

OK, that's enough of that song... It's not Christmas just yet. Below are on my 'all-time want to print at some-point' list, which is growing every day...

My general goal was to try a few things that have been on my list for a while and also some things that no one else seemed to have tried to print, or at least prints with little evidence of success.

So an easy start - 
A nice Pink Gekko by guru was first up -
This showed up a few minor fill issues so I tweaked settings in Skeinforge and firmware and moved on to -

solid gold Honey pot - basic receptacles by MakeALot. the Idea here was to test my calibration and speed of a hollow object as I had plans to test more hollow things shortly.
this was 100% infill just using multiple shells, it produces a nice heavy pot.

The next object was slightly obscure, but I wanted to print it simply because of the first comment made by Raster on the thingiverse page here 
It's the Awesome Cow by JonMonaghan

From the cow I wanted to try something that looked difficult and as per the cow I wondered if it could be sliced in half to print more easily - 
And it could - Behold the mighty Stegosaurus!  by Hurtzmyhead
My sliced Version can be found here

This shows how the low polygon count in the STL model translates to the printed object.

From printing the Stegosaurus he led me to chop off the head of a very fine Venetian Lion Here  as another test in printing something that people only printed with support.
He is hollow and was also 70% filled with Hama beads. 
This is a derivative work of the full Venetian Lion by tbuser.

At some point around here I started filling my other hollow objects with things, 
He has a shiny gold underside.

The Banana Slug (High Res) by scanlime is a fine example of a nice model and a perfect thing to print hollow.

My version is 2 x the size and is filled with Hama beads to give him a nice rattle.

And a version of the great Yoda lite model by faberdasher
This has less robe and more of the detailed face.

I also filled them with various objects and experimented with temperature for a number of reasons.

One test was for my Failed print Blog and the other was to actually see if I could create different effects with PLA and temperature, the answer is Yes as you can see in the photo. With more opaque PLA you can also get some nice matt effects with higher temperature.

Brain Slug by 7777773 was next
Top Tip Here - 
My version is hollow again and was a test of colour filament mixing but I also realised at this point that active gentle cooling of the extruded PLA was essential for a good looking organic (or hollow) prints, so I setup a small cooling fan to blow across the build area after the first layer had been put down, this gives much better results as you can see with some of the other items below, I now always use this fan to blow across PLA whenever I'm printing with it. I have yet to find a situation where it has not improved print quality.

I wanted to print something that could be hollow and also needed to be sliced, so my nest subject was the most excellent model of Roal The Bratty Dragon Prototype by SplotchyInk

My version is bigger and has three sections you can print in different colours to make him look more vibrant.

As an experiment one side was printed with 0% infill and this side shown above was just 5% infill - I had some minor holes using 0%, you can't avoid this on some objects when done hollow, so a low % of infill usually rectifies the issue.
The tummy also needed some infill to stop sagging and collapse of the outer perimeter while building, still a few issues with this print, but a slightly higher infill will resolve this (Extra shells don't always help).

This shows what usually happens to objects like this when you try to print them hollow or with low % of infill
A smaller layer slice height can help, but some infill is almost essential for parts like this. Remember a severe  'overhang' is the same problem if it's going into an object or out of an object.

And a short video of some of the objects, view it Here in Hi-Def directly on Youtube, or below

That's part 1, look out for Part 2 shortly, it'll have some interesting prints, objects and effects.

Thanks for looking, and do try an external fan, you'll be impressed how much better it can make objects print.