Category Archives: Special Projects

This one was a bit of a pain!

Here is a rather large 6th order Sierpinski sponge printed on the Anet A6 3D printer using Rigid.Ink white PLA.

All was going well 120-hours into the print – when I got a nozzle clog.  This meant the top portion of the pyramid didn’t get printed.

Luckily there are some pretty clever people on the 3D printer forums and one guy suggested I use Ideamaker to just select the missing bit of print and then print out the missing top section separately.  First attempt at doing this I didn’t choose a big enough section to reprint and it only just slightly didn’t fit.  Wanting a perfect fit I had a second go, this was in itself a 9-hour print just for the missing top bit – and fortunately this time all was o.k.

So here is the longest print to-date on the little Anet A6 – 129-hours on a Sierpinski sponge.

Klein bottle experiments with the Anet A6 3D printer and Rigid.Ink Trans Blue PLA filament

A Klein bottle only makes sense if it’s transparent so you can see what’s going on inside.  Not that easy to make transparent/translucent 3D prints.  Here you can see 3 different Klein bottle prints using an Anet A6 3D printer and Rigid.Ink Trans Blue PLA filament.

The leftmost bottle is a 0.8mm solid double-wall print – even back-illuminated you cannot see what is going on inside.

For the middle Klein bottle – I have cheated.  That is a 0.8mm solid double-wall print of a half Klein bottle – the bottle has effectively been cut right through the middle, at least that way it is clear what is going on inside.

The right-hand Klein bottle is a 0.8mm SINGLE-WALLED print!  Being translucent you can at least see what is going on inside.

I think we need a 3D glass printer to get what I’m really after.


Pythagorean Cup

The cup with the funny bit in the middle is a Pythagorean Cup – 3D printed – 13 hours and 160 gramme of filament.

A Pythagorean Cup is a weird beasty – it prevents piggy drinkers.  If you fill up the cup to below the line on the rim (below the top of the domed piece in the middle) then you can drink from the cup, no problem.  If you fill the cup to above the line, then a siphon (which is within the domed piece in the middle) will empty the cup through a hole in the base all over your lap.

Sierpinski & Menger Sponges

The 3D printer has been working overtime recently turning out fractals.  Here we have Sierpinski (triangles) and Menger (square) sponges.

These objects are 4″ on a side, the Menger Sponge is 4th order and the Sierpinski Sponge is 6th order!!  Both are 0.2mm resolution printed using white Rigid.Ink PLA and a 0.4mm nozzle.

The Sierpinski Sponge was a modest 30-hour print and the Menger Sponge was a humungous 65 and a half hour print.

I am thinking about printing a 5th order Menger Sponge, again around 4″ on a side – but this will take around 90-hours in total.

May also print a larger Sierpinski Sponge at higher resolution (0.1mm).

A 31-hour 3D printer print – the Roman Surface

Another marathon mathematical object run for the 3D printer – this time the Roman Surface (seen here in front of a Klein Bottle).

I had generated this surface years ago using Mathematica and had spun the object around in 3D, but still couldn’t quite assemble the thing in my head.  Now I can hold it in my hand I can see it clearly.

The 3D printer has been taking such a hammering with these extremely long prints that the X Y bearings are now sounding a bit klunky.  New bearings are on order.

The Anet A6 Does the Klein Bottle

After printing out the Sierpinski Triangle I thought I would go for a LOOOONG print.

So I went for a Klein Bottle (see Cliff Stoll’s You Tube presentations on the Klein Bottle – they are excellent) and a BIG one.  The Klein Bottle I printed out ended up 8″ tall and 4″ across the base.  This was printed at 0.2mm resolution and the print time was 18 hours!

Clearly it was a mistake not to use transparent filament for this object (or indeed for ANY 3D mathematical object) but that has been rectified by me ordering “natural” and trans-blue filament from Rigid.Ink.

In the meantime I thought it might be interesting to illuminate the Klein Bottle to see if it revealed the internal structure.  It didn’t – BUT – it did show up very nicely the printer’s print pattern in the wall of the bottle.  This is in fact the strengthening framework that lies between the inner and outer walls of the bottle (the walls are not solid).

The clear filament arrives on Monday – I will then need to give this one another shot.