Mathematical Slippers

When the colder weather came I couldn’t wear my normal slippers, because I had an injury to my leg a few months ago and it was still strapped up. I decided to knit some.

I looked at various existing patterns but then decided to design my own because I suddenly realised that feet are basically the same proportions, regardless of the size, and it would be possible to create a pattern that would fit anyone.

This is an archetypal Woolly Thoughts pattern. The slippers can be made with any yarn and any needles in any size you want, without having to make a tension swatch. The only maths required is to be able to divide a small number by three.

The slippers can be customised in various ways and are ideal for using up oddments of yarn.

Download the free pattern – Rule of Three Slippers.

An Orchid

Steve recently completed a new illusion knitting design, called An Orchid. It is based on a drawing by Lodygin Sergey Pavlovich who was a Russian graphic artist and theatre designer. There is very little information about him and his name appears in several different forms.

This is a very intricate design. It took well over one hundred hours to chart and probably as long again to knit. Designing is difficult; the knitting is easy. It is no more complicated than our basic sample pieces. It is just bigger. The finished piece measures 104 cm x 132 cm (41” x 52”) so could hang on the wall (if you have a large space) or be used as a bed cover.

As with all illusion knitting, you only see narrow stripes when you stand immediately in front of it. The image appears when you start to move around. The animation shows several different views but photographs never convey how spectacular these illusions are in real life.

The pattern is available to buy on Ravelry.

Curve of Pursuit

Curve of Pursuit has always been one of our most popular knitting patterns so it seemed ideal for turning into a 3D model. This was Steve’s first attempt and it was very successful.

Our original knitted Curve of Pursuit was made over twenty years ago. It was never my favourite because I used yarns I happened to have at the time. The colours could have been better.

The reason people love it is that it can look so different depending on where you place the colours. Buyers often thought there was more than one pattern so, in 2016, we made nine different versions. They were all in shades of grey just to prove that it can vary so much even when using all the same colours.

You can buy the knitting pattern now on Ravelry.


Feeding the filament over the top of the printer meant that the lid could never be put back on. We made spacers from a file we found on Thingiverse. Problem solved.

These spacers seem to be used mainly by people who want to prevent a build-up of heat inside the printer.


The helpful man at Box said it was never a good idea to remove a model from the printing surface while it was still inside the printer because the model could get damaged. He had various suggestions for surfaces that could be removed but none were immediately available, or were expensive, so we decided to improvise.

We went to our local Range (UK household/craft store) and searched for suitable bits and pieces. We found self-adhesive magnetic sheets, two for £1, then went round the shop to see what they would stick to. Some things turn out to be not as magnetic as you might imagine but we did find a rather ugly ‘motivational’ plaque for another £1. We already had some very small bulldog clips.

The thin metal sheet was cut to size and the edges were bound with tape so it wasn’t sharp. The magnetic sheet was cut to size and stuck on to the spare build tape (That’s what they call the blue sheet that goes on the bed.)

The two pieces stick together by magnetism. The metal sheet makes the combination semi-rigid and the two can be peeled apart to flex the model from the build tape.

The new sheet is clipped in place on the original bed.

The next problem was what to do with the reels of filament. The Dreamer comes with two, which fit inside the machine. Filaments of other makes don’t all come on the same size reels. Those we bought elsewhere were too big to fit inside.

The solution was fairly simple. We found a small storage box and an old shower rail. The reels slide on to the rail, the rail lies across the box (which is suitably ridged at the end so the bar doesn’t move about), and the filament goes up and over the top of the back of the printer.

First things first

The printer we bought is a FlashForge Dreamer. We originally intended to buy a less expensive printer but didn’t know enough to make a sensible choice until we stumbled across a company called Box. There are very few places where you can actually see printers in action and ask questions so we took a trip to Solihull. It was well worth it because they had several printers on display and they gave lots of good advice.

We opted for the Dreamer for two main reasons – (a) it is completely enclosed so is not affected by fluctuations in temperature and (b) it has two extruders so you can use two colours in one model.

The first thing we made was from one of the sample files that came with the printer.

The second was a simple name plate using the software that came with the printer. It was little more than ‘drag and drop’. This, and using other people’s files, seemed like cheating.

There are several free CAD programs. Some of them have to be used online which I find inconvenient. There are various others to download so we tried a few and settled on trying to learn FreeCAD. They all have a steep learning curve so it seemed sensible to plump for one and stick with it.

Ben arrived just before New Year and was making glove puppets (Don’t ask!). One of them needed a pair of glasses so Ben and Steve set about designing them. There’s nothing like jumping in at the deep end. They took most of a day. The glasses were tiny, they had to fit, the design was intricate, and the arms had to stick up at the correct angle. The glasses in the photo are the second attempt at printing and, although they are not completely smooth, they look good.