Dyson DC31 extension parts to function like a DC35. Requires a donated tube. I used a metal tube (outer diameter 28.7mm), but you could use a rigid plasitc tube. You also need to add a small spring for the catch. The one I used is 19mm high and 9.5mm in diameter. It was included in this set: http://www.jaycar.com.au/productView.asp?ID=HP0638Seems to work fine with plenty of suction, but use at your own risk.You can use these parts for any other extensions or heads that you want to design.Designed with Alibre.There are three parts:I printed them in PLA. Male and Female with 50% fill, catch with 20% fill. Male prints without supports as oriented in the file. The other two require supports, I have oriented them the way that I printed them.Inserting the catch into the female part is a little tricky. Place the catch face down onto a flat surface and place the spring into the depressed circle, as shown in the photograph. Gently squeeze the catch together where the pins are (marked by the arrows) with some long nose pliers and then lower the female part onto it until it just fits in, then wiggle it down until the pins engage in the holes.Fixing the male and female parts to the metal tube is accomplished with an interference fit. I needed to soften them in boiling water before pushing them on.