We all hear about 3D printing of this and that, I was sceptical about 3D printing in general but about 18 months ago I saw a Youtube video of someone printing carbon fibre filled PLA filament on a Dremel 3D20 printer, at that point I thought the process looked mature enough to produce some useful and useable parts for competition models.

I purchased a second hand Dremel 3D20 on Ebay for £200, it was like new and worked straight out of the box.

About 2 weeks ago my RC pylon racing partner Nathan Attridge said he wanted to try a 3D printed pattern for a small pylon race model (950mm wing span) that Nathan was dragging into the 21st century, I was sceptical about this as we normally are slaves to 3D machining using the best materials and machines that we can lay our hands upon.

However I am always mindful of the time that we spend machining patterns and moulds and thought lets give it a go.

The printer has a volume of 230x150x140 so this means that the pattern has to be split into sections, the fuselage was split vertically into 7 sections fore and aft and the canopy into sections split down a vertical centre line.

The filament used is Protopasta PLA with a layer height of 0.2mm and a 10% infill, the pattern sections look very useable and will be stuck together with a central alignment mandrel, then some sanding, fairing and ultimately primed and polished.

This might be a useful technique for CL speed cowls and fuzes, I doubt that the process is stable enough for wing patterns though. I do know that some people are making prop moulds off of 3D printed patterns but have not seen the results yet.

B.

PS nothing like the beauty of Jimbo's Weatherman pattern though!!