Hotend part nozzle - a story of over-engineering in Solidworks

As some of you may know I have been teaching myself how to use Solidworks, an incredibly capable CAD modelling suite.

I’ve tried to get into this by designing a part; this weekend I spent time creating the E3D Volcano hotend in Solidworks from the drawings available on the wiki, which was an excellent exercise in getting to grips with it.

The part in question is a part-cooling nozzle, to cool the plastic as it is extruded. This will be mounted onto two ‘squirrel cage’ blower fans, either side of the hotend - as so:

The nozzle swivels on another part, to make it easier to print. I was happy with the shape, as it clears the bed and probably blows air over the plastic and not the nozzle.

This is when @Cylindric suggested I play around with the flow simulation feature of Solidworks. Uh oh!

After being able to see some turbulence on the inside of the nozzle, I altered the ‘whistle’ shape of the nozzle until it got better. I also made a few changes, such as filleting the inside edges to make for a smoother transition and editing the end of the nozzle shape.

As it’s certainly worth sharing, this is the resulting flow simulation :slight_smile:

And of course, a short video to demonstrate the animation aspect:

I don’t think you over-engineered it, I think you engineered it just right. Nice work.

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I have no idea really, but to me it looks like there will be quite a bit of back pressure with that nozzle. For effective cooling I think you want maximum volume of air.

Thanks for your comment, I certainly think you’re right. I have more or less been following/plagiarising the style of cooling nozzles that are available for printers. I was tempted with a ‘shroud’ style, but this seems a little more difficult for the end result; I’m planning on having the fans swivel, on the back will be a microswitch mounted for homing, and a shroud style might be make this more cumbersome.

With this design I was trying to avoid any cooling of the nozzle whatsoever, hence the narrow aperture (there’s not a lot of space between the bed and nozzle, and I imagine diffusing air could hit the nozzle if it was too far back).

I suppose it’s a trade off between airflow and directionality, you don’t want to cool everything, otherwise you make your bed heater inefficient.

Oh well :smiley: best thing about printers are it’s easy to prototype this kind of thing! I’m hoping the results will speak for themselves, but the nice thing I have discovered about Solidworks is how easy it is to iterate over your design and tweak things.

Well it looks really great @Jagmills — Its inspired me to get back to some projects I had going in CAD using Fusion 360 which involve motion studies etc.

Am I reading the scale on the flow simulation right? Its saying the output will be about 350ms¯¹ which seems very, very fast. Look forward to seeing how the fabricated part turns out and how the CAD workflow has affected the performance of the final part.