RC brushless turbine as alternative flowhood fan for mycology

Recently it occured to me that this 20KRPM brushless turbine i have that i can buy rather cheap too, incredibly efficiently consumes 300W of power. On paper, a 12″ x 24″ (~30x60cm) H14 Hepa can operate above the required 0.5m/s airflow with a mere 50-80W fan. One of the downsides of induction fans, the most common high power fans, is you cant change their speed unless they were designed with that functionality in mind. Ones that are, usually are incredibly expensive, offsetting their value. Usually a flowhood motor costs more than it needs to because it needs to work unregulated matched perfectly to your filter, producing more than 0.5m/s airflow while also not exceeding the pressure rating of the filter.

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Edge frame complete, example assembly done

The long edge frames have been finished, the only remaining structural component is the vertex joints, but now that i figured out the formula for expressing the angle [ 2 arctan( (1 + √5)/2 ] the end joint will be a piece of cake. The assignment is due soon, ill post some specific geometry later after i submit it to avoid plagiarism detection issues.

hopefully the frame holds up in practice, fortunately to stress test it i can use a short extrusion, and some random 3mm thick material to substitute the plexiglass pentagon. i only need to more or less eyeball it to get an idea of how it all fits together, based on the angle i can aproximate the distribution force (thanks engineering statics) in my head and determine if the printed frame is up to the task or not. Certain issues can likely be resolved if i rotate the frame in a weird way to change how the FDM layering fails. top to bottom with the layers horizontal it makes the layers prone to snapping under 90 degree angle force as illustrated below

if i can make the fault lines much longer i can make it stronger, the perfect way to do this would be if i printed it vertically, unfortunately my printer isnt tall enough and this would demand an INSANE amount of support material to work. what i can do instead is flip it onto the diagonal side there, this would strengthen the frame considerably on that side, and though only slightly on the opposite side, it would still be stronger than purely horizontal. theres various other ways to improve the design, this is just one of the simplest ones that doesnt require changing it at all. A very simple one i could implement with only a slight change would be splinting those narrow walls, although if i printed a tiny hole it would fill, that area would still be a wide solid patch with no hole and could be drilled out, not that id need to, i could insert a heated metal pin into the diagonal “hole” (with a perfect print there would actually be a hole), 2-3 per side would protect it againt snapping. the ideal method though would be to find a way to get some high tensile metal to bear the brunt of the force.