Box Fan High-Pressure Mod - For LASKO

Whether you're building a filtration unit to filter out wildfire smoke in your home, a dust collector for the shop, or simply looking to get a bit more bang out of your Lasko fan, this relatively quick box fan mod significantly improves the airflow from your fan and allows it to more effectively push / pull air at higher pressure, especially when obstructed with one or multiple filters.

Made up of eight easy to print parts, this mod works by making your fan into a far more effective ducted fan. By closing the distance between the blades and the frame, this mod simply prevents air from recirculating around the ends of the blades and either, being pushed back out of the intake, or being ingested from the sides rather than front.

Included in this download are eight, ready-to-print, high-resolution meshes along with a visual project guide outlining all of the steps and tools required.

Will it work for other box fans? Probably not, though if you send some dimensions we could work out a design for your particular fan!

These parts are pretty easy to make so go with the material you deem best. One thing worth noting (if it matters to you) is that finding a filament that matches the color of the box fan is pretty tricky, some are too white, some are a little too yellow - we found Hatchbox PLA to be pretty close.

If you want to save on material, print with a single shell, sparse infill - though we had best results printing with two shells and about 12% infill - that way we could print without using any supports at all and the overhanging sections would turn out great; with a single shell, the overhangs got real messy. Also recommend printing with a skirt since there's not a lot of surface area at the bottom and because the parts will try to lean further and further forward as the prints grow higher - two layers, six perimeters, 0.00 offset worked for us.

Apart from that, we recommend just practicing good printing habits such as: make sure you dry your filament - dial in your print settings before printing - print on a PEI, gluestick, or with some circle pads / skirt if bed adhesion is a concern - print in an enclosure if you’re worried about warping and layer adhesion (especially if printing PETG, Nylon, or ABS), and don’t start assembling anything until you’re confident you’ve got a strong / successful print that you’re willing to work with (don't hesitate to reprint if necessary).

Lastly, if your slicer software doesn’t automatically interpret the correct units / scale try scaling by 25.4% (if it imports really small) or 0.0393701% (if it imports really big).

Please feel free to reach out if you get stuck or need help at any point in the process.