This is a system I built several years back at the old shop.
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area in front of the filter bank was used to finish solid surface countertops. These days, it is a sanding room for many jobs. The floor space is not used up with this set-up and I thought it may be of some inspiration for other, smaller lay-outs.
I paid, IIRC, about $ 500.00 for the used furnace blower, heavy-duty switch, and MDF.
The filters lift out and are a standard size.
By no means is it a perfect system, but it really works well, especially moving some valuable heat around.
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