The Freshening Part 2

If I'm going to bring fresh air into my house, I want it to be actually fresh, and that means I'll be filtering out all the pollen and pollution that tends to be mixed with the outside air. To do this, I'll need a filter and, more importantly, a plenum to install the filter into.

So it's back to the sheet metal grind to use up the other ~3/4 of the metal I cut up last week. A basic box is a good place to start.

As we can see this is sized precisely to fit a 12x20x1 filter diagonally inside the 1 inch flange. Coincidentally, the size of plenum needed for this fit is 12x20.

Go figure.

Anyway, the removable fingers of the box and pan brake are really coming in handy here, especially when it comes to the double-fold on the door panel.

It's actually going to fit folded side out to the front of the plenum so that the flat panel sits up against the side of the filter, otherwise the air would just blow right around it through the gap.

And we can also see the rails in this picture that the filter will slide into.

Those rails get riveted to a set of corner panels, and a pair of braces goes lengthwise between them to support the filter and block the air from going around the edges.

And the whole assembly will look roughly like this.

But that's going to need a lot of rivets, so before we get there let's take a quick newt break.

And refreshed from that, I'll add the cross breaks to the panels. I had initially contemplated not adding them as some of the panels were slightly too large to fit into my brake diagonally, but in the end I decided to go for it and employed the other method for adding cross breaks: using a window screen roller.

Which works surprisingly well, all things considered.

Then, about a hundred rivets later, everything is secured together nicely.

Was it actually 100? I don't know, feel free to count up the stems and let me know.

I do still need to attach the door to the plenum. I already have the hinges and latches, but I want to get the weather stripping first so I can space things out correctly.