Don't want to buy foam brushes because they're usually junk… especially the cheap one's. And your probably going to throw it out after one use anyway…

Here's the answer…

An inexpensive DIY foam applicator/handle.
You'll be able to get 12 foam applicators/brushes from the pack like in the photograph (6 sponges cut in half) for $1 (well a $1.25 now :/).

Easy to print and assemble.
Requires two #8 x ¾" (19mm) flat head sheet metal screws (the ones in the photo are also self tapping, but not necessary). Not sure if wood screws will work as they have a different profile.

Print in the orientation as provided.
At 0.2mm layers… suggest (a least) 4 walls and 8 top/bottom layers and 25% infill. I personally like triangle infill. For practical prints at 0.2 layer height, I always just double the wall count for the top/bottom layers.
The only material I'd suggest NOT using is any Silk PLA since the layer bonding is so weak.
I used Inland (brand) PLA Pro (same as Polymaker Polylite PLA Pro) for this project and it worked great.

After assembly the foam can be shaped (with a sharp razor knife) to any profile you need.
Works great for paints, stains, glue, oils… anything as long as it's not going to eat the sponge or plastic.

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