Anyway, I have samples of Olefin coming from a mill here in North Carolina. It is somewhat less expensive than Sunbrella and has Double-rub values of 50k, 75k and 100k. The outdoor specific versions meant to compete with Sunbrella claim higher light fastness rating of 3000 hours and a 5 year warranty. https://revolutionfabrics.com/collectio ... oor-fabric
Starscream pointed out that making the outer covering tighter than the foam improved the fit. Glad he mentioned it, I'd have cut the foam and shell for the same dimensions. Isn't it great, letting someone else be the guinea pig.Starscream wrote: ↑Wed Jan 20, 2021 9:57 am Oh, and an additional recommendation for sewing cusions: make the boxing just slightly smaller than the foam height, for a good tight fit. Otherwise the smallest imperfections in the foam cutting show up as loose areas that need to be padding. I found that allowing for a 1/2" seam when cutting the panels but sewing a 5/8" seam gave a reasonable tightness to the covers.
I took out the foam and let it re-expand overnight.
The dimensions of foam are: 24" x 25" x 5".
The density of the foam is: 1.6 pounds / cu-ft
Apparently according to The Foam Factory, cushions should be about 2.5 lbs/cu-ft, but they also emphasized that thickness matters and their number was for thin cushions (2" to 3" thick). When using thicker, you can go softer and still not give up longevity. My Mac's foam seems fine and where I can, I'll re-use it.
Measuring the vinyl covering for the same cushion:
I measured top, bottom and both sides for each measurement and good thing I did, they weren't very consistent.
Width: 22", 22", 22.4", 23"
Length: 24.5", 24", 23.5", 24"
Thickness: 4", 4", 4", 4.5"

