My answer is BOTH!
I use different foam balls based on the type of ornament pattern I’m doing.
For these, I tend to use the rough Styrofoam. Why? Well, there are several reasons.
- I find it about a zillion times easier to push pins into than the smooth foam. This isn’t a big deal when you only have to stick in a few pins. But when you will be using several hundred pins, this quickly becomes an issue. This will especially be an issue on those last couple of layers of the ornament, when you are pinning through several layers of fabric… and even more especially an issue if you are using a heavier weight fabric.
- I have personally found that the smooth foam easily dents when pushing pins through the last few layers of the ornament, especially with heavier fabrics. It just doesn’t “give” as easily as the rough foam, and so if you find yourself pinning through heavier fabric and really needing to give it a little extra push to get it through the layers, the smooth foam just pushes in with the pin, right under your thumb. (This is not to say that the rough foam doesn’t dent…it does. But…since it is easier to push a pin into in the first place, you won’t have to push as hard, and therefore you’ll avoid the dents.
The rough foam is a little bit cheaper. – This is not so much the case any longer!
A few people have said they used the smooth foam for the regular quilted ornaments because they were afraid that the roughness of the regular foam might be able to be felt though the fabric of the finished ornament. Nope, this will NOT happen on that style of ornament.
Since the ornament is made by folding pieces of fabric or ribbon and then layering them on top of each other, the roughness of the Styrofoam base is completely masked by the time the ornament is finished.
Snow Globe Quilted Ornaments & Kimekomi Ornaments:
So…. even in light of everything I listed above, I still use smooth foam (polystyrene) too, and I even recommend it in my Moonlight ornament pattern, as well as for Snow Globe ornaments, and lots of other crafts and other ornaments that you’ll find on this website.
That’s because these ornaments have fabric that lies directly on the ball, in a single layer – no folds or layers to provide barrier from the foam below.
So, for these, smooth foam works best, because the fabric lies nicely on the ball, with no roughness from the ball showing through.
By the way…