Well I feel foolish! I cut another circle for the bottom, marked the 3 1/2", eased the circle as it went along, and it ended perfectly! No excess, no problems.
So why did I have so much trouble with the top piece? Here's the perfect bottom, and how I pressed the edges.
Now for the inside. I cut a piece of foam board (cardboard or mat) to fit in the bottom, and a piece of Mylar (plastic sheet) that is 1 1/2 times around the outside and 1/8" shorter than the height. I stuck my hand in to pull the seam allowance up so the board sits flat on the bottom.
Double sided tape would have helped because it was moving around a bit. I rolled the Mylar, inserted, and it unrolled itself to fit the inside. Pushed down on it, and then added a piece of quilt batting at the bottom, hoping it would keep the filling from wandering. I used those little plastic beads because I've had them for years and want rid of them.
I stopped 3/4 way up the tube, and smooshed them down, tapping lightly to settle. When I pressed on the beads, they expanded the Mylar to the limit and made a firm drum. The reason for cutting the Mylar much bigger than the drum is to have an overlap inside to keep the filling from getting behind it.
Added another layer of quilt batting over the beads. Next will be several inches of crushed walnut shells for the pins if it would be used as a pincushion.
Then gather the muslin over the walnut shells, secure, and trim excess. A single layer of thin quilt batting to cover the muslin, and then hand sew the lined top to the drum. Maybe tonight! Maybe not. For a shorter drum, I don't know if I would use the same method inside. This is tall and I want it to sit well. Using all sawdust would make an excellent drum and I'll see how stable this is before the final stitches. If it's not, I'll try the sawdust. I'm just glad it worked out because I really like this finish for a sampler I thought I wouldn't like. All that's left is the little bit of hand sewing.
This wonky bird is on an antique wallet that I saw on Pinterest. Still need to show you Ann's, (who has piqued my interest in wallets) work . So for the next drum, will I machine sew the top and use the muslin on the bottom? Probably. But I will keep this drum finish in mind for short and wide samplers like this one. I think using the Mylar and bottom disc would allow a much bigger round but shorter drum, too. Theresa gave me a great idea to use wool or wool felt for the circle, which doesn't ravel. Just press or tuck the drum's top edge, and hand sew a wool top to close. Thanks Theresa!
Thanks for visiting!
Hope I didn't bore you with this!