This is very interesting indeed. I have Slingerland orphans dating from the early 60's all the way to a 5 ply with no re-rings. The bearing edges tend to follow your examples. It would be interesting to know how these were made. I am assuming that the full round over required some amount of hand sanding to form but would love to hear more.

I think an interesting question to ask might be the following:

Did edges change to accommodate evolving amplified musical styles or did they change to accommodate quicker manufacturing techniques. While not being a woodworker I have to figure it is far quicker and expedient to create a double 45 bearing edge than a full round over. Any thoughts?

I've been unable to find a 9x13 Slingerland from the no badge, mahogany/poplar/mahogany shell period that has the classic round-over bearing edge. They all seem to have the rounded outer edge with the 30 degree inner cut.

Also, the 1962 Leedy/Slingerland kit I picked up has the the same rounded outer edge with the 30 degree inner cut on all three shells (14x18/14x14/8x12). Not something I've seen on other Leedy/Slingerland shells.

i have an orphan kit, but all of the drums are 3-ply late 70's.

the 22" bass drum batter is a standard large radius roundover with a 30 degree chamfer. The reso side has the same 30 degree chamfer, but a very steep roundover - similar to DW's ESE edge.

The 16" floor tom has very flat, fully rounded edges (no chamfer cut).

The 13" tom has the flat, fully rounded edge on the batter side, and a 30 degree chamfer with a roundover on the reso side.

I think this kit hits all of their edges, except the 45 degree edge from the 5-ply drums.

that is how they did the edges on their budget/student drums. the pro models had the flanged edges.

Thanks, jwsedens.

I've got a question about this. The Slingerland kit I just finished up had some really mangled up edges. So bad that I wasn't sure what the outer radius was. I guessed 1/8" which is what I used when I recut them. Some of these pics make the outer radius look larger than 1/8". Anyone know what size if any was standard??

Steve