I'm assuming by "bump" the OP means something like this. This is my 65 JF. The edges were all over the place so I had them tidied up. This is the before shot.

My bad, I thought the guy was talking about the bump caused by inserting the wrap into the plies on the side of the drum. I was providing information relating to the bearing edges as a separate issue, the 'Ludwig bump' (along the seam-side of the shell) is nothing to worry about. If the edges are off, they need re-doing. Sorry if I created any confusion.

John

Actually, I'm sorry for confusing you with someone who *doesn't* know all that stuff I said about edges in my last post. Somehow I switched gears to general blathering while continuing to address you...lol!

I'll try not to do that again. :)

Mitch

Mitch - I didn't take it that way at all and 'good information' is never 'blather.' Especially not to anyone who is reading/hearing it for the first time. I got the OP's post bass ackwards, I thought he was talking about sanding down the seam bump. Your dissertation on bearing edges was completely appropriate. And don't ever worry about offending me... we're buds, I never interpret anything that comes from you in a negative way. I just don't ever read you that way.

John

I'm with Purdie one this if the shell in question looks like the crop of the gold sparkle one. The factories were often faced with production issues due to changing employees, trainees, and output demands from the front office.

If a shell slipped through QC from time to time, that isn't something to preserve. QC would have sent it back to the shop if they'd caught it. Consider Buddy Rich, as one example of a guy that understood this. He had Eames restore his older Slingerland kit. You can bet your bottom dollar they dealt with any issues that kit had in the bearing department.

I have a beautiful Rogers Citadel from 1969. Second one I've had with edge issues. This one is 22,13,16 and the edges on the 13 were an abomination. Same for the 12 on the smaller 20,12,14 kit I had. Otherwise, they were beautiful shells. This time I had Heuer Labs in LA correct them per recommendation from Idrum4fun. Excellent recommendation! Heuer trued and finished them like they are custom Dynasonic edges. I could not detect so much as a millimeter change in shell length either and was really surprised. He buffed what was already nice wrap, and the were returned to me looking like factory-new. Couldn't be happier and I believe it was the right thing to do.

If you have some remarkably rare drum or one owned by some famous person, perhaps you'd hold it in that condition. However, if you're going to play, it needs to be corrected if it's that distorted.

I thought the same thing as Purdie,..The famous Bump on the seam, and Purdie is correct, you would go through the top plies before you can level the bump.

This one looks like router table issues.

But how many times have we invented the flat surface, sandpaper turning around twisty thingy ? But it works. Shortens the length but you can`t really add on the edges.

Question:

Does the longest distance in length go over or is it under the tolerance of the shell depth ?

If it is longer, flat table sandpaper time !i

If it`s shorter, your tension rods may need adjusting too, but there is play.

Coolio, high-five, onwards and upwards...:)

Now where the heck is Chromeo? :)

Mitch

I have never heard that tip before. That is brilliant!

This is funny as my Ludwig Rocker snare I was just working on actually rocked too!

Only rocked on the resonant side though, and I could clearly see that is how Ludwig made the shell for the snare and wires on this particular drum!

Great tips as usual guys! :)