On drums...

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Cliff

River City Trio

What if we did all have the same opinions?

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Cliff

River City Trio

What if we did all have the same opinions?

Cliff:

All rods have the relief (what I called the "step in"), regardless whether they have the barrel.

By measurement: Barreled rods 5.3mm across the relief, non-barrelled 5.0 across the relief, so the existing rods are better suited to my 12's problem, even though they don't answer it.

You are right on the threaded portion of the standard lug’s being longer (15mm above the lug body) than the ones on my 12 (10mm above the lug body).

I had not noticed that, but clearly the longer lug inserts would have allowed the tunesafe to clear the H bar, but that would have pushed the the insert and tunesafe almost up to the hoop. As the distance between the top of the insert and the hoop diminishes, the angle of offset between the placement of the insert and the hole in the rim (relative to the center of the drum) becomes effectively greater, and that angle seems to be what is pulling the lugs out of true. Thus, using the longer lug would, at the very least, make my offset problems greater even if it solved the problem of the H bar, a problem that is pretty low on my totem pole.

However, the offset leads to the question: how are these lugs designed to allow a certain amount of flexibility in offset, both to account for eccentricity of head mounting and/or to avoid cross threading?

I pulled the tunesafe cap off one of my 12” lugs, grabbed the threaded insert and tried to wiggle. Nothing. Even so, the hole through which it emerges from the lug body is wide enough to allow for some wiggle room, and the insert is pressed against the outside of that hole. That seems wrong. Repeating the same experiment with a lug on the 13, I was able to get considerable motion from the insert in all directions.

So clearly the insert is meant to have flexibility to account for the offset. Next step is to pull the 12 back apart to try to understand why at least some of the inserts are rigidly fixed. There is hope.

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Gregory

On second thought, why not just trade out the 13" inch shell, lugs, H bar and heads, and use it that way?

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Gregory

The lugs are composed of the body (two horizontal nodes with a vertical "tube" that joins them, a two part threaded rod receiver, and a length of hard plastic hose. The The two pieces of the receiver screw together after being introduced to each other at either side of the larger lug node. They tighten to each other but not to the lug body. The bore is wide enough so that the top end of the receiver has considerable room in which to move. The vertical tube allows the bottom of the receiver to tilt freely, and that is effectively the pivot on which the receiver moves. The final piece is a length of hard plastic tubing placed there so that the receiver cannot fall back into the lug when the rod is pulled out.

Pictures are more useful. The third photo merely demonstrates the bore through the lug:














Two of the twelve receivers were free moving in their lugs, the other ten were solid. The reason for that was that someone at the factory was very free with a thread locker. Not only were the threads of the receiver well doused, but so were the inside of the bores, the square brass receiver base, and the inside of the lug tube. In order to free the parts up, the lug was place lengthways across the open jaws of a vice and the receiver pressed partially into the lug (photo 1.) Then an 8mm open end wrench very carefully, back and forth like the motion used for cutting threads, unscrewing the outer receiver from its base (photo 2). Once I figured out the method, it was fairly easy going.

I don't have any thread locker delicate enough for the job, so I put it all back together without it, hoping that the tension and the remnant thread locker still in the threads will hold it. But how nice to have lugs that allow the receivers to accommodate necessary angles.

Now the issue of the overlapping tunesafes becomes more of a problem, although they will probably compress their offending rubber bushings on the H bar, but I think I will cut away where the tunesafes compress them. Then we'll see how this all goes back together.

Once again, I am bitter. Who gave some beer drinking lout the damn tube of Loktite?

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Gregory

Cliff suggested I use the lugs with the longer receiver from my 13 to solve the tunesafe and H bar rubber clearance problem.

I took four of those lugs and put them around the H bar of the 12. Yes, they do clear the H bar, but the top of the tunesafes now threaten contact with the rim of the head, one of them appearing to touch; I can't tell how much or what the consequence. The clearances are minute.

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Gregory

Grind the end towards the brass insert down by 1 - 1.5 mm?

It woiuld be so much nicer if this engineering had been done on the drawing board.

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Cliff

River City Trio

What if we did all have the same opinions?

That was my thought on both counts, but I didn't want to sound bitter.

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Gregory

The flares in the hoops now make sense; kinda like extended wheel well flares over fat tires. I've never thought of those flares as a good thing before now. Surely the problem should have been caught early on and the lug spacing and H bar rivets changed.

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Gregory

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Cliff

River City Trio

What if we did all have the same opinions?