Getting a bent Acro back into perfect round?

bongomania

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Short version:
I have an Acro that I suspect is out of round. How do I get it back into perfect shape?

Long version:
I recently picked up a Blacro in a trade; I knew about a couple of small dents in it, but otherwise it seemed good. Upon receiving it I noticed that the P85 was bent out of shape. This morning I replaced it with a P86, and noticed that the contact points of the shell where the throwoff attaches were also dented-in a bit. Then I installed a new snare side head with normal even-all-around tightening, and used a Drumdial to check. Two of the lugs were WAY off, way lower in tension than the rest. If most of them were around 80, the two bad ones were around 70. Second-guessing my earlier tightening, I went ahead and torqued them down until they read around 80, but that resulted in the lug bolts bottoming out, and the rim being level with the bearing edge just in that area. I undid that, and bent the rim back into flat level, and with some finagling I've managed to get it so most of the lugs are a few points above 80, and those two are just a bit below 80. Should be usable for a snare side. The top head and rim seem fine so far.

Can this be fixed, by me or anyone else? I live right near Revival Drums, so they probably have a guy who can work on this sort of thing, but what will HE do?
Thanks!
 

69OysterBlue

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I have seen a tool used that has two arced pieces on either end that mate of to the inner diameter of a 14" snare that are connected by a rod that has a turnbuckle connection in the middle.

By cranking the turnbuckle, a significant but very measured pressure can be applied to the inside of the drum to get it to expand where it is out of round.

I am sure there is still a lot of technique involved in getting this to work properly, but it looked like a great solution.
 

Coco Nabes

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I got my Acro shell back into round by measuring the shell to figure our the widest spots across from each other then lean on it on a carpeted floor. Did this on both bearing edges. My shell was out of round about 3/8th of an inch and it took me all of 10 minutes to get it back into round.
 

Randy73

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Coco has it! I have done this on a few COB shells. Just do minimal amounts at at time and measure across from lug to lug at all 8 or 10 lugs until the diameter at all points match. I would remove all the lugs and use a small block of wood along with a rubber mallet to straighten the dents out while you're at it.
 

theneonguy

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You're right, Coco. It IS like performing CPR. And in the end, the life you save is a great old Acro.
 

bongomania

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Success! I followed your advice, just using light-to-moderate arm strength (not even leaning on it) and was able to get it so it measured exactly the same across all lugs on both sides. I used a new reso head just to be sure, and voila! It tuned up great, with no issues. I also rubber-malleted out the dings.

Thanks guys!
 

RIDDIM

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The same logic applies to older Ludwig stainless steel toms, which tend to be out of round from having been schlepped around caseless in the 70's, sans the bottom heads. Once they are back in round though, they are amazing. Fat yet cutting, even with coated single ply heads.
 

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