How Do Records Know Which Side To Warp

Regarding dish warps, how do records know? More music content on one side weakens/strengthens that side's vinyl? Or is it a Side A/Side B thing? At the expense of family, friends and earning a livelihood, I've spent years pondering this question. Any thoughts appreciated.

 

Good question for Steve, maybe he knows.

Dish warps are the least likely kind of warpage you'll ever encounter...I've only run into a few.....it's a strange phenomenon, you have to think it happens somewhere in the pressing plant, rather than most warps that happen in storage after the records have been shipped.



ED

 

(Thinking aloud) It probably has to do with one side cooling down faster than the other after pressing, for some reason.

Think of two identical pieces of something flexible stuck together; to get them to curve to one side or the other, you need one of them to contract or expand.

Either that or maybe the pulling off the press has something to do with it?

 

Someone told me it happens when they stack too many records during production before they get sleeved. Donno if that's true...

 

From not-so-scientific observation, I've noted that cold affects vinyl in strange ways, many times resulting in a dish warp. Most of the time they snap back to attention, but not always. But why one side rather than the other? So far, I think Gary best addresses that phenomenon.

 

If you get a table with a clamp, such as VPI or many others, you will probably not think about warps again. I had non-clamped tables all my life and always had trouble with warps. I got a VPI table a few years back and now don't even think about warps. All records just clamp down flat unless there is a real severe speed-bump type of warp, in which case I don't want my cartridge on it anyway.

Now, off center pressings are another matter altogether...

 

Tight shrink wrap can cause some vinyl to dish warp, but the true answer may be more complex. I think what you're asking may be two-fold:
1. How do some LPs arrive dish-warped. (Think 'RCA Dynaflex'.)
2. Is it possible for vinyl to dish-warp while on your shelf at home?
(Quite unusual. Maybe if you store them horizontally.)
And, if you got one, how do you safely play it?
An LP disc clamp will hold the convex side flat -- but how about the concave saucer side? It always looks horrible, and just think about the tracking!

 

It's whichever side faces the side of the cover with more black ink. As we all know, like colors attract (unlike magnets), so a blacker sleeve design on one side of the jacket will cause the outer edges of the album (away from the non-black label) to move toward the black sleeve, creating a dish warp. Simple chromatic physics.

Now, colored vinyl is a different story altogether...

Ryan

 

Wow, "chromatic physics." I *knew* it had to be something like that.