How best to eliminate LP warps

@tablejockey 

What’s surprising is how resilient the LP is.

 

Amazing the LP grooves maintain integrity with all the deformation(is that even a word?) going on.

No it is actually not, a wrapped record is stretched but all is depending on how bad the warp is.

The diameter of the grove to the other it is not changed but it is a longer path from for example a stylus at a point the shortest path is the other side of a Hill is a straight line trough it as if it were flat.. but instead the stylus need to travel all the way upp the hill/wrap and down again to the other side.

So the stylus is traveling a LONGER DISTANCE than what it should have been doing when/if the record were flat. But the diameter is still the same.

OK then we have a STRETCHED and longer track then when it were flat (speed variation).

So when we flat out that material the extra length is not shrinking or get shorter back to its original size. The record will again get a new shape..

It will get flat but the additional length in combination that the material has no memory to get back to a previous shape. Where will that extra grove length go?

It will go to the side when we force it by pressure on a flat surface it can not escape somewhere else when it will not shrink.. to the side there is no pressure. 😜

So now we got the extra length on a flat surface so were the warp were it has gone to the side instead and now the third shape we have is that the grove is not circular it is more egg shaped! And do you look att the canteliver/cartridge NOW from the front you will see it work much more side to side (left and right). 

So we have changed from that the cartridge going up and down with the warp to left and right instead.. that is why a wrapped record is in reversible damaged forever. The goal should be to get the record back to its first shape as it comes out from the record press and that goal can we never achieve. Yes we can get the record flat but what does that help us when the circumstances of the grooves are longer than it had when it left the record manufacturers pressing..

Note that of course this is most noticible and easier to see and experience the more warped the record is. And smaller warps you might not be able to notice this at all.. when it is on a much smaller scale.

I think the premise behind flattening the LP by heat and pressure is the hope that the LP WILL return to its original flat shape, that the stretching represented by a warp, if it is indeed stretching, will be eliminated by a corresponding shrinkage. I must say I don't quite understand your argument that warps can never be "repaired".  Anyway, when you play a warp, the warp itself does represent a longer distance between points A and B on the adjacent flat surfaces on the LP, as you say, and because the turntable motor maintains a constant angular velocity in the plane of the platter, the velocity of the stylus in the angular direction will increase momentarily between the flat points A and B, as it has to climb and descend a hill.  That ought to cause a pitch change.  Possibly, because this distortion occurs amidst musical passages, which are complex both in pitch and timing, perhaps that is why we may not hear a problem.  The video that Mijostyn put up here on this forum, when we were discussing tonearm design clearly does show that if the LP is encoding a pure tone, e.g., 1000Hz in the case of the video about the ARXA turntable and its wonderfulness, you CAN hear the warp.

@baylinor 

If I insulted you I'm sorry but I was hoping you got my joke.  The icon/photo you have on the upper left corner of your posts is the cover of David Bowie's "Aladdin Sane."  I'm willing to bet that Bowie came up with the title as a play on words for the phrase "A lad insane." In any event, Aladdin Sane may be my favorite rock album. My intention was to raise a toast to your good taste.

That one went right over the top of my head lol. Was wondering what you were referring to. The lad made me think you were english.  Thanks for the explanation, it restores my view of humanity 🙂

"No it is actually not, a wrapped record is stretched but all is depending on how bad the warp is"

optimize-

yes, that's what I envision what's physically happening. I'm thinking a  simple flattening during playback thru a VPI type outer weight makes more sense to preserve the LP, rather than any heating and prseeing/flattening of the disc?

Perhaps once an LP is warped, any attempts at straightening are technically(maybe not audible) compromising integrity of the groove? 

Because I'm a period press fan, I've got more than a few great albums, but they're real zingers-like a mogul ski run for the cartridge.