How best to eliminate LP warps

I own about 2500 LPs, and I like to think they're flat.  Furthermore, I espoused the view that warped LPs ought to be discarded.  But lately I have found 2 or 3 of my LPs that do have warps but sound too good and are too precious for the music recorded on them to throw away.  So I am in the market for ideas on how to remove warps.  I am aware that there was a device on the market that looked like a large waffle maker, to be used for warp removal.  I think Furutech made it, but I never see it advertised these days.  I am also aware of the DIY method of placing an LP between two glass plates and heating the ensemble.  The question there would be how hot and for how long?  Any suggestions are welcome, especially opinions on the efficacy of the Furutech.  Thanks.  Please no comments on vacuum hold down; I think it's a great idea but none of my five turntables has that feature.


So you’ve recently examined each and every one of your 2000 LPs, and you know for sure that only 5 have a detectable warp?

I doubt it. Actually I too had that smug attitude toward the issue, until recently I detected moderate to severe warps in 2 or 3 LPs I do not want to discard. Which led me to start this thread. But oddly and amazingly both of the LPs that were most warped actually played pretty well, and I did not detect any obvious distortion while watching the stylus trace up and down over the warp. I do not agree with Mijostyn’s hypothesis that this is because we are used to speed aberrations in the vinyl medium. I really don’t know exactly how to explain it. The stylus did not take off into the air. The tonearms were respectively my Triplanar and a Dynavector DV 505. In both cases using high compliance cartridges, so that may have something to do with the traceability. 

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.



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.


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.