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.


@drbond , I have never measure the distance off center. I am not sure what for. Just watch your tonearm with a reference nearby. You can see the tonearm tonearm drift back and forth at 33 times per minute. That record? I'd guess it was somewhere around 0.6 mm off. The standard is within 0.2 mm. 0.6 is huge. That means the arm will drift back and forth 1.2 mm. 

optimize, You make a good point and it shows good thinking, but I question whether what you say is true for all warped LPs, because in many cases the warp you observe is compensated for by several smaller less visible warps in the opposite direction.  Let's call it "upward" vs "downward" warps.  This is one reason why trying to get around the problem with a central clamp won't work for both sides of that LP. Thus the LP itself has not lost its basic dimensions; they are just distorted in vertical space.  That should be reparable when you heat and flatten.  I don't doubt your story regarding the one example. 

Yes, you are right that there is "different" types of warps and severity of them.

The point is to get a better understanding of the material and how it works/act and flattening is not always the end goal and the assumption that we are done and all is going to be back to how it were only if we get it flat.. when there is other things happening and getting worse as a by-product. That we don't concider and take into account that is good that we know of and take it into account. (Oh, this record is to much warped or have a type of warp that makes that individual record "unrepairable" so it can be played again.)

Yeh the server warped disc experience I described before were a great educational thing for me that made me think about what really happened and how it works. When you have bigger warps then it is easier to see the actual effects of the flattening process. When the effects also will be greater.

I went into the project with the mindset that only I straighten it up to flat then all will be good and restored back to its original shape/state as a goal. And did not concidered any other factors that were a mistake from my side that I learned from.

And I probably think that many others also focus on to get it flat and think that it will be 100% restored back to its former shape. (But for smaller warps no one will notice any change or degradation even if they are there.)

@lewm , the solution is simple. Get a turntable with vacuum clamping :-)))))

And, a record flattener. 

@lewm , if i understand your situation, you have a very  small percentage of your LP collection with warps that concern you, BUT , when played, you dont notice a mistracking or audible problem....may i ask why you why wish to attempt to remedy this?  If its not broken, dont fix it.. I have a few similar, as well, BUT also dont note mistracking or pitch has bothered me, but I just shrug my shoulders....