The Vinyl Flat and Groovy Pouch has worked great for me. I got one for my birthday in March of this year. Every warped record that I've tried to flatten came out nearly 100% flat. I first preheat the Vinyl Flat in the Pouch to 130-140F. Then I put the LP in the Pouch at medium temperature and monitor the temperature to keep it 130-140F. After 2 hours, I unplug the Pouch and let the Vinyl Flat cool while still in the Pouch for another 2 hours. Every record, both brand new and used ones from the 70s and 80s have come out flat.
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.