How best to eliminate LP warps

I tried a friend's Vinyl Flat, but could not make it work for me. Too impatient, I think.

What did work is something very like a vacuum hold-down, a 'reflex clamp', which consists of a small flat dome under the label and a clamp that exerts force from the spindle. Actually I used the dome and a 2-3 kg weight, which is no problem for my air bearing TT. This solution is discussed on DIYAUDIO, the DIY Linear Tonearm thread, Niffy's posts on page 143.

Works well for me, and even improves the sound of flat records!

lewm:

What about glass panes and an electric blanket @ moderate heat?

Tried the glass/oven procedure once and it made the "edge" warp worse.

DeKay

As my brain continues to de-fog (thanks all you guys!), I now remember doing A-B comparisons between having the SOTA vacuum hold down on & off. Vacuum hold down gave me more weight and dynamics but I often preferred the lighter, airier sound of just letting the LP lie there on top of the platter. . Imaging was different between hold-down and non-hold-down but were equally satisfying. A screw-down clamp meantime, puts me halfway between with the best of both worlds. In any case, a screw-down clamp is the way I now almost always go.

Thanks, guys.  I think we've covered the waterfront when it comes to curing warps. Unless someone else has a treatment not already mentioned.  My preference is to reduce the magnitude of the warp before playing the defective LP.  I am less interested in clamps and vacuum hold down, in this instance.

Clearaudio outer ring. Wayne’s audio outer ring. Vpi outer ring. Add any center weight.