2. analog
  3. 177351-1662

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.

lewm
lewm OP
13,106 posts
 

I recently bought a second copy of the Cardas test LP. I’ve been using it for years to warm up cartridges that either need break in or have been out of use for long periods, which happens when you own 5 turntables and 2 systems. Anyway, the new copy was very badly warped right out of the sleeve. I of course immediately returned it to MICHAEL PERCY audio, and he replaced it immediately, no questions asked. Still, it is surprising to me that Cardas could let such a thing go out the door as a test LP, of all things.

juke4u's avatar
juke4u
50 posts
 

I have thousands of 45 RPM records. I got 2 1/4 inch thick pieces of glass made with the center cut out for the label. I put the 45 between the glass, taped the glass together, and sat it on top of light bulb. (about 6" from bulb) I would give it 30 minutes and take it off and let it cool. It only failed a few times on the very thin reproduction 45 records. It should work on an LP.

In my audio system I have a Sota vacuum turntable and must say it works great. Basis make one that work great also.

jazzguy43
39 posts
 

Friend,

No! No! No1 The physics will not work for you. Once a round object is warped it is really not round w/an eccentricity of 1.0! Nothing you do will ever bring the eccentricity back to 1.0! In essence you will now have an ellipse and your lp is not round. Watch the tonearm swing and make your lp sound on the weird side. Benn there, done that! Also, too much pressure w/heat = NO MORE GROOVEs!!!!

terry9
2,341 posts
 

Not so sure about that jazzguy.

Say:

1. a record is pressed as a perfect circle

2. then is warped, e.g. by heat or pressure, and assumes an elliptical shape with a warp

3. then heat and pressure could return it to a perfect circle without a warp.

Or am I missing something?

lewm OP
13,106 posts
 

I see Jazz guys’ point, if you assume that a warp represents a local stretching of the vinyl, such that there is excess material in the horizontal plane and this forces the warp to occur. Like pavement expansion on hot days. If we assume that that is the genesis of a warp, then it must also be true that the LP will have thinned out in the region of the warp in order to produce the aberration. I have never observed such a thing, and I have never stored any LP ever under conditions that could conceivably cause vinyl to “melt” and warp in that fashion. So this is my reasoning why I also doubt jazz guy’s thesis. But I don’t doubt he saw what he saw. Perhaps the occasional LP comes from its factory in that condition, the warp having been caused by uneven heating in the press. But don’t we assume that most warps occur while the LP is in our own hands, in our own house?

More to discover