CORRECT WARPED VINYL LP RECORDS and 78 rpm Shellac Discs - HOW TO

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hobbyists's views for hobbyists
Is There An Easy Way To Correct Warped Records?

How to Prevent and Correct Warps in LPs.

In the olden days of thick flat mono records, warps were brought about through mishandling a record by the owner.
In the 1970's less vinyl was used. Warps were easily made and generally already made in the factory just after the record had been pressed.

The employee in the pressing plant would lift the fresh pressed record with the index fingers of left and right hand off the matrix before it was sufficiently cooled down. This was especially the case when thousends of records had to be pressed in a short time. On those records there were generally two warps. In modern factories the pressing process is more automated.

Those warps will generally not be corrected or you will have difficulty correcting them because vinyl has a memory. However most warps you will encounter are the result of temporarily exposing a record to a heat source, be it the central heating or the sunshine. If the room temperature is rather high and the records are laying about or not stored with care, one or more light warps can be the result. Warps can gradually manifest themselves ober time when records are packed in a box with too much room.

It is difficult to correct warps. The method with glass plates does seldom work to satisfaction; in my experience it never works! The main reason is that the vinyl is clamped in between the heavy glass plates and a gradual flattening over time will be obstructed by the heavy glass plates which do not allow the vinyl to move/expand/stretch/relax. The only effective method to correct warps is to use a special component like Clearaudio's Vinyl Doctor or a similar device. The vinyl record is put into the device, slowly heated to a safe temperature and then it is cooled down over several hours. But such a machine is rather costly and only pays off if tyou have too many warped records.

Light warps of thin records can generally be corrected on the turntable during play using a peripheral record ring. But after the recxord has been played, the warp just stays. To correct more severe warps in heavy records a heavier ring must be used. But then correction is not always possible, anyway in my experience as I have both a light weight peripheral ring and a heavy metal ring as well.

So what to do with warped records? First let's have a look at those in a box. Examine what sort of warp you deal with. Is there a curve at the perephery at one spot caused by sagging or does the record have the shape of a dish? First of all get rid of the soft plastic foam. Plastic foam was maybe right at the time of production, but after so many years it certainly has deteriorated and has lost its elasticity. If there is a cardboard filler, it should be sturdy and completely flat. If it is not, throw it away as well or keep it but outside the box.

Now measure the size of the compartment: height and width.

Cut out squares of thick cardboard and make sure that they fit exactly in the box.

Cut off one small corner so you will be able to take out the cardboard filler easily if necessary.

Use the cardboard sheet as a replacement of whatever filler there was in the box before. See to it that the cardboard is flat and sturdy. You can choose the thicknes in relation to the room you want to fill up. In the picture at right you see ordinary cardboard. If you want you can buy a nicer material in the art supply shop. But it should always be completely flat and have no tendency to bend easily.

Put the records in the box. See to it that there is no room left for sagging. If there is room left it is necessary to put an extra square sheet of cardboard on top of the records before adding the documents. Hopefully the documents have the size of a record and are not the smaller booklets often provided by EMI in Great Britain. Then close the box and store it vertically. This will prevent warping and will help correcting light warps over time. As a matter of fact in this way time is your aid.

So if you encounter a box containing warped or concave records, do not throw these away. Just fill up the empty space and make sure that there is no room left when the box is closed! A tight fit is necessay. Store the box on the shelve so that it is supported on both sides by other boxes and records. It is better to store records and boxes rather tightly instead of loose. You may discover that after a month or two the records will have flattened. It goes without saying that the records should be cleaned or at least dusted off with a carbon fiber record brush, and that the paper sleeves should be free of dust particals.

This method will also work with individual records. If you have an empty box, you can follow the method described above. Take the records out of the outer covers and place them in between cardboard sheets. If you do not have a box at your disposal place the records as shown in the drawing and keep them tightly stored for a couple of months. This method works only with vinyl from the 1970s and 1980s. Give it a try. And if it does not work you always can take more drastic measures.

I bought a box with the complete chamber music of Johannes Brahms. The records were hollow like soucers. I did put several sheets of cardboard in the box. And guess what after 2 months the records were flat again. And it also worked with Mozart's Violin Music played by Henryk Szeryng and Ingrid Haebler.

Prevent and Correct Warps in 78 rpm Shellac Records.

The same goes for warped 78 rpm shellac records. For single discs in individual sleeves as well as for albums. Albums can have to much room (seperation) between the subsequent kraft sleeves.

Use sturdy cardboard which is completely flat. Cut out square sheets measuring the size of the paper sleeves of the album.

Insert these cardboard sheets between all discs as shown in the picture.

This is how it should look like. Now store the album vertically on the shelf in a tight way so that sagging is not possible. You will see that after several months the records gradually have been flattened.

It is easier to correct 12 inch discs than 10 inch discs. I used this method for a Deutsche Grammophon box with concave vinyls. And I used it for the Cortot-Thibaud-Casals album shown above. In both cases with good results. I hope that this method is also valid for your warped records and that it will improve your collection and your listening pleasure. That is to say if you have patience.

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