Help with fixing a weird record warp?

[JHolmesesq]

I was playing one of my favourite early Bing Crosby records today, when the record kept jumping. I was a bit surprised because this had never happened to me before (but my old deck was a piece of crap so must have been vey light on the tracking weight).

It's a weird lump in the record - the rest of it is fine and in E quality which is a shame really. Does anyone know a way of salvaging an otherwise playable song?

This is the only photo I could find to roughly illustrate the problem

[Henry]

In vinyl, warps like this dish warp, or edge warps, can usually be fixed by flattening the record between two sheets of ¼"-thick plate glass, in the presence of gentle heat. Years ago, after reading about this method in Stereo Review, I had a local glass place cut me two sheets of ¼" glass, 13" square, with edges smoothed and slightly rounded. Make a sandwich using the glass as the "bread" and the record as the filling, and place in an oven that has been briefly (say, one minute) heated on the warm setting and then shut off. The idea is that gentle heat applied to the record under pressure will flatten it. Make sure the record is very clean, or any schmutz will be permanently embedded in its surfaces. Leave the sandwich in the warmed oven until everything cools down to room temperature, maybe several hours. Repeat as necessary, but don't turn on oven heat with the sandwich inside; start over from scratch (no pun intended!). Do NOT be tempted to speed the process by heating the oven beyond the warm setting, or you risk distorting the record and rendering it unplayable. Some guys put the sandwich in sunlight as a heat source, but I don't recommend this as you can't readily control the temperature of the sun!

Although I've not tried this method on "shellac" records, it would probably work on those as well. Comments welcomed!

[syncopeter]

Actually using the sun is quite a good idea. On a beautiful spring day like today just do everything mentioned in the previous posts, leave your record in the sun for some time (no more than 30 minutes), watching it carefully, and when the bump has disappeared take the assembly inside and let it cool naturally. You will most probably be left with some audible remains, but at least the record should track properly. I would never heat shellac to more than 60C because then you may end up with a blank.
A good friend of mine has used this practice for over 40 years without ever ruining one record.
Vinyl tends to flop into warp mode even after careful flattening. Records that had been stored correctly for ages and looked perfectly flat developed waves within seconds after I retrieved them from their sleeves.

[gramophoneshane]

I use the sun as well, and use the time exposed as a temperature control. I dont think I've ever had to expose a 78 for more than 5-10 mins though
I would like to get a hole cut a little larger than a label in my top sheet of glass oneday (or both sheels etched), so records with raised label (like is often the case with vinyl) can be flattened a little better.

[gramophoneshane]

BTWJ, what record label is that?
It kind of looks like Regal-Zono, but I've never seen Bing on an RZ before.

[beaumonde]

Jonathan, if that is a laminated "Potato Head" record (as I can sort of glean from your photo), I'm afraid there is precious little to be done. These might crack (lam crack) if you try to de-warp in the usual way (between sheets of plate glass in a barely warm oven).

Let me know which one it is; I may have a copy I can dub for you at least.

[gramophoneshane]

Jonathan, if that is a laminated "Potato Head" record (as I can sort of glean from your photo), I'm afraid there is precious little to be done.

Ah, so it is. I was trying to think what coloured label Bing would be on & completely forgot all about the potato hrad Columbias
I might just have been lucky, but I've never had lam cracks appear due to flattening a disc, unless they were already visible before I took out the warp.

[JHolmesesq]

There aren't any lamination cracks, and it is a Potato Head Columbia, it's "Reachin for Someone" that the main warp problems are.

Out of interest, what could cause a strange warp in just one part of the record?

[Henry]

There aren't any lamination cracks, and it is a Potato Head Columbia, it's "Reachin for Someone" that the main warp problems are.

Out of interest, what could cause a strange warp in just one part of the record?

Just a guess, but there could have been moisture and then shrinkage in the base material (whatever it is---some kind of pressed fibre board or composite substance, maybe?) as it dried. Since there's more material around the circumference than in the center, the shrink forces would have affected the edges more than the center, pulling (or pushing, if you will) it up into the dish shape. Pure conjecture, mind you!

[beaumonde]

I'm sorry, I don't have that one, Jonathan, but try out this one!

Col 1862-D

I'm In Seventh Heaven (with a great Bix solo) 148183-3; 4-5-29: http://www.box.net/shared/duc2aoagor

S'posin (with Bing) 148544-3; 5-16-29: http://www.box.net/shared/xgpdaxoepu