flattening warps

[92135011]

please share some techniques

[DMK]

please share some techniques

But they don't cure bad warps. The best technique is to simply not have warped records! When that is not possible, there are some methods I've heard of but don't recall except check stereophile.com. I believe Fremer wrote about some type of outer clamping device that worked well. Also, I've heard that some people "cook" their warped vinyl in the oven between two pieces of glass. Yikes!

My best recommendation is that you post this on the vinyl asylum at audioasylum.com. I've never tried anything and I've only got two records that are unplayable at their beginnings due to warps. My second recommendation is that you attempt any method that has to do with heating the vinyl with extreme caution!

[92135011]

The stuff I got dont got mega warps but you can see the arm bobbing up and down slightly. Everything is playable, just that I heard that warps reduce the life of the stylus significantly, thats all

[trollgirl]

...a short piece about baking an LP in an oven. Have two square pieces of glass cut - the heavy stuff, polished plate - 13 inches square. CLEAN THEM! Sandwich the LP between the glass, and put in an oven (150 degrees?), and turn the overn off. Kind of like making yogurt... I've done yogurt this way, but not vinyl.

Laz

[skeptic]

You're scaring me!

[92135011]

You're scaring me!

huh...?

[skeptic]

Heating vinyl phonograph records is probably one of the most efficient ways to destroy them.

[skeptic]

Vinyl phonograph records depend on ultra precision indentations at a microscopic level in the groove walls in order to work. All materials, including vinyl plastic have an "elastic limit" a point beyond which further pressure causes permanent deformation. In other words, when you press on it, it doesn't bounce back to its original shape anymore. When you heat plastic, you are lowering the point of its elastic limit, making it softer and more pliable. This is what allows you to change the shape of it permanently removing the warp. But if it warm enough and the pressure is high enough to remove the warp, it is also high enough to damage the grooves. That's what's scary about it. This is why record manufacturers always recommended that you never store phonograph records in direct sunlight or near radiators or heat vents.

If there is an effective way to remove record warpage without damaging the record, I haven't found it in about 50 years. The only thing I can say is that if you use a turntable that applies a vacuum to the disc while it's turning, that should help. As soon as the vacuum is removed, the warp will return. A record clamp may help at least on one side depending on the nature of the warp and how badly it is warped. If it is "dished" slightly, it should help on the side that is high by forcing it down. If has a ripple near the edge, it may not help much.

If you try trollgirl's method, start with discs you don't care about losing incase they are damaged. Let us know how it works out.

[trollgirl]

...I should have mentioned trying it first on a throwaway LP. I ate my first batch of oven yogurt, however, and was undamaged.

Laz

[92135011]

Let's say I dont remove the warps
How much more will it wear out my stylus?
Assume the warp is minor and does not affect the rhythm.

[skeptic]

I don't think anybody here could even venture an educated guess. Even assuming the stylus never leaves the record surface, the answer would depend on many factors such as the tracking force, the geometry of the stylus, the compliance and material of the cantelever, and the exact nature of the warp. Why not contact the manufacturer's service department for advice.

[92135011]

Well I guess that I should call you Mr. Fantastic now
I wouldnt ask if I trusted a guess

[Woochifer]

The approach that I remember from when I was a kid was to stack a bunch of phone books on the record for a few days. I made unplayable records playable, but it certainly did not eliminate the warps.

As for the effect, I would guess that playing warped records is not good since even 2 grams of tracking force concentrated into a single needle point is a pretty big load for a record groove to handle, even under the best of conditions.

[jack70]

For small warps a clamp is the easiest solution, but they don't all work on all spindles... they need to be able to grip it and they're all built differently.

I wouldn't bother with the "cooking" crap... vinyl (plastic) is "set" when it cools from a liquid to a solid (the moleular structure). Certain formulations of vinyl might be "changable", a bit, but getting the exact temp and pressure to do that (consistently) would be impossible at home. You're much more likely to make it worse, if not ruin it completely.

I'd try an arm like an old Rabco (tangential/straight tracking arm), or a vestigil (Irish co). Although both are completely different beasts, but they are also both completely different than 95% of the "traditional pivot arms out there. They each have a radius of momentum that's only an inch or so, so they can track even a grossly warped record with no sweat. (Very neat to watch too). From a physics standpoint it's like using a warmup-baseball bat that has 10 pounds of lead in it, versus a very thin light bat, which is just much more responsive to quick movements.