How to tell if the record is worn out?


Hi
On my recent trip to WFMU annual record show i encountered a problem that i've never dealt with before.Out of 50 records that i bought there 30 turned out to be worn out to a point where you can't even listen to them.Visually they look perfect though as if someone carefully played them from the beginnig to the end a 1000 times on a bad turntable,not a single scratch or fingerprint.I don't know if i's just a bad luck or since the show became annual instead of twice a year maybe many dealers do not care about returning customers any more?Is there any way to tell if a record is in bad condition?Maybe i should bring a big magnifying glass with me next time,the problem is:i don't know what to look for.Any opinions on this one?
overhang
Unfortunately, it is not possible to visually inspect a record and tell whether it's going to be ok. Making the problem worse is the fact that there are dealers at shows that cosmetically treat their records to make them look perfect. I'm not sure how they do it (perhaps someone else can chime in with an opinion on this), but the records look absolutely fabulous. In fact, they look too good to be true, and you know what they say about that. If I'm buying at a show, I'd actually rather buy a record that looks less than pristine, or a record that has not actually been cleaned as I don't really know what someone has done to clean that record. If they've manually cleaned and not vacuumed the record, there is a very high possiblity that all they've done is solidify a bunch of crap in the grooves so that even I can't get it out with an effective wet cleaning and vacuum.

On the other hand, there are many records that don't look particularly great that clean up remarkably well. The upshot of this is that I do the bulk of my used record buying at places that offer very cheap prices (read 50 cents to a buck or two max) and for more expensive fare stick to dealers that offer a return privelege if the record is not up to standards. Shows are a crapshoot.
I went to the WFMU show last year (during My Year in New York - book soon!) and bought 30 or so LPs. Only one was truly unlistenable - the rest cleaned up fine and sounded great. I'm not a high dollar record guy, so the most I paid was $6 for a nice copy of Lark's Tongue in Aspic. None of the records had been cleaned prior, and that was true for all the bins I was looking through. Very few were obviously junk, either, so clearly there had been at least a little prescreening.

That said, I think Hdm may be on to something. I watched a lot of people pulling $50 and $100 LPs out of the sleeve and they looked like black mirrors, way shinier than any new album I've seen. It was almost as if they were waxed or Armor-Alled. Since these were all used albums, it made me pretty suspicious, but people were buying them.

Like Hdm, I mostly stick to the 99 cent stuff at Goodwill and the closeout bins at used record stores. If one of those turns out truly bad, I just donate it back; they need the money, and maybe someone else will enjoy it more than I could.

Overhang, if you live in the NY/NJ area and haven't been to Princeton Record Exchange, it's well worth the trip. Great selection, fair prices, no waxing!
I am afraid that these practices have spread to Ebay. I have seen several records that show up looking good. They have been cleaned and possibly shined up. They play dead...heavy surface noise and terrible distortion. These records often have long, detailed and flowery descriptions. I do not like buying cleaned records!