This seems to make a certain sense but I don't understand how/why the plaster should develop high spots. If the plaster is expanding from absorbed water, I would think that the rate and amount of expansion would be fairly equal over its entire inner surface. I.e., all the plaster would be expanding, reducing the inner diameter equally. What other factors am I not taking into consideration? Gray spots may just be the result of the plaster contacting a less polished/more abrasive area of the nickel. If plating came off from rubbing against the plaster, the entire surface of the spirals should get gray where they contact the surface of the mandrel, right?
Ron L -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Peter Fraser Sent: Wednesday, April 26, 2006 10:27 AM To: Antique Phonograph List Subject: Re: [Phono-L] best reamers? No, actually, the best reamer is no reamer. The way to do it is to take a flat-edged table knife and scrape down the high spots. you can identify the high spots easily by noticing shiny gray places in the plaster, where the nickel of the mandrel has compressed and discolored the white plaster when you press the record onto the mandrel. see, scrape, fit, repeat. do it until the record fits far enough to play. it takes time, but this is why you should do that: a reamer gets those high spots, but also sands down the corresponding opposite spots. you end up with a perfectly round interior diameter, but one that is usually not concentric with the exterior diameter...and so the whole record orbits the axis of rotation eccentrically (that is, the playing surface rises and lowers relative to the mandrel's surface, with each rotation) and sounds awful...permanently! On Apr 25, 2006, at 6:52 PM, Ron L'Herault wrote: > I guess that in order to fit some cylinders onto the mandrel a > reamer is a > necessary evil. I believe they can be made differently also. So, > I'd like > to know which type of reamer people prefer and why. Since I am > going to buy > one, I'd also like to know who sells the type of reamer you prefer. > > Thanks, > > Ron L > > > _______________________________________________ > Phono-L mailing list > [email protected] > > Phono-L Archive > http://phono-l.oldcrank.org/archive/ > > Support Phono-L > http://www.cafepress.com/oldcrank _______________________________________________ Phono-L mailing list [email protected] Phono-L Archive http://phono-l.oldcrank.org/archive/ Support Phono-L http://www.cafepress.com/oldcrank
