In a message dated 1/26/04 11:41:16 AM Pacific Standard Time, [EMAIL PROTECTED] writes:
> A local university tagged it for disposal, not because it didn't work > but because it was old (according to my friend who scavenged it for > me *before* it was hurled into a dumpster). You're right, Barry, that > there might be someone there who would still know how to operate it. > But I doubt anyone would know how to calibrate it as there is a > sticker inside that says that Mettler last did this for them in 1995. > After I learn how to calibrate it I hope it'll be easy to figure out > how to operate it. Thanks! Maud > I have one of the wonderful Mettler balances. The instruction manual is not especially helpful for calibration. It is a starting point, but you have to learn what to do yourself. Thereafter, it is no problem. You need a precise, one-gram weight. I wasn't satisfied with the brass weights sold commercially so I went to a jewelry supply store and bought one gram of platinum. This won't oxidize and is as close to one true gram as is possible. Yes, you can use one milliliter of distilled water, too, but it won't necessarily be reproducible. I keep the weight in a glass vial inside the top compartment of the balance and handle it only with tongs. There are two adjustments on the balance: zero and span. You have to zero the balance unloaded, then add the weight and adjust the span to 1.0000 gram. Next, add 1.0000 gram to the beam and see that the indicator needle reads 1.0000. If not, adjust the zero again. Then respan it. It is an iterative procedure. Importanly, be sure the knife edges are sharp. You will not be accurate nor be able to properly calibrate the instrument if the agate edges have been damaged by careless users, or if the instrument was not properly locked prior to moving it. If they are damaged, replace them. Finally, be sure the balance is on a firm base, not prone to vibration if someone walks across the floor. I used an old marble butcher table which was thoughtfully cut into three pieces for me: two legs and a top. This balance is tops. Keep it clean. Do not abuse it and it will last your lifetime and beyond. -- Jay Stern [Non-text portions of this message have been removed] Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://archive.nnytech.net/index.php?list=biofuel Please do NOT send Unsubscribe messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Yahoo! Groups Links To visit your group on the web, go to: http://groups.yahoo.com/group/biofuel/ To unsubscribe from this group, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
