Re: [RCSE] Digital Scales

[Keith Smith]

I have used many scales while working in test laboratories. My all around preference is the old standard Ohaus 2610 g Triple Balance Beam Scale. They're extremely accurate, and with a inexpensive set of calibration weight set, you can easily maintain your scale accuracy with no problems. I am able to mix as little resin as 10 grams of material, and yet stay within the tolerances of my epoxy mixing ratios. Generally speaking,  your inexpensive digital scales can easily be off by several percentages. That may not be a major concern when mixing resins that require 20 % by weight on an ounce or more of material, but mixing smaller amounts of material, especially materials that require a harden at 7 % by weight, that's when you begin to run into difficulties.   The majority of the modelers seldom calibrate their scales, and for the most part you may not experience any noticeable problems if you don't calibrate your scale. However, if you are really concerned about having the exact mixing ratios, and want to insure you have the optimum strength, you may want to consider investing in a scale that will give you the proper accuracies! You can buy a good used triple beam scale for as little as $ 15.00, or near new for about $ 35.00. I have a habit of checking my scale calibration nearly once before using it. I've made three standard weights. My weights range form 10, 30. and 50 grams. If you're really serious about your calibration, you can buy an inexpensive calibration weight sets for about $12.00 I use my three normal standard weights regularly,  because that's my normal mixing range. All  triple beam scale are quick and easy to make tare any adjustments. Every time you place any mixing cup on your scale,  you automatically see the tare weight zero out. I also suggest spraying a very light mist of WD-40 on your plate,  this helps prevent from epoxy build-ups, but be careful, not to over spray with the WD-40. Heavy spraying of WD-40  could affect your scale calibration. It's also best to periodically wipe your scale down with good old reliable isopropyl rubbing alcohol, or even Windex window cleaner.  I suggest Checking out E-bay. They always have triple beam scales for scale. When you buying any scale iy's best to clean it, light lube it as required, and always double calibrate the first usage of any scale, whether it's new or a used scale before ever using it!   I hope all that read this, found some useful information.   Keith