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Decent inexpensive powder scale?
- Thread starter WobblyHand
- Start date
- Joined
- Apr 29, 2019
- Messages
- 2,257
Weighing all of those on a balance scale will be very tedious. I would find a digital scale that has one more digit of accuracy than you need, that way it should be accurate at the resolution that you need.
Make yourself a set of test weights out of brass that are in the weight range of what you will be measuring. Mark the weight on them using a method that will not add or remove anything from them. (A marker adds ink and engraving removes metal. If you want nice engraved marking make the weights slightly heavy, engrave the marking then continue to remove material until you hit the weight that you marked.) Once you know the weight of the test weights you can always toss them on every once in a while to check your scale for drift in the range that you are measuring. Some scales will drift more around the high and low limits of their range, middle of range is the most accurate.
You do not necessarily need a scale that reads out in grains. You are just sorting by weight so any unit of measure could be used.
I do not have a scale that has precision to what you are looking for so I can not make a recommendation. All of my weighing is to see if part A or part B weighs more, I do not care what the actual weights are. All I need is repeatability.
Make yourself a set of test weights out of brass that are in the weight range of what you will be measuring. Mark the weight on them using a method that will not add or remove anything from them. (A marker adds ink and engraving removes metal. If you want nice engraved marking make the weights slightly heavy, engrave the marking then continue to remove material until you hit the weight that you marked.) Once you know the weight of the test weights you can always toss them on every once in a while to check your scale for drift in the range that you are measuring. Some scales will drift more around the high and low limits of their range, middle of range is the most accurate.
You do not necessarily need a scale that reads out in grains. You are just sorting by weight so any unit of measure could be used.
I do not have a scale that has precision to what you are looking for so I can not make a recommendation. All of my weighing is to see if part A or part B weighs more, I do not care what the actual weights are. All I need is repeatability.
- Joined
- Dec 18, 2019
- Messages
- 7,495
You better believe it is tedious! It's only due to sheer stubbornness that I'm persisting. I found someone who has done a lot of this before and they recommended a scale that is cheap enough for me to try. In the meantime, I added a washer as a spacer to move the magnet closer to the beam, and that damps the movement to about 1.5 cycles, which is a great improvement.
At the moment, I'm not sure how this mold should cast, as there were two sets of matched pins supplied, (hollow point depth and weight) and the pins aren't labeled. So I've been sorting via weight to get rid of hidden inclusions and whatnot.
At the same time I'm still sorting out my casting technique. The melting pot is on a PID which helps a lot, but it's not perfect. To keep the mold from cooling off too much I have the mold on a hot plate, but it isn't PID controlled. The mold claims 27 grains is the cast weight with pure lead, but I am getting most of my slugs at 28.35 grains. So there's a few more things to check out. I'm hoping a digital scale would help - we'll see. Something is still off, as there are some minor wrinkles in the slugs, so I need to probably keep the mold hotter. The lead temp is already on the warm side with it oxidizing a little faster than I'd like.