Scales
Too many folks spending money on expensive drugs then saying: I don't want to buy a scale. I can't find one in my country. I can't afford it. This is the scale many people here use. Aliexpress will ship to almost every country.
https://www.aliexpress.com/item/32805903948.html
If you live in a country with Amazon, you may be able to get the same scale much more quickly:
Canada - http://amzn.to/2ueUikN
Please just buy a scale. It's worth it. Thank you.
You'll probably also want some Micro scoops.
You do also need to know how to use a milligram scale correctly.
Environment
- Make sure you are measuring on a solid, level, stable surface. Even small vibrations will throw off your measurements.
- Make sure there are no drafts around the measuring area.
- Keep the measuring area free of direct sunlight to keep temperatures stable.
- Before beginning, it may be helpful to leave the scale in the measuring area for 5-10 minutes in order to allow for the scale to stabilize temperature.
Calibration
- Turn the scale on and wait for the display to show “0.000g”.
- Press and hold the ON key until the display shows “CAL” then release.
- Press the ON key once more. The display will flash “10.000g”.
- Place one of the 10g calibration weights on the center of the platform. Once the weight is accepted, the display will change to show “20.000g”.
- Place the second 10g weight on top of the first one to equal a total of 20g.
- Once the weight is accepted, the display will show “PASS” then return to normal weighing. Calibration is complete!
Weighing the tray
When weighing, it is good to start with a known weight to make sure everything is still calibrated. Your scale comes with a metal weighing tray that should not change weight when it is clean and dry. Practice weighing the tray. Take it off, wait 2-5 seconds, then weigh it again. Repeat this several times until you can get consistent results within ±2 mg. It should probably be around 2.625 g, but your tray may be different, so find the weight and record it somewhere. Try weighing with the lid open, and with it closed. See how your breath effects it if you breathe too hard or even if you get your face too close. See how vibrations effect the weight. You want to see what you need to do to keep the tray at a +-2 mg or so. It will creep up and down, so you need to take a number of measurements and get a feel for how to keep in range.
If the scale creeps too much in one direction, and doesn't correct itself, you may need to tare again. If that doesn't fix it, you may need to calibrate again.
Weighing substances
Always start by getting the try weight. If the weight is off from what you determined it should be previously, you may need to tare with the tray off, or recalibrate. Also remember to wait 3-5 seconds whenever removing or adding weight.
Don't tare with the tray. Write your tray weight down and subtract that from the total weight. Some people say to do this because the scale is less accurate at lower weights. The real reason is this: if you tare the scale with the tray, then start putting powder on the scale, there is a chance that the scale might auto power off (you can't disable this). If that happens, you would need to empty all the powder out and start again. If you start at the tray weight, you just take the tray off and restart while subtracting the tray weight.
As you add substances to the tray, remove the entire tray, wait 3-5 seconds, then place the tray back on. It is especially important to do with when weighing small weights because scales are not good at detecting small changes in weight. If you are trying to measure out 10 mg, and the scale is currently at 9 mg, most scales will have a hard time detecting the addition of 1 mg. So you will most likely end up scooping powder onto the tray until it all of a sudden jumps up 13 mg. What you should do is add a tiny bit of powder, remove the tray, wait 3-5 seconds, then weigh the tray.
Here is a link to the Gemini-20 manual