☛ Official ☚ The Big & Dandy Scale / Balance Thread - Part 2.000±
- Thread starter frasierdog
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Tranced
Bluelight Crew
The reason I want a metal weighing pan is because it will weigh significantly more than a plastic weighing pan, relative to size. My plastic dish weighs 2556mg.
I find it bizzare how relatively unavailable they are. If a scale functions best in the centre of its range, then you'd think that loads of 10,000 mg (etc) weighing pans would be available. Place it on your scale, and just weigh out 10,020mg. This should surely be the most accurate method.
Some good suggestions there. I'm going to get to weighing some jar lids etc as well. If something is close, the I guess that would do. Or I could sand it down to size.
I find it bizzare how relatively unavailable they are. If a scale functions best in the centre of its range, then you'd think that loads of 10,000 mg (etc) weighing pans would be available. Place it on your scale, and just weigh out 10,020mg. This should surely be the most accurate method.
Some good suggestions there. I'm going to get to weighing some jar lids etc as well. If something is close, the I guess that would do. Or I could sand it down to size.
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Madrus
Bluelighter
Perhaps one of these with some quarters glued to the bottom.
http://www.oldwillknottscales.com/scoops-and-bowls.html
http://www.oldwillknottscales.com/scoops-and-bowls.html
Listening
Bluelighter
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- Aug 17, 2009
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I'd like to see someone test this with common scales like the Gemini. It makes sense intuitively, but I'm not convinced it's for sure true. I've always found mine to be +/- 2-3mg with just a bit of weight (the tray that comes with it and a post-it note typically). Does this means it would be even more accurate with a 10g tray on it? Maybe I'll test myself.
What I'm wondering is:
wouldn't you just solve the problem by taring?
I know scales don't tend to operate properly near zero, surely that isn't when zero is shown on the reading but when the measuring mechanism has to measure near it's baseline reference which is fixed (meaning in several ways). The difference for something or nothing - mechanically!
So if you use a weighing trey, this should not matter? The taring adjustment is purely a digital re-calculation, as it very well must be. Think about it?
I mean: I use a plastic trey because I am used to it / don't have a problem with calculations in my head / it has a relatively rounded mass of ~ iirc 1300 mg. Yes the reading deviates somewhat between instances / iterations but I just calculate and adjust each time in my mind and can't remember truly weird or unsafe practices with it ever.. The variance doesn't reflect absolute variances but only relative ones, in other words its inaccuracy is always kinda the same (not exact same).
Why would it help if my trey were more massive??? Or yours for that matter.
For very accurate and analytical purposes yes I use my very solid but sensitive 0.1 mg lab balance, but for regular use my crappy asian unit seems fine. Yours may not be, its possibly a gamble with sketchy ones abound.
wouldn't you just solve the problem by taring?
I know scales don't tend to operate properly near zero, surely that isn't when zero is shown on the reading but when the measuring mechanism has to measure near it's baseline reference which is fixed (meaning in several ways). The difference for something or nothing - mechanically!
So if you use a weighing trey, this should not matter? The taring adjustment is purely a digital re-calculation, as it very well must be. Think about it?
I mean: I use a plastic trey because I am used to it / don't have a problem with calculations in my head / it has a relatively rounded mass of ~ iirc 1300 mg. Yes the reading deviates somewhat between instances / iterations but I just calculate and adjust each time in my mind and can't remember truly weird or unsafe practices with it ever.. The variance doesn't reflect absolute variances but only relative ones, in other words its inaccuracy is always kinda the same (not exact same).
Why would it help if my trey were more massive??? Or yours for that matter.
For very accurate and analytical purposes yes I use my very solid but sensitive 0.1 mg lab balance, but for regular use my crappy asian unit seems fine. Yours may not be, its possibly a gamble with sketchy ones abound.
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Tranced
Bluelight Crew
Are there actually any scales which have a precision of 1mg, but aren't ridiculously expensive? I could swear my diamond max were more accurate than my Jennings JSVG-20.
Sorry, I missed this and you're absolutely right. I'm getting more and more used to my scales.
I think I've realised that when I add the weighing dish and it says 2.554 or 2.556, that ultimately this doesn't matter. To add 22mg to the former would be 2.576, and to the latter 2.578. I used to think that it had to be bang on 2.556.
I think that what bugs me now is all the constant reweighing.
Just out of interest, how accurate (roughly) can a scale with a precision of 2mg weigh to. Assuming I was weighing 22mg, and all factors were in my favor?
Sorry, I missed this and you're absolutely right. I'm getting more and more used to my scales.
I think I've realised that when I add the weighing dish and it says 2.554 or 2.556, that ultimately this doesn't matter. To add 22mg to the former would be 2.576, and to the latter 2.578. I used to think that it had to be bang on 2.556.
I think that what bugs me now is all the constant reweighing.
Just out of interest, how accurate (roughly) can a scale with a precision of 2mg weigh to. Assuming I was weighing 22mg, and all factors were in my favor?
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Not sure if that jennings really deserves its price (honestly asking/doubting, not suggesting it isnt) but 0.001 g scales can be in the same price range and to be accurate (
) lower even. Mine were like 26$ from deal extreme. Thing is, many of those cheap ones have a very cheap casing, even if the mechanics are kind of fine. But op top of that the gamble can be that some are made poorly and get a tendency to creep or be extra inaccurate etc. I would think that you can find out if that is the case by weighing one thing many times and check for inconsistencies.
I also had a rather inaccurate but super sturdy lab scale that was expensive, think it registered +/- 0.005 g. A bit of wisdom is that if possible: weigh a bigger quantity on a sturdy scale and use volumetric measurement. The sturdiness can mean: more reliable, and the volumetric measurement only reduces your error of margin relatively, so: win / profit.
What compounds I would weigh on my flimsy 0.001 g scale depends, one factor being the potency of the drug and the other being the therapeutic index. For example: Never! weigh a drug on a flimsy scale that is both super potent and is unforgiving (small therapeutic index), cause you cannot afford the error of margin and unreliability.
Learn to deal with every drug and weighed dose using the above options and everything 'in between'.
A scale like that jennings of 0.002 can regardless of anything being in your favor weigh something, register as 22 mg and it can be anywhere between 20-24 mg I think? Because the weighing mechanism doesn't notice what increment you are in, and just has a margin of inaccuracy.
Always account for the odds not being in your favor and the 'increment' being offset, other things don't 'factor' in.
) lower even. Mine were like 26$ from deal extreme. Thing is, many of those cheap ones have a very cheap casing, even if the mechanics are kind of fine. But op top of that the gamble can be that some are made poorly and get a tendency to creep or be extra inaccurate etc. I would think that you can find out if that is the case by weighing one thing many times and check for inconsistencies.I also had a rather inaccurate but super sturdy lab scale that was expensive, think it registered +/- 0.005 g. A bit of wisdom is that if possible: weigh a bigger quantity on a sturdy scale and use volumetric measurement. The sturdiness can mean: more reliable, and the volumetric measurement only reduces your error of margin relatively, so: win / profit.
What compounds I would weigh on my flimsy 0.001 g scale depends, one factor being the potency of the drug and the other being the therapeutic index. For example: Never! weigh a drug on a flimsy scale that is both super potent and is unforgiving (small therapeutic index), cause you cannot afford the error of margin and unreliability.
Learn to deal with every drug and weighed dose using the above options and everything 'in between'.
A scale like that jennings of 0.002 can regardless of anything being in your favor weigh something, register as 22 mg and it can be anywhere between 20-24 mg I think? Because the weighing mechanism doesn't notice what increment you are in, and just has a margin of inaccuracy.
Always account for the odds not being in your favor and the 'increment' being offset, other things don't 'factor' in.
kidklmx
Bluelighter
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- May 16, 2012
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- 1,311
I think the general idea is that because a 0.002g offers half the resolution, its much easier to build a reliable weighing mechanism. But yeah, I prefer volumetric dosing for most chemicals as wel, especially for novel chemicals where knowing your dose can be critical.
Btw, Those DX ones are a bit of a gamble. A friend of mine has one, and it weighed a single dose of 4-ho-MET between 20mg and 35mg.
Btw, Those DX ones are a bit of a gamble. A friend of mine has one, and it weighed a single dose of 4-ho-MET between 20mg and 35mg.
Yes I've seen like 3 of them and one was a bit iffy but the others quite alright. I've only seen maladies like creeping on occasion mostly with the iffy one.
I don't know that a lower-resolution necessarily or even typically has a bigger chance of being more reliable than a higher 0.001 accuracy scale with the reading 'rounded off randomly' to match the same accuracy. Is the cheapskate 0.001 g scale at risk being so sensitive that the mechanism is liable to getting thrown way way off? Can we generalize that even? Hmm idk but perhaps.
One certainly should not attempt weighing really tricky potent chems as the very first thing after buying a cheap 0.001 dx scale! IME if a scale is unreliable the inconsistencies will get noticed soon enough with use.
From what I remember, I never really pushed my luck and resorted to volumetric measurement or low-end dosage knowing that I can afford the worst case scenario with the error margin. Making mistakes is really not necessary the human factor is always so big. Biggest risks I took were usually from impatience and drugpiggery, regretting them immediately. Huge mistakes with ODing or eyeballing must also often be cases of hubris, ignorance and gross underestimation of having to know faintly what you are doing on a casual-analytic/scientific level.
I don't know that a lower-resolution necessarily or even typically has a bigger chance of being more reliable than a higher 0.001 accuracy scale with the reading 'rounded off randomly' to match the same accuracy. Is the cheapskate 0.001 g scale at risk being so sensitive that the mechanism is liable to getting thrown way way off? Can we generalize that even? Hmm idk but perhaps.
One certainly should not attempt weighing really tricky potent chems as the very first thing after buying a cheap 0.001 dx scale! IME if a scale is unreliable the inconsistencies will get noticed soon enough with use.
From what I remember, I never really pushed my luck and resorted to volumetric measurement or low-end dosage knowing that I can afford the worst case scenario with the error margin. Making mistakes is really not necessary the human factor is always so big. Biggest risks I took were usually from impatience and drugpiggery, regretting them immediately. Huge mistakes with ODing or eyeballing must also often be cases of hubris, ignorance and gross underestimation of having to know faintly what you are doing on a casual-analytic/scientific level.
Beenhead
Bluelight Crew
Are people using pipettes a lot these days, and are you guys checking the accuracy of scales?
I posted in another thread the proper ways to use a mechanical pipette like a pipettman or a BioRad/Fisher. I think it would be a nice thing to have in an easy to reach page. Scales and pipettes are so easy to fuck up if you dont take proper care of them and use them under the proper expectations and limits of the individual model
I posted in another thread the proper ways to use a mechanical pipette like a pipettman or a BioRad/Fisher. I think it would be a nice thing to have in an easy to reach page. Scales and pipettes are so easy to fuck up if you dont take proper care of them and use them under the proper expectations and limits of the individual model
https://blog.arduino.cc/2015/03/23/an-open-hardware-quartz-crystal-microbalance/
Wow holy shit, you can make your own subnanogram scale? (costs 500€ though)
Wow holy shit, you can make your own subnanogram scale? (costs 500€ though)
I have a Gem20 and although it's as accurate as can be expected, it's been eating through batteries like crazy. If I don't remove the batteries after each use a brand new pair will last only 3 days. Has anyone else had this issue and have you found a solution?
Apologies if this has been discussed before.
Apologies if this has been discussed before.
It must be shorting? If that is the case then the solution is to find the short, I guess by running whether anything may be touching inside. If it cannot be found then the short is possibly somehow inside the circuit (which I would expect to get warm), batteries don't just empty - the current must be running it dry and the energy translated as something, if not work then heat.
I currently take a prescription 25mg pill.. then need to cut it in half to make it 12.5mg. I then take that and cut that in half to make it a 6.25mg I'm doing all this with a pill cutter which isn't to Accu rate. I know the scale I'm looking at can possibly increase accuracy?
GeminiPro gpr 20
Or would it be better to take the 25mg pill and shave off the 6.25mg ?
GeminiPro gpr 20
Or would it be better to take the 25mg pill and shave off the 6.25mg ?
Combine the two methods?
Weigh the pill, calculate what a quarter should be by dividing by 4, proceed to cut it in quarters and weigh it to check how close you are.
If you need to you can scrape off some from another part of pill until you are nicely at that quarter value but depending on what kind of pill it is you might want to make sure it's from the inside, not some lozenge layer.
Actually though, all of this is only relevant if you are like tapering a benzo prescription which should be nice steady and accurate. So it depends on what you are taking your meds for (well in my personal opinion!) if it's really important to be accurate.
Weigh the pill, calculate what a quarter should be by dividing by 4, proceed to cut it in quarters and weigh it to check how close you are.
If you need to you can scrape off some from another part of pill until you are nicely at that quarter value but depending on what kind of pill it is you might want to make sure it's from the inside, not some lozenge layer.
Actually though, all of this is only relevant if you are like tapering a benzo prescription which should be nice steady and accurate. So it depends on what you are taking your meds for (well in my personal opinion!) if it's really important to be accurate.
Thank you for responding so quickly.
It's not a Benzo but an SSRI Fluvoxamine aka Luvox.
Tapering an anti depressive drug is very important and typically 10% reductions are done every 4 weeks or more .
It's a oval shape pill and when it time cuts time to cut the 12.5 mg it's not a clean cut and always different.
To put things into perspective that 6.25mg makes my eye pain bearable to unbearable.. I know it's such a small amount.
I'm trying to go as low as I can with my meds because they are causing severe eye pain. In total I take 43.75mg Luvox
I have read every post in this long thread in regards to weighing in mg. I realize what I'm trying to do would require a more expensive 1k plus scale..
I also could take 12.5mg luvox and take 12.5 of distilled water mix it up and use a syringe. But really don't feel like using this method.
It's not a Benzo but an SSRI Fluvoxamine aka Luvox.
Tapering an anti depressive drug is very important and typically 10% reductions are done every 4 weeks or more .
It's a oval shape pill and when it time cuts time to cut the 12.5 mg it's not a clean cut and always different.
To put things into perspective that 6.25mg makes my eye pain bearable to unbearable.. I know it's such a small amount.
I'm trying to go as low as I can with my meds because they are causing severe eye pain. In total I take 43.75mg Luvox
I have read every post in this long thread in regards to weighing in mg. I realize what I'm trying to do would require a more expensive 1k plus scale..
I also could take 12.5mg luvox and take 12.5 of distilled water mix it up and use a syringe. But really don't feel like using this method.
You do realize that your scale has 1 mg accuracy only not that reliable and importantly that the pills contain quite some bindings and fillers so you don't have to weigh 6 mg precisely but whatever a pill weighs divided by 4? It should be accurate enough for that.
Why would you need an expensive scale exactly? Maybe it would help if you shared the exact details of what you would try to do by weighing and why your equipment and method available wouldn't be good enough? Step by step if necessary. Either I am thick and misunderstanding, or despite reading the posts you are confused about something and are good to go after all. What does a whole pill weigh?
Agreed that dissolving pills is far from ideal, for one fluvoxamine is only moderately soluble in water.
Why would you need an expensive scale exactly? Maybe it would help if you shared the exact details of what you would try to do by weighing and why your equipment and method available wouldn't be good enough? Step by step if necessary. Either I am thick and misunderstanding, or despite reading the posts you are confused about something and are good to go after all. What does a whole pill weigh?
Agreed that dissolving pills is far from ideal, for one fluvoxamine is only moderately soluble in water.
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Well I thought the scale at least needs to be able to weight the 25mg pill minus the 6.25
I just ordered the scale so it should be in today or tommorow. As soon as it comes in I'll weight the pill and report back.
Thanks for the continued help..
I just ordered the scale so it should be in today or tommorow. As soon as it comes in I'll weight the pill and report back.
Thanks for the continued help..
