Darkroom Scales

[tgtaylor]

I'm in the market to replace my well-used triple beam balance. What's some good ones to choose from? I need to measure to the 1/10th gram. I've been eyeballing this on at B&H http://www.bhphotovideo.com/c/produc...oom_Scale.html

Thomas

[Taija71A]

Ohaus, makes very nice Darkroom Scales...

Just FYI Thomas, I have used an older model of this Ohaus Scale (LS200) for many years... With nary a problem.

If my scale was ever to 'fail me'... I would definitely replace it with a CS200.
Enough said... Just buy it. Highly Recommended!

-Tim.

[Jim C.]

Any reason you'd want to go electric rather than a mechanical scale ?
I've used a Ohaus triple beam for decades they take a beating and keep on measuring
no batteries or wall wart power supplies needed.

[tgtaylor]

I am also considering an Ohaus triple balance. What I like about the mechanical scales is that they allow you to measure 1/20th gram mark unlike the (affordable) electric sales which measure in 1/10th gram increments.

Thomas

[Taija71A]

Ohaus of course, makes beautiful Mechanical Triple Beam Balances...

But, I don't 'believe' that they come in (0.05 g Accuracy)...
*In the size (200 g Capacity) -- That you originally cited.

Thomas, what are you trying to mix that requires 0.05 g accuracy?
Phenidone? Just curious...
--
If you 'truly' need (0.05 g Accuracy)...

Have you given thought to 'perhaps' preparing (beforehand), a very dilute
(1% 2%, 5% 10%) 'Stock' Solution of that particular chemical? Just a suggestion...

Any reason you'd want to go electric rather than a mechanical scale?

If size and/or weight considerations are an issue...
Electronic Scales are smaller and lighter.

Best regards, -Tim.

[LabRat]

That Ohaus Electronic Scale linked is a good price, but do further research of that model to see what the resolution of the scale steps are... (There are different models/different price point units that have more/less "simplified" scales...) I remember a while ago that the suitable Ohaus model was hundreds of dollars... 10ths/gm is good for foto use... (20th/gm models are much more $$$, and very sensitive to vibration and even drafts in the room!!!)

The measuring range is OK if you are making a liter or two of solution, but for larger amounts, you will be back to your triple beam!!!

Triple beam balances get very sluggish <0.3/gm, so like Tim said, you can mix smaller amounts by making stock solutions... (Phenidone, restrainers, etc can be mixed that way...)

My "daily driver" is an old Ohaus "Harvard" balance, that requires separate weights, but will weigh out 0.1/gm to 5lbs... And I can just add another cup to the other side to balance out the tare weight so something less to think about... (FYI/ Good measuring cups are a package of paper or styro cups... Usually about exact equal weight cup to cup from the same batch...)

And don't even think of buying cheeep digital no-name scales... I bought a cheeep pocket digital scale from a head shop to set-up a few turntable tracking weights, (then to the darkroom to weigh out small chems), and 3 died within days, so I had to return them... Finally got a good one, but it only lasted a few months... (Don't bring one to your "big score"!!!)

Steve K

[Taija71A]

That Ohaus Electronic Scale linked is a good price... 10ths/gm is good for foto use...

Agreed in full 200%.

... but do further research of that model to see what the resolution of the scale steps are.

The Ohaus CS200 is 0.1 g... Readability, Repeatibility and Linearity.

... 20th/gm models are much more $$$, and very sensitive to vibration and even drafts in the room!!!)

"Akchoo!!!"

... (FYI/ Good measuring cups are a package of paper or styro cups...

+1. Coffee filters and paper cupcake liners... Also 'work in a pinch!'

I am pretty sure that the CS 200 also has a 'Zeroing Range'.
My Ohaus Unit certainly has this Function.

Steve knows... Darkroom Scales!

[tgtaylor]

Well here is the scale that I finally went with:

It's the Ohaus CT200-V which, unlike the CS200, is readable to the 0.01gm which I commonly need to measure to since I mix most of my formulas from scratch for single use and the math usually goes to the 2d decimal place. It is shown above reading the 1.97 gm weight of a plastic disposable condiment container for salsa which is ideal for measuring small qualities of chemicals such as silver nitrate or tartaric acid. Incidentally this weigh agrees within a 1/10 gm with my triple beam which is an Ohaus knock-off but unlike the triple beam is repeatable. It comes with a plastic scoop for larger quantities which is much more convenient than using coffee filters. I picked it up off ebay in unused condition with box, calibration weights, etc for $100.

Thomas

[Tin Can]

I went the cheap way and think this will be fine for my usage. I got it yesterday, very nice device and it is calibratable. Already used it, it works well and is warrantied 10 years.

http://www.amazon.com/gp/product/B00...ilpage_o01_s00

In my past I worked with analytical balances, such as these, that are way overkill for my current purposes.

http://www.amazon.com/Ohaus-Pioneer-...tical+balances

[Taija71A]

... It's the Ohaus CT200-V...
... I picked it up off ebay in unused condition with box, calibration weights, etc for $100.

'Good spot' Thomas.
Used, but in unused condition is always nice!

... And think this will be fine for my usage. I got it yesterday, very nice device and it is calibratable. Already used it, it works well and is warrantied 10 years.

Amazing price Randy!
Yes, it should be just fine for your usage. Enjoy!