Re: Mixing Ratio: 14 Baume Gum From Powder

[Michael Koch-Schulte <mkochsch@shaw.ca>]

Just check my math here for me...  So the old "2 parts gum to 5 parts water"
(1:2.5) mixes a tad on the thick'ish side -- for me at least -- at this
point in my life ;^). The mixes you and Art cited are just a shade under 1:3
(to just a little above 1:2.6). Until my Baume-O-meter arrives I'm going to
work with 7 g. in 20 ml. of water ~ 1:2.85. And maybe try 8.5 g. in 25 ml.
Sound about right?! Thx.
~m

RNP Arrays: Open Source Digital Negative Project
www.inkjetnegative.com

----- Original Message ----- 
From: "Christina Z. Anderson" <zphoto@montana.net>
To: <alt-photo-process-l@usask.ca>
Sent: Wednesday, August 29, 2007 8:03 AM
Subject: Re: Mixing Ratio: 14 Baume Gum From Powder


> Hi Michael,
> The answer to your question is to buy a $30 baume meter from Cole Parmer
and
> also a test tube tall enough so it can be submerged mostly (about a foot).
> I've been communicating with Art Chakalis about this and he has a measure
of
> 288g gum to mix up a liter of combined solution.  I found with my gum
arabic
> approximately 840ml water to 288 made a liter.  But Art pointed out that
> different gums have different moisture content so that this measurement is
> never exact, hence the baume meter. But about 280-320g gum = 14 baume.
>
> SO, I was on a wild goose chase about strengths of gum throughout history
> and found that they varied from 10% to 50% gum!  Take your pick.
> Chris
>
>
> ----- Original Message ----- 
> From: "Michael Koch-Schulte" <mkochsch@shaw.ca>
> To: <alt-photo-process-l@sask.usask.ca>
> Sent: Tuesday, August 28, 2007 11:01 PM
> Subject: Mixing Ratio: 14 Baume Gum From Powder
>
>
> > How do I mix ~14 baume gum from powder? It's not 1g. gum to 2 ml of
water
> > that's about 18 baume so I've read....and I'm finding it too thick? A
> > sub-question might be how could I water down a 1:2 mixture. So what do
> > people do 1:3? 1:4? I read somewhere on the list someone (Guido) was
using
> > 1:4.5
> >
> > ~m
> >
> > RNP Arrays: Open Source Digital Negative Project
> > www.inkjetnegative.com
> >
> >
>
>