14 degree Baume Gum Arabic

Discussion in 'Alternative Processes' started by shinn, Jul 8, 2004.

  1. shinn

    shinn Member

    Messages:
    92
    Joined:
    Apr 11, 2004
    Location:
    Bezerkeley,
    How would one make this? The defination in my chemical dictionary makes little or no sense to me.

    I have some powdered Gum Arabic and methylparaben which I plan to use as a preserative.

    Thanks
    Happy Days
     
  2. Jorge

    Jorge Inactive

    Messages:
    4,532
    Joined:
    Sep 6, 2002
    Shooter:
    Large Format
    You need a hydrometer to make a 14 Baume solution. for liquids heavier than water the conversion is:

    SG (specific gravity)=145/(145-Bè)

    If you substitute 14 for Bè then what you are looking for is a solution with a specific gravity of 1.106

    If you ask me it is easier if you just eye ball it, maybe Clay or Kerik can give you some guidance. I would say the solution should be similar to a saturated solution of water and sugar. Good luck.
     
  3. clay

    clay Subscriber

    Messages:
    1,124
    Joined:
    Nov 21, 2002
    Location:
    Asheville, N
    Shooter:
    Multi Format
    The pre-mixed stuff I get from B&S pours about like the light colored Karo syrup. Definitely has more viscosity than sugar water. Check out Sam Wang's article about tri-color gum on www.unblinkingeye.com. I believe he mixes his own gum solution from dry gum, and if I remember correctly, he outlines his procedure.
     
  4. Jorge

    Jorge Inactive

    Messages:
    4,532
    Joined:
    Sep 6, 2002
    Shooter:
    Large Format
    Well there you go, make a solution that pours like Karo and go from there. I doubt you have to be exact in this process. The people who were doing it 80 years ago probably did not use a hydrometer...:smile:
     
  5. Kerik

    Kerik Member

    Messages:
    1,467
    Joined:
    Nov 24, 2002
    Location:
    California
    Shooter:
    Medium Format
    Here's an excerpt from my gum printing workshop manual:

    "I have only ever used one type of gum arabic. It is the spray-dried powder available from Bostick and Sullivan. Gum arabic can vary widely from manufacturer to manufacturer and from one year to the next. The B&S gum has been very consistent and works very well. You can buy it in solution, or mix it yourself from the powder as follows:

    Add 300 gm powder to 1000 ml of water. Stir vigorously until the gum is mixed as much as possible. There will probably be quite a bit of stuff floating on the surface, but that will mix in eventually. Place the container (covered) in the refrigerator for several days and stir it several times a day, mixing in any lumps that may be present. After a few days, there will probably be a little bit of foam on top, which you can just skim off. To preserve the gum solution, add 3 ml of 1% sodium benzoate per liter. Place the gum solution in a plastic bottle so you can squeeze out any air in the bottle when you seal it. The gum does not need to stay in the refrigerator once ready for use."

    I've never determined it's Baume rating, but I know that it works very, very well.

    Kerik
     
  6. shinn

    shinn Member

    Messages:
    92
    Joined:
    Apr 11, 2004
    Location:
    Bezerkeley,
    Thanks guys,

    I just got a hydrometer and have the same formula/equation, the only thing I'm missing is the MW of the gum which I need to find the SG??? I do know that keriks formula is the same ratio I've been using myself and awfully close to 14 baume and I'll start there. And will proly use the Benzoate rather than the Methylparaben because the benzoate has proven its self.

    Once again thanks everyone.

    Happy Days