[Alt-photo] Re: lump gum

[Laura V]

Oh I see, so maybe at the drug store. I didn't know what it was. I read 
that it is derived from thyme, so maybe thyme oil would work as well? 
Thanks!

Laura

On 10/19/13 3:46 PM, Jorj Bauer wrote:
> Glyoxol is a hardener. You probably don't want to use that as a preservative for gum.
>
> Thymol should work. I'd be surprised if you couldn't find that; it's commonly used as an anti-fungal for finger- and toe-nails.
>
> -- Jorj
>
> On Oct 19, 2013, at 11:40 AM, Laura V <laura at lavatop.com> wrote:
>
>> Thanks for this. I have not used a preservative before (mainly because I don't know where to buy it). I usually just mixed a small batch (when I had the powdered stuff) and kept it in the fridge and used it within 2 weeks.
>>
>> Unless, is glyoxol a preservative? I have some that I used in paper sizing. It would be handier to always have the gum pre-mixed.
>>
>> Laura
>>
>> On 10/19/13 3:01 PM, Guido Ceuppens wrote:
>>> Laura,
>>>
>>> I used the following procedure with lumps of gum:
>>>
>>> 300 grs of gum are slowly dissolved in 850 ml of cold water, this may take
>>> several days. The impurities are then filtered or fished out, some
>>> recommend to suspend the lumps of gum in a muslin bag to prevent the
>>> impurities to float in the solution. Once dissolved a preservation agent
>>> must be added to the solution: in the past I have added either 15 ml of
>>> formol or 7.5 grs of sodium benzoate. I have used the thus prepared gum for
>>> years without it going bad (I mainly use casein now but occasionally use
>>> gum that was prepared from powder –same procedure- 7 years ago).
>>>
>>> Welcome back and good luck,
>>>
>>> Guido
>>>
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>>>
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