Bicarbontate of soda OPINIONS NEEDED!

christrom

Sr Member

• Jan 11, 2013

• #1

Hi everyone,

My diorama will soon need to be snow covered and as well as making some of it using lightweight spackle I want to use the good old PVA and sodium bicarbonate method.

I was looking at different techniques and I happened across a modeller who had to throw away a large part of his collection because the soda had started to eat away at his model's paint jobs, resulting in a slimy brown mess.

Now, firstly he had used enamels I think, mine paint is all water-based, and I was thinking that perhaps he used baking powder which has other stuff in it apart from pure bicarbonate of soda. but I would much appreciate anyone on here posting with info on this?

If you have any models 10 years + with bicarbonate of soda in them... how are they holding up? :confused

Many thanks

 

P

pengbuzz

Sr Member

• Jan 11, 2013

• #2

Baking powder is baking soda and corn starch; I wonder if that combo would do anything.

If you're worried about the effect baking soda would have, try looking at your local hobby store in the model railroad section for the snow they use for that application. Depending upon where you live, try Hobby Lobby; they have an online 40 percent off coupon printable from the internet that can help you save on the cost-

Snow-tex:

DecoArt 4-ounce Snow Tex | Shop Hobby Lobby

coupon:

http://www.hobbylobby.com/assets/dynamic/_weekly.coupon/2013_2_coupon.gif

 

Exxos

Member

• Jan 11, 2013

• #3

Pretty much never use it. Sodium bicarbonate reacts with everything and using it basically makes your model a ticking time bomb of deterioration. It will look great at first, so if it is just a throw away model for a film, you can get away with it. But if it is a long term display, it will deteriorate, maybe in a month or in twenty years, but it will in a catastrophic manner.

The presence of corn starch is an entire set of problems on its own. I've seen models literally "digested" and even overrun with huge patches of mold. Once the bicarbonate has had its way with the model, I figure it is so denatured and exhausted that it does not keep the fauna at bay.

 

christrom

Sr Member

• Jan 11, 2013

• #4

Thanks, I appreciate the input and it is definitely making me think twice about using it

 

LMFAOSchwarz

Sr Member

• Jan 11, 2013

• #5

When I saw the title, I thought maybe you were making on of those school volcanoes. :lol

Wish I knew what to suggest, though. My only experience close to that was needing temporary snow on a model city for a short film. I used plain old table salt, and it photographed beautifully. I certainly wouldn't recommend THAT for anything permanent! :confused

 

christrom

Sr Member

• Jan 11, 2013

• #6

It is a shame because bicarb of soda looks so beautiful, but I 'm not sure I want to risk it on something I've spent nearly 3 years making. I'll have a look at the woodlands scenics stuff...

 

LMFAOSchwarz

Sr Member

• Jan 11, 2013

• #7

It might sound silly, but it couldn't hurt to check out Christmas displays, you know, little manger scenes and such. I doubt you'd find snow in a desert, but I'm sure that hasn't stopped some from adding it anyway!
There must be some kind of non-reactive substance which resembles snow...

 

BornKilr

Sr Member

RPF PREMIUM MEMBER

• Jan 11, 2013

• #8

I've never used this product before but I've seen it in stores and it looked pretty cool.

http://scenearama.woodlandscenics.com/show/Item/SP4123/page/1

 

christrom

Sr Member

• Jan 12, 2013

• #9

^ Thanks for the link. I'm going on a hunt for marble dust today and microballoons, both are supposed to be pretty good but if they fail I'll perhaps try some of that stuff

 

Z

Zarancorde

New Member

• Jan 12, 2013

• #10

i have heard th
e filler to a disposable diaper makes for a decent snow substitute. cut one open, soak the pellets, allow to dry andarrange.

 

christrom

Sr Member

• Jan 12, 2013

• #11

So, been experimenting

- tried talc but it is very opaque and clumpy
- tried scenic snow and it is pretty good but the particles are like salt - bit too big
- ordered some microballoons - I'll see what these are like

also been looking at glass frit, which is basically powdered glass. This stuff looks amazing, and will sparkle like snow... could be a winner