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Brie -Anne Bryan
10-05-2011, 4:28 PM
Hi all!

I have a rather large colorfill on acrylic job coming up and thought I'd try the flood/scrape and clean method. Usually I laser through the paper mask that comes on the acrylic, but these particular acrylic plaques don't come with anything on them:( My problem is that I don't know where to get Denatured Alcohol. Does anyone know where to get it in Canada? Is it even called that here....?....I'm not sure. Is there anything else that will work on acrylic?
Also, what do you think would be the best paint to use? I need a shade pretty close to process blue.

Thanks in advance!!

Dee Gallo
10-05-2011, 5:46 PM
Brie-Anne,

I would put some vinyl signmaker's transfer tape on it before burning. It's lightweight and comes off easily. Whenever I clean thin acrylic, I use rubbing alcohol which is a watered down version of DNA, easy to find and less aggressive to the plastic. It takes the smoke off quite well without crazing.

I use Testor's oil based model painting enamel (Flo-Quil) on plastic all the time and clean it off with De-Solve-it which is a waterless orange based cleaner. But, I know other people have used acrylic paints with success too (water based). Testors also make an acrylic version for model painting. I find enamel dries to a much harder finish than artist's acrylics.

cheers, dee

Mike Null
10-06-2011, 4:34 AM
A paint store which sells shellac will also sell dna.

Chuck Stone
10-06-2011, 12:59 PM
you can probably find 'methyl hydrate' in the Canadian stores. Not quite the same as the denatured
alcohol we get here, but similar enough. Our denatured alcohol used to be mainly ethanol (distilled
from grains .. ie moonshine) with enough wood alcohol (methanol) added to make it poisonous. This
is because the grain alcohol was less expensive to produce than methanol. But there are many blends
on the market. Some are about 50/50 and some are 90%+ ethanol with added benzene and toluene.
Methyl hydrate is nasty stuff, though. It gets into your system through the skin and lungs. So wear
good gloves and ventilate!

John Noell
10-06-2011, 3:08 PM
The terms "denatured alcohol" and "rubbing alcohol" are non-standard and vary in the alcohols and concentrations found therein. It's a bit frustrating, especially when the retail vendors often do not know what is in it themselves. We buy "methylated spirits" here but trying to find out exactly what is in it, and at what concentrations, is very difficult.

Chuck Stone
10-06-2011, 3:39 PM
John .. that's true. But you do have the MSDS to refer to. They usually refer to each ingredient
as a percentage, so it isn't impossible to find out.

FWIW .. the MSDS's I've found show that most 'methylated spirits' are what we are looking
for (but don't necessarily get!) when we buy 'denatured alcohol'. Basically, ethanol with
about 1% denaturing additives. Often what we get has a lot of water in it.

Tony Lenkic
10-06-2011, 4:48 PM
Brie-Anne,

Where are you located? You may find this product in local marine.
It is 90/10% mix of ethanol and additive that makes it "denatured"

http://captphab.com/HomePage.html

Michael Hunter
10-06-2011, 7:21 PM
The official UK formula for methylated spirits ("fully denatured") is as follows :

90% ethanol
9.5% methanol ("wood alcohol" or "wood naphtha")
0.5% pyridine (this is what is supposed to make it taste bitter and so undrinkable)
to this must be added -
trace of mineral naphtha (from petroleum) : 3.75 litres per 1000 litres of above mixture
trace of synthetic dye (methyl violet) : 1.5g per 1000 litres of above mixture

Is there an equivalent American standard or recipe for DNA?

John Noell
10-07-2011, 1:22 AM
John .. that's true. But you do have the MSDS to refer to.
Here in Fiji, the vendors have no idea what a MSDS is! One of the joys of life on a small tropical island. :) Even stuff like pesticides lacks MSDSs here. A friend with a pest control business has regularly asked me to get MSDSs for him because the Fiji vendor does not have them. (We also see a LOT of Chinese stuff that would never make it into the USA. No MSDS at all.)

Chuck Stone
10-07-2011, 10:12 AM
OUCH! that would be a bit scary...

Jean Paull
10-07-2011, 1:32 PM
My experience has been that denatured alcohol is not available in Canada. Rubbing alcohol is a similar mix of alcohol and water but also has some oils and other ingredients added to make it gentler for skin. The additives can leave residues which can be a problem, depending on your usage.

Bill Jermyn
10-08-2011, 6:54 AM
I use isopropyl alcohol available from any pharmacy, Walmart, etc. Not sure if it's the same stuff, though.

Richard Rumancik
10-08-2011, 2:28 PM
Brie-Anne, if you absolutely need DNA you can probably get it in Canada from Anachemia. I bought it 10 years ago and I believe you can still buy it from them. Here is the MSDS.

http://www.anachemia.com/msds/english/4099.pdf

It is 85% ethanol and 14.3% methanol. But - it will be expensive, and there will be a minimum purchase order value.

They will take lots of info as they want to ensure it is being used for a legitimate purpose. Sometimes they may have "expired" reagent-grade stock that you can get at reduced price. You certainly don't need reagent grade for what you are doing but since they are a laboratory chemical supplier they don't sell much chemical with low grades of purity.

But I would still tend to exhaust all the cheaper alternatives before going this route.

Greg Bednar
10-08-2011, 2:45 PM
Available at all state liquor stores in the lower 48. Although in Ohio - I had to complete extra paperwork. Start with you local liquor stores in Canada. Further information it and it's availability in Canada is here: http://en.wikipedia.org/wiki/Everclear_(alcohol) Mine cost about $15.00 USD. I only use it for lens cleaning, so it may be cost prohibitive for your use. But if you really need it....................

Brie -Anne Bryan
10-20-2011, 11:03 AM
Hi everyone....Thanks for all your input and suggestions:)
Dee...I tried to find Testor's here in Canada...(I'm in Winnipeg, MB) and I can't find it. Do you know of any other brand that would work? I will try my local artists supply store to see if they have any sort of model enamel paint. Also, I thought it wasn't good to use oil based paints on acrlyic?
I had some oil based spray that I tried out on a scrap piece and sure enough it looked all cracked and the acrlyic started to craze around the edges:(
Do people really have a good result with just artists craft paint?

Thanks!

Dee Gallo
10-20-2011, 4:33 PM
Brie-Anne,

I don't know of another brand off hand, but there must be a hobby paint available in Canada. I have not had any problems with color fill using oil based enamels, but you can get special plastic paints through Dick Blick which are water based and stick to plastic (possibly under the name of Deco?). I don't like to use acrylics on plastic because it crawls and it can peel off because there is no tooth to hold it. Plus the finish is not very hard in my opinion. But that's just me. Others have had success and like it. I think that if you are using a laser to engrave and it leaves a slightly rough finish you would be fine with acrylics.

The spray paints are not the same, since they have more solvent to make them thin enough to spray and the solvents are more aggressive on plastic. I would not recommend those.

Here is a picture of some recently color filled plastic tiles. I've had ten of thousands of these out there for 5+ years with lots of handling and cleaning with no loss of paint.

Hope this helps, dee

Richard Rumancik
10-20-2011, 6:26 PM
Brie-Anne, you need to try a hobby shop for Testors enamels. Eliminator RC (eliminator-rc.com) has it on their website and probably in the store as well (Higgins street/Winnipeg). You could also try Gooch's, Cellar Dwellar, and Elmwood Hobby.

Brie -Anne Bryan
10-21-2011, 12:23 PM
Hi Dee,
Those look great! Do you flood fill or brush?
I was also thinking of using auto airbrush paint....it's nice because it's waterbased but has a catalyst added for hardening. It works great on glass but I don't know about acrylic. Has anyone used it on acrylic with success?

Hi Richard,
Thanks for your help...I will have to check those places out:)

Dee Gallo
10-21-2011, 12:40 PM
Hi Brie-Anne,

Those are only 1" wide, so I use a small brush pick, which looks like a tiny Q-tip with a plastic handle. It is cleanable, so I use them over and over until the brush part wears down. You can get them in two sizes, tiny and even tinier. For single lines which have to be very precise, I use a 5x round artists brush. But the concept is the same as flood filling, you over-fill the grooves and squeegee off the extra, let it set for a minute and then wipe off the haze with solvent (I use De-Solve-It) on a paper towel. For the color blended sections, I apply paint in a specific order based on what will cover something else, saving the blending color for last. So usually it's red first, blue, green then yellow. Blend with the same brush pick.

cheers, dee

edit: I forgot to mention the gold. It will leave sparkles on everything if not done first. So I usually do the gold first and clean it off so it can sit overnight to harden well. Then the other colors will come out clean. But if you want a glittery look, do them all at the same time.