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It's my first time painting a large canvas.

I want to buy Golden paints but I am not sure how much to get, with some room for experimentation too.

Matt
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Arturino
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1 Answers1

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Get yourself a 10 x 10 centimetre square of your canvas and paint a test piece. Once you are happy with your painting measure the amount of paint that was used and then multiply it by 400. That is how much paint you will need to create the same image on a two by two meter square canvas.

2m = 200 cm

200 cm x 200 cm = 40 000 cm^2

10cm x 10 cm = 100 cm^2

40 000 cm^2 / 100 cm^2 = 400

Your 10 cm^2 canvas is 400 times smaller than your 2 m^2 canvas.

Going the other way, you would have to scale the test piece by 400 times for it to be the same size as your desired canvas.

Oh, and you can determine the amount of paint used by weighing your canvas (the 10 x 10 cm) one before and after painting. The difference in weight is the amount of weight added by the paint. Multiply that by 400 and you will have a good estimate for the amount needed.

Experienced carpenters add 20% for wastage. Carpenters are smart, they know things will go wrong.

So a safe number would be 480 times the amount.

400 x 1.2 = 480

How much actual paint could this be?

Let's say, it takes the artist the equivalent of a quarter of a 2 fl. oz. tube of paint to cover the 10 cm^2 canvas. That's 0.5 fl. oz. of paint to do the painting with.

0.25 x 2 fl. oz = 0.5 fl. oz.

Since the 2 m^2 canvas is 400 times bigger than the 10 cm ^2 canvas you would need a total of 200 fl. oz. to do the same painting as your test piece on the larger size canvas.

0.5 fl. oz. x 400 = 200 fl. oz.

That means you would have to purchase 100 tubes of the 2 fl. oz. paint tubes.

100 x 2 fl. oz. = 200 fl. oz.

Now I did say you need to account for wastage. Assuming 20% of your paint gets wasted. then the number of tubes needs to grow by 20%. That's 120 tubes of paint.

100 * 1.2 = 120 tubes of 2 fl. oz paint tubes.

Now lets say those 2 fl. oz. paint tubes cost $10 USD each. To buy 120 tubes at $10 USD each would cost you a total of $1200 USD.

120 * $10 USD = $1200 USD.

That's $1200 in paint alone.

The next time you go to a gallery show and see all those large paintings hanging on the wall know that the artist had to shell out a hell of a lot of money out of their own pocket to get those paintings made.

The greatest investment artists make are in themselves.

John Vukelic
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  • I was able to price 32 oz jars of student-grade acrylic for about $22 USD apiece. That'll put the purchase at about $150 for your volume estimates. –  Jul 16 '16 at 03:30
  • 200 fl. oz. needed / 32 fl. oz per jar = 6.25 jars needed.

    But you can't buy a quarter of a jar.

    .25 x 32 fl. oz = 8 fl. oz.

    8 fl. oz. needed / 2 fl. oz. per tube = 4 tubes needed.

    Total cost now

    6 jars x $22 USD = $132 USD Plus 4 tubes x $10 USD = $40 USD

    Total is $172 USD for 6 jars and 4 tubes.

    But what about the 20% wastage?

    200 fl. oz. x 20% = 40 fl. oz.

    40 fl. oz. can be made up by buying 1 32 fl. oz. jar and 4 2 fl. oz. tubes. This adds an additional $62.

    $22 + (4 x $10) = $62

    Total cost for 200 fl. oz. plus 20% wastage is $234.

     – John Vukelic Jul 16 '16 at 08:51
  • By shopping around you saved yourself $966 dollars.

    $1200 - $234 = $966

    That's 80.5% off the original price for the needed paint!

    ($966 / $1200) x 100% = 80.5 %

    Which means you can (1) sell the painting for $966 dollars less than you originally though or (2) you can keep the price the same and put an additional $966 in your pocket or (3) the savings gives you some negotiation room when dealing with the customer on the sale.

    Shows what your return on investment can be by just shopping around.

     – John Vukelic Jul 16 '16 at 08:53
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    That math doesn't add up. 240/32=7.5. So, 8@$22 =$176+tax. You don't buy 4 2oz tubes at $10 when you can get 32oz at $22. You pay less, buy the extra. The price will vary on supplier, regardless, but I wanted to point out that $1200 is unlikely unless they're using a lot of different colors are really high grade stuff (which I wouldn't recommend for someone new, even though I don't paint) –  Jul 16 '16 at 08:59
  • 7 jars and 8 tubes is 240 fl. oz of paint. 7 jars costs $154. And 8 tubes costs $80 giving a total of $234. But if we buy 8 jars that's more paint than needed and it saves you an additional $58 because 8 jars would cost $176. You just saved me $56 bucks! Thanks! – John Vukelic Jul 16 '16 at 12:46
  • great calculations. thanks! I was also thinking of buying a gel medium to get more out of the paints. Although i think i would need to buy mid-high quality grade paints in order to retain the color quality with the medium. Not sure now how much paint vs gel i should buy though. – Arturino Jul 17 '16 at 10:29
  • The calculations still hold true for whatever is used to make the smaller test canvas. If you use a quarter of the 2 fl. oz. tube of paint, 1/5 of a cup of gel medium, 1 stick of charcoal, 7 cotton balls, and whatever else is needed to make the 10 cm^2 canvas "all" the items would need to be multiplied by 400 in order to have enough on hand to make the same image on the larger canvas. Do the small canvas first, keep an accurate record of what gets used apply the scaling factor of 400 and you will have a good idea of what will be needed for the larger work. – John Vukelic Jul 17 '16 at 12:10
  • haha yeah that makes sense. matter is matter. unfortunately i dont have the time to do this experiment and have a tiny window to order the right materials for a mule to deliver them to me 4k miles to my remote local. aahh.. 3rd world problems;-) thanks John for your thoughtful post! – Arturino Jul 17 '16 at 22:38
  • Multiplying like this makes small errors into big errors. To avoid that, you'd need to get a very, very accurate initial measurement. ("In theory, there's no difference between theory and practice. In practice, there is.") – Martha Jul 19 '16 at 23:31
  • It sure does! Any mistake at the beginning scales by 400. but if you do the small painting first and you find it doesn't work then you just saved 400 times the expense of making a large piece that doesn't work. But that's just a theory. – John Vukelic Jul 20 '16 at 00:57
  • good luck finding a 32oz bucket of quality acrylic paint for $22! Paint is not cheap, and student grade will lack the intensity and/or purity of hue of professional grade paint. Still it may be the right choice for practice/experimentation. – rebusB Aug 16 '17 at 18:52