PA GOVERNOR’S INSTITUTE--2005
Mixing Paint
Math-in-CTE Lesson Plan
Lesson Title: Mixing Paint
Lesson Number: 36
Occupational Area: Auto Collision Tech.
CTE Concept(s): Automotive Refinish
Math Concepts: Using Ratios
Lesson Objective:
Supplies Needed:
Given the lesson on mixing paint, students will use ratios to determined amount of paint, reducer, and
hardeners to use for a given amount of paint as for man. Specs.
Mixing cups, Mixing sticks, P. sheets, Pint cans, Quart cans, Gallon cans
THE "7 ELEMENTS"
TEACHER NOTES
(and answer key)
1. Introduce the CTE lesson.
Today we are going to work on the first thing that we need to do to take
the paint from the can and applying it to the car.
The lesson can be used with any paint manufacture,
Dupont, PPG, etc.
In previous lesson we talked about how some paints where put on hot
plates and sprayed hot.
Today most paint systems need other additives put into the paint to
make them function the way we want (have high gloss, corrosion
protection and color match).
To do this, manufacturers use ratios to mix the paint so you can apply it
with a spray gun to the car.
2. Assess students’ math awareness as it relates to the CTE lesson.
Remember, how many ounces in a pint? … quart? … gallon?
Make sure that you ask your students the relationship
between the units, because if they do not know, you will
have to tell them.
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PA GOVERNOR’S INSTITUTE--2005
Mixing Paint
3. Work through the math example embedded in the CTE lesson.
PPG Base coat system DBU has a mixing ratio of ….1:1
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2
That is 1part paint to 1 ½ parts reducer. If you are mixing one pint of
DBU(16oz.), how much ready-to-spray paint are you going to have to
work with?
2. DCU 2042 clear uses a mixing ratio of 4:1:1, how much sprayable
clear will you have if you mix a quart (32ozs.).
4 parts clear : 1 part reducer : 1 part hardener
32/4=8
Your students are going to ask you what a part is, that is
like asking how many licks are there in a tootsie pop. It
can be any number you want to use.
16oz + 16oz + 8oz = 40oz
1.5 quarts
ratio: 32:8:8
32oz. Clear, + 1 part of reducer or 8oz. + 1part of hardener or 8oz..
32+8+8=48oz
If your students are having problems with this, draw
equal lines on the paint can so they can see 4 parts.
1.5 quarts of sprayable clear
4. Work through related, contextual math-in-CTE examples.
DX 579 metal prep uses a mixing ratio of 1:2. How much DX 579 will
you have if you are mixing one gallon?
This is not mixing paint but it works the same way.
1 part 579 + 2 parts water= 3 gallon of metal prep
5. Work through traditional math examples.
Have your students mix the orange drink for their shop party.
The orange drink has a mixing ratio of 1: 5, and they are mixing 5
gallons for the party. How much total orange drink will they have?
1 part orange drink + 5 gallons of water= 6 gallons of
orange drink for the party.
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PA GOVERNOR’S INSTITUTE--2005
Mixing Paint
6. Students demonstrate their understanding.
Have your students mix paint for the cars that you are working on in
your shop.
This is where I would use the mixing cups and sticks, but
not until the students showed they understood how they
worked. For this use water first - it is cheaper than paint.
7. Formal assessment.
Check the student’s work for the right answers. You will
know if they are getting this. They will not be able to
paint if they do not.
Put several problems on a test. Worksheets may also be used.
Adaptations for special needs students.
Drawing equal lines on the paint cans should help students who
have a problem understanding. This can also be done on the
mixing cups and sticks.
Give the student extra time.
Teacher Notes:
Math Standards and Assessment Anchors addressed with this lesson.
M11.A.1.1.1, M11.A.2.1.2, M11.A.2.1.3, M11.A.3.2.1, M11.A.3.2.2
References.
PPG P-sheets, Student text book
Author(s):
John H. Fuller
Kurt Speicher
Carol Appleby
Bonnie Campbell
Eric McGuirk
Position:
Auto Collision Instructor
Auto Tech Instructor
Math Instructor
Special Ed Instructor
Guidance Counselor
School:
Crawford County VoTech School
Crawford County AVTS
Dauphin County Technical School
Greene County CTC
Crawford County AVTS
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