Paint Audits Prevent Problems

July 11, 2014

Categories: News, Paint Audit, Paint Problem, Uncategorized

A quick paint audit can keep you from getting caught by the cold.

Each fall we get numerous calls asking, “Have you changed the paint?” The caller often explains that the paint isn’t drying it like it use to. We are always happy to check our batch samples to be sure that nothing had accidentally changed but the answer to the problem usually relates to one of two factors:chicagoy weather sm

  • A change in application conditions – temperature and humidity, or;
  • A change in the application procedure that creates greater film thickness or slower drying times. Factors are larger spray tips and/or higher pressures that cause heavier film builds, or faster conveyor or line speeds that allow less time for the wet paint to cure.

Now is the time to conduct an audit to prevent getting surprised when the weather changes. We will identify the critical steps in your finishing process and set quality assurance standards for each.

  1. Surface preparation –cleaning, profile, etc.
  2. Equipment set up – tip/nozzle, air/fluid pressure, etc.
  3. Paint preparation – mixing/thinning, viscosity
  4. Application – spray technique – edging, spot-priming, etc.
  5. Application rate – wet-film-thickness/ dry-film-thickness
  6. Drying/curing requirements and conditions
  7. Handling/assembly or pack-out procedures

It’s a good practice to have a paint audit conducted annually or whenever there is a significant change in the materials, procedures , workers or weather. Carbit’s experienced Project Managers perform free paint audits as a way to introduce ourselves and as a service to help you preempt problems before they occur.

Written by Bob Lyons, Carbit Business Development

Download printable version: Paint Audit_News


How To Dry Paint Fast

June 30, 2014

Categories: Coating Solutions, Infrared cure, News, Paint Problem

Our customer’s often ask, “How can I dry paint faster?”, but what they really want to know is:

  • How fast can I handle the part?
  • How fast can I package the product?
  • How fast can I ship the product?

Handling, packaging and shipping products with paint that is not fully dry and cured can lead to many problems.

  • Complaints caused by missed shipping dates due to waiting for paint to harden.
  • Rejects and returns due to parts sticking together or sticking to packaging materials.
  • Loss of goodwill due to poor coating appearance.

BGK Infrared Oven

It is generally recognized that time and temperature affects the rate of most chemical processes, including the drying and curing of paint.  For example, higher temperature for a given length of time generally results in faster drying and curing of a paint.

Predicting the amount of heat and the length of time required to dry paint faster involves several variables:

  1. The type and weight of the part being painted.
  2. The type of coating.
  3. How the heat is generated and transferred to the coating.
  4. The ability to measure the temperature of the painted part.
  5. The ability to maintain a constant temperature.

Carbit Paint Company in Chicago can help determine how to dry paint faster through the use of its BGK Infrared Smart Oven.  This oven has a microprocessor that links fast response, short wave infrared emitters to internal pyrometers (thermometers) that measure the temperature of the painted surface. The combination of fast emitter response and measurement of the part temperature provides a constant temperature for a specified period of them.  This control allows exact correlation between time and temperature and will answer the question, “How can I dry paint faster”.

By Bob Lyons – Business Development

Download printable version:  Dry Paint Fast_News


Infrared ovens force-cure industrial coatings

June 22, 2014

Categories: Coating Solutions, Infrared cure, News, Paint Problem

I’ve previously commented that uncured paint often delays shipments or results in complaints when customers unpack their products and discover damage. Fortunately, infrared ovens can force-cure coatings and eliminate these delays and complaints.

Predicting delays or complaints can be as difficult as predicting the weather, which in fact has a lot to do with the problem.  One day the paint is dry and hard. The next day it remains soft and sticky.

To understand the problem, it is helpful to make the distinction between “drying” and “curing” of a coating.  A coating is dry when the carrier (water or a solvent) evaporates and leaves the paint.  At that point, the paint is dry-to-touch and can be handled. Curing is more complicated and occurs when the resin in the coating forms a solid film. The curing process generally takes longer than the drying process and is very dependent on temperature.

Most coating performance properties require that the coating be cured, not simply dry. For example, film hardness, blocking resistance (surface defects from early coating contact with another surface), chemical, moisture, and abrasion resistance are achieved only when the coating is fully cured.

Understanding the distinction between drying and curing helps explain why complaints are more common in cool weather. The coating may feel dry-to-touch, but it is not fully cured and hard. Surface defects occur when the parts stick together or are prematurely damaged by contact with packaging materials.

The classic answer to this problem is to switch to a coating that requires baking the coating in an oven to “cure” it. Bake coatings can be liquid or powder, and will form a film only when exposed to high temperatures, usually 300° – 450°F.

Portable Infrared Oven

 A less expensive option is to add a heat source to force-cure a coating that would otherwise dry and cure by itself if given sufficient time.

This can be done efficiently by adding infrared (IR) heaters in the process line to force-cure the coatings to allow for fast and problem free shipments.

Infrared offers many advantages over convection ovens:

  • Increased line speed through-put
  • Lower utility costs – energy savings
  • Shorter overall cure time
  • Shorter conveyor length requires less floor space and investment
  • Less work in process
  • Infrared modules can be portable and adjustable
  • Lower carbon emissions
  • Less air movement and therefore less dust in the air
  • IR introduces less heat into the work environment.

Paint manufacturers, like Carbit Paint Co. in Chicago, have programmable IR lab and conventional baking ovens that can help determine whether a conventional baking system or force cure systems with infrared will best prevent delays in shipments or complaints due to under- cured coatings.

By: Bob Lyons –  Business Development

Download printable version:  IR FORCE CURE_News


High-Hiding Paint Colors

August 19, 2013

Categories: News, Paint Problem

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High-Hiding Paint Colors

The choice of a paint color affects the total cost of a product in many ways. The reasoning goes beyond the simple cost of the paint itself. Often times, it has to do with the whether or not the color is a high-hiding paint color.

It is generally recognized that some paint colors cost more than others. For example, a ruby red 2014 Ford Focus SE costs $395. This is more than any other available color. There are several reasons for this.

The basic reason stems from the cost of the pigments used to create a color. Common pigments used in industrial product coatings range in price from $1 to $30 per pound. Bright reds and yellows can be very expensive and tend to be on the higher end of that scale.

A second factor, and one that is sometimes overlooked, is the difference in hiding power, or opacity, of different paint colors. Black for example, is considered a high-hiding paint color. It completely hides most substrates in a single coat, while a bright yellow or red may take multiple coats to get full coverage.

Obviously, the economics of applying more coats goes far beyond comparing the cost per gallon. But even among comparatively poor hiding colors, like reds and yellows, difference in the hiding power can exist because of how the paint is made.

High-hiding paint colors are made by mixing dry pigments in the factory, not by adding liquid colorant to tint bases. The difference between the two approaches is illustrated in the photo below.

 

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Even though the two yellows are identical, the one made with high-hiding dry pigments covers the black and white card much better than the paint made with liquid colorant. (Both paint paints were applied at the same thickness.)

Clearly, the total cost of painting can be reduced by using high-hiding paints made with dry pigments mixed in the factory.