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  for Metal Finishing since 1989
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Viscosity of paint and atmospheric temperature correlation

 

Sirs,

In our paint finishing shop, we need to adjust our paint viscosity depending on atmospheric temperature to avoid dry spray, orange peel etc., This viscosity of paint is increased or reduced merely based on experience. Is there any graph or any aid that relates viscosity of paint & atmospheric temperature. You can also help me by providing any references or journals, etc.

P. BHALAJEE
bicycle mfgr. - Chennai, India

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Orange peel, run off/tear drop or paint cannot stay are base contamination defects which comes to surface preparation. Normally when you purchase paints for auto-mobile or aerospace paints you can request from the supplier Technical data sheet. In it the information will inform you of the performance of the finish product and preparation, too.

Example from a Technical data information like :
1) Type of hardener/catalyst and thinner to be used
2) Instructions for use - Mixing ratio - Induction time - Spraying viscosity - Pot life - Dry film thickness
3) Application recommendations - Temperature - Relative humidity - Equipment
4) Physical properties - Dry time - theoretical coverage - Dry film weight
5) Storages of paint condition
6) Safety precautions

This information is a must request or else you will hit problems. Different paint manufactures/paints have different information and cannot use that information for other type of paints.

Hope this help.

TESSENSOHN ALBERT
- SINGAPORE

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Have experiences similar problems. As far as I know there is no such thing as a graph, that will easily help you. Depending on type of paint systems there are a more influences than just the temperature on the viscosity of the paint. Even more important is the humidity in the paint cabin and during the flash off time (in particular running water borne paints).

Find out how the humidity and temperature varies. If the variation is within a considerable big range, the installation of a control system can help. Sometimes just a better air circulation can lead to improved results.

Ines Kistnebrügger
- Germany

Could you please give me information on the most suitable viscosity for spraying paint utilising an air pressured device.

Jonathan Mwailu
- Derby, U.K.

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I have experienced similar problems in our system were the paint supplier is inadvertently making additions to the paint in - order the circumvent the prevailing problems. We have therefore decided to look at it from another aspect, that being to facilitate the area in - order that the required parameters can be maintained.

Brett Dovey
auto mfgr. - Pretoria, Gauteng, South Africa

You should just do a test spray on a non important piece of similar material - metal panel etc. - to check your mix, viscosity etc.

Julian davies
- tamponworth UK
September 24, 2011

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Q. Temperature of paint is 28 °C & viscosity is 28.5.

If increasing temperature what is the viscosity

Sri Raman
paint - Chennai, Tamilnadu, India
October 4, 2013