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Re: [MW:15405] Tollerence for Painting DFT

Dear Mr. Vichare,
 
The required DFT is characteristic of manufacturer and client specifications. Same goes for tolerences. Usually manufacturer provides you with a range of recommended DFT and you select the one appropriate for yourself and accordingly tolerences.
Tolerences are also a characteristic of paint application methodology, airless can give you least variations while brush will give highest. We mark an area of 1 sq. mtr. and take 10 readings and then calculate the average, the average must be above the required DFT value. The variations in readings is a characteristic of your specifications as stated above.
 
I can comprehend two possible reasons for your peel off test failure, either the suface has not been appropriately prepared (it must be rough and smooth) or DFT is much above the recommendation of manufacturer. Please note that if suface is not prepared well paint will not stick to it and will peel off.
 
 
 
Ammar Shaikh

On Wed, Sep 26, 2012 at 12:17 PM, Ramchandra vichare <vicharerke@indiatimes.com> wrote:
Dear Experts;

with reference to the subject referred above please let me advise with documentary evidence about tolerances for  Painted items when DFT is specified. Why paining fail in cross cut/peel-off test(Pl. ref photograph attached)? How to control the same?

Requested to advise

Regards
RK Vichare

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The views expressed/exchnaged in this group are members personel views and meant for educational purposes only, Users must take their own decisions w.r.t. applicable code/standard/contract documents.
 
 

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