Re: [MW:7867] Surface preparation and coating

Dear Mr.Sundaram,

If Profile is more than Required DFT (First Coat) ,then it will be a problem as Mr.Gole Said.

Hence Better to Control the Surface profile or Refer Paint Manufacturer data sheet to provide the increased DFT of first coat.

And Regarding, exceeding DFT of required one, it can be 20% plus or Minus.

Thanks.

Piramarayan B

On Wed, Oct 27, 2010 at 10:33 AM, Sundaram Sundaram <nss2410@gmail.com> wrote:

Thanku for your reply Mr.Gole.The primer DFT- 75microns,midcoat coat- 75 microns,final coat- 75 microns.overall 225 microns.Most of the times the total DFT is exceeding 225microns and how to control this.Can you give some more clear picture,pls

On Wed, Oct 27, 2010 at 11:15 AM, BHARAT GOLE <bharatgole@hotmail.com> wrote:

If surface profile is more than acceptable limit then it may cause for rust rashing i.e high peaks may expose after paint curing/contraction will be rusted.
Actaully it depend upon the so many factors such as whole paint syetem and DFT etc

Bharat B. Gole

> Date: Tue, 26 Oct 2010 22:58:41 -0700
> Subject: [MW:7857] Surface preparation and coating
> From: nss2410@gmail.com
> To: materials-welding@googlegroups.com

>
> Dear friends,
> Blasting Grade required - SA2.5
> Surface profile required - 40 - 70microns
>
> If the surface profile crossing the required limit 70-
> 80microns then what will the effect on painting and what is the
> reference code.Please guideme
>
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