[TheForge] food grade coating

[Bruce .]

Here's an MSDS for B/C PermaBlue.  There might be more than one product
under that brand name, so try to find the one you used.  The supplier is
required by law to provide it, which they usually do these days over the
Internet, for you to print off.
https://www.birchwoodcasey.com/getattachment/Resources/Safety-Data-Sheets/13322-13325-Perma-Blue-Paste-Gun-Blue-2012.pdf.aspx

Note that that formulation contains selenium, which probably makes it a
no-no for food use.  (That's not a certainty, because it may be that the
selenium residue on the surface would be lower than the legal threshold,
whatever that is.  Bad bet, though.)

I'm not knowledgeable in the field either, but if a glossy brown or black
finish would do, then I recommend the one finish that's generally regarded
as safe for food:  A thin coat of polyunsaturated oil, followed by heat
(350 - 400 F for an hour works).  If the metal is shiny, this will be a
deep cocoa brown which often looks ugly.  If the metal is black, it will be
a lovely shiny black.  The shine could probably be rendered to matte easily
enough.  Unfortunately, this is not a hard finish and will scratch.

I note there's a discussion of this topic on Iforgeiron.com, but I didn't
read it.  There's a lot else accessible through Google.  It's a real can of
worms to be working with surfaces for restaurants.  There are specific FDA
regulations.  You don't say whether these are food preparation surfaces, or
what.  I wouldn't touch something like this without a sign-off from my
attorney and a check what my insurance will cover.

Have you considered covering the surface with a transparent, food-grade
plastic sheet, such as acrylic or polycarbonate?
http://www.professionalplastics.com/professionalplastics/FoodProcessing-HandlingBrochure2011.pdf

Bruce
NJ


On Tue, Jun 24, 2014 at 5:08 PM, Wayne Ackman <stryker at vulcanpro.com> wrote:

> I've been working on a restaurant.  Made them some metal countertops that
> they wanted to have blued.
> We used PermaBlue, which turned out decent.  I then sprayed a couple coats
> of urethane on the counters.
> The restaurant hasn't opened yet, but someone spilled something (soda
> supplies?) on the counter and it
> ate right thru the finish.  This has opened the concern about what kind of
> coating we can put on the counters
> that would furnish a food grade finish.  Has anyone done this?  And have
> any suggestions?
> Thanks for any help.
>
> Wayne
>
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