Protecting an Alluminium edge

[RickH]

On a boat dash I need to fit an extra display dial.
There is an existing aluminium frame, used for non-purchased GPS plotter accessory, they fit a sunglasses holder/ oddment tray behind it.
I have had a black plate CNC machined, carbon fibre finish printed, and filed out a segment to allow the display gauge to fit …
The Plate & fitted gauge show here:
https://www.4shared.com/s/flrk4SqFXiq

The segment I filed out, has of course lost its protective coating, so need to apply something to the edge to prevent the Ally plate going crusty in salt air.
Ideally it should be Anodized, but I can’t get just the edge done, and don’t want to lose the nice trim features.

Although not readily visible having it black would be an advantage, just so there is a shadow line.

Anybody got a thought on what product I could use …… not easy to spray as the stepped ‘sliver’ trim would not be easy to mask.
Thinking there may be something I could apply with artist brush or cotton bud …… any suggestions.?

 

[just pumps]

Put it up as a jpeg photo, no way am I downloading it.

 

[RickH]

Sorry, there wasn't an option to save word doc as a jpeg ..... as you asked for this have found a pdf to jpeg conversion (though quality drops a lot)

 

[Tigercubrider]

Basic black paint? Even nail varnish might work

 

[just pumps]

Black paint, spray some into the lid then apply with a tiny brush.

 

[RickH]

Thought about a black paint ... I have some Hammerite Smoothrite or Plasti-Kote flat black.

Also have Rustins Transparent lacquer, I could put over it.
Or even have a can of Alloy Wheel clear coat.

Thoughts on either of these ..

 

[just pumps]

External in salt water areas it has to be the Hammerite for me.

 

[RickH]

I thought that may be answer ... pity as Plasti-Kote paints out perfectly flat, but I have no idea if it is suitable for external use .... web site seems non-commital

 

[just pumps]

Test it on something then leave outside as a rough guide

 

[RickH]

Don’t have that luxury have to fit panel in the boat this w/end so need to paint in next 48Hrs.
I’ll go with Hammerite Smooth black.

 

[RickH]

Bad news ... all my tins of Hammerite (smooth or hammer). Are the ‘Direct to rust’ product. This is specifically stated as suitable for Ferrous only.
For bare Aluminium you have to use ‘Direct to Galvanised’ product. (Which I don’t have)

Seems nuts to spend on another whole tin so such a small piece ..... I’ll see if there is a paint pen that works on Alluminium.

 

[foxhole]

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