Model Boat Mayhem

Technical, Techniques, Hints, and Tips => Painting, Finishing and Care. => Topic started by: Martin (Admin) on October 07, 2017, 03:36:53 pm

Title: Repainting metal?
Post by: Martin (Admin) on October 07, 2017, 03:36:53 pm: Any suggestions how I prep something like this for respray a different colour please? :-)
Title: Re: Repainting metal?
Post by: Netleyned on October 07, 2017, 03:48:27 pm: Plastic Primer IMHO
Ned
Title: Re: Repainting metal?
Post by: Martin (Admin) on October 07, 2017, 03:56:33 pm: It's metal, does that matter?
Title: Re: Repainting metal?
Post by: Netleyned on October 07, 2017, 04:04:45 pm: Sorry Boss,
Looked plastic.
If Metal ask Mr Jones %)

Ned
Title: Re: Repainting metal?
Post by: TailUK on October 07, 2017, 06:55:11 pm: That looks as if it's an anodised surface, which is good! Anodising makes the surface of Aluminium impervious to oxidisation and is also slightly porous so it should accept regular automotive primer and paint easily. You could use a zinc chromate or etch primer if you wish but it shouldn't be necessary.
Title: Re: Repainting metal?
Post by: T33cno on October 07, 2017, 07:15:20 pm: They're ten a penny on eBay just buy another colour {-)
Title: Re: Repainting metal?
Post by: Martin (Admin) on October 07, 2017, 10:07:21 pm: Quote from: Martin (Admin) on October 07, 2017, 03:36:53 pm

..... "something like this".... ok2
Title: Re: Repainting metal?
Post by: Stavros on October 07, 2017, 11:07:49 pm: Right then....tried to do this myself as i was cheesed off losing mine in the workshop and failed....even using a proper etch primer...it peeled off. I think there is some form of silicone type of substrate in the anodising and paint doesn't like to stick to it.... yes initially it wil look good but it some peels off and then the torch looks pants. Bearing in mind i used proper car paints and not aerosols.

Dave
Title: Re: Repainting metal?
Post by: derekwarner on October 08, 2017, 01:51:05 am: Yes......some things in life just don't appear practical or simple......& as Dave says.....

"some form of silicone type of substrate in the anodising and paint doesn't like to stick to it"

May only be a few micron in depth, but to totally remove the anodised oxide surface, a complete abrasive blasting may be required.......[these day's plastic bead blasting seems popular O0]....followed by an ultrasonic fluid bath <*< ......then an aluminium/zinc rich primer........[Yellow Chromate?]

Derek
Title: Re: Repainting metal?
Post by: Martin (Admin) on October 09, 2017, 06:21:46 pm: OK, thanks lads...... well obviously I'm gonna have a go anyway.... why let reason and logic get in the way of a stupid idea?! %%
Title: Re: Repainting metal?
Post by: nemesis on October 10, 2017, 04:53:28 pm: are they still using zinc chromate I thought it was discontinued with phosphates coming along. nemesis
Title: Re: Repainting metal?
Post by: derekwarner on October 10, 2017, 10:11:09 pm: I still have a small tin of Yellow Chromate nemesis ....that I acquired/borrowed many years ago..........I last thinned it down maybe 10 years ago......amazing how older [no good for your health] paints can be....the tin still bears a MIL - Spec reference so I suspect it was sourced from the American Military %)
Title: Re: Repainting metal?
Post by: Martin (Admin) on October 14, 2017, 05:18:31 pm: OK...... Attempt No. 1

1. Throw patience and common sense straight out the window.
2. Turns out, some parts are plastic.
3. Cleaned down all the parts with Colgate Whitening toothpaste ( used as a scrubbing abrasive!? ).
4. Effective but ages washing off the toothpaste!
5. Wash down with soap.
6. Ages washing off the soap.... Dry.
7. Light coating with grey primer, non-plastic type.
8. Looks OK.
9. Second coating of grey primer.
10. Still looks OK.
11. Spray with matt white finish coat.... craters, pin-holes, dewetting, fish eyes, static! >>:-(
12. Second coating of grey primer.
13. 1st coat of bright fluorescent Red finish.... Looks Totally Terrible.
14. On Amazon, order paint stripper. :embarrassed: