Scuffing paint...

[Oberstar]

For those of you who have used Rustoleum's Rusty Metal Primer in a can, is it necessary to 'scuff' the paint with a red 3M pad before topcoating?

The situation is that all small metal parts have been bead blasted, and because my work schedule is sporadic, I have started to spray bomb the parts with Rustoleum spray can primer. Before I can topcoat with an oil based enamel that is compatible with the Primer, it will be a minimum of 2 weeks, so the primer will have fully cured by then.

When I return, can I go straight to topcoating?

[MackTheFinger]

It's your call but I'd scuff it. The slicker the primer the better the paint will look. Rustoleum primer takes a long time to dry. Two weeks sounds about right.

Edited May 18, 2017 by MackTheFinger
speling

[Plymouthy Adams]

any paint primer or top coat be it a conversion wash will ALWAYS adhere its best with sanding.  Follow the direction on the can, it tells you how to prep for application.  Further info in on their website and a very much recommended read.  While it is an excellent first layer on metal, it is not the choice of body shops as they cannot wait days to go to the next step so ie the body shop high dollar primers for in by 8 out by 5 production.  Though some high end restoration shops will use it and take the time to allow it to do its magic.  Do allow for proper drying in the process prior to any top coat or sanding of this primer.  The fish oils in the mix convert rust...if no rust and on seasoned paint or clean metal, the oil has to evaporate to the surface.  Depending on temp and humidity, this could take a few days in good dry air with circulation down to 10-14 days if humid dark with little air exchange shop/building.   This process can be sped up with spray application, thinning to proper viscosity using a high end enamel reducer, use of other lower grades reducer I cannot recommend no account for in their application and drying process. 

[MackTheFinger]

I've painted a bunch of cars and even more motorcycles and I can't tell the difference from one reducer to another other than fast or slow. I'm pretty easy going, though   Paint, primer, sandpaper, tape, everything else is a different story. I generally use Dupont products, now Axalta; starting with lacquer primer and paint through Dulux and Centari. I didn't like the 2 stage stuff at first but have come around.  PPG and HOK are okay but I'd stay away from the really cheap stuff. I've tried cheap paint and primer and there's a reason it's cheap. I use 3M tape, sandpaper, etc although sometimes I'll cheap out on DA paper. Too much work to have to do it twice.. 

[Plymouthy Adams]

1 hour ago, MackTheFinger said:

I've painted a bunch of cars and even more motorcycles and I can't tell the difference from one reducer to another other than fast or slow. I'm pretty easy going, though   Paint, primer, sandpaper, tape, everything else is a different story. I generally use Dupont products, now Axalta; starting with lacquer primer and paint through Dulux and Centari. I didn't like the 2 stage stuff at first but have come around.  PPG and HOK are okay but I'd stay away from the really cheap stuff. I've tried cheap paint and primer and there's a reason it's cheap. I use 3M tape, sandpaper, etc although sometimes I'll cheap out on DA paper. Too much work to have to do it twice.. 

REDUCERS...yes......but we are talking about a product that the factory that makes it does not use enamel reducers but instead other solvents.  It is these distillates that I do not use nor recommend...use whatever you are comfortable with.....it was only a report on what works for me...I do not like mineral spirits and auto body work...where are you buying Centari...it has been discontinued and NLA for years...

Edited May 19, 2017 by Plymouthy Adams

[MackTheFinger]

I should've said I can't tell the difference between brands of reducers. It seems obvious that types aren't interchangeable. I also didn't mean that I use Centari now but that I used it extensively in the past. Using base/clear like everyone else now. 

edit  to add:

I actually did paint a '73 Harley dresser with Centari last year. I had about a quart of garnet metallic Centari left from something I painted back around 1990. Even after setting on the shelf that long the paint laid down well and turned out perfect. 

Edited May 19, 2017 by MackTheFinger
content

[dale]

If you get Rustoleum primer on too thick it will crack and you will have to sand it down to the metal.. Trust me Ive done it.  I suggest not using it.

[Plymouthy Adams]

8 minutes ago, dale said:

If you get Rustoleum primer on too thick it will crack and you will have to sand it down to the metal.. Trust me Ive done it.  I suggest not using it.

that is why the makers always list their specific instruction for proper use.....

[55 Fargo]

I just primered 1 of the kids 66 Acadian.

First stripped ithe 3M stripping discs then used DAand a palm sander.

I much prefer Norton papers.

I use straight xylene or acetone even used a bit of lacquer thinner a few times. 

You don't need special enamel reducer necessarily.

I have also added hardener to alkyd rust primer dried and cared faster.

I used Tremclad red oxide primer cut it 25 to 30 % xylene.

This stuff flashed and dried fast shot out of a cheap gravity feed gun 1.5 tip.

Next time I use this stuff plan to use a cheap help with 1.8 tip.

 

Edited May 19, 2017 by 55 Fargo Spitfire

[dale]

I might add that for painting the small black parts that Rustoleum makes a black appliance epoxy type paint in a spray can that dries really hard.

[Plymouthy Adams]

29 minutes ago, dale said:

I might add that for painting the small black parts that Rustoleum makes a black appliance epoxy type paint in a spray can that dries really hard.

while I have used this on an automobile way back in 1969, I can attest to its 'wears like a pigs nose' quality..thanks for reminding the forum of other paint options...

[55 Fargo]

Tremclad Red Oxide Primer after 1 week, sand off easily blocks nice..

This product is manufactured by the Rustoleum corporation in Canada direct to rusty metal alkyd primer..