Issues/questions with Alclad II Black Gloss Base

[CottonFX]

Hi everyone,

I am by no means an expert painter.. but I have recently decided to try the Alclad II brands of paints to achieve some polished metal finishes on a star trek prop that I am building now. Yesterday I did my first attempt at applying Alclad II black gloss base so that then I can apply the Alclad II aircraft aluminum paint to it (which requires that base cause its polished.)

Honestly it was a disaster, aside from spilling the black gloss on my work table (dumb mistake on my part, that little rubber thing inside is NOT a dropper LOL,) I ended up applying it all wrong and got a gritty looking mess of a surface which I guess is called dry spray. I figured this had to do mostly with me using the airbrush as if it was a spray can and moving it too fast along with maybe not sanding my primer smooth enough.

I decided to sand it smooth again and try a 2nd time.. this time I sanded the blemishes with 400 grit then went over it with 600 grit to get a pretty smooth finish.

Here is where the question i have comes in. Although my surface was smooth and nice to the touch, it did still have some visible sanding marks that comes along with dry sanding on it. I have painted with black spray paint before and I feel strongly these marks would have been completely fine and covered by the spray paint and based on previous experience, I would have had a very glossy surface.

Well, although attempt number 2 was better than 1 and the application was done correctly this time... I do have a glossy base but all of the visible scratches and sanding marks are visible throught the black glass base coat which makes me a sad panda.

Now before anyone says, "throw the alclad black gloss base in the garbage cause it sucks..." please don't. I spent the money on this alclad paint so I really want to make it work.. however I think in the future I may go with a different process to create the black gloss surface before applying the metal paints. I'll probably do automotive primer with a clear coat next time.

I am left with it seems only one choice.... wetsand at 600 grit before applying it again and hope that the wetsanding will leave a better surface than drysanding that wont show through the base.

Not sure whether anyone would suggest polishing the wetsanded surface with polishing compound or scratch/swirl remover before but I know that people have told me alot that 600 grit is about the highest you should do for paint to still adhere to the surface.

Can any experienced people give me some pointers on how to proceed? Thanks all.

 

[bookface]

You can try going a little heavier with the application, or do more coats. Honestly though I'd probably go higher on the grits, at least 1200 with wet sanding. I use the black base a lot, but not so much as it was intended as I don't often follow it up with the metallic finished. I think possibly the last time I followed it with alclad chrome I went to 2500 before applying the chrome. The chrome went on fine. The metallics are not the most wear resistant of finishes at the best of times, so if you're going for looks then I'd say wetsand much higher and see how it goes from there.

 

[CottonFX]

You can try going a little heavier with the application, or do more coats. Honestly though I'd probably go higher on the grits, at least 1200 with wet sanding. I use the black base a lot, but not so much as it was intended as I don't often follow it up with the metallic finished. I think possibly the last time I followed it with alclad chrome I went to 2500 before applying the chrome. The chrome went on fine. The metallics are not the most wear resistant of finishes at the best of times, so if you're going for looks then I'd say wetsand much higher and see how it goes from there.

Hi thanks! One thing though...when u say wetsand using a higher grit, do you mean right before applying the metal finish? I was actually hoping to get another coat of black gloss base to go on smooth like it's suppose to without having to wetsand before the metal paint. I was thinking of wetsanding the current black gloss then doing another coat of black gloss hoping it would look right this time. Most likely now, if I wetsand I will have bare spots anyway because of having one coat..especially near edges.

Would you still do 1200 in that case and reapply the black gloss?

 

[bookface]

I would recommend experimenting with both, though one coat probably isn't enough. Try on a scrap piece of plastic with wet sanding right before applying the metallic, and then on another spot try wet sanding and then reapplying the black, then the metallic. If you want to do it the second way and apply the black without wet sanding, it will need to look glossy as soon as you apply it, so if it doesn't you aren't putting it on heavily enough. Of course, the heavier you put it on the higher the chances of getting a run in the paint. Experimentation is the key to getting to result you want.

 

[CottonFX]

Well, I just wetsanded with 600 grit then 1000 (they don't have 1200 at my auto parts store) and then reapplied the black gloss. Still has weird areas showing up. The application is going on better and I'm applying it in passes and correctly it's just resulting in stuff that I can't see or feel, somehow showing up after the black gloss application.

It could be contaminates again but I dunno. I am about at the decision that this alclad black gloss base is crap and I think I am going to switch to a black primer with a clear coat before applying the alclad metal paint. I feel like even black gloss spray paint will result in a thicker and cleaner layer than this stuff as thin as it is.

I'll be using black rustoleum automotive primer probably with rustoleum crystal clear enamel on top. Hopefully this yields a better result.