[DavidHawke]

Hopefully someone can help shed some light on this for me...

I have received several samples of high-grade pearls and Eckhert fine bright aluminum powder (yes I know it can be dangerous, I've been warned) for use in automotive paints. I am planning to start testing them in a few experimental screen paint blends. However, for sake of consistency it would be easier if I can first add the powders into a clear medium (Valspar Clear protector is what Harpmaker said he likes, any other suggestions are welcomed).

So my question is...
Is there any typical ratio of powdered reflectives to fluid carrier, that is used in the craft paints?

I would guess 1/3 to 1/4 quarter of the fluid volume is composed of solids... but obviously that is clearly a guess. Does anyone have any solid info that might help clarify this? Past experience perhaps?

 

[Harpmaker]

Actually David, I generally prefer to use Liquitex Matt Medium as a clear medium, but the Valspar Clear Protector would be my next choice and it's quite a bit less expensive than LMM. I like LMM because it is designed to be a colorless clear from an artist's point-of-view and one that doesn't yellow over time. I don't know that the same could be said of the VCP.

Taking a closer look into the various clear mediums available has been on our To-Do list for some time, but other things come along that we simply consider more important (like C&S International).

Adding your powdered agents into a clear medium could be quite a project. Back when we were testing the possibility of making our own aluminum paint one of the things that we found out is that even commercial aluminum paint manufacturers don't start with aluminum powder, but rather use aluminum paste. The problem with trying to mix a fine powder into a fluid is that the powder will tend to clump. When this is done, say to make the aluminum paste, the mixing is done ultrasonically as well as mechanically.

If I were to try to do this I would add VERY small amounts of powder (like from a salt shaker) while constantly stirring the liquid.

If I remember rightly I think the high quality aluminum paints contain something like 40%-50% aluminum by volume. As for pearl paints, I don't have a clue! A good place to start would be to find some MSDS info on some existing brands; and Technical Data Sheets would be even better. Sometimes they give the proportions of ingredients and sometimes they don't.

I think your proportions of 1/4 to 1/3 by volume would be a great starting point!

As for your thread topic "grams to fl. oz.", there is no set conversion factor since both powders and fluids have different weights depending on what they are composed of. I just got 4 fl. oz. of Sophisticated Finishes 'Iron' Metallic Surfacer and it is HEAVY! It weighs almost 10 ounces! That is much more than any other paint I have ever tested. The reason is it contains a LOT of real powdered iron.

 

[DavidHawke]

Thanks! Sorry to misquote you, on the clear medium. Do you think Michael's sells the Liquitex Matte Medium?
I tried adding some powdered xyrellic to a small batch of Scorpion, and it did exhibit a little bit of clumping. However, I was working with a small fluid 2oz batch, in a 4oz bottle. I was simply vigorously shaking it. It almost dissolved the clumps, but not 100%. When I mix more powder into solution, I guess I'll have to do it in a large enough batch to used the drill end mixer. Maybe 1/4 to 1/3 of a quart at a time. I'll play around with the ratios to see what works. If it is too concentrated with powder, I can always gradually add more clear to the mix until it seems about right.

The xyrellic looks alot like the paintonscreen sample, once its added into gray latex paint. From the looks of it, I'd say its pretty likely that they are using xyrellic or something pretty similar.

I haven't seen that sample yet in the mail. Are you done with it yet? No hurry if you're not... just wondering. What did it look like under the microscope?

 

[Harpmaker]

Thanks! Sorry to misquote you, on the clear medium. Do you think Michael's sells the Liquitex Matte Medium?

No problem David, the fault was totally mine since I don't think I even mentioned LMM to you (sorry for the shorthand, but it's something we do to save having to type out all these long names of stuff ). In the early development stages I see nothing wrong with using VCP or Behr Faux Glaze, but for the real deal I like LMM.

Yes, most Michael's stores that I have been in sell the Liquitex Matt Medium. Unless they are having a sale they do charge retail prices which can be downright painful! If I know I want to buy a large amount of one Liquitex item, or a lot of small items, I usually order from dickblick.com since they sell Liquitex stuff for up to 50% off retail! That can be a BIG savings. If you order from DB, but sure to check for specials - most of the time they have a code you can enter during the order process that will get you shipping for only $6.95 no matter the size of the order.

I tried adding some powdered xyrellic to a small batch of Scorpion, and it did exhibit a little bit of clumping. However, I was working with a small fluid 2oz batch, in a 4oz bottle. I was simply vigorously shaking it. It almost dissolved the clumps, but not 100%. When I mix more powder into solution, I guess I'll have to do it in a large enough batch to used the drill end mixer. Maybe 1/4 to 1/3 of a quart at a time. I'll play around with the ratios to see what works. If it is too concentrated with powder, I can always gradually add more clear to the mix until it seems about right.

In the back of my mind I always thought that if I had to mix small amounts of paint really well I would make a miniature version of the squirrel-cage mixer; but I haven't done so yet.

The xyrellic looks alot like the paintonscreen sample, once its added into gray latex paint. From the looks of it, I'd say its pretty likely that they are using xyrellic or something pretty similar.

I haven't seen that sample yet in the mail. Are you done with it yet? No hurry if you're not... just wondering. What did it look like under the microscope?

I thought I read something on their site that said they used aluminum, but I could be wrong about that.

My apologizes for taking so long to get that last sample back to you. I just got it ready to mail earlier tonight, it will go out tomorrow. I'm sending you a sample of my first screen; it was made using the old formula for SF after I tried to color correct it (this was before I knew what I was doing, but it is still more neutral than the official mix) and thought you might be curious. It's also a good sample to compare your test samples to for sheen - if they have as much, or more, sheen than that SF sample it's a good bet that mix would hot-spot.

I haven't fired up my QX3 USB microscope yet to look at the paintonscreen sample. I have been having internet problems and getting a WiFi router going... Will get to it soon and send you a report. :T

 

[DavidHawke]

I wouldn't doubt it if the S1 sample had some pearls as well as aluminum in it. The scorpion sample with Xyrellic added, looked closer to the S1 under sunlight than anything else I've seen to date. Of course the color was different, but the pattern and look of the reflectives seemed spot on.

Besides, the S1 sample boosted gain like only pearls can. I'm also 90% sure that the rep at paintonscreen mentioned the use of high grade pearls when I was picking his brain over the phone (when I called for the sample).

I'll pick up some LMM soon, and I look forward to checking out the SF sample you're sending.