Help!

OK, I'm definitely not a painter. I bought a gallon of the dark green zinc chromate for my spar components and when I opened the can to split it into four new quart cans I found an inch of chromate(?) cake in the bottom that was too stubborn to mix. I took it to Lowe's and had them shake the **** out of it, but it improved little. I poured 90% into the quart cans and tried cutting the cake with progressively hotter solvents, ultimately MEK. Improved, but no joy.
Is this just bad primer?

tried breaking it up first?

You don't say how old the material is, but my suggestion would be to use mixing sticks or something else to get all the hard stuff loose from the bottom and broken into bite size chunks. Then try the shakey machine...

The shakey machine usually won't break up a settled layer at the bottom if it's had the chance to really settle in there...

good luck!

Bill,
I use Sterling U-1201/U-1202 Mil Spec epoxy primer. Like your Zinc chromate primer, the solids will always settle to the bottom. The longer the can has been sitting, the harder it is to mix it back up.
I've found that the best way for me to mix my primer is to use an "egg beater" type mixer (found in the paint department of Lowes or Home Depot) with a 1/2" heavy duty drill motor. I jam the mixer right down into the "gook" to speed the process up.
Charlie Kuss

I recommend buying a paint shaker for yourself. About $100 from Harbor Freight. I used mine a lot during my project (especially since I painted it myself). Paint that has been sitting on the shelf for a long time can take a while to break up and mix really well. With your own shaker, you can just let it shake for 45min to an hour and it'll be good. If you get one, you'll need a decent compressor to keep up with the air requirements.

Good luck.

Bob Brown said:

You don't say how old the material is, but my suggestion would be to use mixing sticks or something else to get all the hard stuff loose from the bottom and broken into bite size chunks. Then try the shakey machine...

The shakey machine usually won't break up a settled layer at the bottom if it's had the chance to really settle in there...

good luck!

Click to expand...

The can showed an expiration date of May 08, but I didn't see a manufacture date. I worked at the cake for quite a while with stir sticks and a drill mixer and lot's of thinner. Looks like the chromate took a set. I'll update after Tex Air Parts helps figure this out. I alodized all the parts (using a plastic-lining in the shipping crate for a dunk tank) before I primed, so I'm not overly worried about not having maximum chromate concentration (I think). I definitely WILL be buying a paint shaker. Fortunately, a birthday is coming up, anyway!

Harbor Freight?

JordanGrant said:

I recommend buying a paint shaker for yourself. About $100 from Harbor Freight. I used mine a lot during my project (especially since I painted it myself). Paint that has been sitting on the shelf for a long time can take a while to break up and mix really well. With your own shaker, you can just let it shake for 45min to an hour and it'll be good. If you get one, you'll need a decent compressor to keep up with the air requirements.

Good luck.

Click to expand...

Jordon,
Good suggestion, but I can't find any at HF. Can you send me a link?

JordanGrant said:

I recommend buying a paint shaker for yourself. About $100 from Harbor Freight. I used mine a lot during my project (especially since I painted it myself). Paint that has been sitting on the shelf for a long time can take a while to break up and mix really well. With your own shaker, you can just let it shake for 45min to an hour and it'll be good. If you get one, you'll need a decent compressor to keep up with the air requirements.

Good luck.

Click to expand...

Jordan,
Took your advice and got the HF shaker. My unit cost $139 and I love it! I plane to weld up a pipe/plate stand and anchor it to the floor, but I tested it by C-clamping it to my table saw and it definitely shook things up! I was able to mix that chromate cake after almost 5 minutes of aggitation (the can, not me). Brilliant call. But then I would expect that from a Grant.