Metal blackening

[Janger]

Jax black again...
After Kyle's suggestion of heating parts to clean them I cooked some test mild steel in my pizza powder coating oven. Then I dipped the parts in Jax Black instead of brushing while they were still pretty hot. It's better. The double dip is best but it's still not basic commercial quality. Maybe I'll try Peter's suggestion of multiple dips too.

More attempts. Try 3 and 4.

 

[Janger]

Dan Gelbart... he's actually a little Canadian dude I thought it sounded like maybe a Swiss accent, but he is originally from Israel. Oh, and a self made billionaire. One of those brilliant under-achiever types. Great video series. He has a retirement shop like Batman's cave.
http://makezine.com/2015/03/20/18-lessons-smart-prototyping-self-made-billionaire/

Wow look at that gear. What $500k maybe. Best of the best.

 

[PeterT]

Janger that looks about the same as mine come out. One experiment you might want to try is a real nice surface finish on same material, say 600 grit wet-o-dry. Remove all traces of abrasive & cutting fluid yada-yada & dip relatively soon after. The matt finish tends to look more even & that's entirely related to underlying metal surface finish. I also handle with those disposable gloves so as not to transfer finger grease & keeps the blackening stuff off the skin. I will check but I think that Jax brand is what I have from Kens & it seems to be the same as KBC.

 

[PeterT]

I was watching some How Its Made show on commercial parts, like socket screws maybe. After cleaning they dumped batches of the steel parts into a 'hot oil solution' & it seemed to me they were in there for a while. Even if the parts were preheated going into the bath, they very quickly would stabilize down to whatever the bath temp was. I think with all these cold wipe-on liquids we are discussing, you kind of get what you get. Its black alright, but its just not like the industrial stuff. This document & others like it pretty much say the same thing.

http://www.premierfinishinginc.com/wp-content/themes/filtered/images/Black_Oxide.pdf

The “cold” black oxide process, applied at room temperature or slightly elevated temperatures, are not true oxides, but soft deposits that offer less corrosion and abrasion resistance than the “hot” oxide process. The cold black oxides oftentimes display color variations on the same part or part-to-part. The “cold” process does not meet automotive or military specifications for black oxide coatings. Premier Finishing only employs the “hot” black oxide process.​

 

[kylemp]

I don't know if we'll ever see hobbyist or small run products that compare to the true industrial black oxide unfortunately. I've got a friend who may know something about it though, I'll ask him.
In the video of the tig welded parts the degrease in a hot solution and then clean in hot water, I think they also mention that the bead blasting really help and they talk about using a brush on it while submerged, maybe those 3 things would help? I'm heavily speculating as the shop I worked at just painted parts to look like black oxide..

 

[Janger]

Try 3 & 4

 

[kylemp]

Try 3 & 4

Seems like your getting closer..

 

[Janger]

According to that little German dude on YouTube if you can heat your parts to something like 350f it takes all the moisture and then burns off any hydrocarbons.. If you haven't watched his videos I'd suggest it.. But the one about painting covers it.
That may be helpful when doing this, his reasons for doing it is the single atom layer of hydrocarbons that is left and fucks up painting, may apply in this instance as well.

Here's the first one

Great series! Worth watching. I've seen several now. and of course now I need some new tools! :>

 

[Janger]

Try 3 & 4

So - some results - sanded the parts with really coarse sand paper on the angle grinder - took off a layer of mill scale and steel. Cooked it at max toaster oven temperature for 20-30 min and while still pretty warm immersed in the Jax Black. I brushed it under the bath, dried it off and repeated the dip and brush. Finally wiped it off and burnished some with steel wool. Too much burnishing and the black does come off. That's piece stamped number 4. I also did some fine sanding on one side to maximize surface smoothness. PeterT this does help. I think these results I can probably live with. Still I need to try it on a bigger "real" part and see...

I tested one piece with distilled water spray and it did wet out like Dan Gelbert suggests. He suggests for painting prep Sandblasting, oven cooking/cleaning, and washing scrubbing with a comet and or ajax type abrasive cleaner. Forget solvents of any kind.

 

[CalgaryPT]

Dan Gelbart... he's actually a little Canadian dude I thought it sounded like maybe a Swiss accent, but he is originally from Israel. Oh, and a self made billionaire. One of those brilliant under-achiever types. Great video series. He has a retirement shop like Batman's cave.
http://makezine.com/2015/03/20/18-lessons-smart-prototyping-self-made-billionaire/

I just checked out his YouTube Channel. Wow. I am so not worthy. If I am ever stuck on a remote planet and need to build a spaceship to get home, I want him (and his Bat tools) on my team.