My 2nd Krag

[ssgross]

This stuff works pretty quick. I followed the instructions to the letter. Results are good, but not perfect - and it's all my fault. The product seems to work great. https://www.rustblue.com/shop/bluing...blue-american/
Here are some pics of my first attempt.
Attachment 118463Attachment 118464Attachment 118465Attachment 118466
pics are prepped part, parts after first rust, after first boil and carding, and after second rust + boil + carding. Final finish is actually darker than it looks in the camera lighting

The instructions call for a first application, parts at room temp, and let completely dry for 2 hours. Then, another coat, heat parts above 100F, then let rust.

The mottles showed up after that first prep coat, and became more defined in the first rusting.
After a second rusting, they went away but the edges of where they were don't. In short, I think the activation coat and first coat were were too heavy, and fumbling the parts around in my gloved hands didn't help as my fingers got wet with the solution.

After applying the solution, I heated the parts with a heat gun, put towel soaked with hot water in the bottom of my pot, and put the parts on top of a plastic lid. Sure enough, in an hour they were fine velvety red as in the pic.

I think the trick is to make sure the solution dries quickly before leaving in humid environment to rust. So, I lightly sanded just the buttplate to start over and try again, this time using my case dryer at 122F to dry the first "activator" coat, and heat the parts before the first main coat goes on.

Then again, looking over my original krag, which still has 75% or so of its original finish...there is some similar mottling on the loading gate and side plate. Maybe it has to do with the way they were case hardened?

[browningautorifle]

I think you're right about it needing to be an even coat without touching. I know there's a few here have done this, wish they'd drop in for a look.

[ssgross]

rcathey's post looks like he ran in to the same issue his first go at it. I'm awfully surprised there isn't more out there. 1 billion posts and articles about nuance tricks for cold bluing with a myriad of different products. I might have to do a lesson's learned recap how to when I'm all done.
I'll see how the butt plate turns out today before starting over on the other parts. I have one of those super nice soft carding wheels from brownells on the way since last week - the light mottles on my parts may just buff out with something a bit more aggressive than just steel wool. https://www.brownells.com/gunsmith-t...-prod6762.aspx

[browningautorifle]

I might have to do a lesson's learned recap how to when I'm all done.

I think so, I have a Marlin 1936 here that could use work.

[rcathey]

I found that I didn’t like the finish I got from the carding wheel.

I don’t know what it is…maybe I see some slight rounding or polishing from it. Anyway, I prefer the way the finish looks after carding by hand. Brownells sells a handheld brush for carding.

Even 3M stainless steel scrubbing pads work great.

[ssgross]

Giving it another go tonight.
The instructions say to let that initial coat dry for 2 hours.
In my first attempt, I think this was too long as things started to rust, then the real first coat went on and I waited an hour in my sweat pot till I had a nice velvet, but some spots had started to visibly etch the surface. Brownells classic solution has similar instructions, but call to warm the parts first, let initial coat sit for 1 our before the first real coat. I

The second time I tried over the weekend, I put the initial coat on parts on parts warmed by the hot water I rinsed them in, and after ringing out the swab super good and drying my gloved fingers before applying. I then put them in the case dryer at 115 for an hour to prevent the deep etching I got the first time around. I put the first real coat on and let them sit for an hour in my sweat pot wet towel in the bottom, heated to maintain 90F on my hot plate). Got a nice thin even velvet after an hour. I think my mistake with this second attempt that caused spotting was the temperature difference in the steamer pot was too high, and condensation happened before the rust converted, causing some spotting on the loading gate, buttplate, and the slightest ring on the sideplate.

The other thing the brownells instructions indicate is that slight spotting in subsequent coats will even out with each iteration, so maybe the 4 iterations I gave it wasn't enough. So, in this attempt today I am boiling the first coat instead of steam, and if I use steam later for barrel and receiver, I will heat the parts up above 150F before introducing to the steam pot. Fingers crossed, wish me luck.

[ssgross]

I think I did it! I was a bit sparing in coating some of the parts for fear of streaking and puddling, so after boiling I had a couple missed streaks and a corner, but these will fill in even with subsequent iterations! The key is certainly warm parts so the solution evaporates quickly, especially the initial and first coat.

[ssgross]

well. I spoke too soon. I got 3 iterations in tonight and, and learned a new lesson...after ringing out your swab, put it down! and DRY YOUR FINGERS before applying. I must have dripped some solution off my gloved fingers when putting the buttplate back in the sweat pot...as well as the trigger gaurd, after applying solution the third time. They came out with a dot of heavier rust on them 45 minutes later. carding the spot after boiling took off all black, and left a finely pitted spot. Everything else turned out perfect.

second lesson learned...don't go cheap on the nitril gloves...I have a half dozen boxes of 5 mil from harbor freight when I stocked up at the beginning of the pandemic. A piece of steel wool must have punctured the glove as I held the steel wool and drops of sweat kept leaking out! Rinsed immediately in alcohol, and no harm done. Fortunatel I also had a box of the heavier 7mil gloves. Soft carding brush from brownells ordered.
Everything, especially the tsideplate, got significantly several shades darker on the third boil. I'll keep doing them with each iteration of the buttplate trigger gaurd redo.

[ssgross]

Hopefully I won't jinx it. Got the action small parts done last Sat., loading gate, side plate, trigger and sear. Been working on the receiver, 1 or 2 iterations a night. If I can get 2 or 3 in today, there will be pictures.

The stupid buttplate...had to restart again for like the 5th time now. After the 3rd iteration it always seems to streak and mottle. Finally figured out the issue though I think. The metal is different! Why would buttplates be hardened? The metal is softer than all the case hardened parts, and the 320 grit is then too course. So last night I used 400 grit and it seems to be coming out much better. My sanding tips for rust blue prep....
0) Use paper backed by file or hardwood block as you work through your course grits. If you get deep scratches, finish that grit by backing with a rubber eraser and lightly "top dressing"
The grit of your final pass should be dictated by the type of metal. When you get to it...
1) Use paper backed by file first to remove deeper scratches from previous grit. backing with metal makes the grit "bite" more easily, and deeper.
2) use same grit, but backed by wood next. This smooths out any deep ridges from (1)
3) finish with same grit backed by a rubber eraser to even out to a uniform satin.

[ssgross]

I'm thinking about the setup for bluing the barrel. I could repurpose one of my 140000 BTU/hr propane burners and pot from my brewery to make a stable platform for a PVC steam tube, use a scrap piece of sacrificial plywood for the lid.
Or, I could buy a wallpaper steamer at $60 for the steam, and save the time disassembling the brewery (it's all hooked up to a control panel and automated).
Or, I could use a water heater element in the bottom of a heavy wall pvc drain pipe
https://gunstreamer.com/watch/electr...EYEMhmdE2.html

Note: If the video doesn't play, your ISP likely blocks gunstreamer.

I'm leaning towards the water heater element and boiling, unless my cheap hot plate will boil a couple inches of water vigorously enough to create enough steam.