Browning Problem - texture flaking off

[E.vonAschwege]

Hey folks,
   I don't usually use browning solution, and typically just leave the barrel (bore greased up) outside for a couple weeks in the rain to develop a nice natural patina - that's even easier in the Pacific Northwest now that rainy season has started.  On my last build I used LMF Browning solution on the barrel and really wanted to give it some texture, so I continued to apply 2 or 3 times a day in my damp bathroom, spritzing with water here and there, for about a week.  It developed a gnarly texture, just where I wanted it to be, so I neutralized with ammonia and rinsed with water.  Everything received a coat of oil afterwards.  Now however (about 10 days later), the brown color and texture is flaking off, leaving the pitted steel underneath.  I don't mind the pitted steel, it's what I was going for, but it does mean I have to refinish the brown color here and there.  What did I do wrong to cause the scale to fall off?  At one point after browning I heated the parts (not very much) to drive off any extra moisture before applying the oil - could the heat have loosened the scale?  Thanks for your thoughts,
-Eric

[PPatch]

Roger Sells is probably your man on this question Eric. He gets some fine texture on his barrels via browning and may have ran into the problem. He is a member here.

dave

[D. Taylor Sapergia]

Eric, I'd say, "too much too fast".  Spritzing with water may be the culprit.  I know that if in my damp box, I go above the dew point, and droplets form on the barrel, the job is ruined, and I must re-polish and start again, especially with LMF.  But then again, I am not looking for that abused 150 yr patina look. 

[rsells]

I have never used LMF browning solution, so I can't comment on what is causing it to scale.  I have used Homer Dangler's browning solution with good success.  I apply it twice a day for 7 to 9 days without carding the surface.  It is labor intensive, but I clean all the scale off the parts until they are bright leaving the pitted surface.  I either use the browning solution to get a light brown or 44-40 cold blue solution to turn it black.  The last step is to take steel wool and buff it back to the color I am looking for.  Shades of brown or shades of grey.  I think I would try to steel wool the flaked areas a bit and rebrown it in that area to see if I could get it to match.   Good luck with your work.
                                                                                        Roger

[rmatt]

I had the same thing happen to a barrel. I was browning two barrels at the same time. they were right next to each other during the process. one barrel was new and the one that flaked was new but had been finished with cold blue. The browning was done in my basement with a tub of water on the furnace and the barrels hung above with no spritzing. I carded both when there was rust. They both looked pretty much the same during the process. It was after that the previously finished barrel started to lose some of the finish in places. Not all of the barrel.
I thought I had not prepared the barrel well enough. I took the barrel back to bright, degreased it and tried again. This time it took pretty well but still not like the new barrel. So that's my experience but no solution as to why. The barrel that flaked was an older manufactured barrel that had sat around for awhile with the cold blue finish on it until I removed the finish and browned it. It was LMF that I was using. Never had issues with LMF before. 

[Dave Dolliver]

I have noticed in the past that if I applied the LMF too heavy I found a copper colored deposit forming on the barrel which interfered with the browning.  Sometimes a dark, almost black, coating would develop that also interfered with the brown.  My rule has become to apply as thin a coat of LMF as I can,  leave in the open an hour or so until a gray coating develops so that any places that have not been covered show up and can be coated.  Then into the humidity cabinet until a uniform coating of red rust develops. Card and repeat until the desired finish is developed.   Go slow and don't try to hurry.  It's been hard to bring a "holiday" left after a first coat up to where it won't show later.

Dave Dolliver

[WadePatton]

Somewhere on here when i was reading all i could about LMF browning solution, i gathered to dilute it with water.  I don't recall the exact purpose of such dilution, but that's how i started using it - 1:1.  Works fine that way in my limited experience.

[Long John]

Eric,

I have used LMF for a number of rifles and have never had your issue.  However, I do it differently than you.

First, I clean the barrel VERY WELL.  First hot soapy water, then lacquer thinner, then another bath with hot soapy water, all while wearing canvas gloves.  I don't believe the assertion that the LMF is a "degreaser".

Second, I wipe each flat with a single swipe of a cotton patch soaked in LMF so that the surface is merely dampened.  I do not allow droplets of solution to appear on the barrel flat.

Third, I put the barrel in a damp box I made that is equipped with a pair of incandescent light bulbs and a pan of water with a cotton rag in it as a wick.  I let the agent work for a full 12 hours.

Fourth, I card the surface with a piece of 100% wool blanket.

These steps are repeated every 12 hours for 4 to 5 days.  The first couple of cardings don't seem to have much in the way of rust formed on the surface.  Don't worry, be happy.  Subsequent cardings exhibit more rust but much of it seems to wipe off.  Don't worry, be happy.  By the end of the week you will have a matte textured barrel with a deep even brown.

I then wash the barrel thoroughly with hot soapy water, lot's of it! I have never used a neutralizing agent, just lot's of water to dilute and wash away any remaining browning agent.  I dry the barrel, using WD-40 as a final drying agent.  Then I use a propane torch to heat the barrel until bee's wax will melt on contact and I melt bee's wax over the entire barrel surface while heating.  Eventually the barrel is dripping with liquid wax all over.  I take a rag and wipe off the excess wax.

Barrel done.

That's how I do it.  If you like the look I get then feel free to use the same process.

Best Regards,

JMC

[bgf]

You might have polished it too much before rusting--180 or even 150 will leave more tooth and not show on the final surface if heavily rusted or matte/satin finish is the goal.  I've even done 120 on things for my own use and like it, then I did a 60 grit piece for an agricultural implement and liked it even more in that application.  I find that highly polished surfaces do not rust (brown or blue) very uniformly.  I know I'll get arrested by the quality police, but it doesn't make sense to polish like a mirror if you want a satin or matte finish, plus a thorough job with even 120 for example looks a lot nicer than one might think. 

Just something that occurred to me, as I don't think you said what extent you polished before browning.

[E.vonAschwege]

Thanks for your thoughts everyone.  The parts were finished to about 150 grit, some even had coarse file work still on them.  It's not consistently flaking off, just in areas where the texture built more heavily and wasn't intentionally toned down (for example, on the triggerguard, the exterior of the bow was smoothed down, while the post where it meets the front extension was left quite coarse and is now flaking).  I'm leaning towards the "too much too fast" explanation in those areas, and perhaps I worked things before the finish had time to really set?  As far as I'm concerned it's not going to hurt the look of the piece - I'll fair it in with the existing finish and re-brown to get the color I want.  I'd like to avoid it in the future though, or have the entire finish flake off (before I rivet parts to the stock  ).  In this case, random texture and strange happenings are acceptable - it's an attempt at an all-out fake as far as finish is concerned, complete with worn pieces, dents, dings, vise marks, and a few "what the heck was that??" marks as well.  Photos to be posted in a week or two.
-Eric 

[Roger B]

You were a little too liberal with the amount of chemical and water you used.  If you get runs or puddles in the finish it just won't dig in and brown.  What you want is "moist" and "even" when you apply the LMF or anything else.  I use moistened (not wet) swabs or Q tips to apply the acid to the barrel sparingly.  What you want to see is a moist sheen on the barrel, uniform from top to bottom.   There are just so many molecules on the surface of the barrel for the acid to grab, so more isn't better. Do gently card between coats with oil free steel wool or a light Scotchbrite sanding pad.  That simply makes sure that you are not "stacking" acid coats, and allows the acid to get to the barrel metal in thinner places. I just barely drag an edge over the finish and reapply.  More coats work better than prolonged exposure.  I use baking soda to neutralize with since ammonia smells so good.  There should be plenty of humidity in the air where you live to brown anything without extra water.  Different here in AZ and much of the intermountain west.  If you feel like you need extra humidity, pick up a cheap steam vaporizer and run it in the room you are using to brown.  Don't aim it at the barrel though.  The best barrel prep I've ever seen was done with small bead blasting by my cousin, "The Tulsa Stripper".
Roger B.

[flehto]

I've had excellent results w/ LMF. First off, I draw file and lightly rub w/ 220 grit, use mineral spirits to degrease , a final wash w/ Dawn and a hot water rinse.

A small LMF dampened cotton patch  is run along each bbl flat and then into the "sweat box" that has hot towels on the bottom which are reheated every 4 hrs and after 12 hrs, another damp application is made and the bbl is carded after 12 hrs. A nice etch or matte finish is achieved  and the next damp application and 4 hrs in the "box"  is repeated w/ a carding in between until the bbl is the right color. A heavy denim is used for carding.

My "sweat box" is a real cheap affair and found out that a plastic cover causes condensation  and the beads can land on the bbl....so now use a cardboard cover.

Never take any handling  precautions after the wash w/ Dawn or when carding.

This "system" works well in my very dry basement during the winter months when the browning is done.

For the smaller parts, a smaller "box" is used and sometimes the browning is too rapid and a heavy rust is present and then I use green Scotchbrite for carding......Fred  

[Dave B]

Eric, What has happened is you have built up too thick of a rust layer and Iron oxide is brittle. I have done exactly the same thing using LMF on one of my rifles. I let it go too long between carding and it got knarley. I had sections flaking off. It must be from too heavy a coating. The top surface layer being harder separates from the underlying metal when under stress or impact. I was really surprised with it came off in patches were I had bumped it with something hard. Since then I have kept up the carding every couple of hours, keeping the grain fine for a consistant finish. The NW damp will let things get out of hand in a hurry if you don't keep after it.

[smart dog]

Hi Eric,
I browned a number of barrels in humidity conditions similar to what you experience in the PNW while I lived in Ketchikan, AK.  I think your browning simply went too fast.  I actually had to slow down the process by using a dry box with a light bulb or I ended up with too much texture and flaking.  Under your humid conditions, you may also experience some rusting even after you washed the barrel and applied oil.  Good luck.

dave

[E.vonAschwege]

I agree that the browning went too fast - I didn't realize that could happen.  It's happening on a few other small projects I browned as well, which I didn't even try to brown as aggressively.  Indeed a few weeks later and some of the rust on other projects is scratching off (leaving an awesome surface beneath it!). 
-Eric

[Dphariss]

I think Taylor nailed it with the too much too soon thing.
But like he stated I do not do this either and don't try for a "textured" brown.

Dan

[flehto]

I'm presently browning a Rice bbl using the same method as I've done  on a couple of dozen bbls previously and this bbl , especially the tang is , isn't browning evenly as w/ past bbls. The tang has little circles of bare metal that won't brown....have taken it down to bare metal but the circles still persist, There were a few of these circles on the bbl also. My method is very slow but has always yielded an etched, matte finish which is very smooth after the 0000 steel wool is used. Seems like something in the metal isn't completely alloyed. Most of the previous bbls were from Rice.....Fred

[Vomitus]

   Question.  Wouldn't the metal be more receptive to the "brown" if it were sanded down with a courser grit emory, say 320 grit? Thx.

[E.vonAschwege]

I always figured that a coarser texture would give the acid and subsequent rust a bit more to bite onto - the smoother it is the less likely it is to rust - I polish my breech plug faces almost like a mirror and nothing sticks to them. 

Fred - Have you tried wiping the barrel down with lacquer thinner or alcohol?  Could be some kind of oils or silicone preventing the browning. 
-Eric

[flehto]

I degrease w/ mineral spirits, then alcohol and a final wash w/ Dawn. All the previous bbls were done as described and came out fine. This is the first bbl of over 2 dozen that's giving me trouble. Just went down to bare metal again w/ the unbrowned spots...we'll see what happens. As I said....my procedure is very slow which yields a really nice color and matte finish. Hopefully won't have to go to bare metal and  start over....browning  has been the easies and most trouble free part of building LRs....don't know what happened this time.....Fred