Is cold blue safe on a brass mold?

[boatswainsmate]

Hello All,
I keep getting tin oxides stuck on the mold faces of my MP brass molds when running fast and hot. I've tried Kroil and smoking them with a butane lighter which seems to be a temporary fix. I saw in another post of someone using cold blue for a patina in their brass mold. Just wondering if this works. Thanks in advance. Boats

[gwpercle]

If you haven't bought any bluing yet , you might want to try Birchwood Casey Brass Black .
It's formulated to put a black finish on brass and will work better than a solution formulated to darken steel .. cold blue solutions . I'm sure the cold blue will not damage brass but the brass black may do a better job . I've never tried cold blue on brass .
Gary

[boatswainsmate]

If you haven't bought any bluing yet , you might want to try Birchwood Casey Brass Black .
It's formulated to put a black finish on brass and will work better than a solution formulated to darken steel .. cold blue solutions . I'm sure the cold blue will not damage brass but the brass black may do a better job . I've never tried cold blue on brass .
Gary

Thanks. Did you apply it to the cavities?

[Tripplebeards]

I baked my mold several times on the oven before using and it seemed to work out quite well. I noticed I still had just a hair of tinning towards the end of my 2 nd batch because I got the mold to hot. I was thinking of trying vinegar and salt fumes on my mold next. I did some patina on a reproduction brass buckled sling that turned out nice.i can tell you it showed more oxidation and patina in 20 minutes this way than baking my mold 8 times in a row.

[boatswainsmate]

I baked my mold several times on the oven before using and it seemed to work out quite well. I noticed I still had just a hair of tinning towards the end of my 2 nd batch because I got the mold to hot. I was thinking of trying vinegar and salt fumes on my mold next. I did some patina on a reproduction brass buckled sling that turned out nice.i can tell you it showed more oxidation and patina in 20 minutes this way than baking my mold 8 times in a row.

Thanks

[USSR]

I baked my mold several times on the oven before using...

That's my SOP.

Don

[boatswainsmate]

That's my SOP.

Don

Thanks

[Outpost75]

The wet soapy water patches which have become thoroughly blackened after cleaning my cowboy guns after shooting BP loads do a really nice job of blacking brass backstraps and grip frames on my Pietta revolvers and brass Yellow Boy rifle receivers so that they look just like blued steel. I see absolutely no reason why a dirty BP cleaning patch used with plain water and a wee bit of detergent wouldn't do a dandy job in blacking brass mold blocks. Clean blocks with hot water before casting and you should be good to go.

[boatswainsmate]

The wet soapy water patches which have become thoroughly blackened after cleaning my cowboy guns after shooting BP loads do a really nice job of blacking brass backstraps and grip frames on my Pietta revolvers and brass Yellow Boy rifle receivers so that they look just like blued steel. I see absolutely no reason why a dirty BP cleaning patch used with plain water and a wee bit of detergent wouldn't do a dandy job in blacking brass mold blocks. Clean blocks with hot water before casting and you should be good to go.

Thanks

[megasupermagnum]

The wet soapy water patches which have become thoroughly blackened after cleaning my cowboy guns after shooting BP loads do a really nice job of blacking brass backstraps and grip frames on my Pietta revolvers and brass Yellow Boy rifle receivers so that they look just like blued steel. I see absolutely no reason why a dirty BP cleaning patch used with plain water and a wee bit of detergent wouldn't do a dandy job in blacking brass mold blocks. Clean blocks with hot water before casting and you should be good to go.

That's too funny. On the shotgun I used for turkey this year, I was worried the brand new ramrod end was too shiny. I wiped it a few times with a spit patch I swabbed down the dirty bore. After a couple applications, the brass turned a nice dark brown.

[DHDeal]

I may have been one to mention using the bluing on a brass mold. Specifically I used Dicropan T4 from Brownells. I just did another MP Mold on Monday. It takes a little time to keep rubbing it in with strong qtips, but it eventually gets to an even brown color. After I wash them off, I'll run them through my oven for a while and then rub the inside flat surfaces with some burlap. The whole process may take an hour and a half counting a 30 minute bake and cool down.

Why? Well, I have 8 of these molds now and some are a PITA with the tinning. I can't always tell I have some of that stuff on the edges of the cavities until it's cooled down and I look at the mold under my big lighted magnifying glass. Guess what, the mold is now cold and that stuff is tough to remove even when the mold is hot. When the mold is cold, well you know...

Someone mentioned bluing or some such process in one of the many threads about tinning on a brass mold on this site. WTH, I thought I would give it a try. It has worked on the 4 molds I've done it to. I only do the flats and not the cavities.

Is it possible to still get tinning? Probably, but I watch them closely and keep a piece of burlap and stiff qtips and will wipe the faces occasionally when the mold is HOT. No tinning seen since, even under the magnifier. Worst case I figured would be my mold wouldn't be as pretty inside, but the bullets sure are. YMMV, but cleaning that gunk is truly a PITA and those molds want to be run hot and fast.

Your thread asks if it's safe to use bluing on a brass mold and I don't know if it will cause any problems down the road. I have cast at least 1000 bullets using 3 of the 4 molds I've done this process to. The molds are fine with no tinning stuck anywhere I can see under 7×, but they aren't a shiny brass color anymore on the faces. Small price for me to pay for a wonderfully casting mold. To add insult to injury, I've also retrofitted another M6 screw as a sprue plate stop on all of my MP Molds. The roll pin gets pulled out, the hole gets tapped M6 and a hole gets drilled and tapped for a set screw the exact same size as the other end. McMaster Carr is my friend.....

[boatswainsmate]

I may have been one to mention using the bluing on a brass mold. Specifically I used Dicropan T4 from Brownells. I just did another MP Mold on Monday. It takes a little time to keep rubbing it in with strong qtips, but it eventually gets to an even brown color. After I wash them off, I'll run them through my oven for a while and then rub the inside flat surfaces with some burlap. The whole process may take an hour and a half counting a 30 minute bake and cool down.

Why? Well, I have 8 of these molds now and some are a PITA with the tinning. I can't always tell I have some of that stuff on the edges of the cavities until it's cooled down and I look at the mold under my big lighted magnifying glass. Guess what, the mold is now cold and that stuff is tough to remove even when the mold is hot. When the mold is cold, well you know...

Someone mentioned bluing or some such process in one of the many threads about tinning on a brass mold on this site. WTH, I thought I would give it a try. It has worked on the 4 molds I've done it to. I only do the flats and not the cavities.

Is it possible to still get tinning? Probably, but I watch them closely and keep a piece of burlap and stiff qtips and will wipe the faces occasionally when the mold is HOT. No tinning seen since, even under the magnifier. Worst case I figured would be my mold wouldn't be as pretty inside, but the bullets sure are. YMMV, but cleaning that gunk is truly a PITA and those molds want to be run hot and fast.

Your thread asks if it's safe to use bluing on a brass mold and I don't know if it will cause any problems down the road. I have cast at least 1000 bullets using 3 of the 4 molds I've done this process to. The molds are fine with no tinning stuck anywhere I can see under 7×, but they aren't a shiny brass color anymore on the faces. Small price for me to pay for a wonderfully casting mold. To add insult to injury, I've also retrofitted another M6 screw as a sprue plate stop on all of my MP Molds. The roll pin gets pulled out, the hole gets tapped M6 and a hole gets drilled and tapped for a set screw the exact same size as the other end. McMaster Carr is my friend.....

Thanks for the info

[mazo kid]

I can't answer as to damaging the mold, but if you want to try blackening the brass, try this....If you already have cold blue, you don't need to buy BrassBlack. I have used B-C cold blue to blacken a brass grip frame and it worked instantly and well.

[Mk42gunner]

Outpost75 beat me to the answer. I found out about BP residue darkening shiny brass the very first time I cleaned my CVA Kentucky pistol back in 1977. I think it is the Sulphur residue that reacts with brass.

As a former plumber/ AC&R repairman, I can tell you that if you re getting tinning on brass molds, there is a clean spot right there. Solder (tinning) will not happen unless the brass or copper based metal is clean. Any kind of patina will inhibit tinning, the darker the better.

Robert

[gwpercle]

Thanks. Did you apply it to the cavities?

No . My wife works doing engraving on brass plates for trophies . Some like the brass plate to be black with the brass engraving to be brass so they show up better , that's the stuff she uses and it blackens the brass very well, almost like it was made for it .
I own no brass moulds and know nothing about them .
The aluminum & steel moulds I cast with work best with a natural patina that gets baked on with use and heat cycling ...usually 3 to 5 sessions will season the blocks.
To prevent stuff from sticking to blocks I have treated them with a spray of Liquid Wrench Dry Lubricant ( L512) . The spray is micro particles of Teflon in an alcohol base , spray an even coat on a cool mould and the alcohol evaporates leaving a thin film of micro Teflon ... like a Teflon coated frying pan ...nothing sticks to it . I have also sprayed the cavities and sprue plate top and bottom and the blocks . I find it most useful on the sprue plate around the sprue holes where lead wants to stick and on the underside of the plate and the block top . This stuff will not cause wrinkled boolits .
If you are having a problem with stuff sticking ... try it and see how it works .
Gary

[boatswainsmate]

Thanks for all the comments and advice

[Dragonheart]

I run two molds simultaneously. While one is filled the other is cooling. Production increased and the molds go much, much longer without a stop, as those pesky bits of alloy take a lot longer to form. Also try coloring your mold faces, top and cavities with a #2 pencil lead on a clean mold to start.