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geargnasher
06-27-2012, 08:34 PM
I finally got it all together and did one. The discussion started in this thread: http://castboolits.gunloads.com/showthread.php?t=155919&highlight=anodize

For those of you who were interested, here's a pic of the results. It came out a bit dark but is quite nice. The oxide layer didn't amount to much, it looks like this mould will be about a half-thousandth smaller by the parting line and about the same perpendicular to it. I did dress the alignment "Vee" notches and the faces slightly beforehand in anticipation of the added thickness "Beagling" the mould slightly, which it did.

http://castboolits.gunloads.com/imagehosting/thum_89094feba647d7c48.jpg (http://castboolits.gunloads.com/vbimghost.php?do=displayimg&imgid=5688)

When I get it put back together and get a chance to cast with it I'll give a full report.

Gear

Thompsoncustom
06-27-2012, 08:45 PM
That's really neat, Ive anodized stuff before but a bullet mold never even crossed my mind.

btroj
06-27-2012, 08:46 PM
It sure is pretty

snuffy
06-27-2012, 08:47 PM
Cherry color huh? You'll have to call the boolits "cherry bombs")!:kidding:

Looking forward to the results.

MikeS
06-27-2012, 09:55 PM
I'm real curious how this makes the mould cast. Also would it help make the moulds last longer? If it helps the way the mould casts, and/or helps it last longer, I wonder if it would be something some of our custom mould makers (NOE, Accurate, etc.) could look into, as I would imagine if a mould is anodized during production it would be much easier to do, as it could be done before alignment pins are put in place, etc.

Mal Paso
06-27-2012, 10:07 PM
Finally! Color Coordinated Casting! :bigsmyl2:

TheBigBang
06-27-2012, 10:53 PM
I wonder about durability, especially under the sprue plate...

GP100man
06-27-2012, 11:20 PM
I want blue 1s !!!!

Kool job & look forward to a castin report !!

I thought the same thing a snuffy , cherry color, Hhmm Cherry Bombs !!

geargnasher
06-27-2012, 11:31 PM
It was supposed to be bright Lee red, but that's the way it turned out.

The point here is just to see if boolits fall out easier and if the coating on the block faces keeps lead bits from sticking to them. A properly "leemented" mould without any ridiculously deep lube grooves or narrow draft angles usually casts fine if the user does their part, but I wanted to see if the anodizing really helped prevent lead stickage. I'm not too concerned with the top part, I figure the coating will wear off eventually, but it might also hold sprue plate lube like a Parkerized steel finish will hold oil. If it does hold oil, that would be a huge bonus.

I polished the sprue plate too, so hopefully that will minimize wear on the finish.

Gear

SciFiJim
06-28-2012, 01:38 AM
Very interesting. I am in to watch on this thread.

And there are people that say that casting is old fashion and there is nothing new to learn.:)

geargnasher
06-28-2012, 02:49 AM
I got it all back together a few minutes ago, it looks like the coating hasn't affected the alignment much at all. Bullplate soaks into this finish very nicely, so I went ahead and treated all the critical points cold. Hopefully I'll have time to cast some with it in the next few days and give you folks a report on how it does. I can tell one thing already, the coating is much harder than the aluminum itself, so it IS sort of an armor plate for the delicate alignment points. This might end up being the most expensive Lee two-cavity mould in history.

Gear

BulletFactory
06-28-2012, 08:57 AM
You should have patented this first.

theperfessor
06-28-2012, 09:18 AM
Really interested in this thread, and such a pretty color. Good job so far, Gear.

popper
06-28-2012, 09:34 AM
If it works good you just found a second job. Does she do packing and shipping?

dpaultx
06-28-2012, 11:16 AM
Did the steel alignment pins reinstall without difficulty? Were they still tight in the slots?

Just curious . . . Doug

Chicken Thief
06-28-2012, 12:15 PM
Unfortunatly the colour will fade with temp.
The pigment degrades.

geargnasher
06-28-2012, 12:19 PM
Did the steel alignment pins reinstall without difficulty? Were they still tight in the slots?

Just curious . . . Doug

Went right together with some gentle persuasion (plastic mallet + cupped steel punch). Slightly tighter than when new, very good fit. You have to be careful not to let them get crooked and stretch the small supporting area. I started the pins in and once the tips were through the hole and would engage the opposite block, I clamped the mould together in a vise with hardwood blocks and drove the pins in the rest of the way and peened the hole.

Gear

L1A1Rocker
06-28-2012, 12:26 PM
I'll be darn. Looks great Gear. I'm also curious about how the alignment pins came out.

Doc Highwall
06-28-2012, 04:59 PM
Anodize is about 80 Rockwell. But it is also only about .001" thick before you break through it.

paul h
06-28-2012, 05:15 PM
Unfortunatly the colour will fade with temp.
The pigment degrades.

True enough, but it's the hard oxide outer layer that does the work, the coloring is purely cosmetic.

SciFiJim
06-28-2012, 05:23 PM
Unfortunatly the colour will fade with temp.
The pigment degrades.


So, is it eventually going to be pink? :holysheep

Elkins45
06-28-2012, 05:44 PM
So is anodizing something that you did in your garage with minimal components, or is it something you did at your job involving tons of expensive equipment?

MtGun44
06-28-2012, 08:26 PM
Did you boil it in distilled water for 15 minutes? If not, you need to do this to harden
the anodizing before you use it.

Bill

geargnasher
06-28-2012, 08:42 PM
That's affirmed, Bill.

As to all the "how to", Google has all the answers. Anodizing is a fairly simple process, but requires some really potent chemicals and some other fun stuff, so I'm not going to get into it here.

Gear

Quigley284
06-28-2012, 09:15 PM
Nice one Gear, looking forward to casting report. Mike

Catshooter
06-28-2012, 09:20 PM
Very interesting. I'll watch this one fer sure.

I electroless nickel plated a couple of Lyman moulds once. But I failed to get the moulds as clean as I did with other stuff I nickeled and contaiminated the solution. One mould did come out ok and it works very well. The nickel was about three eigths of a thousanth so no dimensional concerns at all. It darkened with use but never seperated or peeled.

I would think that your anodizing should work well. Good luck!


Cat

Jailer
06-28-2012, 09:37 PM
In for the results

MtGun44
06-28-2012, 10:27 PM
I wouldn't trust Google if they told me that the sky was blue.

Bill

olafhardt
06-29-2012, 03:34 AM
I don't have a thing to say, I am posting so I don`t miss anything. Gear for president!!!!

swheeler
06-29-2012, 10:53 AM
I have a couple anodized molds, believe it was Rapine that made TC molds.

williamwaco
06-29-2012, 09:46 PM
Hurry! Hurry!

I am MAD with curiosity.


.

NoZombies
06-30-2012, 12:54 AM
I have a very early Ideal all-in-one tool that still has the nickle in the mold cavity. I haven't tried casting with it (too busy) but I'm looking forward to seeing how that works out as well.

I look forward to seeing the results of the anodization. I think I've still got all the equipment and chemicals around someplace, but I'm not sure I'd want to go to the effort unless you get amazing results.

thehouseproduct
06-30-2012, 02:10 AM
In for results as well

nanuk
06-30-2012, 03:04 AM
I bought a "Shiloh" mould that I think is Anodized black....

haven't used it yet, but my understanding of anodizing is that it is more nonstick than nothing... but how much? I dunno.

Looking forward to Gear's results

Longwood
06-30-2012, 03:10 AM
I wouldn't trust Google if they told me that the sky was blue.

Bill

It is pretty simple Bill.
I have to feed some pets at my mad scientist friends house this weekend.
He has a test set-up in his garage right now,
I will try to remember to take my good camera.

Bullet Caster
06-30-2012, 03:32 AM
Gear, that mould looks awesome. I too, am keenly interested in the results of casting with an anodized mould. I am hoping this helps to release boolits with little or no effort and if it works, I'd pay extra to have my moulds anodized. BC

geargnasher
06-30-2012, 04:12 AM
First off, the dye did fade pretty badly, it's kind of a puke mauve color, but it works great! I ran about 300 casts through it tonight, treated the sprue plate, top of blocks, and alignment points lightly twice with Bullplate to get them seasoned, and there was absolutely ZERO visible wear on the finish. No sticking, no buildup, no problems. This mould has always tended to fin every so slightly on the corner of the meplat of one cavity and sometimes this sticks to the block faces. It did tonight a few times, but the tiny sliver of lead pushed right off with a dry Q-tip!

If I waited the right count after cutting the sprue, the boolits just fell out. I had to give a few of them a very light tap if I didn't get the timing right, typical of any mould. This is a definite improvement over the way this mould cast before, although it wasn't terrible. It drops the boolits out much easier now. I'm not going to say this coating is a magic mould release, it isn't but it absolutely prevents hard sticking of both boolits, lead smears, and flashing. toward the end of the session I deliberately tried to get boolits to stick and never could get them to stick worse than a light shake or a single tap (very light) on the hinge bolt would take care of.

As for size, the boolits actually cast exactly the same size as they did before the coating, but keep in mind I did a little work to make the blocks close more tightly before the coating, and the coating put them right back where they were. Boolits are still round, and still .4585" with this same alloy (50/50 WW/pure).

Another thing that just flat amazed me was how perfect the bases of the boolits were: Razor sharp and consistent. I think the coating helps the lead flow the same way every time, not letting the "wet" metal fin or round back from the edges. The driving bands were also razor-sharp, and I think the coating actually helps the mould hold heat better within the blocks, because I was able to cast much more slowly (about two pours a minute) than normal for the exact same results as before the coating, which usually ran about three pours per minute. Interesting stuff.

It's late and I'm too tired to mess with pics, but it is everything I'd hoped it would be and more. I think the mould manufacturers should look into this, and also possibly look into nickel-plating brass moulds. I've been trying to figure out how to make a practical go of a service doing this to production moulds for members here if they're interested, but the issues associated with removing and reinstalling some of the alignment pins and the dimensional hickies that might arise make that a tough proposition for moulds not specifically machined for the coating, i.e. oversized cavities and the cavities machined with a .001-2" shim between the blocks. I think the .001" thick layer would make a pretty big difference to a .30-caliber boolit, even though it didn't seem to make any difference at all in my .45 caliber one.

Hope this satisfies everyone's fancy, it sure did mine, and I plan to do this to more moulds in the future.

Gear

Jailer
06-30-2012, 09:07 AM
An expensive but viable option would be a mold from Accurate molds. Contact Tom and tell him what you are doing and he could cut a mold to your dimensions to accommodate the coating. You'd probably have to have him ship the bare blocks and install the alignment pins after anodizing as you'd have to have the alignment pin holes slightly oversize to start with as well.

I know it kind of defeats the purpose of improving a cheap mold to make it cast better, but it would be interesting to see if you could improve an excellent product and make it even better.

Doc Highwall
06-30-2012, 09:46 AM
Anodize does not actually build up. It is like reverse plating and the I.D. will actually get larger, I am talking like in .0001" of a inch. Anodize is not very deep, only about the same as bluing on a gun. Anodize is a protective treatment for aluminum to keep it from corroding and the surface is non conductive to electricity with the added benefit of hardness. Think of it as a pre rust to aluminum like bluing is to steel.

Doc Highwall
06-30-2012, 09:51 AM
I wonder if the anodize causes the molten lead alloy to bead up like when you put water in a nonstick Teflon coated pan allowing it to fill out and release better?

popper
06-30-2012, 10:22 AM
Al can be nickel plated also. We used nickel plated Cu wire, the heat transfer when soldering was nasty. Solder one end and couldn't hold on to the other end of a 20' length of #6 wire. Long time ago but I think the temp was ~500-600F. Don't know what effect that would have on casting. Hard anodize reduces conductivity, alodine increases it, I think. Goes along with your wetting theory.

geargnasher
06-30-2012, 05:47 PM
Anodize does not actually build up. It is like reverse plating and the I.D. will actually get larger, I am talking like in .0001" of a inch. Anodize is not very deep, only about the same as bluing on a gun. Anodize is a protective treatment for aluminum to keep it from corroding and the surface is non conductive to electricity with the added benefit of hardness. Think of it as a pre rust to aluminum like bluing is to steel.

How thick the coating is depends on how long you leave it in the bath and how much amperage the system is using, and lots of other things like cathode area vs. part area and concentration of the acid solution. To get 6061 to stop conducting electricity (usually the "done" point) the surface will actually increase thickness by about a thousandth. The surface oxidizes and turns into the coating, but the oxide is much less dense than the base metal so the coating actually adds to the thickness.

Gear

geargnasher
06-30-2012, 05:51 PM
An expensive but viable option would be a mold from Accurate molds. Contact Tom and tell him what you are doing and he could cut a mold to your dimensions to accommodate the coating. You'd probably have to have him ship the bare blocks and install the alignment pins after anodizing as you'd have to have the alignment pin holes slightly oversize to start with as well.

I know it kind of defeats the purpose of improving a cheap mold to make it cast better, but it would be interesting to see if you could improve an excellent product and make it even better.

That would be a good plan. I have a multitude of Tom's excellent moulds, but I never found even his aluminum ones to need much of anything, not really even sprue plate lube. I only use Bullplate on them for storage to prevent rust on the steel parts. Most of the time I order his brass moulds because I much prefer the heat-transfer properties of brass and the way it casts. I mentioned the nickle plating because if you happen to overheat the alloy or run a high-tin mix with a hot mould, the cavities can get a tin wash to them that is difficult to remove, and doesn't help the release much. I'm also careful when I design boolits to have him make, that I have plenty of draft angle on everything so the boolits aren't inherently "sticky" in the blocks by design.

Gear

Cap'n Morgan
07-01-2012, 01:22 PM
...and I think the coating actually helps the mould hold heat better within the blocks, because I was able to cast much more slowly (about two pours a minute) than normal for the exact same results as before the coating, which usually ran about three pours per minute. Interesting stuff.

Actually, anodizing improves aluminum's ability to radiate heat considerably. The emissivity coefficient of bare aluminum is 0.04 to 0.06, while an anodized aluminum surface has a coefficient of 0.83 to 0.86. But it could very well be that the coating layer reduce the heat conductivity between the molten lead and the mold. If so, we would have the best of two worlds... Looks as if you're onto something here, Gear.

http://qats.com/cms/2010/11/09/how-heat-sink-anondization-improves-thermal-performance-part-1-of-2/

popper
07-01-2012, 01:39 PM
Thermal conductivity - 6061 167, anodized .7 W/m-K. Data from Navel labs and NASA. Definitely a thermal insulator. http://www.dtic.mil/cgi-bin/GetTRDoc?Location=U2&doc=GetTRDoc.pdf&AD=ADA191755 . Nickle is 90, brass is about the same.

geargnasher
07-01-2012, 03:38 PM
Cap'n and Popper, that's why I think it helps the blocks hold temp better, while not overheating the boolits. The coating is like a thermal blanket around the blocks, and once heat actually gets inside, it tends to stay there. The blocks aren't radiating heat out to the air to quickly. The insulating effect of the coating in the cavities seemed to have no ill effects as far as fillout went, in fact quite the opposite. In any event, I'm impressed with how it worked.

Gear

SciFiJim
07-01-2012, 04:48 PM
So, if the anodized blocks aren't radiating heat to the air as quickly as non-anodized, it would work better for smaller caliber molds that have trouble with too rapid cooling. But wouldn't this then increase the issues of larger caliber molds getting so hot that they have to be cooled briefly between casts?

If so, what would be the break even point? Perhaps the benefit of non-stickiness is worth overcoming the heat problem for.

geargnasher
07-01-2012, 06:50 PM
The mould I did was the 2-cavity 457-340, that's a LOT of lead going in there. Even then it still used to like about three pours a minute with 700-degree 50/50 alloy or 675-degree WW. That changed to two pours per minute after the coating, so I'd say that it definitely holds heat better, BUT I don't think it would be a real disadvantage, because it's near top of the weight limit (cavity volume) for the block size and still didn't do what I would call "overheat". I wasn't having to fight it to keep it cool, just downshifted a gear and eased off the throttle. The sprue plate still lost heat at about the same rate, so that helps with sprue cuts and base quality. The 2-banger Lee moulds usually freeze the boolits before the sprue puddle by a wide margin when things are nice and hot, the coating balances that out better.

I think anodizing a smaller mould would help the heat thing quite a bit, especially with something like a Lee six-banger Bator mould.

Gear

williamwaco
07-01-2012, 11:08 PM
I've been trying to figure out how to make a practical go of a service doing this to production moulds for members here if they're interested,


Gear


If it proves to be practical, I would certainly be interested.

.

popper
07-02-2012, 09:34 AM
I think the insulating value would be preventing alloy from cooling too much while pouring those long or big boolits, give better fill and fewer wrinkles, i.e. run the blocks and alloy cooler to begin with. Downside to a value-added service would be the blocks have to be 'right' and can't be mod'ed afterwards. Durability would definitely increase, don't know about cleaning, anodize is more porous than Al, harder to get oil out? Talk to RD or Tom yet? After reading the posted article I was wondering if the other anodizing fluids might not react with steel or SS - would simplify the process for us.

SlippShodd
07-05-2012, 02:05 AM
Just lurking and listening...

geargnasher
07-05-2012, 02:14 AM
It's a done deal, it works. The only drawbacks are dimensional hickies it can create with moulds not specifically made to tolerate the oxide thickness, and getting the steel hardware like alignment pins out of the blocks and back in without ruining anything, although that was simple enough on my Lee two-banger mould. For these reasons I doubt I'm going to try to offer this as a service, and I doubt anybody would be willing to pay me what it's worth to strip, prep, and anodize a $20 mould for them, plus the shipping both ways.

Gear

MikeS
07-05-2012, 03:06 AM
Maybe not on a $20.00 mould, but what about a $100.00 or so mould? I have a mould that could really benefit from anodizing, a 5 cavity NOE 30 cal 129gr boolit. I can't seem to get that mould to cast worth a darn. I sent it back to Al, he checked it out, smoothed out the cavities some by spinning some boolits in them, but I still have trouble. I bet if it was anodized, it would act like a totally different mould!

Also, if you can get the anodizing process down good, perhaps you could offer the service, but only on moulds where the owner has removed the alignment pins, sprue plate, etc. so that all you're doing is the actual anodizing. It would be really cool if NOE offered anodized moulds as an option, although I'd much rather see them start making more brass moulds, but anodizing their aluminum moulds would be a step in the right direction. (at least as I see it)

Doc Highwall
07-05-2012, 11:29 AM
You could mask off areas that you don't want anodized with lacquer and even anodize just the cavities.
There is a lot you can do but how much effort are you willing to go through and what will be the cost and reward for it.

Sometimes we put a lot of effort into a project and the greatest reward is the satisfaction is that we did it.

popper
07-05-2012, 12:14 PM
MikeS - lots of commercial shops that do that now, and they do masking also. Unfortunately, they don't do many inexpensive 'one-offs'. You might get one to do an adder to their normal run.

Elkins45
07-05-2012, 12:32 PM
Maybe not on a $20.00 mould, but what about a $100.00 or so mould? I have a mould that could really benefit from anodizing, a 5 cavity NOE 30 cal 129gr boolit. I can't seem to get that mould to cast worth a darn. I sent it back to Al, he checked it out, smoothed out the cavities some by spinning some boolits in them, but I still have trouble. I bet if it was anodized, it would act like a totally different mould!

I have a similar issue with a NOE 5 cavity 311407 that only casts a decent bullet if ran at darned near thermonuclear temps. I can only cast from my bottom pour pot during the summer months, and only then if I hold it at 10. Anodizing might be just the ticket for it.

geargnasher
07-05-2012, 03:51 PM
Anodizing will not fix lack of draft. I don't think the NOE version of the Loverin boolits have enough draft angle on the grease grooves for easy release of the boolits. I can't say about the 129-grain boolit.

I appreciate the input on the masking, I figured anything that would keep the acid off the steel would protect it, but I have no idea what to use or how it would work.

Gear

Elkins45
07-05-2012, 10:13 PM
Anodizing will not fix lack of draft. I don't think the NOE version of the Loverin boolits have enough draft angle on the grease grooves for easy release of the boolits.

Release isn't the problem---they release just fine. Fill out is the problem, even with pure lino. It was the heat retention properties that caught my interest. I would love to be able to use this mold sometime other than the dead of summer with my pot at 10 in a 100 degree garage.

John Boy
07-05-2012, 10:53 PM
Over on Shiloh Rifle forum about a 2 years ago, Dan Theodore reworked a mold by boiling in soapy water, heat the mold, blue the cavity, then remove bluing ... do 2-4 times. Then blue the cavity only leaving the vent line halves with no bluing. Pictures of the resulting bullets were much more 'shiny' without the normal minor dimples in the metal. He also said they was a higher rate of bullets that dropped by gravity

The complete details are in the ASSRA Single Shot Rifle Journal, Nov/Dec 2010 issue

geargnasher
07-05-2012, 11:29 PM
Release isn't the problem---they release just fine. Fill out is the problem, even with pure lino. It was the heat retention properties that caught my interest. I would love to be able to use this mold sometime other than the dead of summer with my pot at 10 in a 100 degree garage.

Ahh. Sounds like you just need to cast faster, or like you said anodize them to help hold the heat. I have several six-cavity aluminum .30 caliber moulds and the all cast just fine with 675-degree wheel weight alloy once I get them properly preheated in my mould oven and then run them at about three pours a minute. I've run them in a chilly shop this way with no issues. You have to hustle to keep those blocks warm for sure.


Over on Shiloh Rifle forum about a 2 years ago, Dan Theodore reworked a mold by boiling in soapy water, heat the mold, blue the cavity, then remove bluing ... do 2-4 times. Then blue the cavity only leaving the vent line halves with no bluing. Pictures of the resulting bullets were much more 'shiny' without the normal minor dimples in the metal. He also said they was a higher rate of bullets that dropped by gravity

The complete details are in the ASSRA Single Shot Rifle Journal, Nov/Dec 2010 issue

Interesting. I've polished up some of my Lyman and RCBS moulds that had some rough machining marks using first a lap and very fine lapping compound, then a bronze bore brush packed with 6-ought steel wool and Turtle Wax Chrome Polish. They certainly do drop better after that.

Gear

popper
07-06-2012, 09:19 AM
Gear - there are lots of etch resists available for PCB makers and lithographers. Solder mask stuff may also work but getting it off is something else. Same with NASA PCB coating materials. Have to manually scrape some of that stuff off. Check with some of the anodize shops, they will probably tell you what they use for masking.

JIMinPHX
07-07-2012, 12:48 AM
My previous experience with anodizing comes from motorcycle parts & packaging equipment. On the bikes, the anodizing certainly does seem to make the parts hold in the heat more. On the packaging equipment, the anodized surface wears much better than bare 6061. The difference in part life is like 3 to 1 over bare aluminum.

Most plating processes will let you decide how thick you want them to be by how long you leave them in the bath. I usually see most plated surfaces spec'd out around .0002" thick. Anodizing is typically much thinner.

Getting a small part anodized at a shop is often not cheap because there is usually a batch minimum charge of around $100 or so. But, if you are not in a rush, you can often find a guy that is willing to quietly add your part to a larger order that is already going through. If you are not fussy about the color, then you can usually get a piggy back ride in a few days or a few weeks. If you want a color that is not black or some other very common color, then you may wait a long time. I've known people to get a piggy back ride on a small part for as little as $5 cash.

This could also be a good opportunity for a group buy type situation.

Gear, thank you for this write up. It's an eye opener. I think that you have a GREAT idea here.