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Bigjohn
10-08-2008, 06:32 PM
G'day to all who read this.

I am placing this information up to help myself and others get some answers.

About a year ago, I was given a LEE 10 pound bottom pour pot; a LEE 20 pound bottom pour pot; 400 kilos of Linotype; 5 boolit molds of different calibres; an almost full container of 'MARVELLUX' and the accessories. The cost to me is a session at the pot to cast one or two hundred .454" round ball when he needs some, which is about every 18 months.

The person who was getting out of casting due to time constraints spoke highly of the 'MARVELLUX' flux as the best around. I have never used it before.

The issues arose when I went to cast the first installment of the required .454" RB. As I had received the pots with metal already in them, I went to the task.

When the metal was fluid I fluxed using 'MARVELLUX' and removed a lot of dross from the pot. During the session, the pouring spout started to drip faster eventually, it started to flow and could not be shut off. I emptied the pot and discovered the sides were heavily caked in dross and rust.

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Obviously, it is possile the previous owner had not cleaned the pots in a long time or that having sat unused for a period of time, moisture crept in between the sides of the pot and lead and caused the rust.
I have not yet checked the 20 pound pot to see what the condition of the sides are.

My questions to the members;
Has anyone here used 'MARVELLUX' as a flux and to what results?

I have searched the forum but not found any cleaning tips for LEE pots (I know there is a thread here)?

Could the period between uses of the pot contributed to this condition? (I have not had this problem with my LEE but I don't use 'MARVELLUX' in them).

The second problem in this saga arose yesterday. To complete the required quota of Round Ball, I set up the gas ring and pot. With the double cavity LEE .454" Round Ball mold, I started casting using the RCBS dipper.

The round ball were dropping from the mold with fins on the sides (at the joint line of course.). This did not happen when I used the Bottom pour pot.

There is no sign of anything keeping the mold halves apart but I will go over it with a magnifer today. The amount of fin varied.

Any tips or hints.

I must close now,

John

Oops! I forgot; my metal on the gas ring was running at about 800+ F and I have no control over it.

Morgan Astorbilt
10-08-2008, 06:51 PM
John, Brownells advertizes that Marvelux doesn't smoke, and prevents rust. I have found the first to be true, but the second definately not. Both my furnaces, which have cast iron liners, constanly rusted between use. I've gone back to using lard. The oily residue on the rim of the pots prevents rust. Any oil will work, some use motor oil soaked sawdust. I used to use the cooking grease my wife collected in jars, mostly bacon fat, but find commercial lard (Armour Brand), bought in food stores, very handy.
Morgan

Cactus Farmer
10-08-2008, 06:58 PM
I used to use the cooking grease my wife collected in jars, mostly bacon fat, but find commercial lard (Armour Brand), bought in food stores, very handy.
Morgan

But lard doesn't make my mouth water. I still want the bacon!

Bigjohn
10-08-2008, 07:00 PM
Morgan, prior to receiving this 'gift', I used fats, wax and oils; basically whatever I could get at the moment I was casting. Even Automatic Transmission fluid.

Never had a problem and at the moment only the pots which I received are affected.

I guess I need to empty the other pot out and go do some serious cleaning; which is my plan for today. Then stick to what I know.

Since I used some in the new cast iron pot yesterday I had better add that to the list.

Part of the problem would occur if 'MARVELLUX' is hydrostatic (Absorbs moisture) as I live in an area where the humidity is normally 60%.

John

Yance
10-08-2008, 07:07 PM
John;

Congratulations on the "score". Hopefully if your friend is using those .454 RB in a muzzleloader you're casting them from pure lead.

As Morgan A. said, Marvelux seems to accelerate rusting rather than prevent it. Most of us use bullet lube, candle wax, (be careful there because of its low flashpoint), rosin, conifer sawdust, etc. All these things help float all the "crud" to the top where it can be removed.

While fluxing be sure th use your old serving spoon and thoroughly scrape the sides and bottom of the pot to loosen and float the dross and rust.

Depending on how badly corroded you pot liner is you may can salvage it (them) by removing the cutoff rod and cleaning it and the inside of the pot with a wire brush. An old smallbore cleaning brush should get the crud out of the spout recess from the top. Turning the cutoff rod in the recess after cleaning will show if the surfaces mate well enough to prevent leakage.

Don't know about Australia, but replacement parts for Lee parts are readily available and quite inexpensive should you liner be in that bad a condition.

The "fins" on the castings are caused by the increased heat from using the gas ring, and the extra pressure exerted by the weight of the metal in the dipper if you're "contact pouring". Try slowing you casting rate down to allow the mould time to cool a bit, and hold the dipper 5 to 10 MM above the sprue plate while pouring.

Junior1942
10-08-2008, 07:52 PM
Stop fluxing. It does nothing for me in 30 years. Take something like a wide-blade screwdriver and scrape the inside of the pot.

Bigjohn
10-08-2008, 08:10 PM
Between searching the streets for a missing cat, the housework etc,. my day is full.

I'm going to go clean both pots shortly. I can start on the 10 pounder while heating up the 20.

LEE equipment is rather expensive here at my end of the line. If I can knock out a couple of the middlemen; I can save a little even when paying the cost of freight to get it here.

I will assess the condition of both pots when I have cleaned them. I their too bad a condition, I will keep them as spares for my 10 & 20 pounders which have not had 'MARVELLUX' in them.

John

runfiverun
10-08-2008, 08:28 PM
marvelux is hyg/droscopic.
however it is spelled. but that don't stop me from using it you really only need a pinch of the stuff. a very small pinch. a salt shaker would help that is what i use let it sit and bubble on top it forms a very nice barrier, once it starts to bubble then i stir and leave the stuff sit on top of my pot unless it is the grey foamy stuff.

Le Loup Solitaire
10-08-2008, 09:28 PM
You don't need to use much of it; a half teaspoon sprinkled on top of the melt. It doesn't really smoke or stink, but it isn't dirt cheap either- it costs. I have been using a 1/4 inch slice of ordinary candle wax which immediately starts to smoke and smell, but tossing a lighted match into it will ignite it. Let it burn while stirring and then skim off the crud/dross that has floated to the top of the melt. One should scrape the sides of the pot when doing this and stir deeply as well. Some folks use a bit of bullet lube, but that is pretty expensive stuff to use for fluxing. There are many other things that can be successfully used to flux the melt as well such as lard and oil-soaked sawdust, bacon fat, etc. Each usually produces smoke and various smells so you would want to do the fluxing outdoors. LLS

Bigjohn
10-08-2008, 10:20 PM
Lunch break.

I've started scrapping the 10 pounder and emptied the 20. The 20 is a newer version so it is not as badly affected.
I do not know if the previous owner cleaned them properly or just cast boolits while they worked; fixing them if they gave troubles.

The 10 pounder is cleaning up ok and should be back together this afternoon. Maybe if I get these done I can go back to doing my casting jobs.

I use various type of implements to scrap the sides and bottom of my LEE pot; has anyone here come up with their own ideas on the prefect implement??

I might try some new designs.
Back to work.
John.

docone31
10-08-2008, 11:03 PM
I am no expert, but, I wonder if inductance is causing the iron oxide to collect.
I have found flakes of oxide in my pots, however I found no evidance of corrosion. I am not saying corrosion is not an issue, however I have found fairly large flakes just clinging. I find them mostly in the corner edge near the bottom of the pot.
Since I use mostly wheel weights and tin, I find a lot of rust in the slag on the melt. It seems a constant issue however small.
Ferrous metals float in lead based melts. Oxides can be prevented from floating by the oxides themselves. The larger flakes do float up in time. I believe the smaller oxide patches do not have the mass to float without assistance. They can be drawn by the inductance of the heating coil.
This is not to say there would be no corrosion. The previous owner might not have excercised melting seperately. Who knows.
When you emptied the pot, was there any porosity in the pot walls? Or evidence of corrosion from oxidation?
I have never used marvelux. I use beeswax, or non acid flux for soldering. I find beeswax works best for me. I am going to try unscented Kitty Litter next. I have read that works fairly well.
It sounds like you scored pretty well there. If the pots last a short time, you are still ahead.
Show us the castings from the molds.
I have used Borax for flux. Odorless, the heat is not enough to liquify it. It seems to gather the slag fairly well. In a bottom pot, the mess on top is not an issue to me. The Borax seems to gather the slag so it can be lifted off, leaving a nice shiney surface. When I have stirred it in, it floats fairly fast without scattering the melt. No silver streaks on the walls.
I have also stirred with a wooden dowel. Smokey, but it does float up the oxide bundles.
Good score, with a small price.

Bigjohn
10-09-2008, 02:45 AM
I've spent the last couple of hours working on both pots. Temporarily gave up on the 10 pounder; the worst affected. The spout is the last item to be cleared and clean; very clogged at present with a combination of lead and dross.

As to the condition of the pot walls the 10lb had some area which were black in colour under the loose material stuck to it. It appears to be cleaning up well with no signs of serious pitting.
I will need to heat up this pot to clear the spout before I re-assemble the pot. Some of the crud I cleaned off the parts held the shape of the item from which it was removed.

As to the 20 pounder, well I cleaned this one out easily and the spout was not badly clogged and cleared without trouble.

After putting this one back together, I warmed it up and put the metal back in then set to casting some LEE 358-158(160)-RFN. Fluxed the mix with beeswax and had a lot of dross (JUNK) come out of the metal.

This was the metal that was in the pot when I received it. I ended up casting several hundred boolits. Some are showing sign of trappped oxides in the boolits which has been dragged through the spout. I've culled out the worst and sort them into practice and competition boolits.

I've refilled the pot and set up for another session tomorrow.

I will try and post some photo's.

Thank you everyone,
John.

1Shirt
10-09-2008, 07:37 AM
Big John, Am somewhat close to Junior's approach, however, I use a wooden dowl, scrape around the sides, and accross the bottom. It smokes and chars, and as it burns down and adds (I think) a bit of carbon to the mix, I just break off the charred part, and lower the dowl a bit. I start with about a 3' about a half inch in dia. dowl or some free for the asking paint sturring sticks. I leave the crud on the top on the pot and stur about every 10-15 min. Works for me, but am sure that others would disagree with my method.

I tried marvelex a few years ago, and after two casting sessions, gave the remaining stuff to another casting friend. He did the same thing, and both of us swore at the stuff and off the stuff. Then went to candle wax until someone turned me on to sturring with a stick.

1Shirt, :coffeecom

Boerrancher
10-09-2008, 09:28 AM
I use to fret and sweat over fluxing and using the proper flux, then finally started tossing a generous pinch of pipe tobacco in the pot every time I added ingots to it. I stir it in good, it doesn't smoke horribly bad, and has a pleasant aroma that doesn't upset the wife. I can go from a pot with lots of oxides floating on the top to a nice shiny alloy with hardly any waste.

Best Wishes from the Boer Ranch,

Joe

Echo
10-09-2008, 02:55 PM
PIPE TOBACCO! My next experiment! Thanks, Joe...

454PB
10-09-2008, 10:39 PM
I'm a pipe smoker......tobacco is too expensive to use for flux!

But, seriously, I've been using Marvelux for 30 years, and in the same Lee pots mentioned in this post. I've had no problems like these, except when using questionable alloys. I was given a bunch of junk alloy from the local lead smelter that apparently had a lot of copper in it. It left the pots looking much like these pictures. It was also a major PITA to clean out. I've since learned that the best way to clean the Lee pots is to fill them with water and then heat them up.

Bigjohn
10-11-2008, 03:28 AM
Yance, yes they are cast from lead and the shooter uses them in a C&B revolver. He has given me a second .454" RB mold but the 'ball' which come from that don't suit his revolver. Slightly different size.

The 10 pound pot is going to require quite a bit of effort on the spout to remove the junk stuck in there.

I have had the 20 pound pot up and running for at least three casting sessions since starting this thread. First effort was several hundred LEE 358-160-RFN from a two cavity mold.

Second and third sessions were today with a LEE 358-160-RFN 6 cavity mold, brand new first use today.

As can be seen from a thread I started in jest in Off Topics

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And as shown above there are a few minor issues with the mold. One is operator error which caused the fins above. The other is a loose pivot bolt for the sprue plate.

The loose plate is causing some fins around the base on the cavities closest to the pivot point.

I'm letting the equipment cool down at the moment before I try and adust it.

John

VTDW
10-11-2008, 10:40 AM
Now THOSE are wings!!! I never smelt in my bottom pour Lee pot. When I do decide to clean the pot I use a wire wheel on a die grinder and it cleans up the crud quite well. I then spray the inside down with WE-40. Once I clean out the spout I then apply a bit of valve grinding compound and spin the rod quite a bit. This finishes cleaning the spout and gives a great seal as well. Permatex #133, I believe is great to coat the rod with. Also, inspect the end of the rod where it seals really well. Sometimes a thin buildup of lead is hard to see.

Dave

Bigjohn
10-11-2008, 08:49 PM
I was given a bunch of junk alloy from the local lead smelter that apparently had a lot of copper in it. It left the pots looking much like these pictures. It was also a major PITA to clean out.

454PB; most lead flashing which I see on the shelves at the hardware stores are now "Copperized". This means from what I can find on the net; the metal has a "Matrix of Copper" built in to stop the sheeting from "flowing" under the effects of gravity.

Also, from information I can find is that copper combines readily with lead as a solution and is very hard to seperate. I am finding a lot of copper coloured residue on the top of ingots from salvaged lead sheeting.

I don't know if others are experiencing this also.

John.