Melting Linotype issue?

I have not found a proper thread to ask this question on Cast Boolits, so I will start here:

I purchase a 70 lb lot of linotype ingots awhile back, and decided to melt down the 3 lb ingots to recast 1 lb ingots because these did not fit well into my Lee 10 lb pot.

During the process, I noticed the linotype alloy melt behaved considerably differently than my previous and extensive 40 year experience with wheel weights, tin and pure lead. First off, the dross was different in that it would stick to the thermometer, then secondly the draw-off nozzle plugged up several times and would not seat properly to shut off the flow. I managed to empty the pot using my ladle.

I decided to put in a 5 lb load of pure lead to see what impact it would have. The sides of the pot cleaned up nicely and the thermometer cleaned off completely. The nozzle worked, but slowly, so I emptied and scraped out every thing I could and cleared the nozzle after it cooled down. I refilled the pot with some of the 1 lb linotype ingots I produced, and subsequent 3 lb ingots eventually caused the same earlier conditions including plugging of the nozzle with slag or dross.

Question: is there something inherent with pure linotype alloy that would cause this condition? It happened at all temperatures above 700 degrees and up to nearly 900 degrees during my experimentation. The top slag or dross did not change consistency with increased temperature and there seemed to be much more quantity than with wheel weights (excluding the clips, of course) and pure lead I would melt down from lead pipes. Same experience with tin melted from beer coils.

Thanks for any help, and if I could be directed to the correct Cast Boolits forum, I will go over there and ask the same questions.

Thanks Jack

I've used lots of linotype and many other alloy mixes, but I'm not sure I've dealt with the problem you're mentioning. On the site you mentioned, scroll down to the " lead and lead alloy" subheading to ask your question. Good luck-

I've read about casting lead being contaminated with zinc and making it unusable, more like oatmeal than molten lead. If indeed that is your problem it can be removed by adding sulfur. Just remember sulfur will ignite and give off some pretty toxic sulfate gases. You would definitely want to be outside and up-wind if you do it.

I run my pot on 800. Could there be a piece of something in the hole? I had to drill one of mine out one size larger to get the flow correct. A fast pour makes a pretty boolit. Pour all of it out and let cool and inspect. Take care if you drill. I broke a small bit in my Lee pot but ended up using it for mixing lube. You can tell the zinc because it is harder to melt--Just spoon it off the top. You need to flux the final mix. I use a small amount of bullet lube. It makes the lead mix like water. When I get through casting I fill and flux the pot for the next time. Let us know the fix. You will get 50 different answers. Go to bottom of this page for more answers.

I've never had that problem. It may be contaminated with another type metal like monotype. I've had issues with monotype. I've run into some foundry type also. There's many types of type metal and identification is iffy and cross contamination common.

Sound as if your Linotype has something else in it. Been using old WW and the nearly pure Pb stick on WW with few pounds of Foundry type. Have a large RCBS pot. I flux with wood shavings and bullet lube. Wood shavings on top keeps mix really nice. Let us know what you find out.

Yes, please keep us posted. Have never had the problem that you have mentioned. I usually use a pound of linotype to ten pounds of lead in my Lee Production Pot. I flux with candle wax. Have never seen your problem before.

AJ

I did a Brinell Hardness Test today, and came up with 7.0 diameter reading indicating 10.7 BH according to the Lee chart. I thought Linotype would be harder than that.

Since I did remelt all 70 lbs of the lot, I'll be interested in seeing if the condition repeats with the 1 lb ingots when I remelt them after selecting an Alloy #2 blend.

I weighed the dross - 3 lbs for the 70 lb lot. Seems high. Most interesting is how the pot and tools cleaned themselves after melting a 1/2 pot of pure lead. I also read that I should not discard the "oatmeal" dross too quickly as it can be reprocessed. Perhaps I had the temp too high, as I read the linotype should melt and pour at 550 degrees F.

The 45 year old Lee pot still drips a little bit, but I can tolerate that.

I did cast about 50 bullets with the Linotype metal, and got really nice shiny and well-formed 175 grain .40 bullets which sized easily after discarding the first 25 which had nasty looking heads. I'm using a 6-cavity mold.

I am unable to post anything on CastBoolits as I have not been approved by the moderators - I just joined.

Thanks for all the input.

Jack

oldvette said:

I did a Brinell Hardness Test today, and came up with 7.0 diameter reading indicating 10.7 BH according to the Lee chart. I thought Linotype would be harder than that.

Since I did remelt all 70 lbs of the lot, I'll be interested in seeing if the condition repeats with the 1 lb ingots when I remelt them after selecting an Alloy #2 blend.

I weighed the dross - 3 lbs for the 70 lb lot. Seems high. Most interesting is how the pot and tools cleaned themselves after melting a 1/2 pot of pure lead. I also read that I should not discard the "oatmeal" dross too quickly as it can be reprocessed. Perhaps I had the temp too high, as I read the linotype should melt and pour at 550 degrees F.

The 45 year old Lee pot still drips a little bit, but I can tolerate that.

I did cast about 50 bullets with the Linotype metal, and got really nice shiny and well-formed 175 grain .40 bullets which sized easily after discarding the first 25 which had nasty looking heads. I'm using a 6-cavity mold.

I am unable to post anything on CastBoolits as I have not been approved by the moderators - I just joined.

Thanks for all the input.

Jack

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Linotype that's worn out will have a lower hardness than the approximate 22 BHN that it should have. Much of what I used to buy years ago was only around 16 BHN, but it was plenty hard for many uses.

If your 10.7 BHN is correct, it's either severely depleted linotype or you have something else altogether. You can alloy and strengthen it or cast with it as is for a number of uses, like handgun bullets.

The lesson I have learned here regarding linotype is to purchase only the "chips" with actual letters on them (or the spacers) and then you can forget the inconvenience of the pigs while having some degree of confidence that you are actually getting real linotype.

I am tempted to buy such a lot off ebay when I see a reasonable deal - perhaps 25 lbs or so - to see how the metal behaves compared to what I just went through.

Jack

I use quite a bit of lynotype to harden bullets. I start my melt an when it melted I stick the lynotype bar in the melt and pull it out when the amount I want is melted. I use the pot-dip and pour method. Way faster than a nozzle pot and no nozzles to clog. I cast with 4 molds in rotation to keep the mold heat down.....Lot of bullets in a short time.

Use a higher temp setting, flux the melted metal, and pour out your smaller ingots.

Keeping simple things simple.

I am probably a bit of a rarity in that I have used Linotype for it's intended purpose. I can tell you it was melted, reused, and partially replenished many times over. All of this done over decades so who knows what's in it.

One thing you can do is buy a bar of Linotype from a known foundry like Rotometals and compare yours to that with the hardness tester. That will give you a comparative reading and also tell how accurate that hardness tester and your method of using it is. You can also compare the two by weight.

I've used lots of linotype. Still do. My impression is that you have something else. What ever it is, sounds like it solidifies at a higher temp than lino or other common boolit alloys.

Heck. Lino melts much lower than lead and you have no problem with pure lead.

Who knows what could have gone into those ingots. You say "slag or dross" is plugging the nozzle. I wonder what could be coming off the alloy as it heats???

I've purposely kept my lino stash in letter form to prove what it is.

I have purchased linotype as newly made ingots from a foundry so there has been no question about contents. The ingots are about 4 lbs. and of a size and shape that is not convenient for my lead pots. My solution has been using a cold chisel to break the ingots into 4 pieces of pretty equal size, then those smaller pieces can be fed into the lead pots as desired to "sweeten" my bullet metal alloys.

As the OP noted, problems in melting linotype seem to occur primarily when using linotype alone. I have experimented with pure linotype bullets for high velocity rifle loads, but all of my regular uses have been with mixtures of wheel weights and linotype. I usually work with alloys from 20% linotype to 50% linotype added to wheel weights, and this is done by melting the wheel weights first, then adding the linotype metal, bringing to temp and blending with the wheel weight metal. This results in an easy process without any problems.

From the studying I have done, linotype metal (84% lead, 12% antimony, 4% tin, trace content of arsenic) is not a true alloy in that the antimony is not melted at the temperatures used, only forming a mechanical mixture within the lead and tin. Colonel E.H. Harrison's great NRA publication "Cast Bullets" describes the metallurgy and investigations of this aspect of use, along with macrographs clearly showing the antimony forming into tiny matrix formations resembling tree branches.

I suspect that may explain what you are seeing when melting straight linotype at the working temps of your equipment.

LoboGunLeather said:

I have purchased linotype as newly made ingots from a foundry so there has been no question about contents. The ingots are about 4 lbs. and of a size and shape that is not convenient for my lead pots. My solution has been using a cold chisel to break the ingots into 4 pieces of pretty equal size, then those smaller pieces can be fed into the lead pots as desired to "sweeten" my bullet metal alloys.

As the OP noted, problems in melting linotype seem to occur primarily when using linotype alone. I have experimented with pure linotype bullets for high velocity rifle loads, but all of my regular uses have been with mixtures of wheel weights and linotype. I usually work with alloys from 20% linotype to 50% linotype added to wheel weights, and this is done by melting the wheel weights first, then adding the linotype metal, bringing to temp and blending with the wheel weight metal. This results in an easy process without any problems.

From the studying I have done, linotype metal (84% lead, 12% antimony, 4% tin, trace content of arsenic) is not a true alloy in that the antimony is not melted at the temperatures used, only forming a mechanical mixture within the lead and tin. Colonel E.H. Harrison's great NRA publication "Cast Bullets" describes the metallurgy and investigations of this aspect of use, along with macrographs clearly showing the antimony forming into tiny matrix formations resembling tree branches.

I suspect that may explain what you are seeing when melting straight linotype at the working temps of your equipment.

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But is it common for the antimony to come out as crystals? If so, how could it have functioned for making print?

max503 said:

But is it common for the antimony to come out as crystals? If so, how could it have functioned for making print?

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No personal experience with type-casting operations, but I suspect that the equipment used was far different than we use as home bullet casters, and the operators were far more experienced and knowledgeable in handling each phase of the operation.

There are other alloys such as monotype and stereotype that contain significantly higher proportions of the hardening metals (principally antimony). It is possible that the OP may be dealing with type metals other than linotype.

For me, the key to the operation is keeping all of the metals suspended in the alloy, and adding the linotype in relatively small increments to a pot of lead at good operating temperatures seems to aid in that. Granted, this is anecdotal and reflects only my own experiences, methods, and equipment. Anything beyond that is territory for experienced typesetters and/or metallurgists, in my opinion.

lead analysis;

linotype lead has not been used in many years. I would be leary to buy "used lead"

Guess I’m very fortunate, friend and I found 300 pounds of Foundry type in an antique mall, all in letters, spacers or designs. LobGunLeather’s procedure is same as mine and have no problems.
Pretty sure whatever the OP has is not pure type.

Antimony in lino is like sugar in coffee. Both are dissolved in solution. I suspect something other than lino. I have bought letters and 21 lb ingots. Lino in large ingots will ring when tapped with metal, lead goes thunk and tin squeaks when bent.

I know some scrap yards will analyze metals. It would be worth it to me to pay and see what you have.