Identifying Types of Type-Metal

[grumpy one]

When I buy type-metal from the local scrap dealer he calls it “printers’ lead” and doesn’t get too specific as to what kind it is. A couple of days ago I bought out his stock – 100 pounds at 47 cents a pound. A small amount of it was in the form of narrow flat strips two to four inches long. These were produced by a linotype machine. The rest was individual letters or small rectangular blocks. They would either have come from a monotype machine, or been "foundry type" - a much harder alloy that isn't as easy to cast.

To find out what I had, I melted 8 pounds of it. The solidus temperature (when it changes from solid to mushy) was less than 500 degrees F, as expected. The liquidus temperature (where it changes from mushy to liquid) was 625 degrees F. I looked that up under Ternary Alloys at this URL:
http://home.iprimus.com.au/billlize/page40.htm
The nearest match was the hard grade of foundry type, which should have melted at 620 degrees F. Well, my thermocouple readout hasn’t been calibrated since 1977 and wasn’t a super-special one in the first place, so that’s near enough. Looks like what I have is 12% tin, 23% antimony, and 65% lead. BHN when air-cooled should be 33. However I already know that I don’t want to cast this stuff. I find I have to pour it at 900 degrees F or more, and while the bullets fill out well, most of them have a cloudy area on the nose. I’d rather be able to cast at about 750 to 800 degrees F, so I will have to dilute the mix a bit. All I did was add one and a half pounds of lead sheet to my 8 pound batch, and found that dropped the liquidus temperature to 550 degrees F. If I’d had any WW I’d have used that instead of sheet lead, but I didn’t have any. Simple calculation says I now have 0.96 pounds of tin, 1.84 pounds of antimony, and 6.7 pounds of lead in the pot. In other words my small sample batch of home-mixed alloy is now 10.1% tin, 19.4% antimony, and 70.5% lead. I know from prior experience that the alloy that melts at 550 degrees F will give me good bullets with a 750 degree F casting temperature. Referring to the alloys chart at the above URL, the alloy's composition is now very close to the softer grade of foundry type, which is 30 BHN air cooled. Of course I could add more lead or WW to make it softer if I wanted to, but I know I can cast this alloy and get good results. I do want to get uniform results, though, so I need to be consistent in how much lead I add to the other 92 pounds of type metal I bought.

I don't know if it is the same in the US, but that scrap dealer was really glad to sell me the type metal. He says if he just had some way to get the antimony out, the lead would be valuable, but nobody wants this stuff with so much antimony in it. Nobody except me, that is.

[454PB]

Years ago, I was given 3000 pounds of exactly what you describe. Some of it in the narrow strips....about 1/8" and up to 5" long, mixed in with the bigger blocks.....up to 1 1/4" square. Since I got this stuff, I've called it linotype. I just dump it all together and melt it down. I use anywhere from straight "linotype" to mixtures of 25% lino to 75% wheelweights and 50/50 lino to wheelweights.

Here is what I find: the pure stuff tests 21 BHN (random sample). My old wheelweights mixed 75% to 25% linotype measure 17 BHN. This is pretty much what I would expect, given the available published information.

The results you report indicate your type metal is a lot higher in antimony than mine, even though the physical description is the same.

Some of that 3000 pounds I mentioned was in 10 KG ingots, which I have read is the really pure reconsistuted alloy.

My batch also contains a lot of copper strips that I assume was used as spacers during the type setting procedure.

I'm going to take some digital pictures of my stuff and put it here, can you do the same?

[grumpy one]

I didn't even think about pictures, I just melted it all down and poured it into Lee one-pound ingots, mostly without alloying it. When I bought it at least three quarters of it was in single-letters, so they were quite tiny pieces, say about an eighth of an inch by a sixteenth of an inch, and maybe an inch deep. According to some websites I checked, single letters are always monotype or factory type, while linotype is always in strips of one line of print. I was pretty sure these would turn out to be factory type, not monotype because they were very old and very, very black. I think they'd been reused lots of times. The long strips - linotype - were all shiny silver.

As far as I know the only way to tell what you have, is to measure the liquidus temperature. If I had a hardness tester that would be useful too, but I don't have one.

I've bought a few batches of these single-letters before, so I've got about 180 pounds of one pound ingots now. My plan is to check the liquidus temperature when I melt each batch in the ten pound Lee pot, and add enough soft alloy to bring it down to 550 or 575 degrees F. I did make one batch of 500 311291 with this stuff previously. Half of them I left the alloy as it came, and half I cut it back to reduce the casting temperature a bit, but didn't keep track of what I put in. Both batches of bullets were fine, but the first batch had to have the very high casting temperature, and had cloudy patches on one side of the bullet nose.

[jar-wv]

Pictures would be nice, as I'm not sure what linotype or monotype even looks like. I've asked for it at the scrap yard, and told them I think it looks like small backwards letters, but they just throw it all in with the lead and say they "think" there's some of it in the bottom of the 4x4 cardboard bin. One guy even showed me a number like is on a house address and said it was lino. Pictures Ive seen on ebay show small individual letters. I've also seen rather large looking bricks of some sort of alloy there. Anybody have a quess as to what that may be? All I've been using so far is WW, and all I'm going to cast will be pistol bullets.

jar

[454PB]

OK, I just took some pics of my various forms. You will see that one piece is still attached to the wood used in the process, and some of the copper spacers I mentioned.. I also laid one of my Lyman 452651 330 grain .454 boolits along side for scale. You can click on the picture for a larger version.
1578

[Bucks Owin]

In the Jan, 1958 issue of AR, here's the rundown:

Type Metal...... % Tin........ % Antimony....... % Lead........BHN

Electrotype.........3.0.............2.5........... ...........94.5.............12
Linotype.............4.0.............12.0......... ...........84.0..............22
Stereotype.........6.0.............14.0........... .........80.0..............23
Monotype...........9.0.............19.0........... .........72.0..............28


Hope this helps,

Dennis :Fire:

BTW, the linotype that I get from a retired printer is cast in large ingots of about 40 lbs with a "ring" cast in one end to suspend the ingots on a rack of some sort....

[grumpy one]

In 454PB's picture, the long silver strips are classic linotype. The linotype machine makes print in full lines, which are probably 4" long on average, depending on the page layout they were made for. The other blocks in his picture are special items, and could have been made out of any typemetal. However such items are often made by a factory rather than a local printer, and if so they would be likely to be factory type. If the printer made them himself he might have preferred to use linotype, if he wasn't going to run all that many copies from the block, because linotype is easier to cast. To find out what they are made from, all you need to do is melt a few pounds of them and measure the liquidus temperature. If it is 462 degrees F, they are linotype.

The ingots Dennis has described are standard linotype ingots. They were hung by the loop end above the molten metal pot of the linotype machine, and they lowered automatically to keep the level of molten metal in the pot constant as linotype was used up. I visited a newspaper and watched whole rows of these machines in simultaneous action back in the early 1950s. I haven't seen a monotype machine, but it may have used similar ingots. Factory type is not made by a fast automatic machine like a linotype or monotype machine, and I've no idea what the ingots of factory type would have looked like.

In case anyone is interested, I just worked out that if I wanted to convert my 180 pounds of hard factory type into linotype, I could do it by just adding 260 pounds of WW to it. I'd end up slightly high on tin (5.3% versus 4%) but that is a problem I could live with.

[buck1]

I got some foundry type a wile back. 1part type to 7parts WW will in 10 days be BHN 15, and cast like water. This also makes the most of the tin. FWIW....Buck

[grumpy one]

Thanks Buck - that mixture would be 1.9% tin and 6.4% antimony, which sounds like a pretty nice alloy. Now all I need is a source of WW here in Melbourne.

Geoff

[454PB]

See the big "O" in the picture? I did a hardness test on it and it was 27 BHN. I then did one on the "$", and it was 21 BHN. You would go nuts hardness testing this stuff, so a temperature test or at least a test of a large batch averaged is the answer. I'm sure not going to sort this stuff out! The boolit in the picture was cast of 75% WW and 25% this linotype, and it measures 17 BHN. If you look real close, you can see the test dimple on the boolit nose.

[grumpy one]

Each time you start out to cast a batch of bullets, always melt the typemetal first. If you just check the liquidus temperature of that random mixture of various kinds of typemetal you've dumped in the pot, you can figure out what is the average composition of what is in the pot, and that will tell you how much WW to add to that particular batch. You can make up a sort of approximate check sheet relating liquidus temperature to antimony content, using the information at the URL I quoted previously.