reusing slugs in Ludlow

Midwest Ephemera
on 28 Nov 24 (14:46)

I just got a Ludlow up and working, and while I do have a couple pigs of the correct alloy, I also have a bucket of (old but clean) cast slugs I’d love to use to replenish the pot occasionally…

From my understanding, it was common practice to clean and re-melt Ludlow slugs after use, and I know foundry type and Monotype is harder and bad for the machine, but is pretty much any other linecast slug (Linotype, etc) and/or leading safe to use?

Anyone know of a photo or drawing resource identifying slugs from different casters? Seems like they’d be easy enough to identify based on the size and shape of the molds but I can’t find anything anywhere.

Thanks!
Bryan

Midwest Ephemera
on 28 Nov 24 (15:05)

for reference, these seem to be the different variations i’ve got in my bucket, left is ludlow, next is a piece of leading, I think the right is Linotype, right? what are the others?

IMG_2562.JPG

mikefrommontana
on 30 Nov 24 (11:58)

I’ve been remelting slugs for years, so unless things are really dirty, you should be fine. Linotype/Intertype use the same metal as Ludlow. The slugs you show are (left to right): Ludlow, random leading (not linecast), the others are Intertype, either cast on a recessed mold (center and center right) or non-overhanging text as on the right end.

The most important thing is to keep you metal levels up over the pot well rim (and certainly over the elements!) And to use Lubriclean when coating the plunger after cleaning (Vitaflux causes oxides to form faster).

mikefrommontana
on 30 Nov 24 (11:58)

Updated 30 Nov 24 (12:10)

Algorithm fail #1

mikefrommontana
on 30 Nov 24 (11:58)

Updated 30 Nov 24 (12:11)

Algorithm fail #2 Looking forward to the new site!

Midwest Ephemera
on 30 Nov 24 (23:02)

Updated 30 Nov 24 (23:03)

Rad, thanks a bunch Mike! Yes, the hopes and dreams of the letterpress world are resting on the new Briarpress site. : )

Got a bunch of casting done today and I’m getting the hang of it, I just wish I could fit it in the shop, because it did not enjoy running in my freezing garage today. Took much longer to melt the water than it did to melt the pot. I checked with Dave Seat and he recommended half (cheapo) antifreeze and half water, with a half-pint of the soluble oil (just in case anyone ends up searching Briarpress for “ludlow anti-freeze” like I did this morning).

mikefrommontana
on 30 Nov 24 (23:11)

Updated 1 Dec 24 (16:36)

My model M has been running with a pond pump circulating RV anti-freeze. On model Ls with the integral pumps, anti-freeze is a must to prevent pump or tank damage. Even when really cold, it should take your machine about an hour to melt out for casting.

mindhue
on 1 Dec 24 (16:53)

Note about remelting slugs:

I was told by Dave Seat that reusing cast slugs is okay to a certain point, but to keep the metal in your pot at the correct alloy percentages you will need to add pig metal from time to time. When you dross the pot you’re actually removing some of the antimony that has come out of solution with the lead, so over time the alloy will skew more and more to lead.

The practical upshot of that is if you’re adding old slugs from random sources there’s a reasonable chance they were cast at or near the proper alloy, so you should be okay, but if you keep adding your own metal to the pot over and over again things will get wonky.

I know the folks at the Museum of Printing in Haverhill, Mass got a remelter working and found a quantity of plus metal, which is the additive you use to correct the alloy of the recycled metal you use to cast pigs. Since I’m in Boston it’ll be easy for me to get new pigs from time to time and trade in my old slugs for reconditioning, but I think they’re hoping to offer mail service to those “in the trade”.