Super caster: 1...3 point leads not fusing

[Christophe Slychan]

Hi,
I'm trying to cast thin leads with the 77,000 series mould on a super caster. The problem is that the increments don't fuse properly - it looks like the lead cools down too fast.
I'm running the machine at ca. 120rpm, lead temperature is around 700°F and there's barely any water flow through the mould to keep it hot. Unfortunately it doesn't help - leads fuse only occasionally, the product is very brittle.
I took extra care to adjust the jet block in the casting position so that the slot is exactly between the mould sideblocks, and I also adjusted the micrometer wedge so the slot is centered length-wise. No effect.

Does anyone have good experiences casting this kind of product?


By the way, neither the instructions in http://www.metaltype.co.uk/downloads/mono_rule.pdf nor the 1952 super caster manual don't mention a very important part: a mould blade connecting link. It's necessary to cast the thin leads (otherwise the mould blade is too far to the left and doesn't push the product past the jet block slot) and must be installed before the mould or its movable sideblock is put in place.

[Christophe Slychan]

Problem solved! The caster was turning slower than I expected.
The machine was in its second gear (i.e. 10...60RPM) while I thought it was turning at ca. 100rpm after cranking the Varigear up to the maximum of the RPM meter.
I couldn't shift the gears earlier as all three levers were stuck... I got them to move after diving into the gearbox and tapping two rods with a hammer. Now I can change gears and after getting "proper" 105...110RPM the machine casts leads quite nicely.

Next step: 3-point leads, 1-point leads, then rules, FFRs (fully-faced rules) etc.

[Dan Jones]

Congratulations Christophe, I have only done 12 pt. strip material so far. Thank you for the tip about the mould connecting link too, as they say "the Devil is in the details". I have wanted to cast full face rules (FFR) in 12 pt. or 18 pt., I have the matrices, however my kit does not have the FFR attachments. Duncan at the Type Archive says they are essential to casting. I am interested in hearing about your success and why the FFR pieces are required.

Dan 

[Christophe Slychan]

The strip material moulds could be used for casting:
-low leads (the same height as a low space/quad),
-high leads (the same height as a type body without character), usually for supporting long ascenders/descenders or for casting ornamental lines (with a matrix above)
-and finally FFR - whose height is the same as the "normal" type has, and the whole surface will be printed. So, a 12 or 18pt FFR would give you a very thick straight line.

There were also TUS ("tie-up slug") mould accessories, but I don't see why that would need any special equipment. You can use normal leads for tying up your type.

Some moulds had equipment for FFR and others did not, it was marked on the box.
The equipment included mould blades, replaceable sideblocks (at least for 1...3 points - I don't remember if 4...18 had them as well) and a flat upper blank matrix.