Best Lathe Torch for Glassblowing: Fire-Carriage Burners and Hand Torches

Short answer: There is no single “lathe torch.” Glass-lathe work is done two ways, and the torch you want depends on which one you run. Either a dedicated burner rides the lathe’s fire carriage, a movable head that raises and lowers to the tube diameter and rolls along the work, or you clamp a premix hand torch to a ring stand or fixture and feed the glass into it by hand. For most lathe, seal, and scientific work the flame you want is premix, and the catalog picks are the Nortel Unitorch built specifically for lathe and seal work, the National 3A-B premix hand torches, the Herbert Arnold Premix Hand Torch, the Carlisle Universal Hand Torch, and Carlisle’s GR combination head, which bolts onto a lathe fire carriage.

This guide is about the torch. For the lathe itself, the carriage, the headstock and tailstock, and what a lathe setup costs and demands, see the glass lathes guide; this article does not repeat it.

What people mean by a “lathe torch”

A glass lathe holds a length of tubing between a rotating headstock and tailstock and spins it while you heat and shape it. The heat comes from one of two arrangements, and “lathe torch” gets used loosely for both.

The first is a fire-carriage burner. The lathe carries a movable carriage that raises and lowers to match the tubing diameter and rolls back and forth along the tube, often with an adjustable jet angle. A burner made for this mounts on the carriage, is fed by remote valves rather than valves on its own body, and sits in one place while the glass turns in front of it. This is the setup used for larger vessels, long seams, and heavy scientific apparatus.

The second, more common in small shops, is a hand torch clamped to a stand. Many glassworkers fix a premix hand torch to a ring stand or a shop-built fixture, light it, and feed the spinning glass into a stationary flame. It costs far less than a purpose-built fire carriage and, for seals and joints on tubing that fits the flame, it does the same job. Both approaches are normal practice, and which one you choose is a question of scale and budget more than of technique.

Why premix dominates lathe and scientific work

Torches mix their gases one of two ways, and the difference decides what a flame is good for. A surface-mix burner keeps oxygen and fuel separate until they meet at or just past the face, giving a broader, softer, lower-velocity flame that is best when a large area needs heating. A premix torch combines gas and oxygen in a chamber inside the body, burns a little hotter, and throws a very concentrated flame. Premix is the flame you reach for when making seals and heating small, concentrated areas, which is exactly what lathe seams, ring seals, and graded seals ask for. That is why premix hand torches dominate scientific and lathe work.

Premix torches also take interchangeable tips, so one body covers a broad range of flame characters: a fine tip for a small seal, a broader tip to preheat a larger piece. That tip system is central to the National, Herbert Arnold, Nortel Twin Fuel, and Carlisle Universal hand torches. For the full comparison, see surface mix versus premix torches.

The lathe and scientific torches in this guide

Every model below is drawn from our catalog; mix type, mount, and price come straight from each model’s catalog record, which tracks the maker’s own published specs.

Editor’s note: Prices are reference figures. They come from the manufacturer’s own pages and price lists where we have them, and are labelled as estimates where they are ours. Confirm the current figure with the maker before you buy, since tips, hoses, and carriage or mount hardware all add to the base price. Where a model is built to order, the maker does not publish a fixed price.

Nortel Unitorch: the six-tip torch built for lathe work

The Unitorch is the one torch in this guide made for exactly this job. It is a premix hand torch about 17 inches long and roughly 1.5 lb, carrying six stainless-steel tips, and Nortel lists it for lathe work, dewars, fritted discs, round bottoms, ring seals, graded seals, glass-to-metal seals, and flame cutting. Nortel says it easily works 40 mm quartz or 75 mm borosilicate standard-wall tubing. Clamp it to a stand or work it by hand into a lathe-held piece, and it does the concentrated, repeatable sealing that lathe work runs on.

It is important to place it correctly: the Unitorch is a scientific hand torch for intermediate to advanced work on boro and quartz, not a beginner soft-glass torch, and it should never be read as one. The family scales up when you need more fire or more distance from it. The Unitorch-9 adds a nine-tip head at roughly 20 inches, which lets you stand back from an intense, narrow band of flame; the Unitorch-12 carries twelve tips on a stainless manifold at about 2 lb. Both run the same scientific task list. Neither has a published price recorded in the catalog; treat them as built to order and confirm with Nortel.

National premix hand torches: tip-driven and proven

National Torch, a current brand of Premier Industries made in the USA, builds the workhorse premix hand torches of this category. The 3A-B is a premix hand torch with a rotating leak-proof O-ring union, listed for city, natural, mixed, propane, and butane fuel gases with either oxygen or compressed air. The key point for lathe work is that flame size and oxygen use depend on the installed tip, so there is no single flow figure for a 3-series National; you keep a set of tips and change the flame to the seam. The 3B-B is the same torch with 9/16-18 B-size threaded hose fittings and a union that rotates the tip-and-elbow assembly to any angle without a wrench, useful when a torch is fixed to a stand and the work comes to it.

The 4B is the industrial model, shipping with a 1/4-inch NPT by 7-inch elbow and B-size hose connections and running N-4, N-6A, and P-Series tips for propane and natural gas with air. National markets it as industrial rather than the bead-oriented 3-series, so it is the one to look at when your tubing and seams run heavier.

Herbert Arnold hand torches for seals and quartz

Herbert Arnold builds the precision end. The Premix Hand Torch, model 126/22, is a brass-bodied premix torch with precisely adjustable needle valves, one for propane and one for oxygen, and an exchangeable upper part fixed by a screwed swivel nut for interchangeable jets. It ships with three stainless groove jets (0.8, 1.0, and 1.3 mm) and is built as a sealing burner producing very sharp, hot flames, which is precisely the flame a fine ring seal or graded seal wants. Herbert Arnold also builds industrial quartz burners with electro-polished stainless gas parts and quartz-glass jets, so a quartz-heavy shop can look past the hand torch. The hand torches are propane only; confirm your fuel against the model before buying.

Carlisle: the Universal hand torch and the GR fire-carriage burner

Carlisle covers both sides of the lathe question. The Universal Hand Torch is a versatile premix hand torch offered with a 1/4-inch or 3/8-inch nozzle, plus Shorty, High-Capacity, and Unecon configurations. Clamped to a stand it is the value premix option among the purpose-built shop hand torches here.

The GR is the fire-carriage answer. It is a combination head with an independently controlled premixed center fire inside a surface-mixed outer fire, running oxygen with natural gas, propane, or hydrogen. Its short body carries no valves of its own; it is fed by remote valves such as a VMB-4, the head can be water-cooled, and, critically for lathe work, the base removes so the head bolts onto a lathe fire carriage. That is what makes the GR a bench-or-lathe burner rather than a hand torch: it is designed to sit on the carriage and heat the turning glass. Our catalog records the GR’s mix type as surface; Carlisle’s own description of the combination head is the premixed-center, surface-outer arrangement above, so treat the flame as a combination and confirm the configuration with Carlisle. It has no published price recorded; treat it as built to order.

Matching the torch to your glass and your setup

A few decisions settle which torch fits:

• Quartz and fused silica work far hotter than boro or soft glass. Hydrogen with oxygen is common for quartz; community guidance gives a rough 5 to 10 psi starting point and notes propane and oxygen may suit smaller or thin quartz, but the manufacturer’s manual settings take precedence over any general figure. The Twin Fuel Handtorch and the Carlisle GR both list hydrogen; the Unitorch and National hand torches, as recorded, do not. See best torch for quartz.
• Boro tubing is the Unitorch’s stated home (up to 75 mm standard wall) and the 4B’s industrial range. Seal size, not just tube diameter, drives the tip choice.
• Fire carriage or clamped stand. For a full lathe with a carriage, the GR is built to mount on it; to feed work into a fixed flame, any of the premix hand torches clamps to a stand.

Editor’s note: Oxygen demand on these premix torches is tip-dependent, so the catalog records no fixed oxygen flow for the National hand torches, the Nortel Unitorch or Twin Fuel, the Herbert Arnold hand torches, or the Carlisle Universal. Oxygen here is an estimate set by the installed tip, not a fixed spec. Plan your tip set with the torch and expect no single number to describe the whole burner.

Mounting, gases, and safety

Because these are premix torches, or a combination head with a premix element, the details that decide fit live in the maker’s manual. Confirm the fuel gas the torch runs, confirm whether it takes oxygen, compressed air, or both, and plan the tips or jets alongside the torch, since in this class the tip is half the tool.

Premix torches carry a real flashback path because the gases are already mixed inside the body, so the flashback protection your torch and gas supply call for is not optional. Follow the manufacturer manual for pressures and for the protection they specify, and never copy a figure from another torch. See flashback arrestors explained for how placement works, and let the manual set the numbers. A fire-carriage burner adds one more requirement: the burner, its remote valves, and any water cooling must be plumbed and mounted to the maker’s spec before the lathe turns.

Related guides

• Glass lathes
• Best scientific glassblowing hand torch
• Surface mix versus premix torches
• Best torch for quartz
• Flashback arrestors explained

Sources

• Scientific Glassblowing Learning Center (ILPI), burners tutorial: premix versus surface mix, tips, and lathe work
• Scientific Glassblowing Learning Center (ILPI), burner reference
• Nortel, Unitorch Handtorch product page
• National Torch (Premier Industries), hand torch pages
• Carlisle Machine Works, GR combination burner page
• Herbert Arnold, burners overview