Short answer: These are two mid-band, surface-mix bench torches that land within about seventy dollars of each other, and they solve the same “I’ve outgrown a starter torch” problem in opposite ways. The Carlisle Lucio at $803 is a single fixed flame built for the professional soft-glass flameworker, tuned to run soft and wide on low-pressure natural gas, which Carlisle names as the fuel it works best on. The Bethlehem STACKS at $874 is a modular two-part burner: a small top-mount flame and a larger bottom-mount flame that run independently or together, and can even be bought in stages. If you work soft glass and want one calm, generous flame on house gas, the Lucio fits. If you want two flames in one frame and a soft-plus-boro range, the STACKS fits.
Both are surface-mix torches, so if you are still deciding between architectures, read surface mix vs premix torches first; this guide assumes you already want a surface-mix bench burner and are choosing between these two.
Two torches at a glance
The figures below come from the makers’ own pages where we have them, and are labelled as estimates where they are ours. Configurations and prices change, so confirm the current spec with the maker before you buy.
| Spec | Carlisle Lucio | Bethlehem STACKS |
|---|---|---|
| Price (reference) | $803 | $874 |
| Mix type | Surface mix | Surface mix |
| Mount | Bench | Bench |
| Stages | 1 | 2 |
| Oxygen | ~26 LPM (our estimate) | ~30 LPM (Bethlehem, combined) |
| Glass focus | Soft glass | Soft glass and boro |
| Fuel | Natural gas or propane, best on natural gas | Propane or natural gas |
| Flame layout | One fixed, articulating flame | Two independent flames (top and bottom mount) |
The single most important row is the last one. The Lucio is one flame you aim; the STACKS is two flames you combine. Almost every other difference follows from that.
Surface mix on both, and why that shapes the flame
Both torches keep fuel and oxygen separate until the gases meet at or just past the torch face. Carlisle frames that surface-mix arrangement as a safety feature, since the mixing happens outside the body rather than inside a chamber where a flame front has somewhere to travel. In practice, surface mix also gives you the quieter, bushier, more forgiving flame that soft-glass workers tend to prefer, which is why so much of the soft-glass world lives on these burners rather than on premix.
The Lucio leans into that character deliberately. Carlisle says it runs low-pressure fuel gas and oxygen to produce a soft, wide flame that puts less stress into the glass, which helps avoid cracks and lets an artist work larger pieces. That is a torch tuned for gather-and-sculpt soft-glass work rather than tight, high-velocity detail.
The STACKS is surface mix on both of its heads. Bethlehem describes the top-mount STACKS I as similar to its Alpha burner but with a much sharper flame, and the bottom-mount STACKS II as similar to its Bravo, matching that burner’s flame width and BTU output, but without the Bravo’s center flame. So one torch gives you a sharp small flame and a wide large flame from the same stand, each with its own character.
Fuel choice: the natural-gas-friendly Lucio vs the propane-or-natural-gas STACKS
Fuel is where these two diverge in a way that can decide the purchase before anything else.
Carlisle states the Lucio uses either natural gas or propane, and works best with natural gas. If you have natural gas plumbed to your studio, that is a real advantage: the Lucio is designed to give its soft, wide flame on low-pressure house gas, so you are not fighting the torch to get the flame it was built for. The catalog lists the Lucio’s fuels as natural gas and propane only, with no hydrogen.
The STACKS runs propane or natural gas as well, and Bethlehem publishes low-pressure operating figures for the STACKS I top mount: gas at 2 to 5 psi and oxygen at 8 to 20 psi. Those numbers are for the STACKS I only; do not extend them to the STACKS II or to the Lucio, whose maker publishes its own guidance. Carlisle does not publish a single Lucio pressure table on the product page, so for the Lucio the rule is the standard one: the manufacturer’s manual sets your pressures, and no guide, this one included, overrides it.
The practical read: if your bench is on natural gas and you work soft glass, the Lucio is built around exactly that combination. If you are on propane, or expect to move between fuels, both torches support propane and the choice comes down to flame layout rather than fuel. For the wider trade-offs between the two fuels, see propane vs natural gas for torchwork.
Oxygen demand and running on a concentrator
Oxygen is an estimate here, not a headline spec, and the two torches are labelled differently on purpose.
For the STACKS, the numbers are Bethlehem-published. Bethlehem lists the STACKS I at 10 LPM of oxygen at full flame, on 6 gas jets, and the STACKS II at 20 LPM. The catalog’s ~30 LPM reference for the STACKS is the arithmetic total of both burners at their published full-flame rates, so it describes running both flames at once, never a single flame. If you run only the top mount, you are in 10 LPM territory; only the bottom mount, 20 LPM; both together, around 30.
For the Lucio, ~26 LPM is our owner-judgment estimate, placed against comparable torches, not a figure Carlisle publishes. Treat it as a rough sense of appetite for a mid-size soft-glass flame, not a manufacturer spec, and confirm your real supply against the flame you actually run.
On concentrators, the STACKS has an explicit answer and the Lucio does not. Bethlehem says both STACKS heads work well with oxygen concentrators and excel on low-pressure systems, and that any concentrator producing a minimum of 5 LPM at 5 psi can be used on its Alpha, Bravo, and STACKS torches. That is a helpful floor, but note the scale: a single small concentrator will not feed both STACKS flames at their combined 30 LPM at once, so concentrator users should think in terms of which head they run, or plan multiple concentrators or tank oxygen for the full two-flame output. For how to size an oxygen supply to a torch, see oxygen concentrator vs tanks for lampworking.
Editor’s note: the STACKS oxygen figures (10 LPM STACKS I, 20 LPM STACKS II, roughly 30 combined) come from Bethlehem’s own pages and are labelled as such. The Lucio oxygen figure is our estimate, not a Carlisle-published number. Where a figure is safety-relevant, the manufacturer’s manual for your specific torch takes precedence over anything here.
One fixed flame vs two modular burners
This is the heart of the decision.
The Lucio is one flame. Its burner is fixed to a Mini CC base, the same base used under Carlisle’s Carlisle Mini CC, and the head articulates on a ball joint so you can angle it to your work; the base has drilled ports for bolting it to the bench. You get a single, well-tuned soft-glass flame that you aim and adjust. It is simple, and for a soft-glass artist who wants one dependable flame, simple is a feature.
The STACKS is two flames in one frame. Bethlehem built it as its first mid-range, mid-priced bench burner, developed over about two years to fill the gap between its Alpha and Bravo. It ships as a Top Mount “Sharp Flame” surface-mix burner (STACKS I) plus a Bottom Mount “Bravo”-sized surface-mix burner (STACKS II) on an adjustable STACKS base, with a cleaning kit and a lifetime factory warranty. Each burner has its own B-fitting gas and oxygen connections and runs independently, so you can switch between a sharp small flame and a wide large flame, or run both at once, without changing torches.
There is a purchasing consequence too: the Top Mount and Bottom Mount can be bought separately. That is why Bethlehem’s published price range for the STACKS starts well below the complete-unit figure; a buyer can acquire it in stages, starting with one head and adding the other later. The Lucio has no such staging; it is one torch at one price. If you want to spread the cost or start with just the flame you need now, the STACKS gives you that option and the Lucio does not.
Soft glass focus vs mixed soft-and-boro range
The catalog marks the Lucio as a soft-glass torch, and Carlisle positions it squarely at soft-glass sculptural work of all sizes, with the low-pressure flame chosen specifically to reduce stress in larger soft-glass pieces. If soft glass is your material and larger sculptural work is your direction, that focus is exactly what you want. If you later need even more flame for very large soft glass, Carlisle’s step up is the Carlisle Lucio Grande, which adds a row of ports; it is a bigger, more expensive torch, not the same one, so treat it as the next tier rather than a variant.
The STACKS is catalogued for soft glass and boro both. Its two flames give it more range across work sizes in one purchase, and the sharp top-mount flame in particular opens up tighter and harder work than a single soft-glass flame handles comfortably. If you know you work, or want to explore, both soft glass and boro, the STACKS covers more ground without a second torch.
Price and what is actually in the box
Both sit in the mid price band, close together: the Lucio at $803 and the STACKS at $874. What that money buys differs.
- Lucio: one surface-mix burner on a Mini CC base with a ball-joint articulating head and a base drilled for bench mounting. One flame, ready to run.
- STACKS: two independent surface-mix burners (Top Mount and Bottom Mount) on an adjustable stainless base, built from stainless steel with Bethlehem’s stainless-steel modular needle valves, plus its own oxygen hose, B-fitting gas connections, a cleaning kit, and a lifetime factory warranty. Two flames, and the option to have bought them one at a time.
So the STACKS’s complete-unit price buys two flames and a warranty; the Lucio’s price buys one flame purpose-built for soft glass on natural gas. Neither is “more torch” in the abstract; they are different shapes of torch at a similar price.
One honest caveat on numbers: Bethlehem’s own materials conflict on the STACKS II jet count (one listing cites 18 jets, and other Bethlehem materials differ), so the catalog leaves the STACKS total jet count unrecorded pending confirmation. The STACKS I is consistently described as 6 sharp-flame jets. We do not publish a single STACKS jet total, because the maker’s own sources do not agree on one, and inventing a tidy number would be worse than leaving it open.
Which torch fits which buyer
- Buy the Lucio if you work soft glass, especially larger sculptural pieces, and you have natural gas at the bench. It is built for exactly that: a soft, wide, low-stress flame on the fuel Carlisle says it runs best on, in one simple articulating package.
- Buy the STACKS if you want two flames from one stand, a sharp small flame and a wide large one, a soft-plus-boro range, or the ability to buy in stages and add the second head later. Its concentrator-friendliness and published low-pressure figures are a bonus for home studios, as long as you size oxygen to the head or heads you actually run.
- Either way, match the torch to your oxygen supply and your fuel first, then follow the maker’s manual for pressures and setup. For a wider soft-glass field, see best soft glass lampworking torch; for a head-to-head with a different large burner, see the Nortel Red Max vs Bethlehem STACKS comparison.
Related guides
- Best soft glass lampworking torch
- Surface mix vs premix torches
- Propane vs natural gas for torchwork
- Oxygen concentrator vs tanks for lampworking
- Nortel Red Max vs Bethlehem STACKS
Sources
- Carlisle Machine Works, “Lucio” bench burner page: http://carlislemachine.com/as_benchburners/lucio.php
- Carlisle Machine Works, “Mini CC” bench burner page (shared base): http://carlislemachine.com/as_benchburners/minicc.php
- Bethlehem Burners, “STACKS” torch page: https://www.bethlehemburners.com/torches/stacks/
- Bethlehem Burners, “STACKS bench burner” announcement: https://www.bethlehemburners.com/news/bethlehem-burners-stacks-bench-burner/
- Bethlehem Burners, “Technical Information” (STACKS I operating figures): https://www.bethlehemburners.com/resources/technical-information/
- Bethlehem Burners, “Oxygen concentrator questions”: https://www.bethlehemburners.com/news/oxygen-concentrator-questions/
Editor’s note: model names, specs, and prices reflect public manufacturer information as of 2026, and some figures (notably the STACKS II jet count) vary between the maker’s own sources. Verify the current configuration, pressures, and price with Carlisle or Bethlehem before you buy.