Acetylene is one of the most common gases used for welding, cutting, and brazing. When portability and convenience matter—especially for quick jobs or on-site work—the MC size acetylene cylinder stands out as a popular choice. But what exactly is it, and when should you use it? This article covers everything you need to know.
What Is an MC Size Acetylene Cylinder?
The MC size acetylene cylinder is a compact gas bottle designed for small-scale metalworking applications. Originally known as a “medical cylinder” (hence the “MC”), it’s now widely used in trades like HVAC, plumbing, and automotive repair.
Here are the typical specs:
- Gas Capacity: Around 10 cubic feet
- Height: About 15 inches (38 cm)
- Diameter: Roughly 4 inches (10 cm)
- Full Weight: 7–10 lbs (3–4.5 kg)
- Fitting: CGA 200 valve
- Material: Steel shell with porous mass filled with acetone to safely hold acetylene
It’s a popular option for those who need something lightweight and easy to transport—especially in tight workspaces or on ladders.
| Specification | MC Size Cylinder |
|---|---|
| Gas Capacity | ~10 cubic feet (0.28 m³) |
| Height | ~15 inches (38 cm) |
| Diameter | ~4 inches (10 cm) |
| Full Weight | 7–10 lbs (3–4.5 kg) |
| Valve Connection | CGA 200 |
| Cylinder Material | Steel with porous filler & acetone |
| Maximum Pressure | ~250 psi (17 bar) |
| Recommended Use | Light-duty torch applications |
Where and How It’s Used
The MC cylinder is ideal for light-duty tasks. You’ll often see it used in:
- HVAC service calls
- Small automotive repairs (like exhaust pipe brazing)
- Metal artwork and hobby welding
- Field repairs or minor fabrication tasks
- Plumbing installations
Because of its limited gas volume, it’s best for short or occasional jobs. If you’re working all day or doing heavy-duty cutting, you’ll want a larger cylinder.
Pairing It With the Right Equipment
MC cylinders are commonly part of portable oxy-acetylene torch kits. These kits usually include:
- An MC acetylene cylinder
- A matching oxygen cylinder (often 20 cu ft or “R” size)
- Torch, regulators, and hoses
- Carrying case
Well-known brands like Victor, Harris, and Uniweld all offer compatible kits. Just make sure the torch and regulator fit the CGA 200 valve used on MC cylinders.
Buying, Refilling & Exchange Tips
You can get MC cylinders from most welding gas suppliers—either by purchasing outright or through a cylinder exchange program.
- New Cylinder Purchase: $60–$100
- Refills/Exchanges: Usually $20–$35
- Where to Get Them: Airgas, Praxair, or local welding supply stores
Exchange programs are convenient. You simply return your empty cylinder and receive a full one—no waiting for refills.
Storage and Safety Guidelines
Even though it’s small, an MC acetylene cylinder must be handled with care:
- Always store upright in a cool, ventilated place
- Keep away from flames, sparks, and electrical sources
- Use caps during transport
- Never use a cylinder that appears damaged or has been dropped
Remember: acetylene is unstable under pressure and is only safely stored in a dissolved state inside the cylinder. That’s why following safety procedures is critical.
Frequently Asked Questions
How long does an MC cylinder last?
That depends on your flame setting and torch tip. For basic brazing, one full cylinder might last 30 to 45 minutes of active use.
Can I cut steel with it?
Yes—but only for small jobs. If you’re cutting thick steel or working for long periods, go for a larger B or E cylinder.
How do I know when it’s almost empty?
MC cylinders don’t have gauges. You’ll notice a drop in flame intensity. If you’re working in the field, it’s smart to carry a backup.
Final Thoughts
The acetylene MC size cylinder offers a great balance between size and performance for light-duty jobs. It’s portable, reliable, and widely supported by portable torch systems. Whether you’re doing HVAC work, small repairs, or artistic projects, it’s a tool worth keeping on hand—as long as you respect its limits and handle it safely.
