4130 Tubing — 0.049" Wall
0.049" wall, equal to 1.24 mm or 18 gauge, is a light structural wall. It is thick enough to weld comfortably and thin enough to keep a frame light, which makes it a favourite for aircraft, bicycle and light chassis work.
Where a 0.049" Wall Is Used
In aircraft structures it is used for longerons and highly loaded truss members, often at 3/4" to 1-1/8" OD. Bicycle and motorcycle builders use it for down tubes and rails. In race cars it appears in suspension links, body framing and bracing that sits outside the mandated safety structure.
Compared with 0.035", the extra 0.014" adds about 40 percent to the metal in the section at the same diameter, with a matching gain in dent resistance.
Fabrication Notes
This wall TIG welds readily with a small filler rod and bends well on mandrel or rotary draw equipment at moderate radii. It is below the minimum wall most motorsport rules set for cage tubes, so keep it out of the safety structure. Compare options in the wall thickness guide.
0.049" Wall 4130 Tubing: OD, Bore and Weight Table
The table shows how a 0.049" (1.24 mm) wall behaves across common outside diameters. The OD-to-wall ratio is a quick guide to how easily the tube bends and how readily it dents.
| OD (in) | OD (mm) | ID (in) | OD / wall ratio | Weight (lb/ft) | Weight (kg/m) |
|---|---|---|---|---|---|
| 0.375" | 9.52 | 0.277" | 7.7 | 0.17 | 0.25 |
| 0.500" | 12.70 | 0.402" | 10.2 | 0.24 | 0.35 |
| 0.625" | 15.88 | 0.527" | 12.8 | 0.30 | 0.45 |
| 0.750" | 19.05 | 0.652" | 15.3 | 0.37 | 0.55 |
| 0.875" | 22.22 | 0.777" | 17.9 | 0.43 | 0.64 |
| 1.000" | 25.40 | 0.902" | 20.4 | 0.50 | 0.74 |
| 1.125" | 28.57 | 1.027" | 23.0 | 0.56 | 0.84 |
| 1.250" | 31.75 | 1.152" | 25.5 | 0.63 | 0.94 |
| 1.375" | 34.92 | 1.277" | 28.1 | 0.69 | 1.03 |
| 1.500" | 38.10 | 1.402" | 30.6 | 0.76 | 1.13 |
| 1.625" | 41.27 | 1.527" | 33.2 | 0.83 | 1.23 |
| 1.750" | 44.45 | 1.652" | 35.7 | 0.89 | 1.33 |
| 2.000" | 50.80 | 1.902" | 40.8 | 1.02 | 1.52 |
| 2.500" | 63.50 | 2.402" | 51.0 | 1.28 | 1.91 |
Values are calculated from nominal dimensions (weight = (OD − wall) × wall × 10.69). A row in this table is a dimensional reference, not a statement that the size is held in stock; confirm availability when you enquire.
Frequently Asked Questions
What is 0.049" wall in millimetres and gauge?
0.049" equals 1.24 mm and corresponds to 18 gauge (BWG).
How much does 1.000" × 0.049" 4130 tubing weigh?
About 0.50 lb/ft, or 0.74 kg/m, from nominal dimensions.
Is 0.049" wall allowed in a roll cage?
Generally not for the cage itself. Rulebooks usually require heavier walls for roll structure members. It may be used for non-structural parts.
Is 0.049" wall easy to bend?
Yes at moderate radii with proper tooling. Large diameters in this wall need internal support.
Enquire for 4130 Tubing with 0.049" Wall
Specify your required OD, condition, standard, and footage to accompany the 0.049" wall requirement.
- Wall: 0.049"
- OD required
- Standard (ASTM A519)
- Condition
- Footage
- MTC 3.1
- Delivery