Round size reference
1-1/4" OD × .065" wall A513 round tubing
Theoretical dimensions and weights for 1-1/4" OD × .065" wall ASTM A513 round mechanical tubing, computed with the site's calculator formulas. Planning numbers, not acceptance criteria.
This page is a dimensional reference for 1-1/4" OD (1.250", or 1.250 in decimal) × .065" wall ASTM A513 round mechanical tubing. Every derived value — inside diameter, cross-sectional area, and weight — is theoretical, computed from the nominal dimensions with the same formulas as the tube weight calculator.
A size alone is not an order. The A513 manufacturing type governs the production route, and the purchased standard governs tolerances and acceptance — this page states neither. Use the specification builder to turn this size into a complete ordering description.
On this page
Tube weight calculator
Round: area = π/4 × (OD² − ID²), ID = OD − 2 × wall. Square and rectangular use outer minus inner rectangles, which slightly overstates weight by ignoring corner radii. Steel density 0.2836 lb/in³ (7,850 kg/m³). Real weight varies with corners, weld upset, scale, coating, and dimensional tolerance — never accept or reject material on calculated weight alone.
Dimensions at a glance
For 1-1/4" OD × .065" wall round tubing, the theoretical inside diameter is ID = OD − 2 × wall = 1.250 − 2 × 0.065 = 1.120 in. The wall-to-OD ratio is 5.2% (wall ÷ OD), a quick indicator of how thin-walled the section is relative to its diameter.
| Characteristic | Value | Basis |
|---|---|---|
| Outside diameter (OD) | 1-1/4" (1.250 in) | Nominal, as specified |
| Wall thickness | .065" (0.065 in) | Nominal, as specified |
| Inside diameter (ID) | 1.120 in | ID = OD − 2 × wall |
| Cross-sectional area | 0.2420 in² | π/4 × (OD² − ID²) |
| Theoretical weight | 0.824 lb/ft | Area × 12 × 0.2836 lb/in³ |
| Wall-to-OD ratio | 5.2% | Wall ÷ OD |
Theoretical piece weights at example lengths
The table below multiplies the theoretical 0.824 lb/ft figure by example piece lengths. These lengths illustrate the arithmetic only — they are not stock lengths, mill lengths, or a statement of what any producer supplies. Confirm length and length tolerance on the purchase order.
| Example piece length | Theoretical weight |
|---|---|
| 1 ft | 0.82 lb |
| 5 ft | 4.12 lb |
| 10 ft | 8.24 lb |
| 20 ft | 16.47 lb |
| 24 ft | 19.76 lb |
Other seeded 1-1/4" OD wall options
Within this size reference, the same 1-1/4" outside diameter is also seeded at the wall thicknesses below. A lighter wall lowers theoretical weight and enlarges the ID; a heavier wall does the opposite. Which wall is correct depends on the part — machining stock, fit, and forming behavior — not on weight alone.
| Size | Wall | ID (in) | Weight (lb/ft) | vs this page |
|---|---|---|---|---|
| 1-1/4" OD × .083" wall | .083" | 1.084 | 1.036 | Heavier wall · 0.212 lb/ft |
| 1-1/4" OD × .120" wall | .120" | 1.010 | 1.450 | Heavier wall · 0.626 lb/ft |
Ordering checklist for this size
Dimensions are only one line of a complete A513 order. Specify each item below explicitly and confirm it against the purchased current edition of ASTM A513/A513M and your supplier's quotation — this page states no normative requirement.
- A513 manufacturing type (1a, 1b, 2, 3, 4, 5, or 6) — stated as a type designation, not a trade nickname
- Grade or chemistry designation, per the drawing and the purchased standard
- Condition (for example as-welded, as-drawn, or a specified thermal treatment)
- Length, length tolerance basis, and quantity
- Dimensional tolerances: identify which of OD, ID, and wall govern and which float, per the purchased standard
- Testing requirements, including any nondestructive examination the application needs
- Certification level (for example a material test report), stated on the order rather than assumed
The tolerances guide explains how to identify the governing characteristics without copying uncontrolled tolerance tables, and the material properties guide explains why no generic strength value applies to A513. The specification builder assembles all of the above into a reviewable ordering description.
Frequently asked questions
What is the inside diameter of 1-1/4" OD × .065" wall A513 round tubing?
The theoretical inside diameter is 1.120 in, from ID = OD − 2 × wall (1.250 − 2 × 0.065). Actual ID varies within the ordered tolerances, so confirm the governing dimensions on the purchase order.
How much does a 20 ft piece of 1-1/4" OD × .065" wall A513 tubing weigh?
Theoretically 16.47 lb, from 0.824 lb/ft × 20 ft. This is a planning number computed from nominal dimensions, not an acceptance criterion.
Is theoretical weight an acceptance criterion for 1-1/4" OD × .065" wall tubing?
No. A513 product is ordered to dimensions, and dimensional tolerances mean actual weight varies piece to piece. Use theoretical weight for freight, handling, and rough cost planning only — never to accept or reject material.
What information belongs on an order for 1-1/4" OD × .065" wall A513 tubing besides the size?
The A513 manufacturing type, grade or chemistry, condition, length and quantity, the governing dimensional tolerances, testing, and certification — each stated explicitly and confirmed against the purchased current edition of ASTM A513/A513M.