How to Size a 3D Welding Platform: Dimensions, Thickness and Load Guide

Most 3D welding platform orders are specified backwards: the buyer picks a familiar size, then discovers the fixture overhangs the edge or the plate deflects under the heaviest job. Sizing is a five-variable problem — part envelope, plate thickness, material, hole system and load rating — and getting the order right means working through them in sequence rather than by habit.

Step 1 — Start From the Part Envelope, Not the Catalogue

Take the largest workpiece diagonal, add clamp clearance on all sides, and add a working margin of at least 100 mm. Round up to the next standard grid multiple so clamps land on whole bore positions. Standard sizes include 1000×1000, 1200×1200, 1500×1000, 1500×1500, 2000×1000, 2400×1200 and 3000×1500 mm; any non-standard dimension can be produced to order.

Step 2 — Plate Thickness and Load Rating

Thickness is not just strength — it is thermal mass. A thicker plate absorbs welding heat with less local distortion and holds flatness longer under repeated thermal cycling.

Step 3 — Material: HT300 Cast Iron or Q355 Steel

• HT300 cast iron: excellent wear resistance, vibration damping and dimensional stability. The default choice where precision and stability matter, and where the table stays in one place.

• Q355 steel: high strength and toughness, withstands larger and more shock-prone loads, and is lighter and more repairable. Choose it for portable stations or very large single-piece tops.

Step 4 — Hole System: D28 or D16

D28 uses Ø28.065–Ø28.149 mm bores on a 100 ± 0.05 mm grid — the right choice for heavy structural work and rigid, high-force clamping (including robot cells). D16 uses Ø16.065–Ø16.149 mm bores on a 50 ± 0.05 mm grid for fine-pitch, small-part work. If you already own tooling in one system, match it and protect that investment.

Step 5 — Surface, Legs and Accessories

• Surface: full nitriding to HV 450–630 resists spatter burn-in and scoring.

• Flatness: 0.1 / 1000 mm; verticality 0.1 / 200 mm; roughness Ra 3.2.

• Working height: commonly 820–850 mm, custom heights available on request.

• Levelling: adjustable feet are essential — an unlevelled table is the fastest route to permanent deformation.

• Mobility: optional brake casters for flexible workshop layouts.

• Accessories: budget for a complete kit — clamps, locating pins, angle brackets, V-blocks and support blocks.

Common Specification Mistakes

• Sizing to the average part instead of the largest one.

• Under-specifying load, then adding a heavy fixture later.

• Ignoring levelling and floor condition.

• Ordering the plate but only a token accessory set.

• Failing to request a calibration report tied to CMM inspection.

FAQ