Welding Table editorial research · September 17, 2026 · Comparison method
Choosing between 16 mm and 28 mm starts with the work you need to hold. A larger bore gives access to a different fixture family; it does not automatically make the complete table more accurate, more stable or better suited to a small frame.
Compare a complete working setup, including the table structure, clamp reach, brackets and fasteners. The hole diameter is one specification within that setup.
Start with the part envelope
Sketch the largest assembly you expect to fixture and include the upright pieces. A flat plate, a small tube rectangle and a deep three-dimensional frame may occupy similar tabletop areas while demanding different clamp heights and support arrangements.
For compact work, bulky fixtures can consume space needed for the torch or measuring tools. For taller work, a small clamp may not reach the required contact point. Check actual dimensions rather than assigning all light work to one system and all heavy work to another.
Compare equivalent tooling, not just the table
A useful quote includes the hold-downs, locating stops, vertical brackets and connecting bolts needed for your first recurring job. Accessory quantities and geometry can change the total more than the headline table price.
BESSEY’s published range illustrates why model-level comparisons matter: its 16 mm and 28 mm clamps are offered with different capacities and throats. Their stated forces also come with test conditions. Those numbers are clamp specifications, not permission to impose the same load on every compatible tabletop.
The grid is a second decision
Siegmund documents a 100 × 100 mm grid for its System 28 range. Do not infer that pattern merely from a 28 mm label on another table. Likewise, a 16 mm bore does not establish the pitch of an unknown top.
Grid spacing affects where a fixed fixture can start; adjustable stops and brackets determine what positions you can reach between those locations. For a small repeated part, check whether the tooling can locate the part cleanly without crowding its joints.
Adapters need a defined job
A sleeve, spacer or adapter may be an approved part within a manufacturer’s system. It should name the table and the tool it connects. An improvised reduction from a 28 mm hole to a smaller pin does not, by itself, establish rigidity or correct bolt engagement.
Siegmund’s own compatibility information includes spacer-ring qualifications for some ranges. That is a useful reminder to check the entire assembly instead of assuming same-diameter products are interchangeable.
When changing systems is worth considering
Changing makes sense when the existing range cannot hold your actual jobs efficiently: insufficient reach, no suitable upright supports, or a table structure that does not meet the required use. A bigger hole alone is a weak reason to replace an otherwise useful fixture inventory.
Before committing, ask a supplier to demonstrate the layout for a representative part. Include access for loading, tightening, measuring and removing the finished assembly. A setup that fits on paper can still be awkward if the last clamp blocks the only removal path.
Choose the fixture family that handles your parts with clear access and documented compatibility, then compare the complete setup cost.
Questions & answers
Is a 28 mm welding table always stronger?
No. Table construction, supported load conditions and the exact fixtures determine suitability. Bore diameter alone is not a structural rating.
Can 16 mm tools be used on a 28 mm table?
Only where a documented compatible adapter or arrangement supports the exact parts. Do not infer approval from the ability to insert a smaller post.