Precision Granite Mounting Plate with Machined Air Bearing Bore

Can the bore diameter and bolt pattern be customized? Yes. This plate can be machined to match an existing drawing or reverse-engineered from a sample part. Bore diameter, hole spacing, thread type, and overall plate thickness are all adjustable.

How does granite compare to cast iron for this kind of mounting plate? Granite offers better long-term dimensional stability and vibration damping, with no magnetic interference — a meaningful advantage for air bearing and optical mounting applications, though granite plates are typically heavier and less impact-resistant than cast iron, so mounting orientation should account for that.

What's the lead time for a custom plate like this? Lead time depends on bore tolerance, flatness requirement, and order volume. Standard bolt patterns ship faster than fully custom hole layouts — send your drawing for an accurate timeline.

Do you provide calibration documentation with the finished part? Yes. Flatness and bore dimensions are verified using calibrated instruments traceable to national metrology institutes, and documentation can be provided on request.

Is marble ever used instead of granite for parts like this? Not by ZHHIMG. Some lower-cost suppliers substitute marble, which is less dense and less dimensionally stable over time. We use true black granite specifically because this kind of mounting application can't tolerate that trade-off.