The clamp can open far enough and still have nowhere to sit

Hypothetical obstruction input · US scope · editorial review 2026-10-27

SHORT CAPTION
Enough clamp opening does not guarantee usable contact. This illustrative frame obstruction is a separate failed check from thickness.
https://desksizer.com/examples/#blocked-clamp-contact

LONG POST
Imagine a 25 mm desktop whose underside frame blocks the clamp’s bearing area. The top can fall inside the arm’s stated thickness range and still fail the contact check. This is a hypothetical obstruction example; the drawing is conceptual and does not assign a universal rail distance or clearance requirement.

Inspect the actual mounting position above and below the top. A drawer, rear rail, bevel or cable tray can prevent the supplied pads from sitting as the maker intends. Opening the clamp farther does not by itself solve an obstructed contact surface. Moving a tray or changing mounting method also needs the relevant instructions checked.

The linked preset records a blocked edge but leaves desktop permission unconfirmed. It does not invent a tested workaround, a spacer size or a drilling instruction. Use the exact clamp drawing, installation access and desktop guidance before choosing a different position. A source-linked thickness match and a failed contact check can appear in the same report without contradicting each other.

OPEN THE ILLUSTRATIVE INPUTS
https://desksizer.com/tools/monitor-arm-fit/?example=blocked-clamp-contact

GUIDE
https://desksizer.com/guides/monitor-arm-desk-clamp-fit/

SOURCES
Mount-It — https://www.mount-it.com/products/heavy-duty-single-monitor-arm (catalog review 2026-10-25)

LIMITS
Concept drawing only. No universal rail clearance is implied.
Not a customer testimonial, physical installation test, price promise or product endorsement.
No commission tracking is active in this material. Ordinary manufacturer sources and DeskSizer tool links only.

ILLUSTRATION
https://desksizer.com/share-cases/blocked-clamp-contact.png
