How to Measure an Arcade Cabinet Cam Lock Before Ordering

The new lock fits through the door, but the cam stops short of the frame. Or the key turns only when you push hard against the panel. Both problems can come from choosing a lock by barrel length alone.

A cam lock is a small assembly with several dimensions working together. You need the lock body to fit the panel and the cam to reach the keeper in the correct position. Check both before ordering.

Start with the door open

Use the proper key to open the service door, then disconnect machine power before working inside the cabinet. Photograph the lock and cam in their locked and unlocked positions while the door is open. Record the orientation of washers, spacers and any bent cam.

Do not remove your only working lock until you have a way to keep the cabinet safely out of service. If you cannot open the lock normally, contact the owner or an appropriate locksmith rather than forcing the door.

Measure the body and mounting

Record the panel thickness at the actual mounting point, including any reinforcement plate. Then compare the lock's body or barrel dimension with the replacement supplier's drawing. Different listings may use different reference points, so "17 mm" should be tied to a specific dimension rather than assumed to mean the whole assembly.

Measure the mounting opening and note any flats or locating shape that prevents rotation. Check the clearance for the retaining nut and for nearby wiring. A longer body does not automatically solve a fit problem: it can create interference behind the panel.

Measure where the cam needs to land

With the door open, identify the part of the frame the cam engages. Record the reach from the lock's centreline to the engagement point, plus the required offset behind the door. Compare the existing cam's length, thickness, mounting shape and any bend.

Body length and cam reach are different measurements. Camlock Systems' cam specification guide describes cams as separate components with their own dimensions. A replacement body of the correct length may still need a different compatible cam.

Check rotation and key removal

Record which way the key turns and where the cam sits at each end of travel. Check whether the key can be removed in one position or more than one. These features affect how staff operate the door and whether the chosen cam reaches the keeper.

If several cabinets share keys, ask specifically about the available keying arrangement. Two locks supplied with similar-looking tubular keys are not necessarily keyed alike. Do not assume that a spare key for one will operate the other.

Use a short ordering checklist

• Panel thickness and mounting-hole shape.
• Body length, measured using the supplier's reference points.
• Cam length, offset and attachment shape.
• Required rotation and locked orientation.
• Key-removal behaviour and keying requirements.
• Space behind the panel for the full assembly.

Amuseparts offers tubular cam locks listed in 17 mm, 23 mm and 28 mm lengths. Compare the complete installation requirements before choosing the length.

Test with the door open before closing it

After fitting the correct lock, operate it several times with the door open. Confirm free movement and secure fixings. Then close the door gently and check engagement without forcing the key. If it binds, reopen the door and resolve the alignment. Using the key as a lever to pull a misaligned door shut can damage an otherwise suitable lock.

Keep the lock specification with the cabinet record. The next order can then be made from measurements rather than a hurried comparison through the service-door opening.