Knob for Mortice Gauge

[Bassbear81]

Picked up a Marples mortice gauge from the boot sale they weekend, but its got a screw in the lock, does anyone know where I can get a knurled on from (or is it suposed to have a screw).

Whats the best way of cleaning the it up.

 

[GazPal]

Some use a simple slot headed grub screw and others a knurl headed screw. It depends on which model it is. Both fixing methods have their own pro's and con's, but there's no guarantee you'll find matching threads if you decide to switch one fixing screw type for the other.

 

[Alf]

Very likely it's supposed to have a screw; easy adjustability of gauges wasn't necessarily desirable if you wanted to retain the setting for later in the project. Cleaning it up depends on the condition really; fine wire wool or non-woven abrasive pad and white spirit is usually a fairly safe bet to start. A pic would be helpful in tailoring the advice to suit the tool - but mainly it'd be helpful because I'm nosy. :wink:

 

[Bassbear81]

Here is a pic

 

[Harbo]

Definitely an original screw which can be turned with a coin ( and a wide screwdriver).

Rod

 

[bugbear]

Definitely an original screw which can be turned with a coin ( and a wide screwdriver).

Rod

Agreed. It appears that mortice gauges were left set for a good while.

The most fancy gauges of all, the famous "Ultimatums" were also locked by a screw, not a knob.

BugBear

 

[GazPal]

For repetitive shop and site work - where consistancy in marking out for locks and joints is more desirable - we'd tend to prefer the slot headed grub screw for locking down settings on mortise, marking and cutting gauges, but the knurled nut/button headed screw for speedier adjustments if having to shift between settings in quick succession.

The grub screw takes a little longer to loosen and re-tighten and tends to be less prone to accidental damage than the knurl headed screw variety, but both serve precisely the same function.