Notes on Tools

Introduction

Many old tools have brass parts, often set into wood to resist wear, or marked to show a measuring scale. These parts can become badly tarnished if stored in damp sheds, so need to be cleaned as part of the restoration of the whole tool.

However, most collectors agree that it is wrong to polish these parts so they look like a pub's display of horse brasses. Polishing with Brasso or similar

• would not have been done by the tool's original user;
• can obscure the pattern of wear (which gives clues about how the tool was used;) and
• can destroy markings and square edges.

This note illustrates some more cautious techniques.

Fig 1 – Neglected mortice gauge

Fig 2 – Another neglected mortice gauge

These are typical examples. Two brass and ebony mortice gauges and a beech brace with a brass chuck.

On all three tools the brass parts need to move freely for the tools to be usable.

Fig 3 – Neglected brace

Fig 4 – detail of brace chuck

Cleaning the gauges

Although dirty, the gauges were in good condition and came apart easily.

The first step was just to rub some of the dirt off with the old towel, used dry.

On this gauge I then used a very small amount of Maas brand polish (Maas metal polish cream) on a rag wrapped around my finger. This is a very gentle polish sold for cleaning gold, silver and other metals. If you go slowly and don’t press too hard you can remove just the top layer of dirt but leave the aged appearance. Fig 6 shows what I consider to be as far as I would go. You can see the blackening on the rag.

Fig 5 – gauge stem as found

Fig 6 – gauge stem after use of Maas polish

For hard to reach parts – such as around the pins – it was impractical to use rag so I just rubbed gently with a scrap of soft wood. This was enough to remove the surface dirt.

After cleaning I applied a thin coat of Renaissance brand microcrystalline wax to all parts of the gauge including the internal screw thread and sliding parts. This will protect it from handling and prevent future deterioration.

Fig 7 – soft wood to clean details

Fig 8 – brass cleaned

Fig 9 – only the right hand side has been cleaned

Fig 10 – slightly more dirt coming off

The finished state – clean enough but not over done.

The wax is also ideal as a lubricant on the moving parts. A toothbrush is good for getting the dirt off.

Fig 11 – gauge cleaned with Renaissance wax

Fig 12 – mechanism as found

Fig 13 – adjuster after minimal cleaning and lubrication with wax

Fig 14 – finished brace. The brass chuck still shows the pattern of use.