george wilson
03-27-2009, 5:17 PM
I was asked to copy an 1802 surveyor's compass for David Brinkley. The original was by Chandlee in Winchester,Va.. The original is in collections at Wmsbg.
This surveyor's compass was made from 1/4" 260 brass sheet,for the body.The sights and the large ring were cast as rough forms from 260 brass,basicaly blocks for the sights,and an oversize ring for the 6" ring. I did not have time to make patterns due to time constraints. The project took over 4 months to complete as it was.Much of the work was hand work,except for making the 360 degree graduations for the compass needle.
This was a gift from Colonial Williamsburg to thank the well known newsman for staying on as head of the Raleigh Tavern Society for another year. this is a large fund raising group in Col.Williamsburg.
The body was sawn out of sheet,and the edges were hand filed to the half round edge. The ring was turned on a lathe,and the decorative mouldings were turned with freehand held tools,just as the original was made.
The sights were finished and beveled at their bases by hand filing.The very narrow sighting slits were sawn with a jeweler's saw.
I made the glass level vials by melting one end of glass tubing shut,and bending a slight crown in them. The vials were usually filled,and putty was used to seal it in. I did not want mine to eventually leak dry like the old ones can do,so I pulled the other end of the tubing into a small neck,filled the tubes,and melted the glass shut,permanently sealing it forever.The thin brass covers were long enough to conceal the necked glass.
The engraving of the compass rose was hand done,and filled with black mastic as was the original.The compass face and graduated ring are silver plated.
The compass needle was made from hardened tool steel,and magnetized. These old compass needles had to be periodically renewed by stroking with a lodestone.There is seen a thin brass leaf projecting from the edge of the ring. This is cranked up by a screw from underneath the body plate against the needle when the compass is being carried about,to prevent the needle from being banged about,and losing its magnetism.
The little open port seen in the dial has a counter with numbers that can be swung into place from an adjustment handle under the body.
The sights are shown mounted for the picture,but there are brackets to hold them stored flat in the box. The lining of the box is hand woven broadcloth,similar to pool table cloth.It is too dark to see the details of the interior box,where the sights are stored.
You can see the wooden arms with brass handles that swing over the compass's arms to hold it in place.
The sterling silver plate is a dedication to David Brinkley.
The compass is about 14" long. I can't recall,as it was made in 1986. It is lacquered by brush in a transparent gold toned lacquer,as was common in the period,so the brass would not tarnish.
I spent 9 days hand polishing the compass. Buffing would have dragged the engraved note pad that is seen on the left arm of the body.
This compass is actually nicer than the original,as the old one had a "working" finish,while this one has a presentation finish.
David Brinkley collected scientific instruments. I suppose the powers that be decided that this would be appropriate for him to "show the way" in fund raising.
The box is walnut,with boxwood escutcheon. You can see the splines at all corners.
Unfortunately,I only have this one photograph of the compass,due to the rush to get it made in time for presentation.
I hope this compass is not getting too off topic for the woodworking forum,but at least,there is some woodworking,and it is still a tool.Each and every part of this piece was custom made for it except the box hinges and the lock. I usually made the locks too,but time was running out. This is my first try at scanning pictures.
This surveyor's compass was made from 1/4" 260 brass sheet,for the body.The sights and the large ring were cast as rough forms from 260 brass,basicaly blocks for the sights,and an oversize ring for the 6" ring. I did not have time to make patterns due to time constraints. The project took over 4 months to complete as it was.Much of the work was hand work,except for making the 360 degree graduations for the compass needle.
This was a gift from Colonial Williamsburg to thank the well known newsman for staying on as head of the Raleigh Tavern Society for another year. this is a large fund raising group in Col.Williamsburg.
The body was sawn out of sheet,and the edges were hand filed to the half round edge. The ring was turned on a lathe,and the decorative mouldings were turned with freehand held tools,just as the original was made.
The sights were finished and beveled at their bases by hand filing.The very narrow sighting slits were sawn with a jeweler's saw.
I made the glass level vials by melting one end of glass tubing shut,and bending a slight crown in them. The vials were usually filled,and putty was used to seal it in. I did not want mine to eventually leak dry like the old ones can do,so I pulled the other end of the tubing into a small neck,filled the tubes,and melted the glass shut,permanently sealing it forever.The thin brass covers were long enough to conceal the necked glass.
The engraving of the compass rose was hand done,and filled with black mastic as was the original.The compass face and graduated ring are silver plated.
The compass needle was made from hardened tool steel,and magnetized. These old compass needles had to be periodically renewed by stroking with a lodestone.There is seen a thin brass leaf projecting from the edge of the ring. This is cranked up by a screw from underneath the body plate against the needle when the compass is being carried about,to prevent the needle from being banged about,and losing its magnetism.
The little open port seen in the dial has a counter with numbers that can be swung into place from an adjustment handle under the body.
The sights are shown mounted for the picture,but there are brackets to hold them stored flat in the box. The lining of the box is hand woven broadcloth,similar to pool table cloth.It is too dark to see the details of the interior box,where the sights are stored.
You can see the wooden arms with brass handles that swing over the compass's arms to hold it in place.
The sterling silver plate is a dedication to David Brinkley.
The compass is about 14" long. I can't recall,as it was made in 1986. It is lacquered by brush in a transparent gold toned lacquer,as was common in the period,so the brass would not tarnish.
I spent 9 days hand polishing the compass. Buffing would have dragged the engraved note pad that is seen on the left arm of the body.
This compass is actually nicer than the original,as the old one had a "working" finish,while this one has a presentation finish.
David Brinkley collected scientific instruments. I suppose the powers that be decided that this would be appropriate for him to "show the way" in fund raising.
The box is walnut,with boxwood escutcheon. You can see the splines at all corners.
Unfortunately,I only have this one photograph of the compass,due to the rush to get it made in time for presentation.
I hope this compass is not getting too off topic for the woodworking forum,but at least,there is some woodworking,and it is still a tool.Each and every part of this piece was custom made for it except the box hinges and the lock. I usually made the locks too,but time was running out. This is my first try at scanning pictures.