Arron
15th July 2004, 02:02 PM
This is a set of matching gauges - pin, pencil and knife below, and a beam gauge (??) above.
After seeing MajorPanic's beautiful marking gauges on this site, it takes a little courage to put up my own efforts. I think it is worth it though because there is a couple of good ideas here which I have pinched.
I have wanted to make a set of gauges for a long time but have not been happy with the available methods of locking, and have baulked at the idea of cutting tiny, precise mortises for the knife point. The locking method used here consists of a dowel with two cutaway sections. One section is cut away square such that if it is lined up with the beam then the head can be removed completely. The other section is adjacent and has a slope, such that it acts like a wedge. The dowel will thus not fall out because it is of full thickness on either side of the cutaway sections and is held in place by the beam. Also, the beam and head will not separate unless the square cutaway section is lined up precisely with the mortise, something unlikely to occur by accident. Locking requires simply moving the dowel left with a thumb, and requires no readjustment of the hand. To unlock, move the dowel right, or tap it on a table if it is firm. I think this method is better then a conventional wedge that can be lost, and better then a screw in a wooden thread which usually requires a (tiny) repositioning of the hand to do up.
The knife point in the knife gauge is simply a blade form one of those knife sets in a $2 shop. There is a 12mm hole drilled in the beam. Two sections of 12mm dowel are split lengthwise. As always, one piece will be slightly thicker then the other, so the knife blade is put between the two thicker sections and forced into the 12mm hole. Initially push the assembly in just far enough so that the correct angle can be found for the knife - it should be set to pull away very slightly from the head to counteract the tendancy of the workpiece's grain to steer the gauge. About 3 degrees from parallel seems best. Once you are happy with how it performs, push it home. To replace the blade, just punch the assembly out.
These are the first things I have made strictly with hand tools. Not something I intend to do very often, but very worthwhile because it is a great skill builder. The timber is Euro oak.
Arron
After seeing MajorPanic's beautiful marking gauges on this site, it takes a little courage to put up my own efforts. I think it is worth it though because there is a couple of good ideas here which I have pinched.
I have wanted to make a set of gauges for a long time but have not been happy with the available methods of locking, and have baulked at the idea of cutting tiny, precise mortises for the knife point. The locking method used here consists of a dowel with two cutaway sections. One section is cut away square such that if it is lined up with the beam then the head can be removed completely. The other section is adjacent and has a slope, such that it acts like a wedge. The dowel will thus not fall out because it is of full thickness on either side of the cutaway sections and is held in place by the beam. Also, the beam and head will not separate unless the square cutaway section is lined up precisely with the mortise, something unlikely to occur by accident. Locking requires simply moving the dowel left with a thumb, and requires no readjustment of the hand. To unlock, move the dowel right, or tap it on a table if it is firm. I think this method is better then a conventional wedge that can be lost, and better then a screw in a wooden thread which usually requires a (tiny) repositioning of the hand to do up.
The knife point in the knife gauge is simply a blade form one of those knife sets in a $2 shop. There is a 12mm hole drilled in the beam. Two sections of 12mm dowel are split lengthwise. As always, one piece will be slightly thicker then the other, so the knife blade is put between the two thicker sections and forced into the 12mm hole. Initially push the assembly in just far enough so that the correct angle can be found for the knife - it should be set to pull away very slightly from the head to counteract the tendancy of the workpiece's grain to steer the gauge. About 3 degrees from parallel seems best. Once you are happy with how it performs, push it home. To replace the blade, just punch the assembly out.
These are the first things I have made strictly with hand tools. Not something I intend to do very often, but very worthwhile because it is a great skill builder. The timber is Euro oak.
Arron