Derek Cohen
02-22-2015, 11:57 AM
Introduction
As one of the few handtool-orientated woodworkers in my local woodwork club, I have been asked to present a regular lecture at meetings on handtools. This will be hands-on, for example, using tools to create joints. This coming month I plan to present a demonstration on mortice-and-tenon joinery.
It occurred to me that the only mortice gauges I own are Japanese, not Western types. I have two, one being a Kinshiro (thanks Wiley), which is the very best mortice/cutting gauge, in my opinion. It is not simply that they are so well made and have amazing knives that leave a clean line, but they are ergonomically so well designed, and fit the hand like a glove. I also like that the Adjuster Screw is situated so that they may be tightened with one hand.
I have built a number of single cutter gauges based on the Kinshiro, which are excellent for dovetails, or may be used in pairs for mortice-and tenons. The wide fence provides a lot of extra stability.
Original Kinshiro on the right ...
http://www.inthewoodshop.com/ShopMadeTools/KinshiroOnTheCheap_html_m6481cde7.jpg
One should mark mortices and tenons from the same gauge, working from a reference face. In this regard, the single flaw of the Kinshiro is that that are not suited for marking mortices that are set back from the edge of a stretcher ..
http://www.inthewoodshop.com/Furniture/AShakerTableforMothersDay_html_m169f15a9.jpg
The advantage of the traditional Western mortice gauge is that one adjusts the pins to the width of the mortice chisel, and then the fence may be adjusted in-and-out as necessary.
http://www.woodworkersjournal.com/wp-content/uploads/skill-builder-3.jpg
My thoughts went along the path of a fixed gauge, that is, one that was set up for a specific mortice chisel size. Indeed, why not make two, or more ..?
I also recalled I had a rarely used set of Tite-Mark wheel cutters for a mortice gauge. Perhaps these could be pressed into service? At the same time, while I like and have a number of wheel gauges, I found that these wheels required more downforce than a knife. Perhaps a heavier gauge than the Tite-Mark ...?
In the end I built two different mortice/cutting gauges. The first one looks traditional but has a few novel features, one of which I have not seen elsewhere. The second looks novel, but is more traditional.
Gauge #1
The first gauge is based on the Kinshiro profile, but has a Western arm. It is made from some scrap Fiddleback Jarrah and brass. The fence is 4 1/2" long x 2" high ...
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/1_zpsgyw8ijei.jpg
The novel feature here is that the blade is a fixed width, but is exchangeable for other fixed width blades ..
The knives are made from 4mm thick HSS (they should not need resharpening for a while!). So far I have made double-sided knives for a 1/4" and 3/8" mortice-and-tenons, and two straight knives (I made a second when I realised that the first would score 3/8" away from the fence). The idea for these knives came from dovetail planes.
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/2_zpsgjqxxike.jpg
The knives sit in a brass "cassette". This is fitted permanently in the arm ...
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/3_zpsxmoxavcf.jpg
As seen in the first image, each knife may be dropped in or out and is held with a set screw. As mentioned earlier, I have not seen a similar system on a marking gauge before.
The second design feature is a rounded lower section to the arm ..
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/4_zpskrn4d754.jpg
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/5_zps9blnvhlk.jpg
The reason for this is twofold:
Firstly, this is a very strong design that locks the arm very securely. Just a little downforce and there is no sideways movement at all.
Secondly, the rounded lower section offers better visibility that either a square section or a cutaway at the knife.
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/5a_zpsayx23ssh.jpg
In practice, this is very comfortable to use, and the knives cut clean lines both with and across the grain.
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/6_zpszemgwq34.jpg
As one of the few handtool-orientated woodworkers in my local woodwork club, I have been asked to present a regular lecture at meetings on handtools. This will be hands-on, for example, using tools to create joints. This coming month I plan to present a demonstration on mortice-and-tenon joinery.
It occurred to me that the only mortice gauges I own are Japanese, not Western types. I have two, one being a Kinshiro (thanks Wiley), which is the very best mortice/cutting gauge, in my opinion. It is not simply that they are so well made and have amazing knives that leave a clean line, but they are ergonomically so well designed, and fit the hand like a glove. I also like that the Adjuster Screw is situated so that they may be tightened with one hand.
I have built a number of single cutter gauges based on the Kinshiro, which are excellent for dovetails, or may be used in pairs for mortice-and tenons. The wide fence provides a lot of extra stability.
Original Kinshiro on the right ...
http://www.inthewoodshop.com/ShopMadeTools/KinshiroOnTheCheap_html_m6481cde7.jpg
One should mark mortices and tenons from the same gauge, working from a reference face. In this regard, the single flaw of the Kinshiro is that that are not suited for marking mortices that are set back from the edge of a stretcher ..
http://www.inthewoodshop.com/Furniture/AShakerTableforMothersDay_html_m169f15a9.jpg
The advantage of the traditional Western mortice gauge is that one adjusts the pins to the width of the mortice chisel, and then the fence may be adjusted in-and-out as necessary.
http://www.woodworkersjournal.com/wp-content/uploads/skill-builder-3.jpg
My thoughts went along the path of a fixed gauge, that is, one that was set up for a specific mortice chisel size. Indeed, why not make two, or more ..?
I also recalled I had a rarely used set of Tite-Mark wheel cutters for a mortice gauge. Perhaps these could be pressed into service? At the same time, while I like and have a number of wheel gauges, I found that these wheels required more downforce than a knife. Perhaps a heavier gauge than the Tite-Mark ...?
In the end I built two different mortice/cutting gauges. The first one looks traditional but has a few novel features, one of which I have not seen elsewhere. The second looks novel, but is more traditional.
Gauge #1
The first gauge is based on the Kinshiro profile, but has a Western arm. It is made from some scrap Fiddleback Jarrah and brass. The fence is 4 1/2" long x 2" high ...
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/1_zpsgyw8ijei.jpg
The novel feature here is that the blade is a fixed width, but is exchangeable for other fixed width blades ..
The knives are made from 4mm thick HSS (they should not need resharpening for a while!). So far I have made double-sided knives for a 1/4" and 3/8" mortice-and-tenons, and two straight knives (I made a second when I realised that the first would score 3/8" away from the fence). The idea for these knives came from dovetail planes.
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/2_zpsgjqxxike.jpg
The knives sit in a brass "cassette". This is fitted permanently in the arm ...
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/3_zpsxmoxavcf.jpg
As seen in the first image, each knife may be dropped in or out and is held with a set screw. As mentioned earlier, I have not seen a similar system on a marking gauge before.
The second design feature is a rounded lower section to the arm ..
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/4_zpskrn4d754.jpg
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/5_zps9blnvhlk.jpg
The reason for this is twofold:
Firstly, this is a very strong design that locks the arm very securely. Just a little downforce and there is no sideways movement at all.
Secondly, the rounded lower section offers better visibility that either a square section or a cutaway at the knife.
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/5a_zpsayx23ssh.jpg
In practice, this is very comfortable to use, and the knives cut clean lines both with and across the grain.
http://i13.photobucket.com/albums/a262/Derek50/Marking%20and%20Measuring/Two%20New%20Mortice%20and%20Cutting%20Gauges/6_zpszemgwq34.jpg