Rough Beveling
A hand made fly rod is a relative concept. Strictly speaking 'hand made' means no power--none at all. By that definition, my rods are not hand made. For example, I use a lathe to form cork grips; I use a drill press for drilling ferrule holes for pinning.
But the most conspicuous use of power that I employ is that of a powered milling machine. The milling machine I use is called a Medved beveler. I never met Mr. Medved, but my implementation of his design is more than adequate to the task of rough beveling split cane strips into rod splines.
While it's true that rough beveling can be accomplished by hand, this is one step that I am happy to break with tradition (if you can even call it that) and go with power. There's a contiuum of belief here. Some believe that the 'best' way to make a fly rod is by hand--especially in this case. Of course, this ignores the fact that many of the old dead guys used power in the beveling and tapering processes. The point is arguable and I won't belabor it further here.
I won't go into detail about the construction of the beveling tool here. Highly detailed plans for the design can be found in books like Jack Howell's The Lovely Reed or elsewhere on the Web. The process for me was to build an interpretation of the design with the materials I had and tweak it to meet my needs. As I go along in the section I'll capture what I think are the important properties of the tool.
Before I proceed with describing the details of rough beveling, I should define the process itself. Rough beveling transforms split strips of bamboo into consistently beveled splines which are prepared for tapering in a planing form. We start by putting a 90 degree bevel on all the strips. That is, we mill the work such that its cross section is square. This is important because when we switch to the sixty degree jig, we'll have a conistent stock to work with.
Begin by sorting the strips by width. If you followed the process in the previous section, most of the strips should be of the thinner variety--for tips.
Set those aside for now. We'll bevel the butt strips first. There's not as much material to remove. Attach the 90 degree jig to the back plate.
Set the tensioners to apply light pressure to the strips that lay in the grove.
Lay a strip in the jig. Push it past the first tensioner. Turn the router bit so that one of the cutting surfaces is at the very bottom of travel. Line up the jig so that the top of the strip is about one millimeter above the blade travel. In other words, one the machine is powered up, passing the work past the bit will remove one millimeter of material. Be careful here. Removing too much material will destroy the work.
Anchor the jig tightly to the backplate (i use wing nuts that I snug up with a crescent wrench). Hand tighten the set screw also. The set screw is important, not because it it helps hold the jig in place, but rather by its use as a reference point when making small adjustments to the jig. We'll see later in this section that, for each round of milling, we'll move the jig slightly up so that more material is removed with each pass of the work.
Power up the router. Wearing gloves, grasp the strip with both hands and pass it into the jig (as you can see, on my jig, the motion is from left to right). Never mill the enamel side. Lay the strip in the jig enamel-side down.
As the strip passes the end of the jig on the right side, grasp the strip with your right hand. As enough of the strip is pulled out of the jig, grasp it with both hands and change from a pushing to a pulling motion. The trick here is to not stop moving the strip at any time during the pass. If you stop, the bit will burn the work. As the left end of the strip approaches the bit, lift your hands so that the strip angles up off the jig slightly. This avoids the problem of end shredding by the router bit. Basically, what happens is that the cutting surface of the bit will catch the end edge of the strip and fray it. It's kind of like putting a popsicle stick in a blender.
Two more passes are required for this strip. Lay the strip in the jig so with the enamel side facing you. Pass the strip again with the enamel facing away from you. What you end up with is a strip that is milled on three sides.
Repeat this for each butt strip. Reset the jig to remove another millimeter or two. Here's where the set screw comes in handy. I know that four half-turns of my set screw is the proper distance of travel for each round--your results may vary. How do you know ultimately how much material to remove? Two things determine this. First, you want to remove enough material from the work to render sharp edges all the way down the strip on all sides.
Second, you want the thickness of the square-beveled strips to be about 200% of the final thickness of the beefiest part of the taper. I know I haven't covered tapers yet, but you shouldn't start this process without understanding what a taper is and what the end result should be.
Once the butt strips have been satifactorally milled, start over with the tips. The last jig-depth setting for the butt strips should be a good starting point for the tip strips. Repeat the process for the tip strips.
Switch jigs. Install the sixty degree jig. You'll also need to reset the set screw.
Repeat the tuning steps for the depth of cut. The difference here is that you'll be laying 90-degree strips in a 60-degree jig, so for the first few passes, the strips won't lay evenly in the jig. That's fine; just try to keep the enamel side of the strip laying flat on one of the jig edges. After the first pass, you'll end up with a strip with five sides: three at ninety degrees and two that seem to cut off the last angle. Continue restting the set screw and the jig and milling opposite edges with each pass.
Once the butt splines have been satisfactorally beveled, swtich over to the tips. The jig depth setting is always pretty close to the perfect starting depth for tips when I complete the butts.
I usually run four to six passes with the tips to get them down to size. Again, we're beveling to the dimensions of the thickest part of the taper on the spline. This will vary between a dainty little 3 weight and a chubby Paul Young parabolic taper.
There's a noticable difference between the tips and the butt when the beveling is done.
With each pass, you can feel the group of splines getting lighter and more coherent in the hand. What you end up with is so much smaller than what you start with. This process really removes plenty of material. At the end of a long saturday of beveling, there's always a nice mound of sawdust on the floor of my garage. It's nice physical evidence of a hard day's work.
But the most conspicuous use of power that I employ is that of a powered milling machine. The milling machine I use is called a Medved beveler. I never met Mr. Medved, but my implementation of his design is more than adequate to the task of rough beveling split cane strips into rod splines.
While it's true that rough beveling can be accomplished by hand, this is one step that I am happy to break with tradition (if you can even call it that) and go with power. There's a contiuum of belief here. Some believe that the 'best' way to make a fly rod is by hand--especially in this case. Of course, this ignores the fact that many of the old dead guys used power in the beveling and tapering processes. The point is arguable and I won't belabor it further here.
I won't go into detail about the construction of the beveling tool here. Highly detailed plans for the design can be found in books like Jack Howell's The Lovely Reed or elsewhere on the Web. The process for me was to build an interpretation of the design with the materials I had and tweak it to meet my needs. As I go along in the section I'll capture what I think are the important properties of the tool.
Before I proceed with describing the details of rough beveling, I should define the process itself. Rough beveling transforms split strips of bamboo into consistently beveled splines which are prepared for tapering in a planing form. We start by putting a 90 degree bevel on all the strips. That is, we mill the work such that its cross section is square. This is important because when we switch to the sixty degree jig, we'll have a conistent stock to work with.
Begin by sorting the strips by width. If you followed the process in the previous section, most of the strips should be of the thinner variety--for tips.
Set those aside for now. We'll bevel the butt strips first. There's not as much material to remove. Attach the 90 degree jig to the back plate.
Set the tensioners to apply light pressure to the strips that lay in the grove.
Lay a strip in the jig. Push it past the first tensioner. Turn the router bit so that one of the cutting surfaces is at the very bottom of travel. Line up the jig so that the top of the strip is about one millimeter above the blade travel. In other words, one the machine is powered up, passing the work past the bit will remove one millimeter of material. Be careful here. Removing too much material will destroy the work.
Anchor the jig tightly to the backplate (i use wing nuts that I snug up with a crescent wrench). Hand tighten the set screw also. The set screw is important, not because it it helps hold the jig in place, but rather by its use as a reference point when making small adjustments to the jig. We'll see later in this section that, for each round of milling, we'll move the jig slightly up so that more material is removed with each pass of the work.
Power up the router. Wearing gloves, grasp the strip with both hands and pass it into the jig (as you can see, on my jig, the motion is from left to right). Never mill the enamel side. Lay the strip in the jig enamel-side down.
As the strip passes the end of the jig on the right side, grasp the strip with your right hand. As enough of the strip is pulled out of the jig, grasp it with both hands and change from a pushing to a pulling motion. The trick here is to not stop moving the strip at any time during the pass. If you stop, the bit will burn the work. As the left end of the strip approaches the bit, lift your hands so that the strip angles up off the jig slightly. This avoids the problem of end shredding by the router bit. Basically, what happens is that the cutting surface of the bit will catch the end edge of the strip and fray it. It's kind of like putting a popsicle stick in a blender.
Two more passes are required for this strip. Lay the strip in the jig so with the enamel side facing you. Pass the strip again with the enamel facing away from you. What you end up with is a strip that is milled on three sides.
Repeat this for each butt strip. Reset the jig to remove another millimeter or two. Here's where the set screw comes in handy. I know that four half-turns of my set screw is the proper distance of travel for each round--your results may vary. How do you know ultimately how much material to remove? Two things determine this. First, you want to remove enough material from the work to render sharp edges all the way down the strip on all sides.
Second, you want the thickness of the square-beveled strips to be about 200% of the final thickness of the beefiest part of the taper. I know I haven't covered tapers yet, but you shouldn't start this process without understanding what a taper is and what the end result should be.
Once the butt strips have been satifactorally milled, start over with the tips. The last jig-depth setting for the butt strips should be a good starting point for the tip strips. Repeat the process for the tip strips.
Switch jigs. Install the sixty degree jig. You'll also need to reset the set screw.
Repeat the tuning steps for the depth of cut. The difference here is that you'll be laying 90-degree strips in a 60-degree jig, so for the first few passes, the strips won't lay evenly in the jig. That's fine; just try to keep the enamel side of the strip laying flat on one of the jig edges. After the first pass, you'll end up with a strip with five sides: three at ninety degrees and two that seem to cut off the last angle. Continue restting the set screw and the jig and milling opposite edges with each pass.
Once the butt splines have been satisfactorally beveled, swtich over to the tips. The jig depth setting is always pretty close to the perfect starting depth for tips when I complete the butts.
I usually run four to six passes with the tips to get them down to size. Again, we're beveling to the dimensions of the thickest part of the taper on the spline. This will vary between a dainty little 3 weight and a chubby Paul Young parabolic taper.
There's a noticable difference between the tips and the butt when the beveling is done.
With each pass, you can feel the group of splines getting lighter and more coherent in the hand. What you end up with is so much smaller than what you start with. This process really removes plenty of material. At the end of a long saturday of beveling, there's always a nice mound of sawdust on the floor of my garage. It's nice physical evidence of a hard day's work.
posted by Brooks Bollich | 10:09 AM
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