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1.           Riser design and layout 

The type of bow being built and its riser design will, in large part, determine the position of the bow joint.  Keep the joint as close as possible to the center of mass of the grip without intruding on the shelf area or lower riser fadeout with the tang of the male or female dovetails. This usually means the separation  in the bow will be roughly in line with the third  finger of your bow hand.

Using your template, trace the back outline of the grip on the riser block. Leave the belly straight to the tapers.  Be sure to include the shelf position in both side to side and back to belly views. Next, with the female half toward the bottom limb,  lay  the BevelLok Bow Joint along the side and back of the riser block and trace around it.            

  Inletting for joint tang and cutting riser

It is at this point that the back of the riser should be inlet for the joint tang. This can be done a variety of ways, but we found  the easiest is to use a handheld router and a 5/8” bit.  Make certain your router is unplugged !! 

Adjust the rail on your router base so that the bit is centered down the back of the riser. See Figure 5 

Now clamp the riser block in a vise, set the router depth  and carefully inlet for the joint tang.  Go a bit beyond the end lines to be certain that there will  be no interference later.

The next step is to determine the location and angle of the cut to separate the limbs. Reposition the female dovetail on the side of the riser and mark the upper corner at the back of the bow and the bottom of the opening at the belly.  A straight line through these two points establishes where the riser should be cut.  See Figure  6

Fig. 6

Using a power miter box or similar tool, position the riser, belly against the rail. Set the blade angle to match your line and cut the riser. 

  3.            Set-up and inletting for joint dovetail

This operation  requires the use of a jig to hold the two pieces of riser on location to ensure the inletting is done at precisely the right angle and to the correct depth.  The jig can be fabricated from scrap pieces of hardwood as pictured below.

Using a bevel square, measure the angle between the riser belly and the bottom of the female dovetail and transfer that angle to the jig.   See Figures 8 & 9

Because the angle in the upper limb is the exact opposite of that in the lower limb, no other adjustments need to be made to the jig. Clamp the upper riser section to the right side of the pivot arm. Set the router bit depth to the traced edge of the male dovetail. Now position the lower section of the riser on the other side of the pivot arm so that the router bit depth aligns with the traced edge of the female dovetail and clamp securely.  Figures  10 & 11

Next, secure the jig to the edge of a work bench or other true surface. Make sure the jig is flush with and at right angles to the edge. Insert the BevelLok tang in the back of the riser sections. Trace around the dovetail on the end grain as a reference during the routing operation. See Figure  12

Once the bit depth has been set, guiding the router around the traced lines is all that remains of the inletting process.  An easy method is to build a small right angle jig and clamp or otherwise fasten it to the bench. 

Determine the radius of your router base. In this example it is 3” (6” dia. divided by 2). Subtract the radius of your router bit. BevelLok corners have a 3/16” radius which calls for a 3/8” router bit. However, since the width of the dovetail opening is 7/8”, we use a 1/2” bit because it overlaps the center.  In Figure 13, the jig is positioned 2 3/4” from the innermost side and belly lines of the lower riser section.  These dimensions are given as examples only.  It is important that you take your own measurements !

Figure 13 also shows a 3/8” spacer inserted  between the right angle jig and the router base. This will position the 1/2” router bit to cut to the outermost edge of the dovetail opening. Once the outer pass has been made, remove the spacer and make a second pass to complete the inletting. Next, flip the right angle jig over and repeat the process to inlet the upper riser section.  It is a good idea to double check the dovetail fit while the riser sections are still in their jig.

This completes the inletting procedures.

Note:  It  is a very good idea to do all of the inletting in a piece of stock ½ the thickness of the material to be used in the bow.  This extra step will provide a cross-sectional view of the routed cavities to make certain inletting is to the proper depth and the wood to metal fit is precise.  It can also serve as a set-up template for future BevelLok installations.  

Many riser designs require the joint tangs to be bent to conform to the back curvature.  The joints are machined from 440 stainless steel and are malleable. Set the BevelLok on a piece of soft wood. Strike the tangs with a punch between the screw holes along the inside of the radius.

These photos show the cross-sectional riser pieces with the BevelLok tangs bent to fit and the whole assembly resting in the alignment jig.

4.             Alignment during joint installation 

The jig shown at right is useful to hold all of the pieces on location during the joint bedding. It is nothing more than a short length of straight wall 3” aluminum channel and anything similar will do.  

Remove the cross sectional pieces and reload the jig with your full size riser as follows:

1.   First, assemble all of the pieces dry and clamp the riser sections to the channel. Pinch two of the mycarta spacers together and use them as a feeler gauge to be sure they will fit in the gap later on.  

2.   Apply a small amount of epoxy to the inlet area of the lower limb and clamp it in the jig.

3.   Be sure the BevelLok is clean on the outside and the dovetails are securely locked together.

4.   Bed the female end of the joint in the epoxy and slide the dry upper riser section into the jig to capture the joint between it and the lower riser section and clamp it in place.

5.   Drive a narrow wedge between the aluminum channel and the BevelLok to bed the tang along the back.

6.   Now stand the jig at an angle to allow the epoxy to form a solid bed under the female dovetail.  Set the assembly aside overnight or until the epoxy has cured. In the morning, apply a similar amount of epoxy to the inlet area of upper riser section and invert the jig to form a similar bed under the male dovetail.

See Figure 16

This bedding technique eliminates any influence the grain in the wood may have on the joint positioning when mechanical fasteners are applied.

     5.                Installation of mechanical fasteners                              

  Remove the jointed riser from the jig, but Do Not attempt to separate the joint yet.! 

1.   First, reinforce the epoxy with screws or bolts.

2.   Using a hand drill and countersink, remove the excess epoxy from each of the six holes along the back of the riser. This will also reestablish the centers for drilling and tapping.

3.   Drill and tap for screws or drill all the way through and counter bore on the belly side of riser for washer and nut.

4.   Install and tighten the six mechanical fasteners that run back to belly.

5.   Support the lower portion of the riser belly along edge of cut and strike the upper portion as shown in figure #15 to separate the joint.

6.   Repeat steps 1-3 to install the end grain screws.

7.   Finally, remove each of the screws or bolts, coat with epoxy, and reinstall them.

         Dovetail fit 

The BeveLok Bow Joint is designed to have no clearance between the mating surfaces when assembled and to require a fair amount of effort to drive home or take apart. To get a feel for the amount of force needed, slide the dovetail together until it is snug. Hold the upper section so the belly edge of the cut is supported by the heel of one hand. With the heel of your other hand, thump the lower section sharply at the edge of the cut once or twice from back to belly. To loosen the joint, flip the riser over and strike the lower limb once or twice with similar force from belly to back. A bit more effort is required to overcome the static friction in the joint. Keep in mind the finished bows’ mass will add leverage and allow the limbs to come apart a bit easier than the riser alone.

  Once familiar with the joint fit, thump it securely together and lay the bow up just as you would a one piece.

 Note: To keep the lamination epoxy out of the joint, squeeze a bit of hot melt in the void around the metal tongue and groove at the back of the BevelLok.

The limbs can again be separated any time after the bow leaves the oven. To do so, simply use a hacksaw or emery wheel to cut through the laminations and overlays at back and belly parallel with the cut in the riser. Once again support the lower limb and strike the upper, this time with a block of wood, as shown in Figure 15.

  8.                   Installation of mycarta spacers     

The BevelLok Bow Joint and the mycarta spacers have a special relationship which set this take-down system apart. During bow construction the joints’ tapered surfaces serve as a vise to squeeze the spacers against the riser end grain. In the finished bow, those same tapers squeeze the mycarta surfaces tightly against each other and, because they are installed at an angle to the BevelLok, the spacers act as a stop to keep the limbs perfectly aligned, back to belly.  Properly fitted, the metal joint surfaces should mate just ahead of the mycarta surfaces. Timing is critical, but easy to achieve.

1.   Dress off the ends of all laminations and overlays evenly with the riser ends. As you shape the bow, leave the riser somewhat square-sided around the joint.

2.   Using a dental pick or similar tool, clean out the hot melt and any epoxy which may have gotten in around the tongue and groove of the BevelLok.

3.   Using the same technique as you did earlier with just the riser, take the bow apart and put it together several times. Next, thump the limbs firmly together and draw a thin line perpendicular to the gap on the side of the riser. This is a timing reference.

4.   Take the bow apart and fit the mycarta spacers around the joint.

5.   Reassemble the bow with the dry spacers in place and realign your timing mark. The mycarta should fill the gap within about .005”.

6.   Making certain the timing mark is aligned, dress the riser and mycarta flush at the back and belly of the bow.

7.   Separate the limbs, apply a thin coat of epoxy to the end grain of each, and set the spacers in place around the joint.

8.   Apply a thin coat of wax or other light grease as a release agent between the mating mycarta surfaces and reassemble the bow.

9.   Thump the back of the lower limb with a rubber mallet to again align the timing mark. Check to be sure the back and belly surfaces are flush across the joint.

10.Once the epoxy has cured, bump the limbs apart, clean away the grease or wax around the joint and finish the bow as you normally would. 

  Congratulations!!

You have created a take-down traditional bow which will give you a lifetime of quiet and dependable service. Enjoy.

WARRANTY

All BevelLok Bow Joint hardware is warranted against defects in material and workmanship for life.  Said defects do not include scratches or dings caused by normal use or wear.  Buyer agrees the sole and exclusive warranty recourse on any Sppets International product shall be repair or replacement of the defective part or parts. 

There are no other warranties, expressed or implied, that extend beyond those written here.  No agent, employee or representative of Sppets International or its dealers has the authority to bind Sppets International to any agreement not herein stated.   Further, Sppets International shall not be liable for any injury or collateral damage. The user assumes all safety and liability risks.

  For warranty service, return product, postage paid to:

                               Sppets International                 247 Libby Road                P.O. Box 860                 South Casco, Maine 04077

Send mail to JStepp@sppets.com with questions or comments about this web site.