Trad Gang Swap Bow 2011


For the 2011 Trad Gang Swap Bow I elected to start by doing the conversion of a 6x48 belt/disk sander to a serious bow making vertical edge sander, then test that sander by building the swap bow. The sander project was a great success and can be reached from a link on the main page. This is the bow I built using it.

 

 

I generally resaw a couple of extra lam pieces for each project, just in case... I was fortunate in that for this project I was able to find a nice set of lams pieces left over from these previous projects. Here you see a bow... some assembly required! There are four pieces of laminated bamboo and two of red elm. These will make a three lam bow. Alson on hand were two pieces of black glass and a riser blank laminated of myrtle.

 

The lams have to be ground to the specs I determined appropriate for the weight and length of bow desired. Here are two of the bamboo pieces being ground on the Grizzly drum sander. All of the lams will be ground parallel, then two of the bamboo lams will be tapered.

 

Riser being cut out of the myrtle block.

 

Using the sander's flat edge to smooth and true the bottom of the riser. I actually did this with two hands, but taking a picture required the other hand for the camera

 

Here I'm read to use the round end of the sander to smooth the top of the riser and sand the fades. The hollow curved piece closest is just the remainder of the block the riser was cut out of. I'm using the bottom of it here as a flat, true surface to back the fades as I sand them into paper thin ends.

 

Not a lot of contrast here, but if you look closely, you can see how the round end of the sander was used to bring the fade tip down to a point.

 

Finished fade tip.

 

 

What was a "bow kit" this morning is now ready to be laid up. I grabbed another previously made bamboo piece, cut it up and ground the pieces into two 12" tapered power lams and two 4" tapered tip wedges.

 

 

Final step before lay up is to stack all of the pieces together between two stiff slats of wood and run them through the drum sander to get them all of absolutely uniform width, exactly matching the top surface of the form. Nothing invites lams to slip in the gluing process like having them be of different widths!

 

 

While I was in riser cutting out mode I cut these two for future use. The wood is from a piece that has been bothering me for a long time. It's spalted sycamore, which I bought before I knew that spalted wood may not be a good choice. These are from a large plank that was just a little too dry and light for me to be comfortable using it as lams or even as riser material in most cases. However, as you can see, it's pretty spectacular. I figure these will make very pretty risers for one of my light 25 to 30 pound bows.

 

 

I'm now ready to do the layup, but it will have to wait for a couple of days. I'm overdue for a day with my wife, tomorrow, and found a shoot to go to on Saturday.

Dick


 

Well, it turned out to be Monday before I got to this point. I've shown many layups, so that part will be brief. Ah, but the grind out! Now that was fun!

 

Layup

 

I still had to angle butt the lam ends. Here I'm using a 45 degree angle jig (fancy name for a piece of wood with an angle cut on it) to do that. It's just a matter of gently sliding the lam end up into the angle an letting the belt touch it briefly.

 

 

Here's the result.

 

 

Here's the bow layed up, ready for 6 hours in the oven at 170 degrees.

 

 

I'm a fiend about preparing my for layup. I wax the form surface, then put two layers of masking tape on it. Each piece of glass also gets two layers of tape. Then the form gets a layer of clear plastic, then the actual layup. Finally, another layer of plastic. Then I place the backing/pressure strip. This consists of one layer 1/4" masonite, a layer of semi-truck mud flap rubber and a piece of 1/8" aluminum. These are taped together and go on as one unit. Because I use the "overpass" riser shape I do, my belly glass is one piece, not cut, and my backing/pressure strip is also one continuous piece. The gentle curves of the overpass allow for easy placement of the clamps and produce excellent, smooth fades.

Once the bow comes off the form, I have the option of making the bow with either my deep locator forward riser or a standard straight or dished riser. This bow will get the standard riser.

 

 

The Grindout

This was the part I was really excited to get to, as it was the real test of the new sander, which passed with flying colors. It runs much faster than Monstro, and I found it took a lighter touch, but it worked very well. I may slow it down by going to a larger pulley size on the belt drive unit, but that's a minor modification

 

 

Set up to begin work.

 

A bow fresh off the form is not a pretty sight! There are gobs of squeezed out glue (bow snot) all up and down the length. My first worry is always to get down to the riser side surfaces so I can see how well (or poorly!) the lam joins and fades came out.

 

 

Here I'm running the side of the riser section against the oncoming belt. That's important! To grind off you go against the belt movement.

 

Here's the exposed riser surface. Lam joints are OK, not as good as I like.. they squeezed open a bit. Sometimes I glue them together ahead of time, sometimes I don't. This time I didn't but probably should have. The fade looks perfect.

 

Here I've started to move up the limb and expose the sides of the lams.

 

 

If you look real carefully here, you can see the power lam... riser, belly lam, power lam, elm core lam, back lam. Also gives a better view of the fade flowing into the layup.

 

 

Once the excess glue is almost all gone, I smooht the side by working it against the flat side of the sander, working with the movement in this case.

 

 

This is what the side of the limb looks like after this operation.

 

 

The bow is still actually rough at this point. Tomorrow I'll run it through the drum sander to smooth bow sides and bring it down to the final shoulder width, which I'll decide on by floor tillering it as I go. It will probably be between 1.100" and 1.200". Once that is done I'll strip off the tape and any plastic still surviving and you'll be able to see the basic bow blank. After that will come re-taping the back with lighter colored tape and drafting the bow shape on, then grinding out the final bow shape and tillering to weight.

Are we having fun yet?

Dick


The comments coming in from the posting on Trad Gang are very enthusiastic about the details, of which I hadn't intended to show so many. However, it looks like I might as well give in and make this more of a build along. Here is the next stage of grinding, establishing the width of the bow and grinding the "overpass" off of the riser blank to arrive at a regular rear straight riser... much later, it will be come a dished riser.

 

Grinding for Width and Riser Shape

 

With the bow snot ground off, I am now feeding the riser through the drum sander to arrive at as close to perfectly parallel sides as possible and to get it down to the thickness I want. I stopped at 1.20. I'm happy at 1.10 to 1.20. Stopping here means that, as long as I keep the riser sides flat, I can run it through some more to narrow the shoulders and get a little weight adjustment if I need to drop a bit.

 

 

Some of you have probably been wondering what I'm going to do with that overpass riser. Well, here you see it being done. Most Hill bows use a 4" flat riser section. I use 4 3/4" to 5". Two reasons... first, I like to be sure I have enough for big hands and second, I tend to like long risers. This one is 17 1/2". Long risers mean a shorter working limb, which translates to a hair more speed.

Using a center finding ruler, I established the center of the riser, then slipped the ruler down until it set a line 4 3/4" long between the edges of the overpass. Then it was just a matter of running the blank through the drum sander and sanding the top of the overpass down to that line.

 

 

If you look real close, you can see just the tiniest bit of the pencil line left here. This is now a standard riser.

 

 

Because I was using a laminated riser, when I ground for truness and width, I consistently favored one side. Here you see the result. I'll cut the shelf into the wider side, thus preserving the benefit of extra strength from the laminated riser. Of course, the fact thatby laminating I was able to make use of a less expensive and more available piece of myrtle that would not otherwise be usable for a riser didn't hurt.

 

 

Big thrill time... I peeled off the lay up tape to reveal and can now begin to see what the bow will end up looking like.

 

 

Look at the riser section here, then slide back up and look at it in one of the pix before I trimmed it down. Why go to this trouble?In the lay up process, it's very much easier to get good clamp placement on the gentle curves of the overpass than on the typical sharper "ski slope" curves of the usual Hill style risers. This means better bonding, less chance of bubbles and smoother joins on the fades.

 

 


Drafting the Bow

The next step, for me, is drafting my longbow shape onto the bow blank. Most bowyers use a template for this. I like to draft it in place. I usually end up making a few small decisions about the positioning of the riser, whether to maybe try a shorter lower limb right from the start (I usually don't) and most especially about what I want the balance of the bow to be in the hand and in relation to the positioning of the shelf. So, here we go...

 

 

First step is to tape the back with a light colored masking tape. The width is now 1.20", if you recall. Whatever tape you find will be too wide. I happened to find a role of very light 2" (or nearest metric equivalent). I tape it on following one edge, then fold over gently.

 

 

A piece of 120 sandpaper rubbed on the folded edge will let you peel the excess tape right off, leaving you with a perfectly taped blank.

 

 

Using an adjustable square, I establish the dead middle of the blank and run a center line end to end in both directions. While I do the best I can to establish absolute parallel, it seldom truly is. The riser section is often the slightest bit wider, due to its greater resistance in the sander, but this doesn't matter at this point. This blank came out really well and center was nearly perfect the whole length.

Once the center line is established, I make marks at 5/16" on either side at the ends. This would be a wider tip than many would like, but it leaves me some room to play. It'll end up a bit narrower in most cases, but I like to start with the tip a bit stiff, especially if I'm not using tip wedges. The extra width lets me do a little fine tillering at the ends.

 

I pay considerable attention to the balance of the bow. I have at this point established the dead center of the riser... the verticle line, and the dead center of the bow... the short mark to the right. Here I am double checking the actual physical balance point. As you can see, it fell very closely in between the other two points. It isn't always, and I may adjust a limb length, which sometimes establishes which will be the lower limb, but I try to avoid that until later.

The point of this is that for a real longbow you will be shooting with a low wrist grip. I want the bow to balance, or have a pivot point, on the ball of your hand, just under and behind the thumb. I believe this makes arrow tuning and point on shooting easier. I've drawn in an imaginary shelf line, which might migrate to the other end at a later point, but everything has worked out very well on this bow, and if you imagine gripping it, you will see that the pressure point of a low wrist grip is going to be just about right either way. I'm very pleased about how things are shaping up.

 

With these points established, I can draft the riser. I could wish my drawing/lettering were better, but... You can see a line with an "R" above it... the center of the riser. Just below it is a line with a "B"... the balance point. Below that an "M", the measured middle of the bow.

Moving out, you see two short lines. These mark the ends of the flat section of the riser. One inch out from these lines are two more full width lines. These mark where I want the outside of the shoulders to be.


I've drawn lengthwise lines 3/16" in from the edges, the length of the flat section of the riser, again using the adjustable square. These mark the furthest in that I want to shape the riser's narrowing. On a shelved bow, the grinding into these lines will be very gentle and mostly on the edges. The side thinning of the riser will be minimal, leaving "meat" to cut the shelf into. On a no-shelf bow, I'll grind in to almost as thin as the space between the lines.

Two cautions, don't try view this drawing as proportional. There was some slant to the photo; and ignore the two diagonal lines at the edges. Those are pencil slips!

 

 

Next comes establishing the limb edges. Easy as pie... Clamp a straight edge to the limb.. just OUTSIDE of the end mark ... and slanting down to the widest point of the shoulder. Obviously, repeat for all four limb edges.

 

 

This pretty well shows you the bow plan.

 

Tomorrow, if I find the time what with working with Jesse on his bow, I'll gring the sides of the limbs and begin tillering. I won't start to shape the riser till I have established tiller and basic first draw weight. That will leave me with plenty of flat surface to mount on the top of the tillering stick.

Dick


Grinding the Limbs

 

I didn't expect to get a lot done today as my "student", Jesse, was coming over to work on the bow he's building for his dad. However, I made excellent progress in the morning, then Jesse left at 3:00 and I got a lot more done. We left off last night with the bow shape drafted on the blank. This morning I ground the limb shapes in and tested it for draw...

 

 

 

Here I'm grinding the edge of a limb, working to get down to the outside edge of the pencil line. I'm pushing the work toward the rotation of the belt, not pressing terribly hard, but letting the belt do the work.

 

As I work, the belt is pushing the tape up. To the right, where I've ground a fair amount away, you can see that the pushed up tape is starting to obscure the line.

 

At this point, I cannot safely try to work closer to the line, so I stop and use the 120 sandpaper to sand off the tape edge, just as I did when I put the tape on the blank.

 

Here is the same edge with the pushed up tape sanded off. Now I can work closer, and more carefully, to the outside of the pencil line. I'll go slower and be more careful not to have irregularities such as show here.

 

Once I've done all four limbs to the outside of the line it's time to smooth out the sides, which, no matter how much care is used will still have some irregularity due to the fact that I'm sanding a long essentially flat surface with the round sander edge. However, that round edge sands off the mass much faster than the flat side would. Now I can go to the flat side and sand with long smooth motions, carefully sanding off the pencil line.

 

 

Too far back to show well, but here is the rough finished bow shape, except for the riser, which is still untouched.

 

 

At this point I need to see what weight I ended up with. I don't want to cut nocks in yet because if my weight is too light and I have to shorten the limbs by cutting off below the nocks I'm likely to end up having to shorten it too much and ending up way over weight. You're looking at two neat tricks here that enable me to string and weigh test a bow with no nocks. The first thing you need is a tillering string with two really heavy, large leather pockets. These are connected by a heavy tillering string permanently fastened to one end and tied at the other with a bowyers knot. With the bowyer's knot you can make the string any length you need. However, the knot pulls tight with bracing and is a bear to get out afterwards!

The second thing is a way to brace the bow so that you can ge the end of the limb into the pocket. If you study the pic you will see that the end of the far limb is braced against a peg inserted into one of the dog holes in my workbench. The riser is counter braced against another peg. I stand in front of the near limb and push it forward until I can slip the pocket on. Voila! A strung bow than can be tested before I decide where to put nocks.

The first test is just to see if it's going to hang together. I don my heavy gloves and a bicycle helmet and go out in the driveway and start flexing it until I reach well beyond my normal full draw. If all feels good, I can then proceed to actually weight test it on a scale. Up to this point, everything about this bow has turned out well. However, Mr. Murphy is always with us. I came in light. The initial test draw showed the minimum weight Herkimer wanted. Since the bow is till rough, I know that I will lose at least five pounds in the finishing. If a bow comes in heavy, I know I can knock weight off by further narrowing the shoulders on the drum sander, doing more edge grinding on the limbs, or even trapping the lower 2/3 of the limbs. ("Trapping" means to grind the limb side in at about 20 degree angle toward the belly. It's a touchy operation but effective.) However, as neat as all these tricks are, they don't help if you're light! You're going to have to shorten the bow. the question is, by how much?

Herkimer gave me a narrow range to work in, and wanted a full length bow. This is the beauty of my special tillering string. I use a 1 1/4
tip on the upper limb and a 1" tip on the lower. This gives tips long enough to effectively and easily engage a stringer. The bow blank was just over 70" long. If I had cut nocks in to make full length 68" bow and then needed to shorten it, I would have had to cut off a total of 2 1/4". This could raise the weight by a bit more than ten pounds, plus leaving you with at best a 65" or 66" bow. Not having nocks to contend with, I cut 1/2" off the upper and 3/4" off the lower. The difference was a gesture toward insuring that the lower limb would be a bit stiffer than the upper. I then went ahead and put the nocks in... Nothing like confidence!

 

Here I'm cutting in the nocks, using this nifty little nock cutting jig I made. They don't necessarily come out perfectly matched, but close enough that a tiny bit of free hand filing makes them so. With this done, I strung the bow with a real 65" string and weight tested it again. I ended up with a gain of seven pounds, which put me two pounds over Herkimer's range. I could have used a bit more, but I still had a full length bow. By being careful and doing a minimum of heavy mouse and hand sanding, I could stay within the usual five pound loss for finishing, which would put me solidly in the middle of Herk's desired range.

The disadvantage is that to do this, I would be removing a minimum of material and also minimizing the curved limb edges I like to do. This will make the bow lean a bit more toward "American Flatbow" rather than pure Hill style. Ah, well... This is why I'm not a professional bowyer!

 

 


Tillering and Shaping the Riser

 

This picture has nothing to do with the swap bow... It's Jesse working on a riser on the new sander. Nice shot and I couldn't resist including it.

 

Next step is the limb limb alignment test. Just braced, the bow looked straight, string nicely centered full length. However, alignment problems are supposed to show up worst at about 16", so I have a 16" brace I put in the bow and then recheck. No problem here. Fortunately, I have rarely encountered this problem. Bless narrow limbed, deep core longbows!

 

 

Final check on the tillering board. Lower limb is to the right and shows about 1/2" less bend than the upper, which is a bit more positive tiller than I normally like. I'll do a bit of extra sanding on the lower and should end up between 1/8" and 1/4".

I

 

I usually like a narrower tip than this. It will be narrowed a bit, but again, because I'm trying to lose a minium of weight in the finishing process, I can't just slim the limb down. This is the upper tip.

 

And the lower tip.

 

Next I shaped up the riser, slimming it and curving the back edge inward. You'll note that I carried the gradual narrowing in to the shoulder further up the limb than I had drawn on the drafted plan. It just looked right. It's always easier to start short and then go long than it is to do the reverse! This is going to look real nice.

 

The belly side has been rounded and the limbs brought in to what will be their points.

 

 

A tiny bit more sander work cut in a gentle, minimal dish and left the riser feeling real good in the hand.

I always try to do something new or different on every bow. This piece of myrtle somehow didn't thrill me. It's too plain and gray. I decided to try staining this bow, something I've never done before. the top piece of wood is a leftover from the riser blank with the stain on it. It will make the myrtle almost match the red elm accent lam and will also stain the edges of the bamboo lams a more yellow tone.

 

 

Oops! I started to say that this was it other than finals sanding and finishing, but I just realized I still have to cut in the shelf. I'm sure those following this as a build along will want to see that, so I guess I will be posting one more set of pics. I have a shooting student coming down tomorrow so I guess that will be Friday.

The finishing process will take longer than usual as I don't want to use TruOil on top of another brand/type of finish. The stain is a MinWax product and the recommended over finish is MinWax Wipe On Poly, which I've used on bows before. It just takes longer to dry between coats.

Dick


Cutting in the Shelf

I got a real early start this morning and my shooting student wa sdelayed as his trip involved a ferry, so I got a lot done. I got the shelf cut in and all of the mouse sanding done. All that's left is the hand sanding to prepare the wood and glass for finish. The next set of pix really will be the final pix in this presentation.

 

 

I cut the shelf with these rasps and files. It's really hard to find a quality round rasp of a good diameter. This one came from Italy via a lot of searching on the internet. The long square file has one edge ground "safe" on my knife grinder, so that I can file a selected surface without damaging the one next to it. The big rasp is not the famous Nicholson, but one I found that was much less expensive and has proven fully adequate.

 

 

For this operation I mount my gunstock vice on the bench, again using one of the dog holes. Note the support blocks. These live under the bench and can be arranged to provide support for a variety of operations. Here, they solve a problem that resulted from a mistake on my part. I dished the riser too soon. I should have waited till after this operation so that the riser still had two flat sides. With the dish, much of the contact surface was gone and it wasn't too stable in the vice. With the support, I could grip the riser relatively lightly and still cut with the rasps.

 

 

Always cut toward the center of the bow, cutting only on the inward stroke. It's not a big problem on the wood, but if you try to cut on an outward stoke on the glass, you'll pull fibers from the glass. Go slow or you can get chatter marks in the wood. Here I have started the shelf cut with the round rasp on the wood, just below the end of the glass, then turned the bow around to cut the glass side in.

 

 

Glass side has been cut in. I leave a very slight crown to the work, so that the arrow will have minimal wood contact. The shelf has now essentially been established and only has to be cleaned out to final shape.

 

The lengthening of the sight window is accomplished with the big rasp. Here I've tipped the rasp up so you can see the cutting surface. This is actually the fine side! This rasp is used very carefully and slowly, with little pressure, essentially letting its weight to the cutting.

 

The sight window has been opened up and what is left is to clean up and shape the edges and the bottom, fully establishing the crown on what will be the side plate. Cleanup is also needed in the bottom corner where the shelf joins the sight window.

 

I used a narrow round file to clean up the inside edge, then used the square file with the safe edge to add a gentle arc to the surface of the shelf, again so that the arrow will have minimal surface contact. The shelf is 1/4" deep plus or minus depending on how the work goes.

This whole process took just over half an hour.

 

 

Next step is to sand the riser and the limb edges with the mouse sander, starting with 50 grit on the edges to round them from their square profile to a curve or angle in from both back and belly. I normally do a bit more of this limb shaping than I did on this bow since, as you will remember, I am trying to lose as little draw weight as I can. Sanding proceeds with 80, then 120 and finally 150 grit pads. When on the 80 grit, I use the mouse to shape up the tips and make them attractive. Note the support block clamped in the end vice. This give you a more solid approach to the limb edges and prevents the limb from picking up the sander vibrations and rattling against the bench top, which reduces the effectiveness of the sander and is also annoying.

 

 

Next step is the hand sanding, which will start with 150 grit paper, going over the riser and the glass, to take off the glass protective glaze so that the finish will adhere. Additional hand sanding will go through 180 to 300 grit papers. Two coats of finish will be applied and rubbed out, then the lettering will be put on, then two more coats of finish. Next set of pix will be the finished bow, ready to be shipped.

Dick


Finished Bow

Meet "Trad Pole"

Hurray! The long journey is over... Here is the finished bow. There is one more picture that isn't shown, the specs, because that would perhaps enable the swap recipient to identify his bow before he got it. Also, as I processed the photos, I realized I should have given it a final rub down, but what can I say, I was over-anxious. It still has some dust streaks and smudges from being on the bench for the wrap and string making. It'll get rubbed down and shipped tomorrow.

 

 

Unstrung... sorry for the bright light, but it does show the profile.

 

Strung

 

This shot shows the colors... black glass, boo, red elm, boo, myrtle riser.

 

Reverse side

 

I was going to name it Trad Stick, but it didn't like that...

 

As mentioned in the build notes, I like my tips narrower, but I was trying to maintain draw weight, which came out right in the middle of the recipient's wanted range.

 

 

Jeff showing the bow at full draw.

 

I shot the first one, Jeff shot the next two. I told him to stop for the photo. Heck, I ain't stupid!

 

There you have it. It's been a good, fun build and actually and makes a good update to my building practices.

Captain Dick