Wednesday, May 27, 2015

Make a Continuous Loop Bowstring – Part 1

I’m not sure when the continuous loop bowstring came into being.  If I had to guess, I’d say it was in the 1960’s when modern longbows were in their prime.  If you buy a longbow today it will probably be equipped with a continuous loop bowstring.  What are the advantages of a continuous loop bowstring?  For one thing they are extremely strong.  They are just one continuous loop of string; no splices.  The loops are not spliced in as on a reverse-wrap bowstring, and you have the same type of loop on both ends of the string.  The continuous loop bowstring is also one of the quickest and simplest bowstrings to make, probably why they were so popular with mass producers of bows.

It takes a couple of pieces of equipment to make a continuous loop bowstring, so if you only need one bowstring you are probably better off to just buy one.  I’ve seen them in stores that carry traditional archery supplies for around $15.00 US.  If you make a lot of bowstrings, it is far cheaper to make the two simple pieces of equipment and make your own strings.  This post is a tutorial on how to make one of the two pieces of equipment that you will need.  In the next post I will show you how to make the other piece of equipment, and in the third post we will go over how to make the actual string.

The first piece of equipment you will need is a serving dispenser as pictured below. 

Serving is a small cordage that is wrapped around the loops to strengthen them and hold them closed.

Serving is also wrapped around the center portion of the string to prevent wear at the point where arrows are nocked.  You can buy a serving dispenser, but if you have a few simple tools it is super easy to make one.  All that you need is a small strip of light gauge metal, some tin snips, a drill and drill bit, a bolt and wing-nut, and four washers.  I used a scrap of metal and some odds-and-ends from my shop to build mine for zero dollars.

The first thing you will need to do is buy a spool of serving thread so you can build the dispenser to the proper dimensions.  I bought my serving at Academy.  I’m sure that other stores carry serving, and you can also order it on line.

My serving spool is two inches long.   

The dispenser will have to accommodate the length of the spool plus about an eighth of an inch of play on each end.  In addition I will need to turn the metal up about an inch and three-quarters on each end to hold the spool.  With these dimensions in mind, I cut a strip of metal 5 ¾ inches long by 1 ¾ inches wide.

I used a ruler and laid out the strip into three sections; 1 ¾” on each end and 2 ¼” in the middle.

I drew an X in each section to find the center.

Then I used a hammer and punch to make a pilot dent in the center of each X.

Now we are going to drill some holes in the strip, but first we need to get our other hardware together so that we can make sure that the holes are the right size.  You will need a bolt that is long enough to go through the length of the spool plus about a half inch.  The bolt also needs to be small enough in diameter to fit through the spool without binding. 

When you find, or buy, the right size bolt, nut, and washers; you will need a drill bit that is just a little larger in diameter than the bolt. 

Use this bit to drill a hole in each of the two end sections, and drill a smaller hole in the center section.

The next step is to put the metal strip in a vice and bend the end sections up at a 90 degree angle.  Actually, I bent them a little past 90 degrees, and then bent the tops out a little by hand.  This gives the ends a slight bow so that the center of the ends will contact the spool better.

Use a file and/or sand paper to smooth out the holes and remove any burrs.  I gave my dispenser a coat of silver spray paint, but this is not really necessary.

Now you’re ready to assemble the whole thing.  First run your serving thread through the hole in the center section.

Then use the wing-nut, bolt, and washers to mount the spool.  Put a washer on the inside and outside of each end section. 

Use the wing-nut to adjust the tension on the spool.  The tension is right when a slight tug will pull thread off of the spool; but when the dispenser is held up by the thread, more thread will not slip off on its own.

In the next post we will build an adjustable string jig.  Super simple.  It takes about 15 minutes.

Friday, May 8, 2015

Putting a New Handle on a Sledge, Axe, or Hammer

I use a sledge hammer for a lot of things on my farm.  I drive t-posts with it, I bust up rocks with it, I split fence rails with it, but mostly I use it and a couple of wedges to make the first split on large blocks of oak that I am turning into firewood.  Maybe you have better hand-to-eye coordination than I do; but every five years or so, my sledge handle ends up looking like this:

So, I find myself needing to put a new handle on it.  The process outlined below is the same method used for replacing handles on axes, hatchets, and hammers.

Before you start you will need a new handle.  You can make the handle, or you can buy the handle.  Making a handle is considerable work.  You must have the right kind of wood, usually ash or hickory, and you must have the wood already seasoned.  I make or re-purpose handles for rakes, hoes, hatchets, hammers, and etc., but I prefer to buy handles for axes and sledges.  The hardware store prices are way too high for me, so I always keep my eyes open at flea markets and garage sales for tool handles.  If you buy handles this way you must know what you are looking for.  You only want the ones that have straight grain, no cross-grain, no knots, and no cracks.  Most of those guys at flea markets are selling factory seconds, so you really have to be choosey.  I went to a flee market a couple of years ago and one of the sellers had barrels of tool handles.  I must have looked at 200 tool handles, and I came away with two axe handles and three sledge handles. 

So now you have your new handle.  First thing to do is remove the old handle.  I clamp the sledge in a vise and use a hand saw to cut the handle off right at the base of the head.

Then I set the head on top of two boards, top down, and use a hammer and a drift bar to drive the old handle out.

Be sure and save the little steel wedge that is in the top of the handle.  You are going to use it again.

Your new handle will not fit into your sledge.  It will be too long and too big around.  You will have to shape it to fit.  I lay the head down on the handle where I want it to sit at the bottom and then I mark the top for cutting.  I always add a quarter inch to the length.  You may need that quarter inch, and if you don’t you can cut it off later.

When you have sawed the top off of the handle, look at the slot that your wedge goes down into.  It may be too short now.  You want this slot to be about half the depth of your head, or a little more.  If it’s too short, take your trusty hand saw and make it a little deeper.

Now comes the slow part; sizing the handle to fit into the hole in the head.  The best way that I have found is to clamp the handle in your vise and use a wood rasp to slowly work the handle down.  I rasp on about the top half-inch of the handle until the head will just barely fit on.

Then I take a hammer and drive the head on a little bit, and then pull it off.  You will see darker spots where the wood has been compressed when driving the head on.  Rasp very lightly on these areas and then continue rasping down another half-inch.   

Drive the head on, pull it off, rasp a little more, etc, etc, etc.  It takes a while, but it will insure that you have a good tight fit.

When you have the head seated down tightly on the handle, it is time to cut a wedge to drive into the slot.  Hickory is best for this.  You may be able to use the portion that you cut off of the top of the handle to make a wedge.  If not, you can use oak or even pine.  When cutting the wedge make sure that it has a smooth taper and is not too wide at the top.  You want the wedge to contact the sides of the slot all the way down.  If the wedge is too wide, and tapers down too quickly; it will only be touching the slot at the top, and it will pop out during use.

I like to coat my wedges with carpenter’s wood glue before I drive them in.

When you drive the wedge in, place a small board on top of it and use your hammer on the board.  If you hammer directly on the wedge it will likely split.

When you have the wedge firmly seated you can cut off the excess wedge and handle so they are flush with the top of the head.

The last step is to drive the little steel wedge into the top of the handle.  It should be in the center of the handle and perpendicular to the wooden wedge.

Set the sledge aside for a day so that the glue on the wedge can dry thoroughly and you should be good to go for a few more years.  Oh, and be sure too keep that old handle.  At some point in the future you can cut it down and use it on something else that breaks.