BUILDING  CROSSBOWS  1         

         WARNING!!!    The crossbow I am going to build does not have a mechanical safety device.  The only safety system used on the early crossbows was one where you placed your hand between the stock and the lever. The plans are based on a replica and are for references only. If  you wish to build a crossbow for hunting all states require a mechanical working safety device.

                                                         REMINDER         SAFETY  FIRST

      I build two styles of crossbows. And the biggest difference is the trigger systems. The one I am  going to build in this part is the lock notch style.

A list of tools you will need.  Chainsaw, circular saw, hacksaw, small hand plain, drill, 5/16" bit, 1/4" bit, 1/8" bit, 5/32"drill bit, 1/2"wide wood chizzel, pencil, square, angle grinder with flap sanding disks, sand paper, pocket knife, shaving horse, or vice. c-clamp, ruler, framing square, and draw knife ( if you do not have a draw knife, refer to knife making).

     Now you have your tools, lets get started. First the bow, also known as a prod, I am going to use a wooden bow in this project. (There are places you can buy metal prods if you choose not to make a wooden one.)

      I start by going into the woods and cutting me a piece of hickory about 6" across and 34"length. Then I take the piece of hickory home and split it into 4 even pieces just like splitting firewood. Then I place the quartered pieces inside of a dry place out of sunlight to season for 1 year.  After the wood is seasoned I am ready to cut out my bow. First I start by placing the quartered pieces of hickory (also known as a bow staff) in the shaving horse and use a draw knife to remove the bark and outer layer of wood, becareful not to cut into the white wood. 

Now that you have removed most of the bark, take a pocket knife and take your time to remove the rest of the inner bark down to the white wood making sure not to cut into the white wood because this will be the back of your bow. This is where the bow gets its strength, the fiber should run the full length of the bow, it should follow the growth ring.

Now that I have the back of my bow pretty much done, I turn the staff over in the shaving horse and begin by removing the wood from the belly side of the bow. Then I place the staff on it's side and remove the excess wood from the sides of the bow. Below is a set of drawings and dementions that will give you an idea of how to shape out your bow.   

I use the dementions in the drawing above as a guide line. Since you are using wood and you must follow the grain of the wood in order to achieve maximum strength, you will not always get the exact dementions as shown in the drawing above. You might get a slightly different shape in your bow. After I get the bow close to these dementions I take my pocket knife and cut notches in the tips of the bow for the string. Once I string the bow, I will pull on the string with my foot on the bow and see if the bow bends evenly, if one side is too stiff I will use my knife to scrape away excess wood from the belly of the bow until the bow bends evenly, or if I have a desired weight for my bow and the weight is higher then I will remove excess wood from the belly side of the bow until I  achieve my desired draw weight. Here is a picture of the 80lb, 28" long self bow for this project.

                                                                          THE STOCK

         Usually the stocks of the crossbows varies in length, width, and thickness depending on the style and drawweight. The stock for this project is 1 1/8" thick by 3 1/2" wide by 28"long. Normally for most hunting bows the stock would be 1 1/2" thick and the type of wood used for the stock varies. For a first time crossbow stock, I recommend a pine 2x4 that you can purchase from a lumber yard, yellow dense growth pine. It's actual plained size is 1 1/2" by 3 1/2".  The woods usually used in hunting crossbow stocks are woods like oak, cherry, and  ash, and most any good straight hard wood. For this project, I have chosen oak. Here is a drawing with dementions that I will refer to from time to time, as I take you thru the building of the stock.

                                                                         REFERRENCE PAGE

The first thing in designing your stock is to figure how much draw length you will have and the way I figure this, is half the distance of the length of the bow, so if you have a 28"bow you will not want your draw length to exceede 14", or if you have a stock with 14" from the front of the stock to the center of the trigger, you would want a bow no shorter than 28". The first cut on your wood for your stock should be the front of the stock. This will be determined by drawing a straight line from where the trigger notch is to the center of the front of the bow,( this is line A), then by drawing a perfectly straight line at the front of the bow, (this is line B),  this line should be perfectly square with line A.  As shown in figure C, in the drawing above.After you have cut the front of your bow, now it's time to determine the shape of your stock, You can use the drawing above for referrence. I draw out my stocks on a piece of cardboard, then cut the cardboard out with scissors and trace it on the side of the stock as shown below.

Now I take a ruler and measure back from the front of the bow on line A, 1/2", then I draw another line perfectly straight with line B. Then measure 1/2" from the top of the stock down, then from the 1/2" mark down, I measure another 1 1/2" down. and make another mark. Then I put the stock in a vice, and use a circular saw to cut out the 1 1/2" area. This will be the slot for your bow to set in. Shown in figure C, at the front of the stock in the referrence drawing above. Then I measure another 1 1/2" back on line A, from the slot and drill a 1/2" hole thru the stock, also shown in figure C above and the picture below.

 Now I measure back 14 1/2", on the top from the front of the stock and make a mark in the center of the stock where I drill a 1/4" hole all the way thru the stock from the top. Then I take a chainsaw, and rough out the shape of the stock.

  I use a grinder with a flap disk to smooth out the shape. Then go back to the top side of the stock,  where you drilled your hole for the trigger draw a line straight across the stock where the hole is drilled thru.  Then measure back 5/16" and draw another line straight across, next use a circular saw with a 5/16" depth cut to cut out the notch and use fine sand paper to smooth the edges of the notch. Now comes the tuff part. If you have a rouder or a table saw to cut the slot for the barrel, it would be much easier. But it can be done with a circular saw, that's how I'm going to do this one. First I make a mark with a pencil in the center of the stock from the 1/4" hole to the very front of the stock. Then with the circular saw set for a 1/2" depth I make 2 passes, then with sandpaper and a knife I make a 3/16" by 1/2" slot from the front of the bow to the trigger. The barrel must be straight as possible to achieve accuracy. This is what your stock should look like, (below).

 To cut the slot out for the lever which is your trigger, go back to the referrence page to figure D, which is the bottom of the bow. There is a slot that is 5/16" wide and is 1 1/2" deep by 3" long. You can also view that slot on figure C.  In figure C, c,d, and e, represents 1/8" holes that you have to drill thru the stock. These holes will accept #8 common nails for pins. D pin will be the pivot point for your lever. The hole in the lever will be 5/32". The lever is represented by F.) F, (the lever) can be made from a piece of 5/16"steel, square or round  stock. Depending on the taper of your stock will determine whether the lever will have to be bent or not. E is the lowest point which the lever can drop to, it is also a #8 common nail. G, is a 1/4" pin by 1 3/4" long. Take G, which is the slide pin, and measure down 1/4", make a mark, then measure 1", and make another mark. Use your grinder to cut out an 1/8" deep notch between the 1/4" mark and the 1" mark in the side of the pin. Then measure from the bottom of your 5/16" trigger notch straight down 1/2". This is where the 1/8"hole that represents C, is drilled. So when the push pin is the 1/4"slot and C pin is in place this will secure the trigger pin so that it doesn't fall out. Now that you have the trigger system together, it's time to mount the bow. With you bow strung you should have about a 4" brace heigth. This is the distance between the string and the center of the bow. To mount the bow to the stock, use a thin piece of leather to wrap around the center of the bow, and slide the bow into the notch in the front of the stock. Then I use a 1/8" braided nylon string about 6' to 8' feet long. I run the string thru the 1/2" hole in the front of the stock, I pull the string so that there is an even amount of string on both sides of the hole in the stock, I take the string to the front of the bow, and I crisscross the strings back down the stock and run one in thru the hole then the other, now you should have even amounts of string on both sides of the stock again. Now take the string to the front of the bow, go around the bow and straight down the stock and back thru the 1/2" hole, Repeat these 2 steps over and over until you have about 10" of string on each side. Then wrap your loose ends of string on each side of the stock around the wrappings of string between the hole and the bow. Tie 4 to 5 knots, as you wrap them around the wrappings. This is how you tighten and secure the bow in place. How this system works is, when the string is in the notch it pushes the push pin down and when you pull on the lever it pushes the pin up and lifts the string out of the notch and sends the bolt on it's way. Here is a picture of the finished crossbow.

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