Only the mechanism principles matter, the rest is just “stile”. You can also free hand draw the design of your choice, you cannot go wrong, as crossbows were made in all kinds of sizes and shapes. I cut the MDF on the laser cutter but the band saw and drum sander can be used also, if you really want to go medieval you can do it all with hand tools J, however you will be in the shop for a while… You can also cut the templates from some cardboard or whatever appropriate material is at hand… Take a look at the shapes and if you don’t like the shapes modify them to suit. The PDF template files are uploaded here for everybody to enjoy they are drawn to make use of these sizes. It is very smooth and free of flaws, perfect for templates if you do not require more than 4 inches in width. To speed things up I made templates from thin MDF, sometimes called flexi board. Mark them with a pencil so you don’t get confused about the orientation and cut the mortises wrong. You should have two mirror pieces that should always be assembled the same way from now on. Take another slight pass or two on the jointer on what you decide that will be the top of the crossbow to have a flat surface that is continuous without ridges or uneven. Using the Drill press use will ensure that the holes are square to the wood. From now on, predrill all the holes to prevent wood from splitting, make sure you use undersized drills for screws. Using the hand cordless drill or drill press, predrill one hole at each end about ¾ or so from the ends, so you can use the two deck screws to hold the two pieces together in alignment for further work… These “sacrificial ends” will be cut of at the end just before staining. Put the two pieces together lengthwise wide side on side, watch the grai for symmetry, and line them up good and clamp them securely. Save that wood cut off, it will come in handy later. You should have two pieces of equal length and some shorter left over piece. You can leave even more if so inclined, it makes for a better support later. Next go to the chop saw and cut the wood to the final length of the crossbow plus about two inches on each side for a total of 4 extra inches. Next take the resulting beam to the jointer and square off the two sides left, again do not take too much. Do not take too much it is not necessary as the template will allow marking and cutting of the excess wood. One bungee cord slightly shorter than the finished length of the bow, wood glue and finally some stain and varnish of your choice.īegin by taking the 2x4 to the thickness planer and taking a few light cuts on both wide sides to clean and flatten the wood. Only the 12D nails are used for the project, the screws and small nails are used for holding, and positioning templates and other the parts during cutting and assembly. For hardware I used Two 12D sized 3” long bright nails, about 6 small finishing nails, two deck screws 2.5” three drywall screws ½” long and one paper clip. Arrows or bolts were made from hardwood dowels 7/16 from the craft store. Some scraps of tempered Hardboard used for trigger and cam. The piece I found was schedule 80 which has twice the wall thickness of regular pipe found in the home centers. Other materials were, one piece of “Bender Board” a strip of MDF ¼ thick and 4” wide sold in 10 foot lengths at home centers, also one piece of PVC pipe ¾ in OD thickness, and about as long as the crossbow. Besides, the templates can be modified to suit the builder as crossbows were sized and shaped according the intended use and user. This simplifies things and people can copy the design more accurately. The shape was drawn in SolidWorks and some PDF templates were generated. I used a piece of hard pine that was actually a 2X4 clean, and fairly free of knots or defects. Some nice designs and figuring can be obtained that way. Alternately it can be made of layers of wood or plywood glued together. Ideally some hard wood was used for the Body of the Crossbow sometimes called the “Tiller”. With a little planning ahead actually it can be made for free as all the materials for all the parts and pieces can be scavenged frequently from the scrap bins. Although materials were provided, anybody can build this project for about $10.
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