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| general hunter 1:48 scale laser cut kit | ||
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| daves |
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 Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | The hardest part would be cutting the ratchet by hand so i thought if this could be done the rest of the windlass is just sanding the flat surfaces along the barrel. The holes in the barrel is also a simple task of drilling a hole and squaring it off. The process of cutting the teeth begins with making a knife cut down the center between two lines. Remove one side of the tape close to the line Begin by making two end cuts, starting at the center push the point of the knife straight in and then make a slanting cut towards the line. Go back and make a deeper cut along the center tape edge. Make the first cuts in the area where the tape is removed. Cut straight down along the edge of the tape between the lines then cut at an angle towards the line, what your doing is cutting the side of one tooth.     | ||
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| daves |
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| Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | Once you have the valley between two teeth cut out it is just the process of repeating the steps all the way around the windlass. Thickness of the lines is actually about the thickness of the top edge of the teeth. When first cutting out the teeth I stayed a little back from the lines. This was done to save a little material to clean up and straighten out the teeth once they are all cut. The little curl of wood shows how small the cuts are. The process is to deepen the cut between the lines and take small slices leaning towards the pencil line, this is giving you the V shape of the teeth. Don't try to hog out the wood just take little shavings at a time, hogging out the wood will end in chipping the edges. By looking at the V shape you can see why the first end cut is a stab in the center and a slanting cut on either side of center to the pencil lines. The wood i am using is Cherry and as you can see it holds its edges. I did say not to use really hard woods like Boxwood but yes you can use it. carving it is just a bit more difficult but possible if you take your time.      | ||
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| daves |
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| Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | This was just playing around and i found to carve the older style windlass with 8 sides on the barrel was a bit harder to get all the sides even and with a taper so now i am going a little higher tech and use a laser. Model ship building or any model building has a part that is rarly talked about and that is ways of doing things with tools and jigs which is just as creative as building the model. This is experiment 2 As a build log to show how things are done using a laser cutter is not quite fair because how many people have laser cutters. Then again there are services provided just like 3D printing where you can send a cutting file and get your stuff cut so learning how to use a laser might be useful. Looking at the cad drawing we need the colored in parts. These parts in cross section are wedges and the laser has limitations as to what it can do. One of those things are lasers can not cut on an angle. By drawing in CAD you can see how a drawing can be converted into a cutting file so the parts were copied and arranged for cutting Using the size of an Exact-O blade you can see these parts are small. A 1,500 watt laser cuts really fast so before you start and stop the machine you have way more parts than needed. But it took like less than 2 minutes. Looking at the cut out part it is square and we need an angle.    | ||
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| daves |
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| Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | back to the drawing, looking at the drawing you have to take a flat 2D idea and visualize what is going on in 3D The stave is laser cut at a taper the squares at the ends are end views next line is taking the squares and rotating them so the bevel is in a horizontal plane. The red areas is where the squares are cut to make the first bevel. the horizontal plane is notched for the squares to sit in the squares, once the first bevel is cut are rotated and set on a horizontal plane once again. The pink area is cut away to produce the second bevel. last drawing is the resulting jig. The 1/8 square notches on either side are for guides It works on paper now lets see how it works for real  here is what the jig looks like    | ||
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| daves |
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| Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | here is how the jig is used, just sit the stave in the notches and either sand or cut down the bevel. When the first bevel is cut flip the jig over and place the stave in the second set of notches and cut the second bevel. In the last photo of the staves notice a laser when focused will start cutting very sharp and clean. Turn the cut over and the beam leaves the wood like a blow torch. when placing the staves in the jig make sure the good side of the square holes will be on the outside.   | ||
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| daves |
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| Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | The idea is to use the wood rails as a guide and slice down the stave.  Once your done with cutting all the bevels then fold the stave up into a barrel   | ||
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| daves |
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| Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | sounds easy enough and the idea almost worked except for one little problem. Looking at where the arrow is pointing there is a dip in the wood guild rail. i used Boxwood thinking it would be hard enough not to nick or wear. This did not take long to mess up the guild rail so down to the junk box to look for a way to improve the idea. In the last photo the wood guild rails did not hold up well to the cutting of the staves and nicks and dents soon occurred leaving the bevel uneven which defeats the purpose. I have a junk shelf where i toss odds and ends of stuff because you never know what might come in handy. I found a pieces of 1/8 diameter steel rod and thought oh yes that's it. Some folks wonder if going through the trouble of making jigs is worth the time and effort, simple answer is if you have to make more than one identical part yes it is. In this case a jig is far easier than cutting 16 staves exactly the same free hand which not only has bevels but the entire stave tapered. I used a stave to make sure the jig ends were not to far apart and the steel blocks to line everything up. using the steel rods gave me a perfectly flat guide rail that i could not nick or dent plus the edge of the blade just glides down the rails giving the bevel a perfect flat surface. I stuck masking tape in the notches to hold the stave in place.     | ||
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| daves |
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| Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | These photos are about watching the curl. Wood grain is like the nap on fur. If you go against the nap the wood will cut in chips but if cut in the opposite direction it will shave off in fine curles. When i cut the bevels on the staves i took a very light cut in both direction to test if the direction would matter. Always use a sharp knife, i went through four number 11 Exact O blades to cut the bevels. The blades were still sharp after cutting 4 staves so i just reuse them for not so critical cutting.   in these photos the high point is where the grain just does not want to cut smooth in either direction. what i did was try to move ahead of the spot which is the cut on the left. You can see it is not going to cut in a smooth curl. Next cut i moved a little forward and tried again, the cut met resistance where it stopped, again not giving me that smooth curl. The wood is actually splitting away and not cutting. In some cases it is the way the grain runs it could also be the blade getting dull or just to big of a cut. This is the warning that something is not going to go right. the third cut was disaster and chipped out a big chunk at the end and the stave ending up scrapping it. When i first felt the resistance to the cut i should have stopped. Woodworkers say spots in the wood like this are like ruts in a dirt road, no matter how many time you drive over them to try and flatter them out the worse it gets. There is a trick to it change the angle of the cut so your cutting towards the edge of the piece and not to the end. You may have to try different angles and direction but when you found the right cut the spot just slices off.     | ||
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| daves |
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| Registered Member #105 Joined: Wed Jul 15 2009, 12:01pmPosts: 2624 | This last photo is the moment of truth will all the bevels be correct and will the barrel come together. First thing i realized was these pieces are really, really small and getting them in a perfect circle is not easy. After several tries i got up to walk out of the room and there in the corner was the answer. My conga drums are close to the shape of the windlass barrel and they sit in hoops with legs about 18 inches off the ground. I looked through "my might need it some day pile" and found a plastic circle template. I fit the staves into a circle and got all the staves lined up then pinched the end together.  | ||
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| Gary M |
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| Registered Member #4198 Joined: Tue May 07 2013, 10:50pmPosts: 908 | Brilliant work on explaining the windlass. So many great lessons in here! Thanks! G | ||
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