OK Guys, "here we go"! Tonight I am going to start the building phase of the Phantom II .12 boats. Due to a dilemma that I can't get past in my mind, I will be building 2 different .12 boats. One will have rear sponsons with a 1/2" wide ski and one will have no rear sponsons with a 1" wide ski. Here is a hot topic so I look forward to any comments or ideas you guys may have.
I don't know if some of you have ever scratch built a model before but if you haven't and would like to, this build will likely be very helpful to you. I first designed the boat on my drafting table then I overlay the 3 view drawing with tracing paper and traced off all the shapes to build the individual parts. Keep in mind that any parts that angle of curve will be longer or bigger than they appear on the plans. In this case refer to the end view (either front or rear) to determine the true length or height of an angled part. In the case of curved parts, it is best to allow a little more in length or width to allow for the increased area caused by the curve. In some cases such as the chine (angled area on the outside) of a sponson, the angle becomes compound (curves in two or more directions) and it is best to weight until the sponson is partially built (to the point you need the chine part) and trace the area of the chine onto a piece of the appropriate wood. Be sure that your tracing is a little oversize. This will insure that the part does not come up short in some places. Hold on, don't say "well hell the **** thing is too big"! Too big is good. Go ahead and glue it in place leaving a slight over hang all the way around. When it is dry, you can sand off the excess leaving a perfect fit and a perfectly sharp edge. Really listen to me here! Use a sanding block where ever possible. To hand sand the part will insure you will come out with waves, imperfect edges and generally an inaccurate shape.
OK, lets take a minute here and talk about sandpaper. In my opinion there is two types of sandpaper, course and fine. Course paper for removing excess material and shaping and fine for finish work. I use two sanding blocks for course paper, one with 40 grit, "yes 40 grit", and one with 80 grit. The 40 grit will make quick work of excess materials, excess epoxy and shaping blocks, etc. The 80 grit will shape the wood such as sanding perfectly sharp edges, sanding rounds or contours, etc. Next I have one sanding block with 120 grit sandpaper, this block does the finish shape. Now is the time for 320 grit sandpaper in the palm of your hand. I use 320 to put the final smooth finish on the wood. I say use your hand instead of a block because it will allow you to feel slight imperfections and correct them. By starting with the course grits then progressing to the fine grits, your build time will be greatly decreased and your accuracy will go way up.
I have attached pictures of the first stage of my build. After tracing off most of the parts, I use spray adhesive (contact cement) to attach the tracing paper (with the individual parts drawn on it) to the correct thickness and type of wood. Let me back up here for a minute, before attaching the tracing paper, I cut (on my table saw) how many pieces of wood I will need for that particular part, 2 each, 4 each, etc. I cut the wood slightly larger than I will need for the part. After the tracing paper pattern is glued in place (to the top piece of wood) I stack the wood perfectly and hammer a couple of small brads or finishing nails through the pattern. Do this on a piece of steel, if you can, and it will slightly flatten the sharp end of the nail making it where the pieces will not come apart when you are cutting them. Next, I cut the wood parts out on my band saw. You can use a band saw, jig saw, power coping saw, etc. Just make sure that you have a very fine tooth blade (having the most and smallest teeth) in your machine. This will make the job much easier and will curtail splintering. After I have cut the pieces of wood and before removing the brads, I block sand the edges (very carefully) to insure the accuracy of the shape. By sanding the parts before removing the brads, it insures all the parts are identical. They are either "all right or all wrong", but at least they will match from side to side, LOL!
For rectangular parts, I just cut them on my table saw and generally leave them a little too long. Like the saying goes, "I have cut it off 3 times now and it's still to short", LOL! Anyway, look at he pictures and you will see where I am at. I will post more as I do it. Joe
