How Do You Enlarge a Pattern?

[judaspre1982]

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[baddlad]

the easiest way is to find a photo copier that has that function on it. or you could open it up in paint and then go to View then resize/skew, and make it bigger.

[baddlad]

actually if you really want it done right take it to kinkos and they can make it the right size 1 to 1 scale. However if you don't want the expense then you will have to put it on at least a couple of pieces of paper. I don't know if they make copier paper 17 X 35 inches.

[judaspre1982]

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[a1gutterman]

actually if you really want it done right take it to kinkos and they can make it the right size 1 to 1 scale. However if you don't want the expense then you will have to put it on at least a couple of pieces of paper. I don't know if they make copier paper 17 X 35 inches.

Or, you can use one of these.

[reible]

This is really a common method of making a scale drawing fit in magazines or books. It predates the use of computers and copy machines and is really a simple matter to do by hand.

Each square on the scale drawing is designed to be 1" on the finished drawing. In this case I count 17 squares tall and 35 squares wide, or 17" x 35".

You will need paper or plywood or hardboard material of that size. You then layout the pattern on the paper/plywood/hardboard with the 1" squares. Then you simple count squares or factions of squares to reproduce the pattern.

As an example if you look at part F starting at the left side we can see that tenon is going about 1-3/4" by 2". Your line would start half way up in the first square, one quarter the way in and would run half way into the third square. And you work your way across the part.

You can of course go direct to your work piece but generally I like to make a pattern and save it. If you keep the pattern material to say a 1/4" or 1/2" you then can sand it and use it with your router/pattern sander to clean up the edges... especially curved ones. Of course the initial cuts are done by tracing the pattern.

Ed

[a1gutterman]

This is really a common method of making a scale drawing fit in magazines or books. It predates the use of computers and copy machines and is really a simple matter to do by hand.

Each square on the scale drawing is designed to be 1" on the finished drawing. In this case I count 17 squares tall and 35 squares wide, or 17" x 35".

You will need paper or plywood or hardboard material of that size. You then layout the pattern on the paper/plywood/hardboard with the 1" squares. Then you simple count squares or factions of squares to reproduce the pattern.

As an example if you look at part F starting at the left side we can see that tenon is going about 1-3/4" by 2". Your line would start half way up in the first square, one quarter the way in and would run half way into the third square. And you work your way across the part.

You can of course go direct to your work piece but generally I like to make a pattern and save it. If you keep the pattern material to say a 1/4" or 1/2" you then can sand it and use it with your router/pattern sander to clean up the edges... especially curved ones. Of course the initial cuts are done by tracing the pattern.

Ed

Or, you could use one of these.

[reible]

Or, you could use one of these.

Hi Tim,

We did notice you the first time.

Actually I have two of these and neither would have the range necessary to make this size pattern in one step. In addition it could have several alignment issues because of this, having to step it to get the reach for layout. (Actual I have a third one but it is for a router).

I have no idea how large the shopsmith one is so maybe this wouldn't be a problem.

Anyone want to give it try here is an app that will let you play at the computer:
http://www.ies.co.jp/math/products/geo1 ... panta.html

Ed

[edflorence]

Hi Ed...

Your description of enlarging the pattern was quite clear. I have used that very method a number of times, and what I find really helps when drawing in the enlarged curved sections is to simply "plot" a few points on the new curve and then use a flexible batten to "fair" the points together smoothly rather than trying to freehand the curve. "Fairing" is boatbuilding speak meaning "connect the dots nicely." The enlarged curve may not be precisely identical to the original pattern, but in most cases its plenty close enough.

I have looked at the pantograph method and wondered whether or not it really would be more accurate or easy than the grid method. Seems to me it would require a very steady hand to be more accurate. In the pre-computer days we used to use a device called a planimeter to derive the area of plane figures. It worked a bit like the pantograph and required the draftsman to trace the figure with a stylus. As the stylus traced the figure a series of gears turned a calibrated dial. When the stylus had gone all the way around, the dial reading was multiplied by a scale factor and voila! the area of the figure was found. With the planimeter, however, accuracy was obtained by making a number of passes around the figure and then taking an average of all the readings. Seems like with the pantograph you only get one shot at it, so the accuracy of the tracing depends entirely on eye/hand coordination and caffeine-free nerves. Maybe I am missing something, but I think the grid method of enlarging a pattern is hard to beat. I have never used a pantograph though, so I would be interested in hearing about your experience with the it.

[a1gutterman]

...Actual I have a third one but it is for a router...Ed

How easy is that one to use? It seems like the weight of the router wood be hard to guide around from "the other end" of the pantograph. Do you do it alone, or with help?