BigPrint usage tutorialBigPrint is a program to for making large and accurate multi-page printouts on ordinary ink jet and laser printers.
Scaling and measuring an existing drawingIn this example we are going to prepare a drawing of a rocking chair from the Internet to make a 1:1 printout spread over many pages.
Setting the scaleFor most images, the actual 1:1 resolution in dots per inch or dot pitch is not known. But BigPrint makes it easy to scale an image based on known dimensions of features in the drawing.
Preparing for printing
Once an image is scaled, you can proceed directly to printing;
however, you may want to optimize the drawing for printing.
|Cropping is a two-step process. Before the image can be cropped, an area of the image must be selected. Start by selecting "Select" under the Image menu.|
|Once select mode is entered, drag across the image with the mouse to select an area of interest. Once a rectangle is selected, you can make fine adjustments by dragging the edges of the rectangle. You can also zoom in and out (with the mouse wheel) as you make adjustments to the selected area.|
Next select "crop" from the Image menu to complete the cropping.
If you don't like the result, you can undo the crop by selecting "Undo crop" from the image menu.
|In this example, our cropped image now spans four pages. We could probably re-crop it to get it down to three pages wide, but if we switch the paper to "landscape" format, it would fit on three pages easily.|
Select the "Print settings" from the Print menu. This will take us to the
print setup window shown at left.
Now click on the button near the top of the window where it says "Landscape".
The main window will immediately adjust to show how the image fits across three pages in landscape mode.
|Our image now fits across three pages in landscape mode. But depending on what printer and paper you have, you could do better. For example, if your printer can print on 11x17 or A3 format paper, it could fit on two pages.|
|But even with an ordinary ink jet printer, if you have legal size paper (8.5 x 14"), you can print on larger sheets. Click on "Configure printer", and select legal size paper. How this window looks varies with what type of printer you have, so I'm not including a full picture of the window for this step.|
|With the paper size now set to "Legal", our armrest now fits on just two sheets of paper.|
If we now select "Print preview" from the print window, we can see how this will
look in a final printout. The lines of the armrest, and the cut off 23 3/4"
will make it relatively easy to paste the two pieces of paper together once
it's printed out. But to help align pages, you might want to turn on
the grid overlays - see below.
Let's close that print preview window, close the print window, and select "Undo crop" from the "Image" menu to get back to the full image of the rocking char.
We are now back to our full image, but laid out on legal (11x14") paper in landscape mode.
|We can select grids to be superimposed on top of the images. The diagonal grid is particularly useful for aligning sheets of paper to each other.|
With the diagonal grid turned on, a continuous diagonal grid of thin lines is drawn on top of the image across all pages.
The square grid is most useful as a reference, and for checking that your printout is accurate. In general, even cheap ink jet printers will produce accurate printouts. However, laser printers, even expensive ones, may often produce printouts that are as much as 1% scaled in one direction or the other, so it may be useful to check and calibrate the printer scale.
When pasting the sheets of the printout together, make sure that both directions
of the grid lines line up is sufficient to ensure alignment in both directions.
A square-only grid is only useful for aligning in one direction, but if
the diagonal lines are continuous as well, you will have perfect alignment along both axes.
|You can also customize the size of the grid, whether the grid is aligned to the image of the pages, and what size the grid is using the "customize" option under the "grid" menu. The main window display will always update to whatever grid adjustments you make, so it's best to familiarize yourself with the options in that window by playing around with it.|
|Let's open that image in BigPrint. We want the scale length to be 64 cm (25 inches), so we mark that distance and specify it as 64 cm (or we could specify 25 inches) With the image cropped to just the guitar itself, it fits on just 8 pages with the paper oriented horizontally.|
But that's a very large area of blue, and ink jet printer
cartridges are not cheap. So it really doesn't serve our purposes to be printing all
that blue. This is a fairly clean image, so let's try the ink saver on it.
As you can see, the solid blue areas are now faded in the middle, but we still have all the edges for tracing the pattern.
Lets switch to "Custom" ink saver mode.
Now, by adjusting edge detection to the fewest possible edges - and only showing narrow areas around the edges, we can really cut down on how much ink will be needed. Adjusting the brightness also helps to save ink.
We lost the strings, pickups, and knobs; but if we just want to print out a template of the body, this will do just fine.
|For printing, it helps to turn on a diagonal grid to help line up the pages. Then it's just a matter of printing, lining up the pages, and using just a bit of glue to stick them together.|
Black and white laser printers, however, have no need to align colors. So laser printers, even expensive ones, often produce images that are half a percent or more off in scale.
The best way to calibrate your print scale is to print a test grid. Be sure that both print scales at the bottom of the print setup window are set to 100% before printing a test grid. Using the Grid menu, turn on the Horiz/Vert grid. Also go into "Customize" from the Grid menu, and select "Grid extends past image", and a grid spacing of 2 cm. You can print a blank page with a grid even without loading an image into BigPrint. Next, print the grid.
Use a metal ruler or tape measure to check the distance between ten grid lines, both horizontally across the page and vertically down the page. If this measure is exactly 20 cm, then you don't need to calibrate the scale. (For clarity, I'm only measuring across 10 cm in the above image).
Supposing you measure the 20 cm interval to be 20.1 cm. This means that your printer is printing at 20.1/20 scale, which divides out to 1.005, or 100.5%.
So we need to scale the output from BigPrint in the opposite direction to compensate, so we divide 20 by 20.1. So basically:
|Print scale =||× 100%|
Where "Your measurement" is what you measured for what should be 20 cm. For 20.1, we take 20/20.1 x 100 = 99.5%
Be sure to do this both horizontally and vertically, because your printer may be scaling differently in each direction.
This scaling will now apply to all printing on that paper size. The grid will also be scaled (that's why it's important to have both scales at 100% before printing a grid for calibration)
If you change the paper orientation, BigPrint will automatically swap the values. You will notice that the labels for the two numbers "Height" and Width" swap when you switch between portrait and landscape paper orientation.
If you plan on printing with different sizes of paper, you might as well select those sizes of paper and enter the scale factor for those numbers. BigPrint will remember the scale factors across several printer and paper combinations, and when you switch back to a known combination, the numbers you entered will reappear.
If you are using a large laser printer, be sure to swap the width and height values for 11x17 or A3 paper, as this paper typically feeds lengthwise, whereas normal letter or A5 paper will typically feed through the printer sideways.
Cad export to BigPrint