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Press Fit House

Introduction

Today you will be taught how to build a Press Fit house using OpenOffice.org Draw and the Laser Cutter in the Fab Lab.

Once you have OpenOffice.org Draw open, right click on the page area and click “Page” > “Page Setup”. Once the Page Setup window (shown below) opens, make the width of the page 24 inches, and the height of the page 12 inches. 24” x 12” are the dimensions of the laser cutter, so doing this shows you exactly how much room you have to work with.

The Wall

Now, select the Rectangle Draw tool.

Using the Rectangle Draw tool, create a rectangle.

Right click on the rectangle and select “Position and Size”

When the Position and Size window opens, make the rectangle 3 inches wide and 3 inches high, with an X position of 0 inches and a Y position of 1.50 inches (X is the left/right axis, Y controls the up/down axis)

The Front

Now, using the Shape drawing tool, select an Isosceles Triangle

Use the Right Triangle tool and create a triangle. Once the triangle is created, open the Position and Size page and make the triangle 3 inches wide and 1.5 inches high, with X and Y coordinates of 0,

as shown below.

Once you have the triangle placed on top of the square, select both the triangle and square (by holding down shift and clicking on each one or by clicking and dragging over both of them) . Once you have both selected, right click on them, select “Shapes” > “Merge” as shown below.

Now, right click on the object again, open the Position and Size page, and go to the Rotation tab. Make the Rotation Angle 45.00 degrees.

Now, bring the rotated object to 0.00” on Position X and 0.25” on Position Y.

Create a new rectangle. The new rectangle should be 0.25 inches tall and 0.50 inches wide, with

and X position of 0.25” and a Y position of 0.00”.

Select the new rectangle, and copy / paste it (Right click and select copy, then paste, or press ctrl+c to copy and ctrl+v to paste). The copied rectangle should have an X position of 1.25” and a Y position of 0.00”.

Now, select all the objects and merge them so you have 1 single object again. When this is complete, rotate the object back by -45 degrees. Once you have the object upright, copy and paste a second one over it, right click on it and select “Flip” > “Horizontally” as shown below.

Once you have the copied object flipped, merge both objects together so that they look like this:

Now, move the object to X and Y positions 0.00”. Create a new rectangle with a width of 3.5 inches and a height of 0.5 inches. Place this rectangle at 0.00” on the X axis and 2.00” on the Y axis.

Copy and paste the rectangle, and place the newly created one at 0.00” on the X axis and 3.50” on the Y axis.

Select all the objects and merge them all into a single object, (right click > “Shapes” > “Merge”)

The Side

Now we need to make the side of the house. Create a new rectangle that is 4 inches wide and 3 inches tall and place it at X and Y coordinates 0.00”.

Now comes the tricky part. We're going to make the holes for the pressfit tabs to hold in now. The measurements for this part of the process need to be exact, or the house won't fit together when it is fabricated. For the cardboard we will be cutting this house out of, the width of the holes should be 0.14 inches. The height for every single hole will be the same, because we already made all the tabs 0.5 inches high. Create a new rectangle that is 0.14” in width, 0.50” in height, and is at 0.25” on the X axis and 0.50” on the Y axis as shown.

Copy and paste the small rectangle, and place the new one at 1.25” on the Y axis, remaining at 0.25” on the X axis.

Now select both small rectangles and copy and paste them. Move the two new rectangles to 3.75 on the X axis, using the top right corner as the Base Point, as shown in the red circle below. If you do this step incorrectly, the house will not fit together correctly.

The side wall of the house is now complete. Select all the objects that are part of it and move them out of the way.

Now we are going to build the last part of the house, the roof. The dimensions of the roof are 4 inches wide and 2.10 inches high.

As before, create a new rectangle that is 0.5 inches tall and 0.14 inches wide and place it at 0.25” on the X and Y axises.

Copy and paste the rectangle and place the newly created rectangle at 0.25” on the X axis and 1.25” on the Y axis.

Select both smaller rectangles, copy and paste, and bring them to 3.75” on the X axis, using the top right base point as before.

Congratulations! All 3 basic pieces you need for the house are now complete. Now, select each piece and copy paste them, and then arrange them in a tight pattern on the bed as shown below. Now you can add embellishments such as doors and windows, using the shapes tool to place the shape you want cut out and then using right click > “Shapes” > “Subtract” to subtract the shape from the object.

Now all there is left to do is print it out on the laser cutter. Power and speed settings depend on the thickness of the cardboard, but 75% power and 33% speed worked well for me. Make sure the bottom boundary of the page is at least an inch lower than the total height of your project, and make sure the cardboard you are cutting is large enough to cut everything out of.

If you want to later cut this project out of wood or acrylic, all you will need to do is measure the thickness of the material you want to cut it out of and change the width of the small rectangular tabs to the new width.