Introduction: Make a Birdhouse Using the Laser Cutter
I joined the TechShop a couple years ago. I was pretty excited to learn AutoCAD, although I found that I do better with a course to thoroughly learn the material. Knowing AutoCAD has been indispensable to being able to use the CNC (computer numerical control) equipment, such as the ShopBot, waterjet cutter, plasma cutter, and the laser cutter. It is the laser cutter that made it possible to put together this project so easily and which is the subject of this Instructable.
I came about making birdhouses indirectly. I actually started out with an offer of a friend to build a copper roof over a gate. I did this with SolidWorks, which is a 3D drawing application similar to AutoDesk Inventor. My original interest was in metal, mainly welding. I had learned SolidWorks after taking a class, which was recommended to me by an instructor in a class in making bicycle frames. (I have the bicycle we built in the class and it really rides the best of the several bikes I currently own.)
To get back to my topic, you might wonder why I decided to design a birdhouse. The answer was that it was a way to practice and verify a design of construction of the gate and roof, which has some tricky constructions and angles. The birdhouse also functioned as a model, where I could practice soldering metal, as well as to find what was available for working with sheet metal at the TechShop.
So let’s get with it, this is what we will build: a picture of the finished birdhouse is shown above.
Step 1: Step 1: Creating the Design
The first step was to do the design. To do this, I used SolidWorks to make the 3D model. In the design, there are a number of angles to the sides and roofs, however, except for a ¼” in the front, all of the sides of the birdhouse a flat pieces. These flat pieces can then be put into a 2D design and cut with the laser cutter. These pieces are then taken out and glued together, to create the basic assembly for the birdhouse.
The 3D drawing from SolidWorks is show above, with the various parts labeled.
Step 2: Step 2: Laying Out the Drawing
To begin to make the birdhouse, we will start with a piece of ¼” wood model board. I purchased my board from Home Depot, where they sell poplar or alder boards measuring 5.5 inch x 24 inch. This design takes approximately 1 ½ boards; the boards typically sell for between $4.00 and $7.00 depending on the wood; alder costs more than poplar.
I have made images of these designs. I converted the SolidWorks drawings into DXF files via AutoCAD, which are easily read by Corel Draw to cut the pieces using the Epilog laser cutter. Although AutoCAD is no longer a really premier drawing application, it is my tool of choice to edit DWG and DXF files, which are used by Corel in the laser cutter.
The outlines for the two boards are below: the top board contains the sides and bottom for the main structure for the birdhouse, as well as the sides for the cupola; the lower board contains the sides of the main roof as well as the support stricture for the roof, which also serves to attach it to the main section of the birdhouse.
Step 3: Step 3: Cutting the Parts--Using the Laser Cutter
After the parts are laid out on the respective boards, they will need to be imported to an application for cutting. I use Corel Draw for preparing the drawings for the laser cutter.
I assume that the reader has some familiarity with the Epilog laser cutter as well as Corel Draw, although other cutters might be used as well as other applications such as Adobe Illustrator.
Once the file has been loaded into Corel, for either the main structure or the roof, the files must be prepared. Basically, this amounts to assigning the size: 5.5 inches by 24 inches. Corel is nice as it automatically positions the files and fits them in the print area. Of course, for cutting the parts, all the lines will have to be defined as “hairline”.
Once this is done, the file is ready to print by selecting the print command. However, first you need to insert the 5.5” x 24” board. I place it at the upper left hand corner of the laser cutter tray. This way, if you need to reposition it for some reason, such as the laser didn’t cut all the way through the board, you can reposition the board easily.
You will then be given the laser setup screen. For this, I selected “vector” for cutting, not etching, the wood, and I set the speed, power and frequency to 18, 90, and 500, respectively. Of course, I was using a 60 Watt laser cutter, so the settings might vary with wattage and the opacity of the lens. I set the size of the work to 5.5” x 24” and exited the setup screen to cut the board.
One note is that it might take more than one pass to cut through the wood. If so, just run another pass.
Step 4: Step 4: Putting the Pieces Together
After cutting the parts, we are ready to put them together. To do this, we will use glue, more specifically TiteBond III glue, which is water soluble when wet, but is insoluble after drying, making it a good choice for outside (exterior) projects. Further, it is made with polyvinyl acetate glue, which dries incredibly strongly, even stronger than the wood fibers themselves.
To make the birdhouse, glue the sides and the bottom together only. DO NOT GLUE THE LEDGE YET. The reason for this is that the sides should be finished prior to placing the ledge into the front. In fact, it’s very possible that the ledge piece will be too thick, or rather the wood is too thick, and the surface of the ledge piece might have to be sanded a bit to remove enough material to allow it to fit into the rectangular holes the laser has cut into the front piece.
Step 5: Step 5: Finishing the Sides
After gluing the parts together, you will now have the pieces above. These will include the assembled main structure, the assembled cupola, and the remaining ledge piece. Of course, there still is the roof board, but we’ll work with this next.
For now, the burned sections of the dado joints, can be sanded off all the edges. The most efficient way to do this is with the belt sander.
Note: After the sides are finished, the ledge should be finished also. After all the surfaces are clean of wood that was burned by the laser, the ledge should be glued in the four slots in the front.
Step 6: Step 6: Best Tool for Finishing the Sides: the Belt Sander
The belt sander is not as dangerous as some of the other power equipment in the wood shop, but as with all tools, it demands a certain amount of respect. Do not use gloves when using the belt sander. The sander also works best when the work is supported against the stops, in this case, the bottom, of the sander.
In the picture, the belt sander is shown with a triangular piece of wood up against it. The angle is cut at 51.4 degrees which is about 1/2 of the angle of 102.7 degrees the roof forms with the front and rear sides. Thus the two sides of the roof can be joined together and mate with the angled faces to form the angle of the roof.
However, the belt sander is the best tool for taking down the sides of the birdhouse, such that all the burn marks from the laser cutter can be removed.
It is also possible to smooth out the edges of the cupola, which could not be cut at an angle and jut out after gluing. Sanding these parts will allow the cupola to fit snuggly on the roof.
Step 7: Step 7: Assembling the Roof
As mentioned in Step 6, the roof angle is formed by the front and rear sides. However, there is an insert that is mounted to the two sides of the roof. This insert is made by gluing the five pieces cut in the roof board together to form the piece in the center of the roof in the picture above. The sides of the roof are then sanded as in the picture in Step 6, using the piece of wood cut with the angle of 51.4 degrees. (I have a digital protractor that actually shows this angle, but 51 degrees is more than acceptable.) The assembled roof should appear as in the picture above. The screw will be screwed through the bottom and into the cupola to allow it to be attached to the roof of the main structure below. HOWEVER, BE CAREFUL in drilling this hole for the screw. The instruction for drilling is in Step 8 below.
Step 8: Step 8: Drilling Holes to Mount the Parts
It should be noted that to put the screw in the center of the roof to hole the cupola, the hole should be drilled in the top of the roof, on the ridge. Drilling into this ridge is difficult, and the drill bit will want to run off the side of the roof. There are perhaps a number ways to deal with this, one being to put the roof assembly in a vise or jig, and then use a drill press to come down directly in the center.
However, a quick and easy way to do this is to use a round (rat-tail) file and file the roof exactly in the middle at cross directions to the ridgeline. This will provide a notch in the ridge of the roof where the drill bit can be steadied to drill down into the support underneath and shown in Step 7. The filing procedure is shown above.
Step 9: Step 9: Finishing the Cupola
The cupola still remains to be completed. At this point, only the sides are glued together. The faces of the sides should have been sanded, and the rectangular ends at the top and the bottom should have been trimmed to be flush with the angles of the main roof, as well as the cupola’s roof.
Once the top of the cupola is sanded flush, the cupola roof pieces can be glued into place. The angle where the two pieces join should have first been sanded using the technique described in Step 6.
To attach the cupola to the main roof, it needs something for the large wood screw underneath to be able to attach. Again, there are several ways to do this. One would be to make a small block of wood that would fit the interior of the cupola, and then glue the block into the cupola, providing a surface for the wood screw.
For filling the interior of the cupola, I chose to use some epoxy filler. For those who may not be aware of this material, it is a two part filling material consisting of an epoxy and a hardener. You mix equal parts of each, the epoxy and the hardener, and mix them; I use a paper cup and a popsicle stick. When mixed, I scoop the viscous mixture into the cupola and allow it to harden.
Typically the filler will have set and hardened sufficiently in 10 to 15 minutes. I then just sand it into the shape that I want. The finished cupola is shown above, with the epoxy filler on the right. There is a hole, slightly off-center drilled into the filler for the wood screw, which attaches the cupola to the main roof.
Step 10: Step 10: Putting It All Together
Finally, we are at the last stage of the assembly process. The main section is complete, the main roof is complete and ready to join to the cupola. The last step is to prepare the holes for the two #6 x1/2 inch screws that are put into the top of the front and rear sides about ½ inch down from the apex of the roof. These screws hold it all together.
Finally, a piece of ¼” diameter dowel should be cut and sanded and glued into the small hole above the ledge.
Step 11: Step 11: Finishing Touches
There are a few things that might be done to finish this birdhouse. They are:
1. Painting it: a clear coat might be best. I used a low-VCO polyurethane. Part of this design was to actually make a bird house that a bird would live in. For this aim, the best design would be all natural, but painting the birdhouse protects it from the elements and helps it last. For this, I used paint with very low emissions, or low Volitile Organic Compount or low-VCO paint. Thus a compromise between natural finish and protection against weathering.
2. Adding an eyelet at the top to hang it. However, it could also be attached to a platform and placed on a stick or pole, or in the branch of a tree.
3. A metal roof might be added. For this, I used a brass plated flashing. I was able to use the shears at the TechShop to cut it, and the brake for bending it. To get the last little modifications, seaming pliers are just the tool. Since I use them so infrequently, I checked out a pair from the local tool library, rather than put out the $25 that a pair of seaming pliers would cost. A picture of the seaming pliers and the finished roof are above.
Step 12: The Finished Birdhouse
Above is the finished project.
As follow-up note: if you want to try to cut the parts to make the board and would like drawings, I can email the DXF file. Send request to: email@example.com.