Cutting Dormers: part 2

photo copyright Karin Corbin 2012

Cutting dormers for the Elizabethan birdhouse part 2.

This time I am using the same miter slot sled jig I made in part 1  to cut a dormer for the back of my structure and also  the two side gable  ends. These pieces are triangular without any vertical side lengths. I have changed the angle of my miter fence using the 60 degree drafting triangle and now the base of the triangle will rest against the fence unlike in part 1 where the vertical sides were resting against the fence.

photo copyright Karin Corbin 2012

The first step was to cut a piece of material to the width of the base of the triangle given in  my measured drawing.

photo copyright Karin Corbin 2012

photo copyright Karin Corbin 2012

The right side of my jig was cut off by the saw blade so that is an easy indicator of where the actual cutting line is and I will make use of it as the registration for the point of my triangle. All I have to do is place a scrap piece of plywood at the corner where the fence and that right side of the jig intersect. Then I butt the material I am using for the dormer over to that location, remove the scrap and while holding the material down on the jig against the fence I slide it on through the saw blade to make the first cut. I always turn off the saw motor and let it come to a full stop before removing the part from the jig or trying to remove the waste cutoff piece.

photo copyright Karin Corbin 2012

Now flip your material over, register it again to that same intersection as in the last step (don't forget to remove that scrap you used to located the corner of the triangle) and then cut the last side of the triangle. The peak of your triangle will be perfectly centered across the width and that means it will also be the correct height. This is a very simple method once you get the hang of making triangles this way on your table saw. But if you are going to do lots of them exactly the same size for a production type of product then use a stop block on the left end of the fence instead of registering your pieces it to the corner each time.

photo copyright Karin Corbin 2012

I will do a post on making the roof cuts for the dormers later, it involves making compound cuts, a bit more complicated as you have to make a left and a right side but  it is  also done with a miter slot jig.

Elizabethan birdhouse

Cutting dormers part 1

Cutting Dormers: part 1

photo copyright Karin Corbin 2012

Cutting dormers for the Elizabethan birdhouse part 1

I still remember the days when I did not know how to approach making things like dormers for a miniature building. Lack of knowledge and often a lack of tools is where we all begin. This being a teaching blog I will show you how I am cutting the pieces for the front of a dormer that has a steep roof pitch. There are a number of methods to make these cuts and I don't always make them this way.

The miter angle fixtures that come with table saws won't rotate past 45 degrees but for this house I have to cut a sharper angle than 45. The method I chose  is to make a single runner miter sled for my 10 inch table saw. I have a number of pieces to make using this particular angle so the jig will be useful for insuring all the parts get cut to that same exact angle without variation.

photo copyright Karin Corbin 2012

The runner that goes in the table slot could be made of hardwood or if it is only going to be used a few times pine or basswood will also do the trick.  I am using a metal slide since I have one that I can unscrew and use it again and again for other jigs if I wish. As you will see I am using materials out of my scrap bin for the sled base and for the fence as well. Actually the plywood came out of a neighbor's scrap bin, I am not too proud to use his leftovers!

photo copyright Karin Corbin 2012

As I am cutting this roof at a 60 degree angle I am using a  drafting triangle with a matching angle to accurately establish the angle. I place the edge of the triangle right against the saw blade being sure it is not resting on any of the saw teeth, sneaking it between them, touching only on the flat of the saw blade. I have attached the fence to the base with double back carpet tape, it is plenty strong enough to hold it in place without shifting. I am using double back tape because I am going to reposition that fence to a couple of other angles for other dormers and gables and dormer roofs before I am done with all the cutting on this structure.

This first dormer front wall I am cutting has some vertical sides on it. Other dormers and gables I will cut are simply triangles with no vertical sides on them. I am showing those in other postings.

photo copyright Karin Corbin 2012

First the dormer plywood material is cut to width. Then I mark out how tall the vertical sides are. I make sure the mark at the point where the roof pitch starts gets transferred on down the edge of the plywood. That mark is going to be aligned with the cut edge of my miter jig. See photo above, it will enlarge if you click on it. This is a quick, simple and accurate method of aligning the starting point of the cut for the sloped roof line on the dormer.

photo copyright Karin Corbin 2012

The first cut goes just past the point of the peak.

photo copyright Karin Corbin 2012

Then the board is flipped, aligned to the mark and the second cut is made.

photo copyright Karin Corbin 2012

Notice how my board is left longer than the length of the small dormer, it gives me good registration against the fence. I will cut the second dormer piece I need from the other end of the board. That butterfly shaped piece left in the middle will still be there for a nice long registration against the fence.

That center waste piece has complimentary angles that will soon be recycled into making yet another miter sled jig for cutting the timber frame trim pieces that will go onto this dormer and on the gable ends of the house. Be sure to watch for opportunities like this because they give you those exact matches on angle cuts that will fit perfectly onto your house parts. I will show you the jig I make from it later on in this blog.

If I was making a dormer with equal side lengths I could have used a stop block on the fence for the second cut. But these dormers are on each side of another third dormer that sits between them and the peak is not centered across the width of the dormer.  You can see the dormers I just cut on the CAD model in the image below. They are on the left and right of the center dormer. Elizabethan birdhouse image below.

photo and design copyright Karin Corbin 2012

Link to Cutting Dormers: Part 2
Link to Cutting dormers: Part 3