
Gable Construction

The 2nd garage roof support (gable) is also
constructed of aluminum channel. It is glued and screwed
together. Having the right tools and figuring out the lengths
and angles are the key to construction.


Blueprint to Angles

My house blueprints describe the roof
pitches in rise over run. This roof is symmetrical and has 5 1/2
inches of rise for 12 inches of length (run). In miniature
construction I needed the angle to cut my supports as well as their
lengths. Cosine of an angle of a right triangle is = adjacent
side / hypotenuse. In my calculations, you can see how I arrived
at the angles I needed. You need a table of sines or cosines.


Angles to lengths

I measured my house width and divided
by two for a new adjacent side. I then used the tables to get my
hypotenuse. My house width included wall thickness as well as
overhang for the roof.


Frame pieces

The angles were cut on a new water
cooled variably speed bandsaw. Without this tool I could not
have cut accurate angles such as 25 degrees.


Frame Approximated

Both ends have been cut to very close
tolerances.


End Attachment

It is screwed together with angle
braces and glued together with a strong epoxy.


Bandsaw cutting angle

Slow speed and slow cut.


Bandsaw setup

Corner of my garage


Bandsaw accuracy

One of my pieces was slightly tool
long. I shaved an intact less than 1/32 in thick piece at a 25
degree angle. This is amazing.


Metal Epoxy adhesive

I highly recommend this for metal
welding/glueing.


Polyurethane alternative

These made reasonable joints but were
not as strong as the JB Weld.


Final roof supports

I added two braces to each gable end
which was a piece of 1 x 1/8 aluminum bar stock. I added
longtitudinal braces of 3/8 aluminum channel. The whole end is
now extremely rigid.


Angle Bracing

This is the best I could come up with
besides the epoxy. 25 degree angle.


Angle Bracing

This is the best I could come up with
besides the epoxy. 65 degree angle.


Aluminum Welding

Aluminum can be welded/brazed if you
use a special welding rod and work at it. You heat up the
aluminum (not the solder) with a propane/mapp torch while brushing the
surface with a stainless steel brush. No brushing = no adhesion.


Welded joint

The two joints when adequate welded
form a joint that is stronger than the original aluminum. That
is so. I could not break the right angle T joint no matter how
hard I twisted. The center end to end joint is epoxied.


Excess solder

Mechanically, it was easy for me to
leave solder sludge on the aluminum as heating and getting a weld is
trick. This is impossible to remove.


Excess heat

It is also possible, if you are not too
skilled, to melt the aluminum channel. So I opted to only weld
where necessary. My joints could not be brushed and held in
place for soldering but I might use this technique elsewhere in my
miniature house.
