This will show you how to build a cool fancy steampunk blunderbuss rifle.
(for the grunge people...its fancy, it's victorian, ...just deal with it).

Step 1: Materials and Stuff

Generally it is good to overbuy on everything so you can make some choices.
Nothing in this tutorial is essential, feel free to experiment. I did. Go raid the thrift stores for all the brass you can find.

brass stuff (chandelier, lamp, candlestick, bucket, towel rack supports, coathook, screws, nuts, bolts)
wooden banister
table leg
1/4" wooden doweling
gorilla glue or equivalent
snowpants
railing
spraypaint (gold, copper)
brown stain
jigsaw or equivalent
drill
tinsnips
screwdrivers,hammer, needle nose pliers, metal file, vice grips, punch (+ random regular tools to suit)
gloves
old phonebook or large chunk of wood

Step 2: Paint the Banister Gold/brass

Find a nice wooden banister rail and cut it off to the shape you want, and sand it and spraypaint it gold/brass.

I made several of these and the non-oak ones look best because there is no grain, a softwood is smoother.

Step 3: Supports for the Boiler

I had a bag of old bathroom parts including several towel rack supports. The supports are two pieces with a screw holding them together on the bottom. This was handy.
They have a plate on the bottom of them to affix to the wall invisibly, and then the support goes on held by a tiny set-screw. I sort of came up with what the whole structure would be sitting and marked the spots and mounted the plates.

Step 4: The Candlestick

Brass candlesticks generally come apart being supported by a threaded shaft on the inside holding the cylindrical parts together with a nut on the end. I took this one apart and with the extra "give" in the threads put a hole in the support to put the shaft through and re-assembled it.

Step 5: The Boiler Other Half

I repeated the basic part from the candlestick with the brass bucket that looked neat and matched the size of the end of the candlestick.

I drilled a hole in the end of the bucket, a hole in the support and mounted it with some washers a bit of a threaded rod from the chandelier, the same as the candlestick. I left some threaded rod showing out the back to put the fancy swirl finial later.

The two supports and their brass parts can be actually mounted on the shaft of the gun later, since they were fragile, but the setscrew let them be easily dismounted and stored while I did the other work.

Step 6: The Butt

The barrel of the gun needed a butt. This was made from a table leg that seemed to be the right shape. I stained it darker and drilled it, put in a couple of dowels and using some brass tinplate brackets, screwed in some extra support before I glued the dowels.

I put the "hard to screw in" part of the bracket (screw #1) before gluing, think about angles while assembling stuff.

It holds quite well.
I used Gorilla glue, which foams after an hour or so, and you have to wipe off, but it makes up for the messiness of my drilling. (Always use small drills and then a few larger sizes when drilling oak or metal).

The tinplate things were very small so I held them with vicegrips while drilling into an old phonebook (to protect the finish). I work outside on a cinderblock because I don't have a workshop, the cinderblock and phonebook work well for supports.

(drill then holes for the butt finial from step 12 now too)

Step 7: The Trigger

I used a swirl from the chandelier and an old coathook to make up the trigger. I cut the swirl off and mounted it like the butt, using its existing threaded rod, and a wooden dowel and glue. The coathook, I just screwed in after drilling pilot holes.

Make sure you can hold it properly for placement before drilling (and mount it facing the right way...doh).

Step 8: The Blunderbuss

The flared end was from an old lamp bottom (2 pieces) and another towel rack support.

The lamp I took apart, reasembled the base inverted, and used the towel support to look raygun cool.

There is a shaft from the lamp glued into a hole I drilled into the barrel. I had to actually screw the towel rack support onto the flared end so I had to drill some holes in it. (A punch to start the hole really helps here so you don't mess up the brass on the round surface).

The shaft was mounted with a nut under the base of the towel holder so you can's see it. The towel rack support upper piece holds on the cup. (it's easier than it sounds.)

[shaft, lamp bottom plate, nut, rack support bottom plate, cup, rack support upper knob]

I also spray painted the inside a nice metallic copper since it looked crappy.

Step 9: The Tubing and Swirls

The tubing and swirls were from a brass chandelier I found cheap. It had 12 arms on it so I had lots of swirls and tubing and electrical hardware nuts and threads to use (easy to buy more though, you have to get them at the electrical part of the hardware store, for some reason the wood section nuts and bolts all have different styles of threads, luckily the electrical department standardized their sizes)

The wire comes out of the tubing much easier if the tube is straighter, and don't try to twist it.

Disassemble the chandelier except the swirl part.

You can bend the tubing by hand without folding it if you are careful. I proper machine would have been nice.

I used a railing outside covered with snowpants to pad it. Any thick fabric would work though but they were just inside the door).

To bend, put the tube at the beginning and bend a little over the rail. Move down an inch and bend slightly. Repeat bending only about 10% per time every inch, until you get what you want, REALLY SLOWLY or the tube will fold and crease and look like crap. (I got better on the second one). The tighter the bend the less far down the tube you should bend each time.

This will be the hardest part not to screw up. (buy a chandelier with lots of arms...)

Step 10: Mounting the Swirls

The swirl looked great as a gunsight and conveniently fit right into the hole where the electrical cord was in the bottom of the lamp base. I just used the existing thread from the arm attachment and bolted it right on with a nut.

The swirl looked good at the back too as a finial so with the threading I left on the boiler brass support, I put one there too the same way.

So now you have two swirls with tubes sticking out of them. I had a fancy double ended connector to put the tubes together but the tubes were short. I had a third piece cut from the trigger, but it only had threads on one end.

Step 11: Adding Threads (gah)

A threading machine would solve your problem here but I didn't have one.

I had an inch of threaded tube though which a wanted to glue on.

I tried with a stick inside (lazy right?)
That broke off when attaching the tubes

I used a proper dowel...it broke.

I used a large bolt, glued it inside. It held.

(Use steel not wood.)

I had never used gorilla glue before, it holds metal, wood, steel, but it is slow and you can't get it off of your hands. so wear gloves, or you will have BLACK HANDS LIKE A DIRTY PERSON, for several days.
It stains you.

Step 12: The Butt Flourish

The butt of the gun needed something since I couldn't router it smooth or anything so I went with the finial from some sort of cupboard doorhandle pull. I cut off the end of the thing so it wasn't sticking out above the butt.

It actually took some looking to find a finial that mounts a the top not the ends. Most big ones were longer than the butt end. Looks good though.

I put in some screws into the holes of the doorpull and left them sticking out of the for more grip then drilled holes into the butt and glued it on.

(this would have been smart to think of in step 5, but why should your life be easier than mine?)

Step 13: Alternate Ending

I only had 4 towel rack supports and wanted to make an identical rifle, so I had to make due with what I had. An alternative boiler design used the second of the pair of candlesticks, and just the burner of a cheap oil lamp with the glass chimney supports just folded over the end to hold it on.

It looks good too.

The tubing couldn't end the same then, so I just drilled a hole in the banister and mounted some extra threaded finials on the other side. (This design turns out to be more practical actually, since the gun is easier to set down without the tubing in the way.)

Remember when you are building and designing to hold the gun in the way you would when it is done, and you will see any design flaws like sharp objects sticking into your belly. Make sure there is room for you hands on the end of the barrel and the tubing is not in the way etc.

Good luck.