Details Associates Roundhouse Smoke Vents

Model Railroader Layouts and layout building
1

As I slowly apply the roof shingles, I have given some thought to the smoke vents. There are 3, one for each stall and there are several styrenbe parts to each vent.

Imagine upside down cone that supports a pipe and on top the pipe is a top and a little cap above that. The pipe extends through the cone and down into the roof and there is a little nubbin that glues onto the bottom. Straight forward, except…

My problem is if I assemble it as it is molded it is going to be perpendicular to the sloping roof and the pipes will be a strange angle and not vertical.

  • I could trim the base of the cone,but that would be hard to get the correct angle and the same angle on all 3 cones.
  • I could oval out the holes for the pipe so the cones would mount perpendicular to the roof but the pipe would sit vertically. Still might look a little weird and the pipes may be unstable
  • If I have a wood dowel of the appropriate size, I could cut it into a wedge so the cone and pipe sit perpendicular to the ground.
  • One of you has a better solution.
2

Hi, Henry

What I’m missing is — what does the opening in your roof look like?

I imagine that If I were doing the same project I would assemble the complete smokejack, make a block of wood to the exact interior height that I want the bottom of the funnel to maintain, which would keep it parallel to the floor as the cement sets.

Then the round stack would protrude through your roof opening and you could cement this in place, before shingles are applied.

Once the cement sets, I would form flashing from styrene or brass shim stock and apply it like real flashing would be applied.

Then bring the shingles up to the flashing. The trailing (downside) of the flashing would overlap the shingles.

Roundhouse by Edmund, on Flickr

Roundhouse-jack by Edmund, on Flickr

Does that help or confuse the issue?

Cheers, Ed

3

Ed’s drawings gives good information.

For the prototype, the hole would be cut so the pipe goes through vertical, and then the “boot” (the cone thingy) would go over it, and that would be fastened to the roof.

Those boots, commercially, can be bought to fit the pitch of the roof. As a model, you’ll probably have to fashion the bottom of the boot to fit the roof pitch, and glue a flat square peice of thin styrene to the bottom of the boot, as the flashing.

You would run the shingles up to the stack, then install the boot, with the base you added, over the top of the shingles. As you run the shingles around the stack, the shingles “up hill” from the stack, would cover the boot base, as that boot, and the flat piece you added, is the flashing.

That would follow the way the prototype would be done.

Regardless how you do it, or add the flashing, the flashing down hill from the stack would go over the shingles, and on the up hill side, the shingles go over the flashing.

[*-)] Yea, I know, I hope I explained it so you get it.

Any decent pictures I can find that show what I explained, are all under copyright. [sigh]

Mike.

4

I guess I better take my own advice from another thread and read the manual [:S]

I’ll get back to you on this, and maybe take some pictures.

5

To get the exhaust stacks perpendicular to the ground, rather than to the sloped roof, a useful tool is a carpenter’s variable-angle square

To position mine on my Korber roundhouse, I drilled up, through the opening in the top of the smoke-collector hoods, then used the variable square to set the stacks plumb to the ground…

Wayne

6

A carpernters variable square, cool…a new tool to buy!

I had the order of the parts all wrong. The large smoke jack does go inside the roundhouse as suggested above. The part at the roof, I thought went near the top of the stack.

The roof is a heavy cardboard with a really huge hole, relative to the diameter of the chimney. I decided to shingle across the hole, thinking that I could cut a hole for the chimney afterwards.

Now, I’m not sure I can do that neatly. I might cut a square of styrene, drill an eliptical hole in that and glue that to the roof. That will give me something solid to glue to the chimney.