Intentionally inflicting a 4" hole in the deck

[zAr]

So I'd like to add a Dickinson solid fuel furnace to my boat and also some vents.

I've read Maine Sail's page on rebedding deck hardware and will use some of those techniques (thank you Maine).

Are there any how-to articles out there for adding a 3-4 inch hole to the deck, such as:

1) keeping the hole straight and level despite the slope of the deck,
2) what tools to use for drilling the hole,
3) how to make a wooden exhaust fitting match the deck slope

I'm thinking of making the hole, removing some of the core, inserting a waxed wooden plug, making several smaller surface holes around the larger one to inject epoxy, removing the plug when cured, then reusing the smaller (now filled) holes for screwing the wooden exhaust fitting to the deck. That's the theory anyway...

Any advice or links greatly appreciated.

[JohnRPollard]

Probably the best piece of advice I can give:

After drilling your pilot hole for the hole saw, mount the hole saw in your drill and then begin "the cut" with the drill in reverse. This will give the hole saw a chance to cut gently into the deck gelcoat initially, without grabbing and tearing at it.

After you've made it through the gelcoat with the drill in reverse, you can switch it over to forward and begin cutting into the fibreglass a bit more aggressively.

I had a helper hold a roughly 6"x6" piece of 3/4" plywood held in place under the deck, to give the hole saw something to bite into as it came through the deck. This helped to keep the cut clean belowdecks too.


Just curious about your choice of the solid fuel Dickinson. When I spoke with them about this option (which interested me), they told me they did not recommend the solid fuel stove for serious heating, only for ambiance. We opted for the Dickinson propane unit, for a number of reasons.

Here are some posts where a bunch of us have discussed pros and cons of various fuel sources, and I think you'll find some installation tips among the discussion too (particularly MC1's thread regarding the temporary closing of the chimney):

Wood, Diesel, or Propane Heater?

Cabin Heater Type and Arrangment

Temp Closing Off Chimney Holes

[sailingdog]

You won't be able to keep the hole vertical very easily. If that is absolutely key, then you'll need to make a jig of some sort to manage that.

A variable diameter hole saw is a pretty simple device to come buy and not too expensive. Basically, it has two cutting arms on a marked bar that has a center spindle. By setting the two cutting arms at the right distance, you get a hole of pretty much any diameter you need.

You'll also want to use a router, laminate trimmer or dremel rotary tool to clear out the core material and then pot the entire edge of the hole, as well as the fastener holes for the exhaust pipe.

JRP's advice about running the drill in reverse and protecting the gel coat is a good one. However, unless you're cutting the hole perpendicular to the deck, it won't help you much. Taping over the area you'll be cutting through will help a bit.

If you're living aboard, I'd go with either the propane or diesel fueled version of the stove, rather than a solid fuel version, as JRP suggests. Solid fuel is really far less convenient.

[pdqaltair]

Originally Posted by zAr

So I'd like to add a Dickinson solid fuel furnace to my boat and also some vents.

I've read Maine Sail's page on rebedding deck hardware and will use some of those techniques (thank you Maine).

Are there any how-to articles out there for adding a 3-4 inch hole to the deck, such as:

1) keeping the hole straight and level despite the slope of the deck,
2) what tools to use for drilling the hole,
3) how to make a wooden exhaust fitting match the deck slope

I'm thinking of making the hole, removing some of the core, inserting a waxed wooden plug, making several smaller surface holes around the larger one to inject epoxy, removing the plug when cured, then reusing the smaller (now filled) holes for screwing the wooden exhaust fitting to the deck. That's the theory anyway...

Any advice or links greatly appreciated.

I have installed the gas heater; there may be some differences.

Sail Delmarva: Let There be Heat!

Why get the pipe vertical? Match the slope of the deck. That is what the instructions indicated for mine. What is more important is making sure it is out of foot traffic and will not snag sheets. IF it was important to me, I would cast a FRP block to the deck that was horizontal before I started. Then everything is simple.

Hole saw works well. Didn't have a bit of trouble. If you chip the gel coat a fraction it won't matter because there is a large ferral on both sides... at least in my case. But it didn't chip.

You will need to remove some core, but all of the fancy dancing is not needed; simply thicken the epoxy and work it into the space with your gloved finger. Quite neat, if you start with the right viscosity.

I will suggest propane or oil. I can't imagine wanting to fool with solid fuel and hot ashes in a boat. They are quite safe if the installation is to code and careful.

[mitiempo]

The waxed wooden plug isn't needed. If the epoxy is mixed to the right consistency and not runny it is easy to put in the gap with a putty knife or gloved finger. Here are pics showing this during my recent hatch installation.

[brak]

Originally Posted by mitiempo

The waxed wooden plug isn't needed. If the epoxy is mixed to the right consistency and not runny it is easy to put in the gap with a putty knife or gloved finger. Here are pics showing this during my recent hatch installation.

Second that. I just (re)installed a vent this way (after it's been installed by PO who covered the open edge of core with *silicone* ). Interestingly, core around the main cutout was more or less ok (though quite soft, but that's balsa) but small holes for fasteners were leaking like hell, evidently.

For many projects like these getting deck cut-out just right isn't critical. All you need is to make sure that the pipe can go through. There is usually some sort of a trim piece/cover etc. that goes around the hole and makes it look all neat and clean (yes, I know, hiding things is no fair, but it helps).

[LookingForCruiser]

Originally Posted by sailingdog

A variable diameter hole saw is a pretty simple device to come buy and not too expensive. Basically, it has two cutting arms on a marked bar that has a center spindle. By setting the two cutting arms at the right distance, you get a hole of pretty much any diameter you need.

The variable diameter hole saws are a lot bouncier than the fixed-width kind. I much prefer a fixed-width hole saw after using both.

[zAr]

Lots of great and helpful feedback here, thank you everyone!

Many of you asked why I'm going with the solid fuel instead of propane or diesel. I did put a lot of thought into this and only recently made the decision. I'm living aboard on the water in Toronto (my second winter here) and the furnace is mainly in case of power failure. The solid fuel burner doesn't need any electrical input. If the power goes for a few days I can just make do with the furnace plus a small generator for the ice eater and various bulbs. My first priority will be keeping all the indoor plumbing from freezing - remember, it's not winterized but the engine will be, so engine as generator is out.

But yes, ambience was a big factor, the lovely smell of burning wood.

Also, merely running my propane stove seems to steam up the portlights and hatches. More moisture from the burning "wet" fuel is the last thing I need in winter and dry heat will dry my gear quickly.

But I also like to start simple and work my way up the complication (and expense) ladder - if solid fuel doesn't work, I'll start thinking about a different unit, plumbing into existing tanks, etc.

A big downside is I really really don't like having to put a 4" hole in my deck. On the plus side, I can reuse it for a vent if the furnace idea doesn't work out. But geeez.

I'll let everyone know how it goes!

[pdqaltair]

Yeah, cutting a 4" hole is tramatic. I sailed a whole summer with a cardboard box taped to the bulkhead before I settled on a heater location. I know where your coming from.

A properly vented propane stove like the newer double-pipe version I use does not add ANY moisture to the cabin. The older Cozy Cabin model was known to get things damp (the stack was too small). The double pipe heater is also far more fuel efficient.

Burning wood in a marina can be a problem. Many forbid it outright, since boats are close together and stacks are short; your nice smell could be blowing right into your neibor and be very objectionable and infact, unhealthy. Also, if ash lands on a nice deck, you can be in real hot water. One sailor at my last marina was requested by managment not to use it.

Gas and oil heaters only require the smallest amount of 12v power, to run small fans, valves and sometimes pumps. No more than a light or 2. But yes, even the "no power" propane heaters have to power a gas solenoid. The generator will do well.

[rikhall]

We too went with the propane version and really like it. Did the "vertical" cut and made a wood block to compansate for the curve of the hull. A few pictures here:

http://irwincitation34.wikispaces.com/Fireplace

It was so nice on the cool mornings to fire it up while I made the coffee. The Commodore then got out of bed to a warm cabin and a hot cup of espresso.

I'm sitting in an airport on my way home, but if you need more pics, send me a PM

Rik