Some of you may have read, or heard of, Ray Bradbury's novel Fahrenheit 451. It concerned a society that burned books, and the title was taken from the ignition point of paper. 451 degrees Fahreneheit.

The wood in your tube should char at pretty close to that temperature. The melting point of aluminum is 100 to 200 degrees above that, so if you can keep your temperature fairly well controlled you should not have a problem.

A shame the tubes are so long. Your kitchen oven probably gets up to 450 or 500 degrees, but those tubes would not fit inside it. Or would they? Take out the shelves in the oven, stick in a dozen tubes and let half the length extend out the partially opened oven door. Set the thermostat to 450 or above and roast those tubes for 20 minutes. Then flip them over and roast the other end.

Pull one out while it is hot (and expanded), and with the hottest end (most expanded end) on a brick, try to drive out the hopefully slightly charred stick. Inside of an hour you should have a dozen cleaned out tubes. Oven mitts should be all the protection you'll need, but htose tubes will stay hot for a while, so have a place to put them as they cool.

A wire-handled bottle brush can be dragged through the emptied pipe to clean out the soot so it doesn't make a continuing mess inside your boat.

Other thoughts on a less invasive process:

WD-40 apply liberally and let it soak in. Then apply some more.
Ether, acetone, denatured alcohol -- You can get a can of ether for starting cars. Spray some in and cap the end you sprayed it in from. The others are liquids which you an just pour in, then cap the end with a plastic bagg and rubberbads, or a cork. Stay away from heat with these! The idea is that a thorough soaking will destroy the glue bond between the wood and the tube, or maybe lubricate the bonding area.

Instead of pounding out the recalcitrant rods, you might try drawing them out. You'll need a 1/4 inch hangerbolt, a length of 1/4 inch threaded rod, some fender washers which will fit over the 1/4 inch bolt, two 1/4 inch nuts, and a threaded coupling used for joining lengths of 1/4 inch threaded rod.

Use an electrician's bit, or an extension and a conventional drillbit to drill a starting hole (7/32nds or 3/16ths) in the end of the dowel. Use the coupling to connect the machine threaded end of the hangerbolt to the length of threaded rod. Drop this into the tube, and start to screw it into the wood. Drop two fender washers over the free end of the threaded rod and spin on a pir of nuts. The two nuts, jammed together on the threaded rod will allow you to grip one with a wrench and continue tightening the hangerbolt. Get it in solid. Then separate the nuts and spin one down to rest on the fenderwashers.

Tightening this nut will cause it to rotate on the fenderwashers like bearings, and pull up the dowel like a cork out of a wine bottle. IF it is free enough to be drawen out.

With this arrangement in a tube you can pretension it and see if the dowel loosens with the application of heat from a heat gun or propane torch.

Or, you can bolt a come-along to the threaded rod sticking out of the tube and put some REAL force on it.

: I'm going to try heating it on the BBQ tonight. The BBQ is cast
: aluminum...thought being that it won't get hot enough to deform or melt
: the tubing. If it doesn't work, I'll probably ream out the dowel enough to
: get a ferrule inside.

What would you need a ferrule for? You already have those great wooden dowels inside your tubes. Make use of them. cut the end off of one of the tubes so that you have about 6 inches from the end ofthe tube to the beginning of the embedded wooden dowel. Cut the next tube so you remove the aluminun tube enough that you expose 6 inches of the embedded dowel. Slide those two pieces together. Instant ferrule!

Hope this helps. Oh, and happy grilling.

PGJ