Bending a pig's ear

[John Rumm]

Any suggestions for bending a section of pig's ear handrail?

I would like to gracefuly curve the rail when it reaches the winders on a staircase. This would require a downward bend at the top and an upward one at the bottom so as to follow the tread line at a constant height from it.

If it were a rectangular bit of wood then I would probably try steaming it for a bit, and then bending it into a former of some description, but this is a quite heavy weight softwood moulding and the bend needs to be at about 45 degrees to the long axis of the profile which makes the whole task sound a tad more tricky!

The cross section is a bit like: __ / \_ \_ | \ | | | \|

-- Cheers,

John.

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[The Natural Philosopher]

Hot ammonia is the thing. You can bend some woods into radii only a few times their cross section.

But the ammonia needs a long time to penetrate.

[Rob Morley]

How about splitting it and laminating it into a curve?

[John Rumm]

Hmmm, I had not thought of that... What would be the best way to split it in a controllable way?

It does give me another idea though...

Two bits of handrail, cut one into laminairs on a table saw so that each slice is the same thickness as the blade kerf. Now repeat with the second bit but offset by a blades thickness. This should create a set of fingers that ought to interlock:

____________ ___________________________ |_____________ |___________ _________________________| ____________| |_____________ |___________ _________________________| ____________| |_____________ |___________ _________________________| ____________| |_____________ |____________ _________________________| |______________

In fact the short bit need not even have any unsawn bit - i.e. just use it as packing slices to replace the wood taken out by the bade kerf. I could then glue it up, bend it and finally trim the end square...

[Andy Dingley]

You'll not do it by bending.

Brick-stack a suitable blank, taking care to route the grain in suitable directions for the finished result , Then bandsaw it to shape (or coping saw, with plenty of tea breaks) and spokeshave it to finish. It usually needs a home-made scratch stock to do the final shaping.

[Rob Morley]

That was the sort of thing I had in mind - you shouldn't need to cut the slices so thin if you steam it, then just glue in thin packing pieces and trim it up. How much scrap have you got to experiment with? :-)

[John Rumm]

I have a 4.8 and a 2m bit. I need a 3.3 long run, plus about a meter top and bottom. So I can probably afford a small bit to practice on.