Steve Lewin asked, "Has anyone made wood pipes using MDF board?"

We have considered it, but so far we haven't found it practical.
We use MDF extensively for electro-pneumatic chest parts: pouch boards,
magnet boards, and any action channels.  In pipe organs, the action
parts made of MDF do not need to be dipped in shellac to seal them.
For the tighter requirements of player pianos this probably would not
be the case.

> What would be the best sealer to use on this board material?

For appearance, shellac is very nice.  Waterborne finishes tend to
raise the fibers.  MDF also paints well

> Most of the new lumber available these days is not very good quality
> unless you want to spend big bucks.  If you spend more, or a lot of
> money on wood for the pipes, then the finished band organ price goes
> way up.

We have found that for mechanical musical instruments, the cost of
material is a very small fraction of the cost of the pipes.  A 2' flute
or 2' violin takes only about 10 board feet of material for a set of
pipes.  Even at $5 per board foot, that's only $50.  It's the labor
that costs, and small pipes can be cut in very efficiently from solid
woods.  The other issue is that in reproductions, original materials
are always preferred by collectors.

> I was thinking of laminating hardwood to MDF to be used on the
> speaking edges of the pipes.  The rest of the pipe would be medium
> density fiberboard to cut back cost and also to have a very stable
> material if coated in a sealer material.

This is only practical for large pipes, e.g., longer than three or four
feet.  Otherwise any savings are more than eaten up by increased labor
costs.  MDF edges do not hold up, so lips, caps, and flues have to be
solid wood.  The edges of the pipe bodies would also have to be rounded
over.

> I know the pipes would weigh more using MDF but not enough to add
> that much overall total weight.  I have all the wood working
> equipment to cut MDF, carbide tipped, etc.

Even carbide tools have a very limited life cutting MDF.  We haven't
documented the difference, but my gut feeling is that the useable life
in MDF vs. solid wood is around 1:10.

Robbie commented:

>[ A scientific study commissioned by a Dutch organ builder concluded
>[ that the wall material of an organ pipe has no effect on the tone
>[ as long as it is adequately stiff.  Carl Frei made nice sounding
>[ pipes of cheap box wood for Dutch street organs.  The organ builder
>[ balances the cost of the materials against the ease of construction
>[ and voicing the pipes.  Therefore you might ask, "Why don't
>[ professional organ builders use MDF?"  I hope that an experienced
>[ organ builder will reply to MMD!  ;-)

In a nutshell, solid woods let us produce a better product at a better
price.  Collectors aren't interested, and most of our other customers
haven't been enthusiastic either.  Only on larger pipes would it
possibly make sense, and then the weight issue really becomes a factor.

John M. Nolte
Nolte Organ Building
1643 South 38th Street
Milwaukee, WI 53215