Hello MMDers -- I thought I would throw in a few thoughts on this
little subject we have going here, having built and restored many organ
pipes.

In my opinion MDF would not be a good material for organ pipes, other
than the possibility of the sides and backs of bass pipes, because you
are most likely going to get dull dark sounding pipes.  Many have
stated that the wood type and its resonance has nothing to do with how
the pipe sounds.  This can be no farther from the truth!

The type of wood, its thickness and even the finish, shellac, lacquer
or varnish, all effect the pipes sound.  The pipes do resonate -- why
do you think that the most valuable orchestral Violins are made of
spruce and not walnut, and the same question with piano soundboards?
It's the resonate quality in the wood and its properties.

It has been also mentioned that church pipe organ pipes are all metal,
a "lead and tin" combination.  This is also true, but different types
of pipes are made with different ratios in the pipe metal.  It's not
all just a standard lead and tin combination.  Pipes with a greater
lead content tend to sound dull and dark; the pipe metal is thick.
Pipes made with a greater content of tin tend to have a much brighter
sound, such as in the string and principal ranks; the metal here is
thinner and it does resonate.

Now there is a whole separate subject here about pipe building and
dimensional ratios that effect the sound but I will leave this for
another time as we are talking about wood here.

The master builders have always used wood for their pipes, and you
should follow suit.  You need to search out a good commercial lumber
yard that can supply you with good grade pine or even poplar, and
hopefully some maple also.  Some even have onsite mills that will plane
the material for you, but a good home workshop Delta planner can be had
for around $300 and will pay for itself quickly, especially when you
need just one more little piece of something.  Avoid the "do it
yourself" clubs as this lumber is a very poor grade and is best left
to building crates!

You will find that it does not cost you that much and you will be much
happier with its results in the long run.  Poplar is used quite a bit
in the organ industry, and when last checked, Don Stinson of Stinson
Band Organ Co. was making most of his pipes from this material.  It is
a good material, dry, and it machines well and is less likely to split
or check on you.

In the words of Mark Wicks, from the book Organ Building for Amateurs,
"Let your workmanship and materials be as if your life depended on it".
So in other words, use good materials and do everything the way you
want it the first time.  Also, George Audsley's book, The Art of Organ
Building, has a complete chapter on nothing but what we are discussing
here: all types of woods and what they are best suited for.

I did not mean to start a novel here, but this is very important stuff
to people who build organs!

Thomas Grace
Chino, California