From: M16302@mwvm.mitre.org
Subject: Re: Making a paddle.
Organization: The MITRE Corporation, McLean VA 22102
Date: Mon, 11 Jan 1993 18:59:59 GMT

I have never rejoiced so much in being wrong! It is obviously easy to make a
racket once you know what wood to use, the number and orientation of the plies,
the glue, perhaps the specific physical properties of you particular wood
sample  -- and then a little woodworking equipment like a planers and sanders!
Not to mention a little experience from trial & error!
   I play Chinese penholder also.  I find one Double Happiness 7 ply too big
and heavy although it holds the loop on well.  The other smaller 6 ply
Double Happines is too head light and doesn't hold the loop on the racket very
well.  Can you give me some advice on making something that is more or less in
between the Double Happiness models in weight and balance and has good
"dwell time" for loopers.  Or, would you consider selling me such a racket?
 
 
 n article <1993Jan11.143949.27094@uicc.com>
 
 
Robert B. Shain                              EMAIL: RSHAIN @MITRE.ORG
The MITRE Corporation                        Voice: (703)883-5592
Center for Intellignence & Special Programs  FAX: (703)883-6991
Mailstop W955
7525 Colshire Drive                    "My other computer is a Cray"
McLean, VA. 22102                      "My other car is a bike"
                                       "My other sport is ping pong"
 
 
neidorff@uicc.com (Bob Neidorff) writes:
 
>
>
>Robert Shain recently posted that it is very hard to make a good paddle.
>We can rejoice in hearing that he is wrong.  I hate to be so bold, but
>I have done it.  I made many paddles.  It is easy.  They work well.
>
>Many of my paddles are "Chinese Penhold".  That's what I use.
>
>I made a few "one ply" paddles, although I personally feel that
>one-ply is only good for the "Japanese Penhold" paddle shape.
>
>I started out with a lot of research.  I sent paddles out to a lab
>to study their wood.  I also studied their glues.  The wood in the
>Double Happiness is basswood (latin Tilia).  The prized Hinoki is
>a Japanese cedar (Chamicipress obtusa or something like that which
>means FALSE cypress: it is not cypress.  Don't use cypress).  I
>also looked at other paddles.  Woods tend to be similar light woods
>with high stiffness to weight.  The glue is either a common animal
>glue (Double Happiness) or a urea resin (Japanese paddles).
>
>Now I went to wood reference books to look up the physical constants
>of the woods that others used.  It seems that valuable properties of
>the wood in paddles is low internal friction and high rigidity to
>weight.  (modulus of elasticity to density)  Cedar seems to be a good
>choice there.  Also spruce.  The third parameter that came up in
>discussion was "speed of sound in the wood".  I suspect that this will
>have something to do with feel, but I never learned enough to say.  It
>isn't commonly tabulated.  Funny coincidence: all good "guitar top" and
>"piano soundboard" woods make good paddle woods!
>
>For my first few paddles, I bought a load of scrap guitar tops from
>a guitar supply company.  I planed them flat and laminated three ply
>blades from spruce and cedar.  I glued with "Plastic Resin Glue",
>also called urea formaldehyde.  This is a tan powder which you mix
>with water by weight.  (I did it by teaspoons.  No need to get fancy.)
>Be sure to get fresh glue.  It absorbs water from the air and only
>lasts a year or so on the shelf.
>
>The three ply paddles worked well.  Thicker was faster and heavier,
>as you might guess.  Balance was nice.  For the same weight and
>thickness, my western red cedar paddle was faster than the double
>happiness paddle.  Spruce was comparable.
>
>When I tried to use yellow "Carpenter's Glue", the paddle came out
>mushy.  I never tried contact cement or white glue, but I suspect
>that they won't work well.  I also see some commercial paddles with
>black glue lines.  This glue is either a resourcinol or a melamine
>glue.  I never tried it because the tan glue is cheap, easy to use,
>clean, and works well.
>
>The handle seems to be a key strength issue.  That is where paddles
>flex, and that is their weak spot.  One friend showed me some paddles
>he made, which he reinforced with fiberglass around the "neck".  You
>can experiment with fiberglass used in repairing boats.  They also
>sell a two-part epoxy to hold the cloth down.  Raw fiberglass cloth
>is literally an open cloth like thin, porous burlap.  It needs epoxy
>to stick it to a base.  Epoxy is foul stuff.  Wear gloves, work in
>a well ventilated room, and be sure to use eye protection, just in case.
>
>I just make the wood for the handle a bit longer than normal and glue
>it on well.  I use maple, walnut, or any pretty, strong hardwood for
>handle wood.  Fiberglass is probably great, but I never bothered with it.
>
>I haven't found a cheap source for carbon fiber.  I'd love to try it,
>but it is probably as tough to use as fiberglass.
>
>It was no fun the one time I made a maple paddle.  Slow, heavy,
>bad feel, bad balance.  I guess that my research on woods pointed
>me in the right direction.  Maple has all of the wrong numbers.  Yet
>I had to try, just once.
>
>After I used up the guitar top scraps, I went to the lumber yard.
>You know what works great for one-ply paddles?  Suprise:
>
>Cedar chest "Eastern Red Cedar".  The trick is to find a piece with
>less than a million knots and more than 6" width.  The knots tend
>to be tight, so that they don't interfere with play.  Big knots
>are much worse than small ones.  Knots less than 3/4" (19mm) diameter
>are insignificant: you won't notice them in play.  Cheap.  Easy.
>Light.  Fast.  Good feel.  Good balance.  Great for Japanese Penhold.
>
>Not quite as good for Chinese penhold.  The single grain direction
>makes the sweet spot sort-of skinny.  Multi-ply has a broader sweet
>spot.  Sweet spot refers to the area of the paddle that is most
>uniform.  A larger sweet spot allows you to play strong shots which
>don't hit the center of the paddle.
>
>I have also made Chinese penhold paddles out of 7 plies of sitka
>spruce veneer.  It is tough to buy.  They will only sell it in
>large quantities.  However, the paddles are very good.  I have yet
>to try cedar veneer.  I can't find it.
>
>Friends have made paddles very differently.  They buy thin hobby
>plywood and THICK hobby balsawood.  They glue the plywood as top
>and bottom veneer over the balsawood core.  The paddles that they
>make come out light because of the balsa and fast because of the strong
>plywood "skins".  The furniture industry refers to this style of
>construction as a torsion box, a weak core and strong skins.
>It has only one weakness: it wears out faster than a normal paddle.
>However, it is cheap, easy to make, and allows you to "tune" performance
>by adjusting the balsa thickness.
>
>Happy Paddle Making!
>
>--
>Bob Neidorff; Unitrode I. C. Corp.  |  Internet: neidorff@uicc.com
>7 Continental Blvd.                 |  Voice   : (US) 603-424-2410
>Merrimack, NH  03054-0399 USA       |  FAX     : (US) 603-424-3460
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