Is there a formula or chart or anything available for elliptical 
curves? I've had good success with radial curves using the charts in 
the files section, but i've come up with nothing on elliptical curves. 
I've tried calculating them myself and apparently my math skills 
aren't what they once were...at one time in my life i passed an AP 
calc class without much trouble, but that was an undergraduate degree 
in jazz studies ago. any insight would be appreciated. thanks- mike 

Can anyone recommend a mouth-safe epoxy or glue for reattaching a bite 
guard? I was considering using some dental epoxy since that's safe, but 
because it's so specific to "teeth" the box doesn't mention if it works for 
rubber or plastic. This is the simple little temporary tooth repair kits 
you can buy at the drug store. I suppose I could just try it and see if it 
works, but figured I'd ask first.

This is one of the newer Berg Larsen mpc's. I got it cheap and it actually 
plays pretty well but good grief does the quality suck. I dropped it onto 
carpet from a height of 3 feet and the bite guard just fell out without any 
(other) damage. Not much sign of previous epoxy or glue so it's no wonder 
it fell out. My 16 yr old Berg shows a white-colored epoxy peaking out from 
around the edges (I bought it from the factory 16 yrs ago, so apparently 
they're using something different now).

Thanks,
Kirk

--- In MouthpieceWork@yahoogroups.com, "saxjazz42" <dulcimercat@...> 
wrote:
>
> Is there a formula or chart or anything available for elliptical 
> curves? I've had good success with radial curves using the charts in 
> the files section, but i've come up with nothing on elliptical 
curves. 
> I've tried calculating them myself and apparently my math skills 
> aren't what they once were...at one time in my life i passed an AP 
> calc class without much trouble, but that was an undergraduate degree 
> in jazz studies ago. any insight would be appreciated. thanks- mike

I did a lot of research on elliptical curves a few years back and there 
is no exact formula for this type of curve,  there are some that come 
close but none exact.  Tom
>

You will need to make up your own mind what is safe.  This has been
discussed several times here.  The Search feature is note that great, but
after hitting it a few time to bring up older posts you should find some
info.

One thing I find interesting is that the general mouthpiece-playing public
just assumes that the original bite plate and epoxy materials are
non-toxic.  I'm unaware of any regulatory agency that insures this for us. 
The closest thing we have in the US are MSDS sheets.  I doubt anyone has
asked a mouthpiece maker to supply these for the materials they use.  I'm
not real concerned, but I find the trust in the makers and distrust in the
repairers (me) a little out of wack.

MSDS sheets are fairly easy to get for epoxy repair materials.  I have them
for several of the materials I use.  But there are on-going studies and
debates that there are dangers not disclosed in these data sheets. 
Generally speaking, epoxy components can be dangerous but become safe
(safer) when thoroughly mixed and cured.  This can be said of Dental
epoxies too.

I would use a clear 5-minute epoxy to reattach the bite plate.  Devcon is
one brand.  http://www.devcon.com/devconfamilyproduct.cfm?familyid5

The MSDS says in the beginning: "After curing, this product is
non-hazardous."  Then is descibes some of the nastys the separate hardener
and resin can do.


       
____________________________________________________________________________________
Yahoo! oneSearch: Finally, mobile search 
that gives answers, not web links. 
http://mobile.yahoo.com/mobileweb/onesearch?refer=1ONXIC

Yeah, for the record I don't really trust that the original epoxy was safe 
either, but I'm not worrying about it too much (we could waste our lives 
just worrying about everything). I thought about looking into plumber's 
epoxy also since drinking water could come into contact with it and 
presumably be safe.

Thanks for the info! And I'll try to use the Search feature more, too.

-Kirk

At 03:46 PM 7/17/2007 -0700, you wrote:
>You will need to make up your own mind what is safe.  This has been
>discussed several times here.  The Search feature is note that great, but
>after hitting it a few time to bring up older posts you should find some
>info.
>
>One thing I find interesting is that the general mouthpiece-playing public
>just assumes that the original bite plate and epoxy materials are
>non-toxic.  I'm unaware of any regulatory agency that insures this for us.
>The closest thing we have in the US are MSDS sheets.  I doubt anyone has
>asked a mouthpiece maker to supply these for the materials they use.  I'm
>not real concerned, but I find the trust in the makers and distrust in the
>repairers (me) a little out of wack.
>
>MSDS sheets are fairly easy to get for epoxy repair materials.  I have them
>for several of the materials I use.  But there are on-going studies and
>debates that there are dangers not disclosed in these data sheets.
>Generally speaking, epoxy components can be dangerous but become safe
>(safer) when thoroughly mixed and cured.  This can be said of Dental
>epoxies too.
>
>I would use a clear 5-minute epoxy to reattach the bite plate.  Devcon is
>one brand.  http://www.devcon.com/devconfamilyproduct.cfm?familyid5
>
>The MSDS says in the beginning: "After curing, this product is
>non-hazardous."  Then is descibes some of the nastys the separate hardener
>and resin can do.
>
>
>
>____________________________________________________________________________________
>Yahoo! oneSearch: Finally, mobile search
>that gives answers, not web links.
>http://mobile.yahoo.com/mobileweb/onesearch?refer=1ONXIC
>
>
>Got a Mouthpiece Work question?  Send it to MouthpieceWork@yahoogroups.com
>
>Visit the site at http://groups.yahoo.com/group/MouthpieceWork to see the 
>Files, Photos and Bookmarks relating to Mouthpiece Work.
>
>To see and modify your groups, go to http://groups.yahoo.com/mygroups
>Yahoo! Groups Links
>
>
>

> I did a lot of research on elliptical curves a few years back and 
there 
> is no exact formula for this type of curve,  there are some that 
come 
> close but none exact.  Tom

I have developed my own elliptical facing curve formula.  One day I 
plan to share it with the world, but for now it is one of the few 
things I have that I consider proprietary.  But I'll talk about it to 
some extent.

Also take a look at Theo's new site for how he calculates facing 
curves using a quadratic curve fit of his extensive database.  I think 
the curves he came up are not distinguishable from elliptical curves.  
However he does not give you the equation constants that make it all 
work.

indeed, i noticed that about theo's site. it gave me the idea that 
there is a way to formulate this information. i probably coulda 
figured this out about 5 years ago in calc class...i understand the 
need to keep some info personal though. thanks for all the other 
great info on this site, it has helped greatly. -mike 


--- In MouthpieceWork@yahoogroups.com, "Keith Bradbury" 
<kwbradbury@...> wrote:
>
> > I did a lot of research on elliptical curves a few years back 
and 
> there 
> > is no exact formula for this type of curve,  there are some that 
> come 
> > close but none exact.  Tom
> 
> I have developed my own elliptical facing curve formula.  One day 
I 
> plan to share it with the world, but for now it is one of the few 
> things I have that I consider proprietary.  But I'll talk about it 
to 
> some extent.
> 
> Also take a look at Theo's new site for how he calculates facing 
> curves using a quadratic curve fit of his extensive database.  I 
think 
> the curves he came up are not distinguishable from elliptical 
curves.  
> However he does not give you the equation constants that make it 
all 
> work.
>

Epoxies contain Bisphenol Alpha, and there are questions about its safety. At present most regulatory agencies consider it safe:
   
  http://www.bisphenol-a.org/sixty-minutes2a.html
   
  Here's the Wikipedia entry:
   
  http://www.bisphenol-a.org/sixty-minutes2a.html
   
  Toby
   
  

Kirk Lund <klund@...> wrote:
          Yeah, for the record I don't really trust that the original epoxy was safe 
either, but I'm not worrying about it too much (we could waste our lives 
just worrying about everything). I thought about looking into plumber's 
epoxy also since drinking water could come into contact with it and 
presumably be safe.

Thanks for the info! And I'll try to use the Search feature more, too.

-Kirk

At 03:46 PM 7/17/2007 -0700, you wrote:
>You will need to make up your own mind what is safe. This has been
>discussed several times here. The Search feature is note that great, but
>after hitting it a few time to bring up older posts you should find some
>info.
>
>One thing I find interesting is that the general mouthpiece-playing public
>just assumes that the original bite plate and epoxy materials are
>non-toxic. I'm unaware of any regulatory agency that insures this for us.
>The closest thing we have in the US are MSDS sheets. I doubt anyone has
>asked a mouthpiece maker to supply these for the materials they use. I'm
>not real concerned, but I find the trust in the makers and distrust in the
>repairers (me) a little out of wack.
>
>MSDS sheets are fairly easy to get for epoxy repair materials. I have them
>for several of the materials I use. But there are on-going studies and
>debates that there are dangers not disclosed in these data sheets.
>Generally speaking, epoxy components can be dangerous but become safe
>(safer) when thoroughly mixed and cured. This can be said of Dental
>epoxies too.
>
>I would use a clear 5-minute epoxy to reattach the bite plate. Devcon is
>one brand. http://www.devcon.com/devconfamilyproduct.cfm?familyid5
>
>The MSDS says in the beginning: "After curing, this product is
>non-hazardous." Then is descibes some of the nastys the separate hardener
>and resin can do.
>
>
>
>__________________________________________________________
>Yahoo! oneSearch: Finally, mobile search
>that gives answers, not web links.
>http://mobile.yahoo.com/mobileweb/onesearch?refer=1ONXIC
>
>
>Got a Mouthpiece Work question? Send it to MouthpieceWork@yahoogroups.com
>
>Visit the site at http://groups.yahoo.com/group/MouthpieceWork to see the 
>Files, Photos and Bookmarks relating to Mouthpiece Work.
>
>To see and modify your groups, go to http://groups.yahoo.com/mygroups
>Yahoo! Groups Links
>
>
>



         
 

I use the following equations. In these

x = distance along facing
x = 0 at the point where the plane of the table is tangent to the
curve of the facing (x = 0 is NOT the tip!)

y = opening of the facing

Circular facing with raduis "r"
x^2 + y^2 - 2yr = 0
			
Parabolic facing with constant "a"
y - a x^2 = 0
			
Ellipse must specify aspect ratio "ar" and constant "a"
ar^2 x^2 + y^2 - ar a y = 0
for 2:1 ellipse 
4 x^2 + y^2 - 2 a y = 0

Of course, the values of x and y must be converted to the appropriate
scales. I use these equations to find the best fit of measured data to
a geometric facing, but I first convert the scale reading and the
thickness of the gages into the same units for fitting. I will try to
upload a spreadsheet demonstrating this into the "files" section.

- Brent 

--- In MouthpieceWork@yahoogroups.com, "saxjazz42" <dulcimercat@...>
wrote:
>
> Is there a formula or chart or anything available for elliptical 
> curves? I've had good success with radial curves using the charts in 
> the files section, but i've come up with nothing on elliptical curves. 
> I've tried calculating them myself and apparently my math skills 
> aren't what they once were...at one time in my life i passed an AP 
> calc class without much trouble, but that was an undergraduate degree 
> in jazz studies ago. any insight would be appreciated. thanks- mike
>

I am a dentist and can tell you these temporary epoxies are not 
strong enough to hold a bite guard. most are zinc oxide and eugenal 
(clove oil).Also all dental repair resins are relatively non - toxic 
once cured. They are closely regulated.
 Chic


-- In MouthpieceWork@yahoogroups.com, Kirk Lund <klund@...> wrote:
>
> Can anyone recommend a mouth-safe epoxy or glue for reattaching a 
bite 
> guard? I was considering using some dental epoxy since that's safe, 
but 
> because it's so specific to "teeth" the box doesn't mention if it 
works for 
> rubber or plastic. This is the simple little temporary tooth repair 
kits 
> you can buy at the drug store. I suppose I could just try it and 
see if it 
> works, but figured I'd ask first.
> 
> This is one of the newer Berg Larsen mpc's. I got it cheap and it 
actually 
> plays pretty well but good grief does the quality suck. I dropped 
it onto 
> carpet from a height of 3 feet and the bite guard just fell out 
without any 
> (other) damage. Not much sign of previous epoxy or glue so it's no 
wonder 
> it fell out. My 16 yr old Berg shows a white-colored epoxy peaking 
out from 
> around the edges (I bought it from the factory 16 yrs ago, so 
apparently 
> they're using something different now).
> 
> Thanks,
> Kirk
>

Brent:

Please notify when the spreadsheet is posted. 

What does the small arrow between x and 2 indicate? Squared?

Thanks
--- In MouthpieceWork@yahoogroups.com, "Brent" <brentsmith@...> wrote:
>
> I use the following equations. In these
> 
> x = distance along facing
> x = 0 at the point where the plane of the table is tangent to the
> curve of the facing (x = 0 is NOT the tip!)
> 
> y = opening of the facing
> 
> Circular facing with raduis "r"
> x^2 + y^2 - 2yr = 0
> 			
> Parabolic facing with constant "a"
> y - a x^2 = 0
> 			
> Ellipse must specify aspect ratio "ar" and constant "a"
> ar^2 x^2 + y^2 - ar a y = 0
> for 2:1 ellipse 
> 4 x^2 + y^2 - 2 a y = 0
> 
> Of course, the values of x and y must be converted to the 
appropriate
> scales. I use these equations to find the best fit of measured data 
to
> a geometric facing, but I first convert the scale reading and the
> thickness of the gages into the same units for fitting. I will try 
to
> upload a spreadsheet demonstrating this into the "files" section.
> 
> - Brent 
> 

thank you very much...i'll see what i can do with this. -mike 


--- In MouthpieceWork@yahoogroups.com, "Greg Wier" <gregwier@...> 
wrote:
>
> Brent:
> 
> Please notify when the spreadsheet is posted. 
> 
> What does the small arrow between x and 2 indicate? Squared?
> 
> Thanks
> --- In MouthpieceWork@yahoogroups.com, "Brent" <brentsmith@> wrote:
> >
> > I use the following equations. In these
> > 
> > x = distance along facing
> > x = 0 at the point where the plane of the table is tangent to the
> > curve of the facing (x = 0 is NOT the tip!)
> > 
> > y = opening of the facing
> > 
> > Circular facing with raduis "r"
> > x^2 + y^2 - 2yr = 0
> > 			
> > Parabolic facing with constant "a"
> > y - a x^2 = 0
> > 			
> > Ellipse must specify aspect ratio "ar" and constant "a"
> > ar^2 x^2 + y^2 - ar a y = 0
> > for 2:1 ellipse 
> > 4 x^2 + y^2 - 2 a y = 0
> > 
> > Of course, the values of x and y must be converted to the 
> appropriate
> > scales. I use these equations to find the best fit of measured 
data 
> to
> > a geometric facing, but I first convert the scale reading and the
> > thickness of the gages into the same units for fitting. I will 
try 
> to
> > upload a spreadsheet demonstrating this into the "files" section.
> > 
> > - Brent 
> >
>

Hey Chic

What about glass ionomer cement for this use?
Any other safe dental adhesives that you might suggest?

I think the search here is for a clearly certified safe adhesive (not 
just a vague MSDS sheet recommendation).

Thanks,

Ted



At 08:49 AM 7/18/2007, you wrote:

>I am a dentist and can tell you these temporary epoxies are not
>strong enough to hold a bite guard. most are zinc oxide and eugenal
>(clove oil).Also all dental repair resins are relatively non - toxic
>once cured. They are closely regulated.
>Chic
>
>-- In 
><mailto:MouthpieceWork%40yahoogroups.com>MouthpieceWork@yahoogroups.com, 
>Kirk Lund <klund@...> wrote:
> >
> > Can anyone recommend a mouth-safe epoxy or glue for reattaching a
>bite
> > guard? I was considering using some dental epoxy since that's safe,
>but
> > because it's so specific to "teeth" the box doesn't mention if it
>works for
> > rubber or plastic. This is the simple little temporary tooth repair
>kits
> > you can buy at the drug store. I suppose I could just try it and
>see if it
> > works, but figured I'd ask first.
> >
> > This is one of the newer Berg Larsen mpc's. I got it cheap and it
>actually
> > plays pretty well but good grief does the quality suck. I dropped
>it onto
> > carpet from a height of 3 feet and the bite guard just fell out
>without any
> > (other) damage. Not much sign of previous epoxy or glue so it's no
>wonder
> > it fell out. My 16 yr old Berg shows a white-colored epoxy peaking
>out from
> > around the edges (I bought it from the factory 16 yrs ago, so
>apparently
> > they're using something different now).
> >
> > Thanks,
> > Kirk
> >
>
>

Hi Ted.
Glass ionomers as are many of the dental "cements" are actually not 
cements.  They are luting agents.  The difference is that a luting 
agent fills in the microscopic voids between the casting and the 
tooth.  It doesn't have "sticky" properties like say contact cement.  
One good sticky dental cement that comes to mind is Durelon.  It has 
a high sticky property, is impervious to saliva and gets quite hard.  
Its kindof pink when dried but its non toxic.
Chic






--- In MouthpieceWork@yahoogroups.com, Ted Botaska 
<tuesdayhockey@...> wrote:
>
> 
> Hey Chic
> 
> What about glass ionomer cement for this use?
> Any other safe dental adhesives that you might suggest?
> 
> I think the search here is for a clearly certified safe adhesive 
(not 
> just a vague MSDS sheet recommendation).
> 
> Thanks,
> 
> Ted
> 
> 
> 
> At 08:49 AM 7/18/2007, you wrote:
> 
> >I am a dentist and can tell you these temporary epoxies are not
> >strong enough to hold a bite guard. most are zinc oxide and eugenal
> >(clove oil).Also all dental repair resins are relatively non - 
toxic
> >once cured. They are closely regulated.
> >Chic
> >
> >-- In 
> ><mailto:MouthpieceWork%
40yahoogroups.com>MouthpieceWork@yahoogroups.com, 
> >Kirk Lund <klund@> wrote:
> > >
> > > Can anyone recommend a mouth-safe epoxy or glue for reattaching 
a
> >bite
> > > guard? I was considering using some dental epoxy since that's 
safe,
> >but
> > > because it's so specific to "teeth" the box doesn't mention if 
it
> >works for
> > > rubber or plastic. This is the simple little temporary tooth 
repair
> >kits
> > > you can buy at the drug store. I suppose I could just try it and
> >see if it
> > > works, but figured I'd ask first.
> > >
> > > This is one of the newer Berg Larsen mpc's. I got it cheap and 
it
> >actually
> > > plays pretty well but good grief does the quality suck. I 
dropped
> >it onto
> > > carpet from a height of 3 feet and the bite guard just fell out
> >without any
> > > (other) damage. Not much sign of previous epoxy or glue so it's 
no
> >wonder
> > > it fell out. My 16 yr old Berg shows a white-colored epoxy 
peaking
> >out from
> > > around the edges (I bought it from the factory 16 yrs ago, so
> >apparently
> > > they're using something different now).
> > >
> > > Thanks,
> > > Kirk
> > >
> >
> >
>

> Please notify when the spreadsheet is posted. 
> 

It is posted in the Files - Clarinet section.

I need to study it a little more.  The examples Brent used show no
significant difference between the radial, elliptical, and parabolic curve
for clarinet.  The elliptical aspect ratio he used is = 2.  A more
exaggerated 4 is more common for sax facing curves, but they vary a lot.

His parabolic curve is reversed from what I have heard some clarinet makers
use.  Theirs start more curved at the table and become straighter towards
the tip.  This can also be approximated with an elliptical curve that has
an aspect ration less than one.



       
____________________________________________________________________________________
Be a better Heartthrob. Get better relationship answers from someone who knows. Yahoo! Answers - Check it out. 
http://answers.yahoo.com/dir/?link=list&sid96545433

Inspired by these posts, I've created my own spreadsheet for
calculating elliptical shaped facing curves.  You can also compare the
results to a radial curve.  The elliptical ratio can changed by simply
changing the value in the  yellow input box and the curve will update.
 You can see that for ratios of 2 or less, the ellipse becomes
virtually identical to a radial curve.

The formula for the radial curve is based on pythagoras's triangle to
find the coordinates for the circle.  The elliptical formula is the
same, but stretched sideways according to the ellipical ratio.

Hope this is useful . . .


Regards, Andrew


--- In MouthpieceWork@yahoogroups.com, Keith Bradbury <kwbradbury@...>
wrote:
>
> > Please notify when the spreadsheet is posted. 
> > 
> 
> It is posted in the Files - Clarinet section.
> 
> I need to study it a little more.  The examples Brent used show no
> significant difference between the radial, elliptical, and parabolic
curve
> for clarinet.  The elliptical aspect ratio he used is = 2.  A more
> exaggerated 4 is more common for sax facing curves, but they vary a lot.
> 
> His parabolic curve is reversed from what I have heard some clarinet
makers
> use.  Theirs start more curved at the table and become straighter
towards
> the tip.  This can also be approximated with an elliptical curve
that has
> an aspect ration less than one.
> 
> 
> 
>        
>
____________________________________________________________________________________
> Be a better Heartthrob. Get better relationship answers from someone
who knows. Yahoo! Answers - Check it out. 
> http://answers.yahoo.com/dir/?link=list&sid96545433
>

Andrew put this file in the Files - Methods section last July.  I 
missed taking a look at it until now.  It looks like a nice 
implementation.  It has a lot of features similar to what I use. 

--- In MouthpieceWork@yahoogroups.com, "andrewhdonaldson" 
<andrewhdonaldson@...> wrote:
>
> Inspired by these posts, I've created my own spreadsheet for
> calculating elliptical shaped facing curves.  You can also compare 
the
> results to a radial curve.  The elliptical ratio can changed by 
simply
> changing the value in the  yellow input box and the curve will 
update.
>  You can see that for ratios of 2 or less, the ellipse becomes
> virtually identical to a radial curve.
> 
> The formula for the radial curve is based on pythagoras's triangle 
to
> find the coordinates for the circle.  The elliptical formula is the
> same, but stretched sideways according to the ellipical ratio.
> 
> Hope this is useful . . .
> 
> 
> Regards, Andrew
> 
> 

Thanks!


--- In MouthpieceWork@yahoogroups.com, "Keith Bradbury"
<kwbradbury@...> wrote:
>
> Andrew put this file in the Files - Methods section last July.  I 
> missed taking a look at it until now.  It looks like a nice 
> implementation.  It has a lot of features similar to what I use. 
> 
> --- In MouthpieceWork@yahoogroups.com, "andrewhdonaldson" 
> <andrewhdonaldson@> wrote:
> >
> > Inspired by these posts, I've created my own spreadsheet for
> > calculating elliptical shaped facing curves.  You can also compare 
> the
> > results to a radial curve.  The elliptical ratio can changed by 
> simply
> > changing the value in the  yellow input box and the curve will 
> update.
> >  You can see that for ratios of 2 or less, the ellipse becomes
> > virtually identical to a radial curve.
> > 
> > The formula for the radial curve is based on pythagoras's triangle 
> to
> > find the coordinates for the circle.  The elliptical formula is the
> > same, but stretched sideways according to the ellipical ratio.
> > 
> > Hope this is useful . . .
> > 
> > 
> > Regards, Andrew
> > 
> >
>