Home machining

[Anthony W]

Can anyone recommend a good forum for home machine work? Not the news
group, that's a madhouse...

Tony

[Dan[_12_]]

Anthony W wrote:
> Can anyone recommend a good forum for home machine work? Not the news
> group, that's a madhouse...
>
> Tony

If you want a place with good customer support try:
http://littlemachineshop.com/

The people there always answer my questions about how to do things
and the make suggestions for trouble I get myself into.

Dan, U.S. Air Force, retired

[R[_2_]]

Anthony W wrote:
> Can anyone recommend a good forum for home machine work? Not the news
> group, that's a madhouse...
>
> Tony

The Home Machinist
http://www.chaski.org/homemachinist/

The Home Shop Machinist & Machinist's Workshop BBS
http://bbs.homeshopmachinist.net/


If you have some metalworking or machining experience this group has the
most expertise. They do not tolerate well inane questions from wannabes.
A wealth of knowledge can be gained by, even, lurking here.

Practical Machinist
http://www.practicalmachinist.com/vb/

[Anthony W]

Thanx guys I have book marked those pages.

Tony

[Stu Fields]

"R" > wrote in message
...
> Anthony W wrote:
>> Can anyone recommend a good forum for home machine work? Not the news
>> group, that's a madhouse...
>>
>> Tony
>
> The Home Machinist
> http://www.chaski.org/homemachinist/
>
> The Home Shop Machinist & Machinist's Workshop BBS
> http://bbs.homeshopmachinist.net/
>
>
> If you have some metalworking or machining experience this group has the
> most expertise. They do not tolerate well inane questions from wannabes. A
> wealth of knowledge can be gained by, even, lurking here.
>
> Practical Machinist
> http://www.practicalmachinist.com/vb/

Thank you a bunch. The Practical Machinist is just what I've been looking
for...

Stu Fields Safari helicopter and now a Helicycle

[Peter Dohm]

"R" > wrote in message
...
> Anthony W wrote:
>> Can anyone recommend a good forum for home machine work? Not the news
>> group, that's a madhouse...
>>
>> Tony
>
> The Home Machinist
> http://www.chaski.org/homemachinist/
>
> The Home Shop Machinist & Machinist's Workshop BBS
> http://bbs.homeshopmachinist.net/
>
>
> If you have some metalworking or machining experience this group has the
> most expertise. They do not tolerate well inane questions from wannabes. A
> wealth of knowledge can be gained by, even, lurking here.
>
> Practical Machinist
> http://www.practicalmachinist.com/vb/

Looking at this thread makes me just a little curious whether the
relationship of cost and capability may have brought the CNC routing/milling
process to make precision foam cores--such as used in the Vari-Eze and its
derivatives--within reasonable reach of the home builder. The hot wire
method worked reasonably well in its day; but was limited to certain types
of foam and also resulted in a slight sag in the shape of the resulting
parts.

Of course, I have kept a list of the above forum locations; and I am curious
if anyone happens to know the present cost of setting up that sort of CNC
system for the cores in something like a Vari-Eze.

Peter

[Dan[_12_]]

Peter Dohm wrote:
> "R" > wrote in message
> ...
>> Anthony W wrote:
>>> Can anyone recommend a good forum for home machine work? Not the news
>>> group, that's a madhouse...
>>>
>>> Tony
>> The Home Machinist
>> http://www.chaski.org/homemachinist/
>>
>> The Home Shop Machinist & Machinist's Workshop BBS
>> http://bbs.homeshopmachinist.net/
>>
>>
>> If you have some metalworking or machining experience this group has the
>> most expertise. They do not tolerate well inane questions from wannabes. A
>> wealth of knowledge can be gained by, even, lurking here.
>>
>> Practical Machinist
>> http://www.practicalmachinist.com/vb/
>
> Looking at this thread makes me just a little curious whether the
> relationship of cost and capability may have brought the CNC routing/milling
> process to make precision foam cores--such as used in the Vari-Eze and its
> derivatives--within reasonable reach of the home builder. The hot wire
> method worked reasonably well in its day; but was limited to certain types
> of foam and also resulted in a slight sag in the shape of the resulting
> parts.
>
> Of course, I have kept a list of the above forum locations; and I am curious
> if anyone happens to know the present cost of setting up that sort of CNC
> system for the cores in something like a Vari-Eze.
>
> Peter
>

I would imagine it's a matter of scale. In theory it would be
possible, I have seen kits for 2 dimensional systems for using
oxy-acetylene torches to cut sheet metal and a home PC. I wonder if such
a sytem could be modified to 3 dimensions. Rigidity of the machinery
would require a rather massive frame. One additional consideration would
be dust collection.

I wonder if the system could also be used to finish the part after
layup.

A creative mind would be able make some amazing shapes.

Dan, U.S. Air Force, retired

[Atheist Chaplain[_2_]]

"Dan" > wrote in message
...
> Peter Dohm wrote:
>> "R" > wrote in message
>> ...
>>> Anthony W wrote:
>>>> Can anyone recommend a good forum for home machine work? Not the news
>>>> group, that's a madhouse...
>>>>
>>>> Tony
>>> The Home Machinist
>>> http://www.chaski.org/homemachinist/
>>>
>>> The Home Shop Machinist & Machinist's Workshop BBS
>>> http://bbs.homeshopmachinist.net/
>>>
>>>
>>> If you have some metalworking or machining experience this group has the
>>> most expertise. They do not tolerate well inane questions from wannabes.
>>> A wealth of knowledge can be gained by, even, lurking here.
>>>
>>> Practical Machinist
>>> http://www.practicalmachinist.com/vb/
>>
>> Looking at this thread makes me just a little curious whether the
>> relationship of cost and capability may have brought the CNC
>> routing/milling process to make precision foam cores--such as used in the
>> Vari-Eze and its derivatives--within reasonable reach of the home
>> builder. The hot wire method worked reasonably well in its day; but was
>> limited to certain types of foam and also resulted in a slight sag in the
>> shape of the resulting parts.
>>
>> Of course, I have kept a list of the above forum locations; and I am
>> curious if anyone happens to know the present cost of setting up that
>> sort of CNC system for the cores in something like a Vari-Eze.
>>
>> Peter
>>
>
> I would imagine it's a matter of scale. In theory it would be possible,
> I have seen kits for 2 dimensional systems for using oxy-acetylene torches
> to cut sheet metal and a home PC. I wonder if such a sytem could be
> modified to 3 dimensions. Rigidity of the machinery would require a rather
> massive frame. One additional consideration would be dust collection.
>
> I wonder if the system could also be used to finish the part after
> layup.
>
> A creative mind would be able make some amazing shapes.
>
> Dan, U.S. Air Force, retired

Here is a starting point :-)

http://www.instructables.com/id/How-to-Make-a-Three-Axis-CNC-Machine-Cheaply-and-/

--
[This comment is no longer available due to a copyright claim by Church of
Scientology International]
"I like your Christ. I do not like your Christians. They are so unlike your
Christ." Gandhi

[flash]

"Anthony W" > wrote in message
...
> Can anyone recommend a good forum for home machine work? Not the news
> group, that's a madhouse...
>
> Tony

Lately the signal to noise ratio has gone sour, but

rec,crafts.metalworking

has been pretty fair, too. Lots of knowledgeable people still there, but an
increasing number of cross-posters dump on it, too. Just have to look and
ignore some threads, posters.

Flash

[Anthony W]

Flash wrote:
> Lately the signal to noise ratio has gone sour, but
>
> rec,crafts.metalworking
>
> has been pretty fair, too. Lots of knowledgeable people still there, but an
> increasing number of cross-posters dump on it, too. Just have to look and
> ignore some threads, posters.
>
> Flash

I tried that group for a few day and I found it not worth the insanity...

Tony

[cavelamb[_2_]]

Anthony W wrote:
> Flash wrote:
>> Lately the signal to noise ratio has gone sour, but
>>
>> rec,crafts.metalworking
>>
>> has been pretty fair, too. Lots of knowledgeable people still there,
>> but an increasing number of cross-posters dump on it, too. Just have
>> to look and ignore some threads, posters.
>>
>> Flash
>
> I tried that group for a few day and I found it not worth the insanity...
>
> Tony

There are about 6 guys that have to be filtered out.
Then it gets back to usable...

[R[_2_]]

Peter Dohm wrote:
> Of course, I have kept a list of the above forum locations; and I am curious
> if anyone happens to know the present cost of setting up that sort of CNC
> system for the cores in something like a Vari-Eze.
>
> Peter
Along with Practical Machinist's, and Chaski's Home Machinist, CNC
sections, add for homebrew CNC:
CNCzone.com
http://www.cnczone.com/
A group to monitor, if you are interested in developing a homebrew CNC
machine to mill or cut out your next skychaser.
The cost depends on your own vision of the machine, the task, and your
expected production.

[Stealth Pilot[_2_]]

On Sat, 15 Aug 2009 02:28:40 GMT, Anthony W >
wrote:

>Can anyone recommend a good forum for home machine work? Not the news
>group, that's a madhouse...
>
>Tony

Tony you could always post your questions here.
there are a few knowledgeable builders here believe it or not.

Stealth Pilot

[R[_2_]]

R wrote:
add for homebrew CNC:
> CNCzone.com
> http://www.cnczone.com/
OOPs!
link direct to the forums page:
http://www.cnczone.com/forums/index.php

Homebrew CNC machine's costs are determined by how good you can scrounge.

[Tim[_8_]]

"Peter Dohm" > wrote in message
...
> "R" > wrote in message
> ...
>> Anthony W wrote:
>>> Can anyone recommend a good forum for home machine work? Not the news
>>> group, that's a madhouse...
>>>
>>> Tony
>>
>> The Home Machinist
>> http://www.chaski.org/homemachinist/
>>
>> The Home Shop Machinist & Machinist's Workshop BBS
>> http://bbs.homeshopmachinist.net/
>>
>>
>> If you have some metalworking or machining experience this group has the
>> most expertise. They do not tolerate well inane questions from wannabes.
>> A wealth of knowledge can be gained by, even, lurking here.
>>
>> Practical Machinist
>> http://www.practicalmachinist.com/vb/
>
> Looking at this thread makes me just a little curious whether the
> relationship of cost and capability may have brought the CNC
> routing/milling process to make precision foam cores--such as used in the
> Vari-Eze and its derivatives--within reasonable reach of the home builder.
> The hot wire method worked reasonably well in its day; but was limited to
> certain types of foam and also resulted in a slight sag in the shape of
> the resulting parts.
>
> Of course, I have kept a list of the above forum locations; and I am
> curious if anyone happens to know the present cost of setting up that sort
> of CNC system for the cores in something like a Vari-Eze.
>
> Peter

It seems to me it's still about software for inputting the image and
generating the G code. There have been home brew stepper systems around for
years that would meet the requirements, but software still seems to be the
tough part. Seems it's all either too expensive or lacks function.

[Brian Whatcott]

Anthony W wrote:
> Flash wrote:
>> Lately the signal to noise ratio has gone sour, but
>>
>> rec,crafts.metalworking
>>
>> has been pretty fair, too. Lots of knowledgeable people still there,
>> but an increasing number of cross-posters dump on it, too. Just have
>> to look and ignore some threads, posters.
>>
>> Flash
>
> I tried that group for a few day and I found it not worth the insanity...
>
> Tony

It was quite a few years ago that I mentioned the use of 6061 alloy in
aircraft, and was consistently abused and sneered at by some kind of
free lance tech writer, for not knowing that 2024 was the ONLY aerospace
aluminum alloy then in use. So I gave up on it....

Brian W

[Anthony W]

Stealth Pilot wrote:
> Tony you could always post your questions here.
> there are a few knowledgeable builders here believe it or not.
>
> Stealth Pilot

Actually I do believe it. This is the primary reason I hang out here.

Right now I'm looking to undertake a project that will require that I
buy a lathe and I my next step is to choose one that is worth the 500 or
600 bucks I can scrape up to pay for it...

Tony

[bildan]

On Aug 15, 7:10*pm, "Peter Dohm" > wrote:
> "R" > wrote in message
>
> ...
>
>
>
> > Anthony W wrote:
> >> Can anyone recommend a good forum for home machine work? *Not the news
> >> group, that's a madhouse...
>
> >> Tony
>
> > The Home Machinist
> >http://www.chaski.org/homemachinist/
>
> > The Home Shop Machinist & Machinist's Workshop BBS
> >http://bbs.homeshopmachinist.net/
>
> > If you have some metalworking or machining experience this group has the
> > most expertise. They do not tolerate well inane questions from wannabes.. A
> > wealth of knowledge can be gained by, even, lurking here.
>
> > *Practical Machinist
> >http://www.practicalmachinist.com/vb/
>
> Looking at this thread makes me just a little curious whether the
> relationship of cost and capability may have brought the CNC routing/milling
> process to make precision foam cores--such as used in the Vari-Eze and its
> derivatives--within reasonable reach of the home builder. *The hot wire
> method worked reasonably well in its day; but was limited to certain types
> of foam and also resulted in a slight sag in the shape of the resulting
> parts.
>
> Of course, I have kept a list of the above forum locations; and I am curious
> if anyone happens to know the present cost of setting up that sort of CNC
> system for the cores in something like a Vari-Eze.
>
> Peter

Back in the '80's I was allowed to watch a huge CNC machine at Martin
Marietta in Waterton, CO carve a Learjet wing out of an enormous
aluminum billet. When finished, it was complete right down to 6-32
tapped holes.

I've kicked around a "wing machine" idea for years. My idea was to
cut female molds and then build the aircraft using standard wet layup
composite techniques.

[Stealth Pilot[_2_]]

On Sun, 16 Aug 2009 17:14:52 GMT, Anthony W >
wrote:

>Stealth Pilot wrote:
>> Tony you could always post your questions here.
>> there are a few knowledgeable builders here believe it or not.
>>
>> Stealth Pilot
>
>Actually I do believe it. This is the primary reason I hang out here.
>
>Right now I'm looking to undertake a project that will require that I
>buy a lathe and I my next step is to choose one that is worth the 500 or
>600 bucks I can scrape up to pay for it...
>
>Tony

I'm a lousy dentist.
what's the project?

Stealth Pilot

[Stealth Pilot[_2_]]

On Sun, 16 Aug 2009 11:52:48 -0500, brian whatcott
> wrote:

>Anthony W wrote:
>> Flash wrote:
>>> Lately the signal to noise ratio has gone sour, but
>>>
>>> rec,crafts.metalworking
>>>
>>> has been pretty fair, too. Lots of knowledgeable people still there,
>>> but an increasing number of cross-posters dump on it, too. Just have
>>> to look and ignore some threads, posters.
>>>
>>> Flash
>>
>> I tried that group for a few day and I found it not worth the insanity...
>>
>> Tony
>
>It was quite a few years ago that I mentioned the use of 6061 alloy in
>aircraft, and was consistently abused and sneered at by some kind of
>free lance tech writer, for not knowing that 2024 was the ONLY aerospace
>aluminum alloy then in use. So I gave up on it....
>
>Brian W


thats why we like aeroplanes and not aerospace.
.....like aerospace is waaaaay out there man.

but in aeroplanes we get to play with 3003, 5005, 2011, 6061 and lotsa
kool stuff that cant be used in aerospace.
hell yesterday I even machined some god awful steel component and made
it look pretty. I replaced a worn spinner support in 1214.
we have lots more fun in aeroplanes.

....they dont even have propellers in aerospace. how backward is that!

I've even got brass nuts I made myself on my aeroplane.

but you hafta admit that aerospace has way cooler x-prizes.
there is one for a home made space vehicle plonked on the moon with a
home made rocket. you hafta remotely drive up to some expensive nasa
thingy on the moon and spray graffiti on it. I think thats what the
task is...

(I think the problems I'm having with my truss fuselage are tipping me
over the edge :-) ohhhhhh bugger column bending. why cant you just
build things heavy )

Stealth (it looked easy) Pilot

[Morgans[_7_]]

"Stealth Pilot" > wrote
>
> (I think the problems I'm having with my truss fuselage are tipping me
> over the edge :-) ohhhhhh bugger column bending. why cant you just
> build things heavy )

Are you working on your Tailwind aeroplane, or a different project?
--
Jim in NC

[Anthony W]

Stealth Pilot wrote:
> I'm a lousy dentist.
> what's the project?
>
> Stealth Pilot

I'm converting auto electronic ignition parts for use on old
motorcycles. I will be making a reluctor to replace the points cam,
backing plates and mounts for the pickups.

Tony

[Peter Dohm]

"Stealth Pilot" > wrote in message
...
-------------much snipped-----------
> but you hafta admit that aerospace has way cooler x-prizes.
> there is one for a home made space vehicle plonked on the moon with a
> home made rocket. you hafta remotely drive up to some expensive nasa
> thingy on the moon and spray graffiti on it. I think thats what the
> task is...
>
> (I think the problems I'm having with my truss fuselage are tipping me
> over the edge :-)
Tthat does seem just remotely possible... :-) :-) ;_)

Peter

[Veeduber[_3_]]

On Aug 17, 3:19*pm, Anthony W > wrote:>
.. *I will be making a reluctor to replace the points cam,
> backing plates and mounts for the pickups.
> ----------------------------------------------------------------------------------------------

Dear Tony,

Please don't read this the wrong way...

After introduction of Hall Effect transistorized switches in the
1960's I spent two years developing an ignition system which used such
switches to replace the points on VW ignition systems. By the time I
had it perfected it was available as a plug-in module for about
$50 :-)

Mentioned here because magnetic reluctor triggering was one of the
methods I considered and discarded.

-------------------------------------------------------

Since you are working with motorcycle-scale components the odds are
that a small lathe will do about as well as a large one. I've a 7x10
that is more than large enough to let kids help their grandpa. These
are real parts (valve guides) turned out by real kids, who are
learning on a real lathe. It just happens to be quite a bit smaller
than the one grandpa is using.

In my opinion, you need to be wary of lathes & mills that are
CONVERTED to CNC. There are now a couple of small mills that are
designed for CNC from the ground up. Not sure where I saw them... in
one of the trade journals. As I recall their pricing reflected their
origins, which seems fair: I've never found any 'bargain' tools that
were worth a damn.

-R.S.Hoover

[Stealth Pilot[_2_]]

On Mon, 17 Aug 2009 19:04:51 -0700 (PDT), Veeduber
> wrote:


>Since you are working with motorcycle-scale components the odds are
>that a small lathe will do about as well as a large one. I've a 7x10
>that is more than large enough to let kids help their grandpa. These
>are real parts (valve guides) turned out by real kids, who are
>learning on a real lathe. It just happens to be quite a bit smaller
>than the one grandpa is using.
>
lotsa good work is done on a Taig.

: I've never found any 'bargain' tools that
>were worth a damn.
>
>-R.S.Hoover

ditto. while I have a chinese mill that performs flawlessly chinese
tooling is crap. mainly because the alloy the component is made from
is never the correct or optimum alloy for the part.

drill bits, insert cutters, milling cutters made in china are just
utter crap quality. they wear out at an astonishing rate.
buying any of them is an absolute waste of money.

I relented a while ago and bought a chinese tap and die set to do a
job needing 12" unc. I have to admit that the die produced an
absolutely schmick thread ....but it was a full millimeter under
diameter. it was bloody hard to screw on too.

my vermont american tap and die set in UNF has never failed me for
aviation work.

the 1/2"unc was for a screw trim adjuster on a sonerai. the Sutton
(Australian) tap and die produced flawlessly mating threads of the
correct diameter.

btw Anthony an old lathe like a South Bend, if it is good condition is
a very good buy. my own lathe is a Hercus clone of the southbend
produced just after the second world war. it wouldnt pass an occ.
health and safety audit because of the exposed V belts but it is
absolutely superb for the aviation machining I do.

Stealth Pilot

[Stealth Pilot[_2_]]

On Mon, 17 Aug 2009 14:11:58 -0400, "Morgans"
> wrote:

>
>"Stealth Pilot" > wrote
>>
>> (I think the problems I'm having with my truss fuselage are tipping me
>> over the edge :-) ohhhhhh bugger column bending. why cant you just
>> build things heavy )
>
>Are you working on your Tailwind aeroplane, or a different project?

eventually I will get and do a reverse engineer of the Tailwind.
mine is 25 years/680 hours old so I dont think there is too much to
worry about.

the current project is a single seat taildragger ultralight as a
learning tool. I accidently hit a shape/layout for a very conventional
design that has superb weight and balance figures so I've been
motivated to work the design to completion and build one.

persistence is the key to success in aviation and structural design.
trouble is it makes you feel so bloody dumb while you are persisting
through the learning difficulties. :-)

if it wasnt for the patience of a very schmicked up aero engineer I
think I'd be screwed. the japanese have a saying "so much data so
little understanding." my years of reading have represented just so
much data! my friend's understanding and crystal clear insight is
making this happen, slowly.

btw Jim. I have a computed drag curve for the tailwind. you will know
the classic diagram of induced and parasitic drag that has induced
reducing in a curve to nothing while parasitic increases in a curve to
maximum. the plot of resultant drag sits above the crossed lines as a
U shape. it's a classic representation.
for the W8 tailwind that classic U shape is centred on 80 knots.
what that means is that on approach if you slow down to 60 knots you
get in the area of rapidly increasing sink (which is why you approach
at 70 knots) you havent just entered the "back side of the drag
curve", you've always been in it. At 65 knots you are entering the
vertical part of the left side of the U. at 70 knots you are at the
bottom left corner. tailwinds *are* happiest flying fast.

Stealth Pilot

[Dan[_12_]]

Stealth Pilot wrote:
> On Mon, 17 Aug 2009 19:04:51 -0700 (PDT), Veeduber
> > wrote:
>
>
>> Since you are working with motorcycle-scale components the odds are
>> that a small lathe will do about as well as a large one. I've a 7x10
>> that is more than large enough to let kids help their grandpa. These
>> are real parts (valve guides) turned out by real kids, who are
>> learning on a real lathe. It just happens to be quite a bit smaller
>> than the one grandpa is using.
>>
> lotsa good work is done on a Taig.
>
> : I've never found any 'bargain' tools that
>> were worth a damn.
>>
>> -R.S.Hoover
>
> ditto. while I have a chinese mill that performs flawlessly chinese
> tooling is crap. mainly because the alloy the component is made from
> is never the correct or optimum alloy for the part.
>
> drill bits, insert cutters, milling cutters made in china are just
> utter crap quality. they wear out at an astonishing rate.
> buying any of them is an absolute waste of money.
>
> I relented a while ago and bought a chinese tap and die set to do a
> job needing 12" unc. I have to admit that the die produced an
> absolutely schmick thread ....but it was a full millimeter under
> diameter. it was bloody hard to screw on too.
>
> my vermont american tap and die set in UNF has never failed me for
> aviation work.
>
> the 1/2"unc was for a screw trim adjuster on a sonerai. the Sutton
> (Australian) tap and die produced flawlessly mating threads of the
> correct diameter.
>
> btw Anthony an old lathe like a South Bend, if it is good condition is
> a very good buy. my own lathe is a Hercus clone of the southbend
> produced just after the second world war. it wouldnt pass an occ.
> health and safety audit because of the exposed V belts but it is
> absolutely superb for the aviation machining I do.
>
> Stealth Pilot

A few years ago I bought a Chinese metric tap and die set to fill
the gaps in my collection. The tap handle was nice. I'd sure like to
know to what standard the taps and dies were made. The finish was rough
and the dimensions were wrong. I kept the tap handle.

One of the drawbacks to owning Huot dispensers for mills, taps,
drills, reamers etc is one is aware of sizes one doesn't have. Once in
awhile I fill the empty slots knowing full well I may never use those
particular tools.

Dan, U.S. Air Force, retired

[Anthony W]

Stealth Pilot wrote:
> btw Anthony an old lathe like a South Bend, if it is good condition is
> a very good buy. my own lathe is a Hercus clone of the southbend
> produced just after the second world war. it wouldnt pass an occ.
> health and safety audit because of the exposed V belts but it is
> absolutely superb for the aviation machining I do.
>
> Stealth Pilot

You won't find a good used South Bend lathe around here or at least not
what I've seen. By the time they come up for sale, they're more than a
little worn out.

Tony

[Peter Dohm]

"Stealth Pilot" > wrote in message
...
> On Mon, 17 Aug 2009 14:11:58 -0400, "Morgans"
> > wrote:
>
>>
>>"Stealth Pilot" > wrote
>>>
>>> (I think the problems I'm having with my truss fuselage are tipping me
>>> over the edge :-) ohhhhhh bugger column bending. why cant you just
>>> build things heavy )
>>
>>Are you working on your Tailwind aeroplane, or a different project?
>
> eventually I will get and do a reverse engineer of the Tailwind.
> mine is 25 years/680 hours old so I dont think there is too much to
> worry about.
>
> the current project is a single seat taildragger ultralight as a
> learning tool. I accidently hit a shape/layout for a very conventional
> design that has superb weight and balance figures so I've been
> motivated to work the design to completion and build one.
>
> persistence is the key to success in aviation and structural design.
> trouble is it makes you feel so bloody dumb while you are persisting
> through the learning difficulties. :-)
>
> if it wasnt for the patience of a very schmicked up aero engineer I
> think I'd be screwed. the japanese have a saying "so much data so
> little understanding."

To my eye, this looks like either a German or French saying; but I suppose
that many others will recognize it as their own as well. (In some business
oriented groups, the related saying is: "paralysis by analysis."


my years of reading have represented just so
> much data! my friend's understanding and crystal clear insight is
> making this happen, slowly.
>
> btw Jim. I have a computed drag curve for the tailwind. you will know
> the classic diagram of induced and parasitic drag that has induced
> reducing in a curve to nothing while parasitic increases in a curve to
> maximum. the plot of resultant drag sits above the crossed lines as a
> U shape. it's a classic representation.
> for the W8 tailwind that classic U shape is centred on 80 knots.
> what that means is that on approach if you slow down to 60 knots you
> get in the area of rapidly increasing sink (which is why you approach
> at 70 knots) you havent just entered the "back side of the drag
> curve", you've always been in it. At 65 knots you are entering the
> vertical part of the left side of the U. at 70 knots you are at the
> bottom left corner. tailwinds *are* happiest flying fast.
>
> Stealth Pilot

The tailwind is amoung the all time standouts in low parasitic drag, and the
rapid rise of induced drag above the stall contributes to the short field
landing performance. I lack any personal experience, but have been told
that the short field performance is excellent.

Peter

[Stu Fields]

"Peter Dohm" > wrote in message
...
> "Stealth Pilot" > wrote in message
> ...
>> On Mon, 17 Aug 2009 14:11:58 -0400, "Morgans"
>> > wrote:
>>
>>>
>>>"Stealth Pilot" > wrote
>>>>
>>>> (I think the problems I'm having with my truss fuselage are tipping me
>>>> over the edge :-) ohhhhhh bugger column bending. why cant you just
>>>> build things heavy )
>>>
>>>Are you working on your Tailwind aeroplane, or a different project?
>>
>> eventually I will get and do a reverse engineer of the Tailwind.
>> mine is 25 years/680 hours old so I dont think there is too much to
>> worry about.
>>
>> the current project is a single seat taildragger ultralight as a
>> learning tool. I accidently hit a shape/layout for a very conventional
>> design that has superb weight and balance figures so I've been
>> motivated to work the design to completion and build one.
>>
>> persistence is the key to success in aviation and structural design.
>> trouble is it makes you feel so bloody dumb while you are persisting
>> through the learning difficulties. :-)
>>
>> if it wasnt for the patience of a very schmicked up aero engineer I
>> think I'd be screwed. the japanese have a saying "so much data so
>> little understanding."
>
> To my eye, this looks like either a German or French saying; but I suppose
> that many others will recognize it as their own as well. (In some
> business oriented groups, the related saying is: "paralysis by
> analysis."
>
>
> my years of reading have represented just so
>> much data! my friend's understanding and crystal clear insight is
>> making this happen, slowly.
>>
>> btw Jim. I have a computed drag curve for the tailwind. you will know
>> the classic diagram of induced and parasitic drag that has induced
>> reducing in a curve to nothing while parasitic increases in a curve to
>> maximum. the plot of resultant drag sits above the crossed lines as a
>> U shape. it's a classic representation.
>> for the W8 tailwind that classic U shape is centred on 80 knots.
>> what that means is that on approach if you slow down to 60 knots you
>> get in the area of rapidly increasing sink (which is why you approach
>> at 70 knots) you havent just entered the "back side of the drag
>> curve", you've always been in it. At 65 knots you are entering the
>> vertical part of the left side of the U. at 70 knots you are at the
>> bottom left corner. tailwinds *are* happiest flying fast.
>>
>> Stealth Pilot
>
> The tailwind is amoung the all time standouts in low parasitic drag, and
> the rapid rise of induced drag above the stall contributes to the short
> field landing performance. I lack any personal experience, but have been
> told that the short field performance is excellent.
>
> Peter

Peter another that I found during my stint with DoD. "Get the money spent.
We can find out what we did wrong later."

[Stealth Pilot[_2_]]

On Wed, 19 Aug 2009 14:07:24 -0400, "Peter Dohm"
> wrote:

>"Stealth Pilot" > wrote in message
...
>> On Mon, 17 Aug 2009 14:11:58 -0400, "Morgans"
>> > wrote:
>>
>>>

>> btw Jim. I have a computed drag curve for the tailwind. you will know
>> the classic diagram of induced and parasitic drag that has induced
>> reducing in a curve to nothing while parasitic increases in a curve to
>> maximum. the plot of resultant drag sits above the crossed lines as a
>> U shape. it's a classic representation.
>> for the W8 tailwind that classic U shape is centred on 80 knots.
>> what that means is that on approach if you slow down to 60 knots you
>> get in the area of rapidly increasing sink (which is why you approach
>> at 70 knots) you havent just entered the "back side of the drag
>> curve", you've always been in it. At 65 knots you are entering the
>> vertical part of the left side of the U. at 70 knots you are at the
>> bottom left corner. tailwinds *are* happiest flying fast.
>>
>> Stealth Pilot
>
>The tailwind is amoung the all time standouts in low parasitic drag, and the
>rapid rise of induced drag above the stall contributes to the short field
>landing performance. I lack any personal experience, but have been told
>that the short field performance is excellent.
>
>Peter
>

if you want to really impress the pundits in a Tailwind.
you give it the gun, tail up and hold it there. normally Takeoff
Safety Speed is 57 knots but the tyres are rated to 120 knots, so you
accelerate holding it on until 80 knots. you do this solo btw.
then as you pass through 80 knots with full throttle you gently but
firmly rotate into a steep climb. you can hold this to 250ft
thereabouts at which time you bunt back to a more gentle takeoff
profile.

what the pundits see from the ground is just an apparently normal
takeoff, the speed differences not being that noticeable.
the climb out though would beat the pants of any damned ultralight!

the original builder of my aircraft was sitting beside our clubhouse
one day chatting when I did this. he was utterly stunned that the
tailwind had such dynamic takeoff performance.
"oh you made my day. she went up like a homesick angel"

....it is all technique born of knowledge.
I've owned the W8 Tailwind now for 10 years and I wouldnt trade it for
the world. once you get used to them they are a magic aeroplane.

landing speed I have no idea on. you never never never look inside the
cockpit during flare out. never.
on grass I'm stopped half way along a 600m strip most of the time.
Stealth Pilot