Machining Characteristics of Plastics
 

I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

I don't know if this CO. has any bushings the size your looking for. But
you may want to check
http://www.apfp.com/pdf/spacers.pdf

Jack
"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

I don't know if this CO. has any bushings the size your looking for. But
you may want to check
http://www.apfp.com/pdf/spacers.pdf

Jack
"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

UHMW is my choice for just about everything. You wouldn't need the self
lubricating charicteristics for what you are doing. Nylon would work fine.

Neither one has any UV inhibitors though.. I'm not sure which other plastics
might have this.. If your fitting is mostly enclosed then UV wouldn't be a
factor. (my Aries windvane has nylon bearings and spacers but only the edges
have deteriorated over 25 years of exposure).

Nylon machines cleaner than UHMW but both can be frustrating to achieve an
acurate final dimension because of the flex and give.. This can be overcome
by using a modified tool angle, etc. I'm not a machinist so I just
experiment with this..

A fine finish is very difficult to achieve on UHMW.. You can't file or sand
it.. A sharp tool and a slow feed will help.

In the end, for bushings, this stuff is great and even if you do a sloppy
job of machining, you can just split the bushing and use clamping force to
adjust the clearance/fit.

If you don't have access to a lathe or milling machine, you can still do a
lot in a drill press.. I use Forstner bits for a nice clean hole of the
larger sizes. I have also use hole saws to rough out holes.

The UHMW is easy to tape/thread and if your part is thick enough, the
fasteners hold very well. It would be difficult to measure final torque with
this material and I suspect you could strip threads if your not careful.


--
My opinion and experience. FWIW

Steve
s/v Good Intentions

Machining Characteristics of Plastics
 

UHMW is my choice for just about everything. You wouldn't need the self
lubricating charicteristics for what you are doing. Nylon would work fine.

Neither one has any UV inhibitors though.. I'm not sure which other plastics
might have this.. If your fitting is mostly enclosed then UV wouldn't be a
factor. (my Aries windvane has nylon bearings and spacers but only the edges
have deteriorated over 25 years of exposure).

Nylon machines cleaner than UHMW but both can be frustrating to achieve an
acurate final dimension because of the flex and give.. This can be overcome
by using a modified tool angle, etc. I'm not a machinist so I just
experiment with this..

A fine finish is very difficult to achieve on UHMW.. You can't file or sand
it.. A sharp tool and a slow feed will help.

In the end, for bushings, this stuff is great and even if you do a sloppy
job of machining, you can just split the bushing and use clamping force to
adjust the clearance/fit.

If you don't have access to a lathe or milling machine, you can still do a
lot in a drill press.. I use Forstner bits for a nice clean hole of the
larger sizes. I have also use hole saws to rough out holes.

The UHMW is easy to tape/thread and if your part is thick enough, the
fasteners hold very well. It would be difficult to measure final torque with
this material and I suspect you could strip threads if your not careful.


--
My opinion and experience. FWIW

Steve
s/v Good Intentions

Machining Characteristics of Plastics
 

You might try www.mcmaster.com as an alternate to mscdirect. They have good
descriptions of all the plastics.

As far as choice of plastic, they'll all work. They mostly tend to catch a
little more than steel in the lathe -- more like copper, but you should have
no problem on a metal lathe. On a wood lathe, I suspect you'll have to be
very careful with tool angle -- closer to a scrape than a cut, but I'm not
sure as I haven't used a wood lathe in years -- you get lazy with a metal
lathe in house -- just set it up and go, even in wood.

Go with black (this is a little counter-intuitive as the black soaks up the
IR and gets hotter, but it keeps the UV out of the material).

If you need to glue it, pay attention, 'cause some of these don't like
gluing, especially HDPE.


--
Jim Woodward
www.mvFintry.com


..
"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

You might try www.mcmaster.com as an alternate to mscdirect. They have good
descriptions of all the plastics.

As far as choice of plastic, they'll all work. They mostly tend to catch a
little more than steel in the lathe -- more like copper, but you should have
no problem on a metal lathe. On a wood lathe, I suspect you'll have to be
very careful with tool angle -- closer to a scrape than a cut, but I'm not
sure as I haven't used a wood lathe in years -- you get lazy with a metal
lathe in house -- just set it up and go, even in wood.

Go with black (this is a little counter-intuitive as the black soaks up the
IR and gets hotter, but it keeps the UV out of the material).

If you need to glue it, pay attention, 'cause some of these don't like
gluing, especially HDPE.


--
Jim Woodward
www.mvFintry.com


..
"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

McMaster has the same material plus PVC. Any will do but I would go for
Acetal (Delrin) for the strength and UV resistance. For any of them the
tooling should have a positive rake and plenty of relief. The bit
should also be polished as well as possible. Plastics don't disburse
heat as well as metals so you don't want anything draging on the
surface. Turning and drilling are done at about 600 fpm and feed about
..010 to .015. Depth of cut can be pretty heavy but I don't get as good
a finish with fine cuts so plan your last pass carefully to take off at
least .02". Keep in mind that plastics expand a lot more than metal
when they heat up and deflect more under pressure of the bit. The two
factors combined make getting high tolerances right tricky. Mill to a
few thou over size and let it cool before measuring. Then take the last
couple of passes.

When it is cutting correctly acetal does not produce chips. It makes
one long ribbon that piles up on the bit and the part. You have to keep
pulling it away or it will snag on the bit and cause a rough spot.

For Delrin AF and nylons, increase the speed to about 700 fps and cut
back the feed to .007 max.

Boedeker has a pretty good page on machining plastics
http://www.boedeker.com/fabtip.htm

Geoffrey W. Schultz wrote:

I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength of
these would be greatly appreciated.

-- Geoff

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Machining Characteristics of Plastics
 

McMaster has the same material plus PVC. Any will do but I would go for
Acetal (Delrin) for the strength and UV resistance. For any of them the
tooling should have a positive rake and plenty of relief. The bit
should also be polished as well as possible. Plastics don't disburse
heat as well as metals so you don't want anything draging on the
surface. Turning and drilling are done at about 600 fpm and feed about
..010 to .015. Depth of cut can be pretty heavy but I don't get as good
a finish with fine cuts so plan your last pass carefully to take off at
least .02". Keep in mind that plastics expand a lot more than metal
when they heat up and deflect more under pressure of the bit. The two
factors combined make getting high tolerances right tricky. Mill to a
few thou over size and let it cool before measuring. Then take the last
couple of passes.

When it is cutting correctly acetal does not produce chips. It makes
one long ribbon that piles up on the bit and the part. You have to keep
pulling it away or it will snag on the bit and cause a rough spot.

For Delrin AF and nylons, increase the speed to about 700 fps and cut
back the feed to .007 max.

Boedeker has a pretty good page on machining plastics
http://www.boedeker.com/fabtip.htm

Geoffrey W. Schultz wrote:

I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength of
these would be greatly appreciated.

-- Geoff

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Machining Characteristics of Plastics
 

..
"Glenn Ashmore" wrote in message
news:_m8sb.15172$62.3195@lakeread04...

SNIP

Boedeker has a pretty good page on machining plastics
http://www.boedeker.com/fabtip.htm

snip

Once again I'm amazed at the depths of Glenn"s bookmarks. I wonder if it
would be useful for us to make available our bookmarks to each other? Post
them on rbb? Or would that take away all the mystery?


--
Jim Woodward
www.mvFintry.com

Machining Characteristics of Plastics
 

..
"Glenn Ashmore" wrote in message
news:_m8sb.15172$62.3195@lakeread04...

SNIP

Boedeker has a pretty good page on machining plastics
http://www.boedeker.com/fabtip.htm

snip

Once again I'm amazed at the depths of Glenn"s bookmarks. I wonder if it
would be useful for us to make available our bookmarks to each other? Post
them on rbb? Or would that take away all the mystery?


--
Jim Woodward
www.mvFintry.com

Machining Characteristics of Plastics
 

My bookmarks are so disorganized that I wish there was something like
google to search them. I have everything from thermodynamic formulas
for steam engines to how to make springs to the Forest Products Lab
encyclobedia of woods and timber production. From the Billboard top 50
archive to NPR's essential library of classical music.

What was that old Heinlein quote? "A man should be able to change a
diaper, plan an invasion, butcher a hog, sail a ship, design a building,
write a sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve equations,
analyse a problem, pitch manure, program a computer, cook a tasty meal,
fight efficiently and die gallantly. Specialisation is for insects."

I may not be able to do them all but I can find out how somewhere in my
bookmarks. :-)

Jim Woodward wrote:
.
"Glenn Ashmore" wrote in message
news:_m8sb.15172$62.3195@lakeread04...

SNIP

Boedeker has a pretty good page on machining plastics
http://www.boedeker.com/fabtip.htm


snip

Once again I'm amazed at the depths of Glenn"s bookmarks. I wonder if it
would be useful for us to make available our bookmarks to each other? Post
them on rbb? Or would that take away all the mystery?



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Machining Characteristics of Plastics
 

My bookmarks are so disorganized that I wish there was something like
google to search them. I have everything from thermodynamic formulas
for steam engines to how to make springs to the Forest Products Lab
encyclobedia of woods and timber production. From the Billboard top 50
archive to NPR's essential library of classical music.

What was that old Heinlein quote? "A man should be able to change a
diaper, plan an invasion, butcher a hog, sail a ship, design a building,
write a sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve equations,
analyse a problem, pitch manure, program a computer, cook a tasty meal,
fight efficiently and die gallantly. Specialisation is for insects."

I may not be able to do them all but I can find out how somewhere in my
bookmarks. :-)

Jim Woodward wrote:
.
"Glenn Ashmore" wrote in message
news:_m8sb.15172$62.3195@lakeread04...

SNIP

Boedeker has a pretty good page on machining plastics
http://www.boedeker.com/fabtip.htm


snip

Once again I'm amazed at the depths of Glenn"s bookmarks. I wonder if it
would be useful for us to make available our bookmarks to each other? Post
them on rbb? Or would that take away all the mystery?



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Machining Characteristics of Plastics
 

I just want to thank everyone for their insight. Very helpful! Thanks a
lot!

-- Geoff

Machining Characteristics of Plastics
 

I just want to thank everyone for their insight. Very helpful! Thanks a
lot!

-- Geoff

Machining Characteristics of Plastics
 

Understood. Mine are in much the same state and are very revealing.

Tools Organize Favorites in IE6 is a joke -- really hard to use. I just
bookmark the exported form of the bookmarks list -- it's certainly easier to
see than the IE6 tree.

"thermodynamic formulas for steam engines"? Railroad steam?

Although I claim to be able to fix anything that isn't living (a little over
reaching), I draw the line at diapers and bones. Dee is a qualified Ship's
Medical Officer (Maine Maritime Academy) so I leave fixing the living to
her.


--
Jim Woodward
www.mvFintry.com


..
"Glenn Ashmore" wrote in message
news:wFbsb.16555$62.14104@lakeread04...
My bookmarks are so disorganized that I wish there was something like
google to search them. I have everything from thermodynamic formulas
for steam engines to how to make springs to the Forest Products Lab
encyclobedia of woods and timber production. From the Billboard top 50
archive to NPR's essential library of classical music.

What was that old Heinlein quote? "A man should be able to change a
diaper, plan an invasion, butcher a hog, sail a ship, design a building,
write a sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve equations,
analyse a problem, pitch manure, program a computer, cook a tasty meal,
fight efficiently and die gallantly. Specialisation is for insects."

I may not be able to do them all but I can find out how somewhere in my
bookmarks. :-)

Jim Woodward wrote:
.
"Glenn Ashmore" wrote in message
news:_m8sb.15172$62.3195@lakeread04...

SNIP

Boedeker has a pretty good page on machining plastics
http://www.boedeker.com/fabtip.htm


snip

Once again I'm amazed at the depths of Glenn"s bookmarks. I wonder if
it
would be useful for us to make available our bookmarks to each other?
Post
them on rbb? Or would that take away all the mystery?



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Machining Characteristics of Plastics
 

Understood. Mine are in much the same state and are very revealing.

Tools Organize Favorites in IE6 is a joke -- really hard to use. I just
bookmark the exported form of the bookmarks list -- it's certainly easier to
see than the IE6 tree.

"thermodynamic formulas for steam engines"? Railroad steam?

Although I claim to be able to fix anything that isn't living (a little over
reaching), I draw the line at diapers and bones. Dee is a qualified Ship's
Medical Officer (Maine Maritime Academy) so I leave fixing the living to
her.


--
Jim Woodward
www.mvFintry.com


..
"Glenn Ashmore" wrote in message
news:wFbsb.16555$62.14104@lakeread04...
My bookmarks are so disorganized that I wish there was something like
google to search them. I have everything from thermodynamic formulas
for steam engines to how to make springs to the Forest Products Lab
encyclobedia of woods and timber production. From the Billboard top 50
archive to NPR's essential library of classical music.

What was that old Heinlein quote? "A man should be able to change a
diaper, plan an invasion, butcher a hog, sail a ship, design a building,
write a sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve equations,
analyse a problem, pitch manure, program a computer, cook a tasty meal,
fight efficiently and die gallantly. Specialisation is for insects."

I may not be able to do them all but I can find out how somewhere in my
bookmarks. :-)

Jim Woodward wrote:
.
"Glenn Ashmore" wrote in message
news:_m8sb.15172$62.3195@lakeread04...

SNIP

Boedeker has a pretty good page on machining plastics
http://www.boedeker.com/fabtip.htm


snip

Once again I'm amazed at the depths of Glenn"s bookmarks. I wonder if
it
would be useful for us to make available our bookmarks to each other?
Post
them on rbb? Or would that take away all the mystery?



--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Machining Characteristics of Plastics
 

What kind of speeds are producing this effect? My KISS doesn't
produce any significant vibration up to 30 kts or so. That is as fast
as I have run it. Have you checked the balance of the blades? A
slight unbalance in the blades might induce a vibration in the
mounting. I chose to use 2" SS tube rather than sched 40 pipe. The
PVC fitting is a snug fit. The KISS came with an assortment of
fittings to fit a number of different kinds of pipe. If the 2" tube fits
the KISS better than the sched 40 pipe, perhaps attaching a short
length of 2" tube to the top of the pipe for mounting would be a
simpler solution.

Doug
s/v Callista

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

What kind of speeds are producing this effect? My KISS doesn't
produce any significant vibration up to 30 kts or so. That is as fast
as I have run it. Have you checked the balance of the blades? A
slight unbalance in the blades might induce a vibration in the
mounting. I chose to use 2" SS tube rather than sched 40 pipe. The
PVC fitting is a snug fit. The KISS came with an assortment of
fittings to fit a number of different kinds of pipe. If the 2" tube fits
the KISS better than the sched 40 pipe, perhaps attaching a short
length of 2" tube to the top of the pipe for mounting would be a
simpler solution.

Doug
s/v Callista

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

Go over to rec.crafts.metalworking and post your question there. While the
group is nominally about metalworking, the machinists there know a lot about
the machining characteristics of various materials like the plastics.

Tom Dacon

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

Go over to rec.crafts.metalworking and post your question there. While the
group is nominally about metalworking, the machinists there know a lot about
the machining characteristics of various materials like the plastics.

Tom Dacon

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

It's definately a blade balance issue, but I've carefully run through
the balancing instructions and I can't find any blade that's heavier
than the others. I'm sure that there are some harmonics that are
causing it, but I haven't been able to figure out how to balance it.

None of the PVC fittings that came with it provided what I would call a
snug fit. There was a good 1/16" clearance around the pipe, which
certainly is enough to allow vibration.

-- Geoff


"Doug Dotson" wrote in
:

What kind of speeds are producing this effect? My KISS doesn't
produce any significant vibration up to 30 kts or so. That is as fast
as I have run it. Have you checked the balance of the blades? A
slight unbalance in the blades might induce a vibration in the
mounting. I chose to use 2" SS tube rather than sched 40 pipe. The
PVC fitting is a snug fit. The KISS came with an assortment of
fittings to fit a number of different kinds of pipe. If the 2" tube
fits the KISS better than the sched 40 pipe, perhaps attaching a short
length of 2" tube to the top of the pipe for mounting would be a
simpler solution.

Doug
s/v Callista

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall
strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

It's definately a blade balance issue, but I've carefully run through
the balancing instructions and I can't find any blade that's heavier
than the others. I'm sure that there are some harmonics that are
causing it, but I haven't been able to figure out how to balance it.

None of the PVC fittings that came with it provided what I would call a
snug fit. There was a good 1/16" clearance around the pipe, which
certainly is enough to allow vibration.

-- Geoff


"Doug Dotson" wrote in
:

What kind of speeds are producing this effect? My KISS doesn't
produce any significant vibration up to 30 kts or so. That is as fast
as I have run it. Have you checked the balance of the blades? A
slight unbalance in the blades might induce a vibration in the
mounting. I chose to use 2" SS tube rather than sched 40 pipe. The
PVC fitting is a snug fit. The KISS came with an assortment of
fittings to fit a number of different kinds of pipe. If the 2" tube
fits the KISS better than the sched 40 pipe, perhaps attaching a short
length of 2" tube to the top of the pipe for mounting would be a
simpler solution.

Doug
s/v Callista

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall
strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Tue, 11 Nov 2003 15:23:37 -0500,
Glenn Ashmore wrote:
My bookmarks are so disorganized that I wish there was something like
google to search them. I have everything from thermodynamic formulas
for steam engines to how to make springs to the Forest Products Lab
encyclobedia of woods and timber production. From the Billboard top 50
archive to NPR's essential library of classical music.

What was that old Heinlein quote? "A man should be able to change a
diaper, plan an invasion, butcher a hog, sail a ship, design a building,
write a sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve equations,
analyse a problem, pitch manure, program a computer, cook a tasty meal,
fight efficiently and die gallantly. Specialisation is for insects."

I may not be able to do them all but I can find out how somewhere in my
bookmarks. :-)

Jim Woodward wrote:



Try Mozilla, you can search the bookmarks, in the manage bookmarks mode.
Search on URL, name, descriptin, keywords. You can even save the search
terms as a bookmark. :) This makes dealing with hundreds of bookmarks
(no, that's not a typo...) possible for me.

Of course, you can also export them as tags, and grep through that, but
that's a little more work.

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.3 (GNU/Linux)

iD8DBQE/sguMd90bcYOAWPYRAn5BAJ9rc3emjrltzh4f0d2CIhFGDz0Elw CdE70i
lNpkASEtZFMQISAm2k6l6Qw=
=BadB
-----END PGP SIGNATURE-----

--
Jim Richardson http://www.eskimo.com/~warlock
Orwell and Roddenberry weren't just writers, they were prophets.

Machining Characteristics of Plastics
 

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Tue, 11 Nov 2003 15:23:37 -0500,
Glenn Ashmore wrote:
My bookmarks are so disorganized that I wish there was something like
google to search them. I have everything from thermodynamic formulas
for steam engines to how to make springs to the Forest Products Lab
encyclobedia of woods and timber production. From the Billboard top 50
archive to NPR's essential library of classical music.

What was that old Heinlein quote? "A man should be able to change a
diaper, plan an invasion, butcher a hog, sail a ship, design a building,
write a sonnet, balance accounts, build a wall, set a bone, comfort the
dying, take orders, give orders, cooperate, act alone, solve equations,
analyse a problem, pitch manure, program a computer, cook a tasty meal,
fight efficiently and die gallantly. Specialisation is for insects."

I may not be able to do them all but I can find out how somewhere in my
bookmarks. :-)

Jim Woodward wrote:



Try Mozilla, you can search the bookmarks, in the manage bookmarks mode.
Search on URL, name, descriptin, keywords. You can even save the search
terms as a bookmark. :) This makes dealing with hundreds of bookmarks
(no, that's not a typo...) possible for me.

Of course, you can also export them as tags, and grep through that, but
that's a little more work.

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.3 (GNU/Linux)

iD8DBQE/sguMd90bcYOAWPYRAn5BAJ9rc3emjrltzh4f0d2CIhFGDz0Elw CdE70i
lNpkASEtZFMQISAm2k6l6Qw=
=BadB
-----END PGP SIGNATURE-----

--
Jim Richardson http://www.eskimo.com/~warlock
Orwell and Roddenberry weren't just writers, they were prophets.

Machining Characteristics of Plastics
 

Use a high speed bit with a lot of rake,and hone the point to about .010"
radius.UHMW and nylon will machine like butter,and do fine.

Benny
S/V Panacea

Machining Characteristics of Plastics
 

Use a high speed bit with a lot of rake,and hone the point to about .010"
radius.UHMW and nylon will machine like butter,and do fine.

Benny
S/V Panacea

Machining Characteristics of Plastics
 

The 2" tubing gives is good fit and since it is polished to a high
finish, it swivels nice and smooth. I was originally going to use
sched 40 pipe but the guy at the stainless place (KATO Marine
in Annapolis) talked me out of it. Said sched 40 pipe was very
heavy and cost 3x what the tubing did. Also, the tubing is polished
to a high luster so it looks really nice. As I suggested earlier, it
might be good just to have a 6" piece of tube welded onto the
top of the pole. The instructions said that the PVC collar would
have to be slightly enlarged to accomodate the tube, but that
turned out not to be the case. 2 collars were provided, one fit
the tube perfectly.

Doug

"Geoffrey W. Schultz" wrote in message
.17...
It's definately a blade balance issue, but I've carefully run through
the balancing instructions and I can't find any blade that's heavier
than the others. I'm sure that there are some harmonics that are
causing it, but I haven't been able to figure out how to balance it.

None of the PVC fittings that came with it provided what I would call a
snug fit. There was a good 1/16" clearance around the pipe, which
certainly is enough to allow vibration.

-- Geoff


"Doug Dotson" wrote in
:

What kind of speeds are producing this effect? My KISS doesn't
produce any significant vibration up to 30 kts or so. That is as fast
as I have run it. Have you checked the balance of the blades? A
slight unbalance in the blades might induce a vibration in the
mounting. I chose to use 2" SS tube rather than sched 40 pipe. The
PVC fitting is a snug fit. The KISS came with an assortment of
fittings to fit a number of different kinds of pipe. If the 2" tube
fits the KISS better than the sched 40 pipe, perhaps attaching a short
length of 2" tube to the top of the pipe for mounting would be a
simpler solution.

Doug
s/v Callista

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall
strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

The 2" tubing gives is good fit and since it is polished to a high
finish, it swivels nice and smooth. I was originally going to use
sched 40 pipe but the guy at the stainless place (KATO Marine
in Annapolis) talked me out of it. Said sched 40 pipe was very
heavy and cost 3x what the tubing did. Also, the tubing is polished
to a high luster so it looks really nice. As I suggested earlier, it
might be good just to have a 6" piece of tube welded onto the
top of the pole. The instructions said that the PVC collar would
have to be slightly enlarged to accomodate the tube, but that
turned out not to be the case. 2 collars were provided, one fit
the tube perfectly.

Doug

"Geoffrey W. Schultz" wrote in message
.17...
It's definately a blade balance issue, but I've carefully run through
the balancing instructions and I can't find any blade that's heavier
than the others. I'm sure that there are some harmonics that are
causing it, but I haven't been able to figure out how to balance it.

None of the PVC fittings that came with it provided what I would call a
snug fit. There was a good 1/16" clearance around the pipe, which
certainly is enough to allow vibration.

-- Geoff


"Doug Dotson" wrote in
:

What kind of speeds are producing this effect? My KISS doesn't
produce any significant vibration up to 30 kts or so. That is as fast
as I have run it. Have you checked the balance of the blades? A
slight unbalance in the blades might induce a vibration in the
mounting. I chose to use 2" SS tube rather than sched 40 pipe. The
PVC fitting is a snug fit. The KISS came with an assortment of
fittings to fit a number of different kinds of pipe. If the 2" tube
fits the KISS better than the sched 40 pipe, perhaps attaching a short
length of 2" tube to the top of the pipe for mounting would be a
simpler solution.

Doug
s/v Callista

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall
strength
of
these would be greatly appreciated.

-- Geoff

Machining Characteristics of Plastics
 

On Tue, 11 Nov 2003 14:45:26 GMT, "Geoffrey W. Schultz"
wrote:


Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength of
these would be greatly appreciated.

I have limited experience in the others but like Delrin (Acetal). It
is very durable, easy to work with (for an amateur like me), and is
easy to get a good finish on in a machine. It is also available in
versions with very good UV resistibility, much better than Nylon.

http://plastics.dupont.com/NASApp/my...0&locale=en_US

http://www.sdplastics.com/ultravioletresistance.html



/Marcus

--
Marcus AAkesson
Gothenburg Callsigns: SM6XFN & SB4779
Sweden
Keep the world clean - no HTML in news or mail !

Machining Characteristics of Plastics
 

On Tue, 11 Nov 2003 14:45:26 GMT, "Geoffrey W. Schultz"
wrote:


Nylon
Acetal
UHMW
LDPE
HDPE

Comments on the machining qualities, UV resistance, and overall strength of
these would be greatly appreciated.

I have limited experience in the others but like Delrin (Acetal). It
is very durable, easy to work with (for an amateur like me), and is
easy to get a good finish on in a machine. It is also available in
versions with very good UV resistibility, much better than Nylon.

http://plastics.dupont.com/NASApp/my...0&locale=en_US

http://www.sdplastics.com/ultravioletresistance.html



/Marcus

--
Marcus AAkesson
Gothenburg Callsigns: SM6XFN & SB4779
Sweden
Keep the world clean - no HTML in news or mail !

Machining Characteristics of Plastics
 

Once again Glenn comes up with the winning response in a later
message. The only thing I'll add is that nylon is moisture sensitive.
It absorbs moisture easily and expands with moisture content (at
least when compared to most other plastics).

If you are looking at something like a tight fitting sleeve bushing then
I'd avoid nylon and use acetal or UHMW.

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Machining Characteristics of Plastics
 

Once again Glenn comes up with the winning response in a later
message. The only thing I'll add is that nylon is moisture sensitive.
It absorbs moisture easily and expands with moisture content (at
least when compared to most other plastics).

If you are looking at something like a tight fitting sleeve bushing then
I'd avoid nylon and use acetal or UHMW.

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a 2"
stainless schedule 40 support pipe that is loose fitting. I want to
machine one with a sleeve bearing on a lathe and make it out of plastic.
However, I really don't have any experience machining plastic, I've been
looking at www.mscdirect.com under Raw Materials/Plastic Material/Rods for
3" material. To keep costs under control I'm looking at the following:

Machining Characteristics of Plastics
 

Based upon input from this forum, rec.crafts.metalworking and all of the
pointers that were provided, I decided to go with black UHMW. As
described on some web sites it's the "poor man's teflon" with a very low
coefficient of friction, good UV stability and machines well. On top of
that, a 3"x1' piece of rod UHMW is only $11. I ordered it yesterday
from MSC and it'll be here today.

I've opted to simply machine the UHMW to form the sleave bearing surface
rather than purchase a sleave bearing and mount it in the housing. I'll
let you know how it turns out,

Thanks again for all of the help!

-- Geoff

"Matt/Meribeth Pedersen" wrote in
nk.net:

Once again Glenn comes up with the winning response in a later
message. The only thing I'll add is that nylon is moisture sensitive.
It absorbs moisture easily and expands with moisture content (at
least when compared to most other plastics).

If you are looking at something like a tight fitting sleeve bushing
then I'd avoid nylon and use acetal or UHMW.

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Machining Characteristics of Plastics
 

Based upon input from this forum, rec.crafts.metalworking and all of the
pointers that were provided, I decided to go with black UHMW. As
described on some web sites it's the "poor man's teflon" with a very low
coefficient of friction, good UV stability and machines well. On top of
that, a 3"x1' piece of rod UHMW is only $11. I ordered it yesterday
from MSC and it'll be here today.

I've opted to simply machine the UHMW to form the sleave bearing surface
rather than purchase a sleave bearing and mount it in the housing. I'll
let you know how it turns out,

Thanks again for all of the help!

-- Geoff

"Matt/Meribeth Pedersen" wrote in
nk.net:

Once again Glenn comes up with the winning response in a later
message. The only thing I'll add is that nylon is moisture sensitive.
It absorbs moisture easily and expands with moisture content (at
least when compared to most other plastics).

If you are looking at something like a tight fitting sleeve bushing
then I'd avoid nylon and use acetal or UHMW.

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Machining Characteristics of Plastics
 

I have well equipped woodworking workshop.
Can I use those all machines to work with UHMW as well?
Adam
"Geoffrey W. Schultz" wrote in message
9.17...
Based upon input from this forum, rec.crafts.metalworking and all of the
pointers that were provided, I decided to go with black UHMW. As
described on some web sites it's the "poor man's teflon" with a very low
coefficient of friction, good UV stability and machines well. On top of
that, a 3"x1' piece of rod UHMW is only $11. I ordered it yesterday
from MSC and it'll be here today.

I've opted to simply machine the UHMW to form the sleave bearing surface
rather than purchase a sleave bearing and mount it in the housing. I'll
let you know how it turns out,

Thanks again for all of the help!

-- Geoff

"Matt/Meribeth Pedersen" wrote in
nk.net:

Once again Glenn comes up with the winning response in a later
message. The only thing I'll add is that nylon is moisture sensitive.
It absorbs moisture easily and expands with moisture content (at
least when compared to most other plastics).

If you are looking at something like a tight fitting sleeve bushing
then I'd avoid nylon and use acetal or UHMW.

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Machining Characteristics of Plastics
 

I have well equipped woodworking workshop.
Can I use those all machines to work with UHMW as well?
Adam
"Geoffrey W. Schultz" wrote in message
9.17...
Based upon input from this forum, rec.crafts.metalworking and all of the
pointers that were provided, I decided to go with black UHMW. As
described on some web sites it's the "poor man's teflon" with a very low
coefficient of friction, good UV stability and machines well. On top of
that, a 3"x1' piece of rod UHMW is only $11. I ordered it yesterday
from MSC and it'll be here today.

I've opted to simply machine the UHMW to form the sleave bearing surface
rather than purchase a sleave bearing and mount it in the housing. I'll
let you know how it turns out,

Thanks again for all of the help!

-- Geoff

"Matt/Meribeth Pedersen" wrote in
nk.net:

Once again Glenn comes up with the winning response in a later
message. The only thing I'll add is that nylon is moisture sensitive.
It absorbs moisture easily and expands with moisture content (at
least when compared to most other plastics).

If you are looking at something like a tight fitting sleeve bushing
then I'd avoid nylon and use acetal or UHMW.

"Geoffrey W. Schultz" wrote in message
. 16...
I have a KISS wind generator that develops vibration at certain wind
speeds. The problem is that there's a PVC fitting that goes over a
2" stainless schedule 40 support pipe that is loose fitting. I want
to machine one with a sleeve bearing on a lathe and make it out of
plastic. However, I really don't have any experience machining
plastic, I've been looking at www.mscdirect.com under Raw
Materials/Plastic Material/Rods for 3" material. To keep costs under
control I'm looking at the following:

Machining Characteristics of Plastics
 

Adam wrote:

I have well equipped woodworking workshop.
Can I use those all machines to work with UHMW as well?
Adam

Mostly you can. I have better luck with a tripple chip carbide tipped
blade made for non-ferous metals. It has less tendancy to melt the
plastic. Drilling is easy but getting any tolerance on a wood lathe
takes a Zin that I do not possess. That really requires the presision
of a metal lathe.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Machining Characteristics of Plastics
 

Adam wrote:

I have well equipped woodworking workshop.
Can I use those all machines to work with UHMW as well?
Adam

Mostly you can. I have better luck with a tripple chip carbide tipped
blade made for non-ferous metals. It has less tendancy to melt the
plastic. Drilling is easy but getting any tolerance on a wood lathe
takes a Zin that I do not possess. That really requires the presision
of a metal lathe.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

Machining Characteristics of Plastics
 

I have never really understood why anyone buys a wood lathe -- and I say
this only a little in jest.

Wood lathes are expensive, the good ones are heavy, but you still have to
hold the tool. A metal lathe of similar size, that's old and little tired
for precision metalworking, will sell for less money than a similar sized
wood lathe, but do precision woodwork and also pretty good metalwork.

I've had a 13" South Bend for years. It was born in the same year I was,
1943, and is definitely not a production machine, but it does work that's
just fine for most boat purposes. The bed is only 48", which means that it
will do only around 20" between centers, but I have an aluminum extension
that will hold a tailstock way out there for woodwork. And, of course, both
the steady rest and the hole through the headstock let you do longer work
that's thin.

With steady rest, taper attachment, three jaw chuck, four jaw chuck,
faceplates, legs, and 1/2 hp single phase motor mounted on a separate floor
mount (motor probably came with the lathe -- it's huge), it would probably
go today for around $850.

I've just bought a 9" South Bend at auction, with a six jaw chuck, collet
closer and collets, and miscellaneous tooling for $650. It's also got a 48"
bed, but because both the headstock and the tailstock are shorter, it will
do 30" between centers. I bought it because it's a better size for Fintry
and sits on a bench. It's somewhat younger, maybe 1965 or so.

Now the only significant disadvantage I see with these guys is that they're
heavy -- that's good when using them, but bad when moving. However, even
the 13" comes apart into pieces no one of which weighs more than around 140
pounds. The heaviest piece of the 9" (the bed) is around 90 pounds. They
won't spin up quite as fast as a wood lathe, but that's not really a
problem.

Parts for South Bend and the other standard brands are easily available --
indeed the dealers say that parting out (on eBay) is always more lucrative
than selling the whole thing -- but it's sort of beside the point, as
they're so rock solid that parts are rarely needed.

So why buy a wood lathe?

--
Jim Woodward
www.mvFintry.com


..
"Glenn Ashmore" wrote in message
news:LaNsb.560$0K4.175@lakeread04...

Adam wrote:

I have well equipped woodworking workshop.
Can I use those all machines to work with UHMW as well?
Adam

Mostly you can. I have better luck with a tripple chip carbide tipped
blade made for non-ferous metals. It has less tendancy to melt the
plastic. Drilling is easy but getting any tolerance on a wood lathe
takes a Zin that I do not possess. That really requires the presision
of a metal lathe.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com