My new-old stock gast rotart vane pump just died. I though it broke a
shear pin as only the motor was still spinning. I know, it makes no sense
to have a have shear pin in a small tabletop style pressure/vacuum pump.

Apparently the rotor was held to the motor shaft with some sort of
loctite, at least according to the manual and it broke free. The shaft is
round and nearly polished, same for the bore of the rotor. The service
manual says sent it to a repair depot and never mess with the rotor.
Forget that.

What's the best loctite to attach the 1/2" shaft to the about 2.5"
diameter rotor? They will be wet at all times with light motor oil, and
the runnning temp is too hot to touch for more than a few seconds. I've
not used loctite under those conditions.

The stuff that broke free looks slightly yellow, like 5 minute epoxy of
some type.

It just seems like real cheap, ****ty design to me. I've never seen the
inside of pump held together with glue.

On Sat, 25 Mar 2017 20:52:23 +0000 (UTC), Cydrome Leader
wrote:

My new-old stock gast rotart vane pump just died. I though it broke a
shear pin as only the motor was still spinning. I know, it makes no sense
to have a have shear pin in a small tabletop style pressure/vacuum pump.

Apparently the rotor was held to the motor shaft with some sort of
loctite, at least according to the manual and it broke free. The shaft is
round and nearly polished, same for the bore of the rotor. The service
manual says sent it to a repair depot and never mess with the rotor.
Forget that.

What's the best loctite to attach the 1/2" shaft to the about 2.5"
diameter rotor? They will be wet at all times with light motor oil, and
the runnning temp is too hot to touch for more than a few seconds. I've
not used loctite under those conditions.

The stuff that broke free looks slightly yellow, like 5 minute epoxy of
some type.

It just seems like real cheap, ****ty design to me. I've never seen the
inside of pump held together with glue.


Drill it, loctite it and then push in a roll pin.

Gunner Asch wrote:
On Sat, 25 Mar 2017 20:52:23 +0000 (UTC), Cydrome Leader
wrote:

My new-old stock gast rotart vane pump just died. I though it broke a
shear pin as only the motor was still spinning. I know, it makes no sense
to have a have shear pin in a small tabletop style pressure/vacuum pump.

Apparently the rotor was held to the motor shaft with some sort of
loctite, at least according to the manual and it broke free. The shaft is
round and nearly polished, same for the bore of the rotor. The service
manual says sent it to a repair depot and never mess with the rotor.
Forget that.

What's the best loctite to attach the 1/2" shaft to the about 2.5"
diameter rotor? They will be wet at all times with light motor oil, and
the runnning temp is too hot to touch for more than a few seconds. I've
not used loctite under those conditions.

The stuff that broke free looks slightly yellow, like 5 minute epoxy of
some type.

It just seems like real cheap, ****ty design to me. I've never seen the
inside of pump held together with glue.


Drill it, loctite it and then push in a roll pin.

Of course after hitting post I did locate some henckel 243 which is
alleged to be the oil resistant blue stuff. I don't have any super thin
skinny aircraft type bits to get in there unless the end bell of the motor
comes off. This is a single casting that acts as the side of of the pump
and holds the motor together. Not sure of they added some obnoxious seals
in there so we'll just see if the blue stuff works.

Still baffled by the rotor glued to a shaft design. It's not even an
interference fit.

What's the name for installing a roll pin in the direction of a shaft,
sort of like how a square key sits? That might be the lazy next option.

"Cydrome Leader" wrote in message
news
Gunner Asch wrote:
On Sat, 25 Mar 2017 20:52:23 +0000 (UTC), Cydrome Leader
wrote:

My new-old stock gast rotart vane pump just died. I though it broke
a
shear pin as only the motor was still spinning. I know, it makes no
sense
to have a have shear pin in a small tabletop style pressure/vacuum
pump.

Apparently the rotor was held to the motor shaft with some sort of
loctite, at least according to the manual and it broke free. The
shaft is
round and nearly polished, same for the bore of the rotor. The
service
manual says sent it to a repair depot and never mess with the
rotor.
Forget that.

What's the best loctite to attach the 1/2" shaft to the about 2.5"
diameter rotor? They will be wet at all times with light motor oil,
and
the runnning temp is too hot to touch for more than a few seconds.
I've
not used loctite under those conditions.

The stuff that broke free looks slightly yellow, like 5 minute
epoxy of
some type.

It just seems like real cheap, ****ty design to me. I've never seen
the
inside of pump held together with glue.


Drill it, loctite it and then push in a roll pin.

Of course after hitting post I did locate some henckel 243 which is
alleged to be the oil resistant blue stuff. I don't have any super
thin
skinny aircraft type bits to get in there unless the end bell of the
motor
comes off. This is a single casting that acts as the side of of the
pump
and holds the motor together. Not sure of they added some obnoxious
seals
in there so we'll just see if the blue stuff works.

Still baffled by the rotor glued to a shaft design. It's not even an
interference fit.

What's the name for installing a roll pin in the direction of a
shaft,
sort of like how a square key sits? That might be the lazy next
option.

Dutchman or Scotch key.
http://www.practicalmachinist.com/vb...62/index2.html

Good luck drilling straight along the seam between different
materials.

-jsw

On Saturday, March 25, 2017 at 4:52:27 PM UTC-4, Cydrome Leader wrote:
My new-old stock gast rotart vane pump just died. I though it broke a
shear pin as only the motor was still spinning. I know, it makes no sense
to have a have shear pin in a small tabletop style pressure/vacuum pump.


Where do you live? At times the scrap yard gets some medical hardware. Like pumps from oxygen concentrators. They get two sizes of pumps.

Dan

On Sun, 26 Mar 2017 18:29:54 -0400, "Jim Wilkins"
wrote:


"Cydrome Leader" wrote in message
news


What's the name for installing a roll pin in the direction of a
shaft,
sort of like how a square key sits? That might be the lazy next
option.

Dutchman or Scotch key.
http://www.practicalmachinist.com/vb...62/index2.html

Good luck drilling straight along the seam between different
materials.

-jsw


Around here a Dutchman is an inlaid patch, most often a repair to a
defect in a wooden piece. I know the device under discussion as a
Dutch pin.

The problem drilling the joint between different materials can be
minimized by starting the hole with an end mill as close as possible
to the desired size, then enlarging, if necessary, with a drill. Still
can be pucker-inducing.

My preference is for a tapped hole and set screw instead of a pin.
Easier to disassemble, less fussy than fitting a pin, and also retains
the mounted component in the axial direction.

--
Ned Simmons

On Sun, 26 Mar 2017 21:30:58 -0400, Ned Simmons
wrote:

On Sun, 26 Mar 2017 18:29:54 -0400, "Jim Wilkins"
wrote:


"Cydrome Leader" wrote in message
news


What's the name for installing a roll pin in the direction of a
shaft,
sort of like how a square key sits? That might be the lazy next
option.

Dutchman or Scotch key.
http://www.practicalmachinist.com/vb...62/index2.html

Good luck drilling straight along the seam between different
materials.

-jsw


Around here a Dutchman is an inlaid patch, most often a repair to a
defect in a wooden piece. I know the device under discussion as a
Dutch pin.

The problem drilling the joint between different materials can be
minimized by starting the hole with an end mill as close as possible
to the desired size, then enlarging, if necessary, with a drill. Still
can be pucker-inducing.

My preference is for a tapped hole and set screw instead of a pin.
Easier to disassemble, less fussy than fitting a pin, and also retains
the mounted component in the axial direction.

True indeed. Assuming that there is enough material to hold said
setscrew. Most of the vac impeller/shafts Ive seen used minimal
materials. But if he has enough material to hold a set screw..by all
means..use it. A pointed one would be best. Shrug

Gunner

On Saturday, March 25, 2017 at 4:52:27 PM UTC-4, Cydrome Leader wrote:
My new-old stock gast rotart vane pump just died. I though it broke a
shear pin as only the motor was still spinning. I know, it makes no sense
to have a have shear pin in a small tabletop style pressure/vacuum pump.

Apparently the rotor was held to the motor shaft with some sort of
loctite, at least according to the manual and it broke free. The shaft is
round and nearly polished, same for the bore of the rotor. The service
manual says sent it to a repair depot and never mess with the rotor.
Forget that.

What's the best loctite to attach the 1/2" shaft to the about 2.5"
diameter rotor? They will be wet at all times with light motor oil, and
the runnning temp is too hot to touch for more than a few seconds. I've
not used loctite under those conditions.

The stuff that broke free looks slightly yellow, like 5 minute epoxy of
some type.

It just seems like real cheap, ****ty design to me. I've never seen the
inside of pump held together with glue.

Leery of posting any metalworking advice since I know so little about it, but couldn't the motor armature be put in a lathe and the shaft knurled? Then press on the pump impeller?

"Ned Simmons" wrote in message
...
On Sun, 26 Mar 2017 18:29:54 -0400, "Jim Wilkins"
wrote:


"Cydrome Leader" wrote in message
news


What's the name for installing a roll pin in the direction of a
shaft,
sort of like how a square key sits? That might be the lazy next
option.

Dutchman or Scotch key.
http://www.practicalmachinist.com/vb...62/index2.html

Good luck drilling straight along the seam between different
materials.

-jsw


Around here a Dutchman is an inlaid patch, most often a repair to a
defect in a wooden piece. I know the device under discussion as a
Dutch pin.

The problem drilling the joint between different materials can be
minimized by starting the hole with an end mill as close as possible
to the desired size, then enlarging, if necessary, with a drill.
Still
can be pucker-inducing.

My preference is for a tapped hole and set screw instead of a pin.
Easier to disassemble, less fussy than fitting a pin, and also
retains
the mounted component in the axial direction.

--
Ned Simmons

I second that for a steel hub on a steel shaft. Otherwise tapping
along the joint bertween dissimilar materials is worse than drilling.

If the hub is softer than the shaft I broach a keyway in it. The
necessary guide is easy to turn to whatever size the hub bore may be.
You can set the broach cutting depth to not weaken the hub too much,
and adjust the cutting depth with shims sheared from hobby store brass
or tin cans.

I mill a key slot in the shaft and then make a key that's a snug fit
in the shaft and perhaps a looser one in the hub if there's space for
a setscrew. The width of the key is easier to adjust than the slots'
because you can use a larger, stiffer endmill.

The key can be stepped without much trouble if the slots are different
widths, for example if a 1/8" shaft slot needs extra cleanup passes.

-jsw

On Mon, 27 Mar 2017 09:00:22 -0400, "Jim Wilkins"
wrote:

"Ned Simmons" wrote in message
.. .
On Sun, 26 Mar 2017 18:29:54 -0400, "Jim Wilkins"
wrote:


"Cydrome Leader" wrote in message
news


What's the name for installing a roll pin in the direction of a
shaft,
sort of like how a square key sits? That might be the lazy next
option.

Dutchman or Scotch key.
http://www.practicalmachinist.com/vb...62/index2.html

Good luck drilling straight along the seam between different
materials.

-jsw


Around here a Dutchman is an inlaid patch, most often a repair to a
defect in a wooden piece. I know the device under discussion as a
Dutch pin.

The problem drilling the joint between different materials can be
minimized by starting the hole with an end mill as close as possible
to the desired size, then enlarging, if necessary, with a drill.
Still
can be pucker-inducing.

My preference is for a tapped hole and set screw instead of a pin.
Easier to disassemble, less fussy than fitting a pin, and also
retains
the mounted component in the axial direction.

--
Ned Simmons

I second that for a steel hub on a steel shaft. Otherwise tapping
along the joint bertween dissimilar materials is worse than drilling.

If the hub is softer than the shaft I broach a keyway in it. The
necessary guide is easy to turn to whatever size the hub bore may be.
You can set the broach cutting depth to not weaken the hub too much,
and adjust the cutting depth with shims sheared from hobby store brass
or tin cans.

I mill a key slot in the shaft and then make a key that's a snug fit
in the shaft and perhaps a looser one in the hub if there's space for
a setscrew. The width of the key is easier to adjust than the slots'
because you can use a larger, stiffer endmill.

The key can be stepped without much trouble if the slots are different
widths, for example if a 1/8" shaft slot needs extra cleanup passes.

-jsw


Though not as easy to remove, a broken tap is as secure as a setscrew.
g

Last time I remember doing this was mounting a herringbone sprocket
http://www.silentsync.com/silentsync...ync®-sprockets
bored out to just below the teeth (~8" ID?) on a large hollow machine
tool spindle. The sprocket was free machining steel, the spindle was
pre-hard 4140. Nerve wracking, but there's a couple set screws in the
assembly, no broken taps.

--
Ned Simmons

On Sun, 26 Mar 2017 20:26:14 -0700, Gunner Asch
wrote:

On Sun, 26 Mar 2017 21:30:58 -0400, Ned Simmons
wrote:

On Sun, 26 Mar 2017 18:29:54 -0400, "Jim Wilkins"
wrote:


"Cydrome Leader" wrote in message
news


What's the name for installing a roll pin in the direction of a
shaft,
sort of like how a square key sits? That might be the lazy next
option.

Dutchman or Scotch key.
http://www.practicalmachinist.com/vb...62/index2.html

Good luck drilling straight along the seam between different
materials.

-jsw


Around here a Dutchman is an inlaid patch, most often a repair to a
defect in a wooden piece. I know the device under discussion as a
Dutch pin.

The problem drilling the joint between different materials can be
minimized by starting the hole with an end mill as close as possible
to the desired size, then enlarging, if necessary, with a drill. Still
can be pucker-inducing.

My preference is for a tapped hole and set screw instead of a pin.
Easier to disassemble, less fussy than fitting a pin, and also retains
the mounted component in the axial direction.

True indeed. Assuming that there is enough material to hold said
setscrew. Most of the vac impeller/shafts Ive seen used minimal
materials. But if he has enough material to hold a set screw..by all
means..use it. A pointed one would be best. Shrug

Yes, whose pointed tip seats in the small conical depression in the
shaft cut by the drill bit. I drill in place, ensuring that it is
lined up. Then I remove the sleeve or gear, and tap it and run a file
or stone across the tapped hole to debur. A drop of Loctite helps it
stay there for a long time.

--
The more you know, the less you need.
-- Aboriginal Saying

"Ned Simmons" wrote in message
...
On Mon, 27 Mar 2017 09:00:22 -0400, "Jim Wilkins"
wrote:

"Ned Simmons" wrote in message
. ..
On Sun, 26 Mar 2017 18:29:54 -0400, "Jim Wilkins"
wrote:


"Cydrome Leader" wrote in message
news

What's the name for installing a roll pin in the direction of a
shaft,
sort of like how a square key sits? That might be the lazy next
option.

Dutchman or Scotch key.
http://www.practicalmachinist.com/vb...62/index2.html

Good luck drilling straight along the seam between different
materials.

-jsw


Around here a Dutchman is an inlaid patch, most often a repair to
a
defect in a wooden piece. I know the device under discussion as a
Dutch pin.

The problem drilling the joint between different materials can be
minimized by starting the hole with an end mill as close as
possible
to the desired size, then enlarging, if necessary, with a drill.
Still
can be pucker-inducing.

My preference is for a tapped hole and set screw instead of a pin.
Easier to disassemble, less fussy than fitting a pin, and also
retains
the mounted component in the axial direction.

--
Ned Simmons

I second that for a steel hub on a steel shaft. Otherwise tapping
along the joint bertween dissimilar materials is worse than
drilling.

If the hub is softer than the shaft I broach a keyway in it. The
necessary guide is easy to turn to whatever size the hub bore may
be.
You can set the broach cutting depth to not weaken the hub too much,
and adjust the cutting depth with shims sheared from hobby store
brass
or tin cans.

I mill a key slot in the shaft and then make a key that's a snug fit
in the shaft and perhaps a looser one in the hub if there's space
for
a setscrew. The width of the key is easier to adjust than the
slots'
because you can use a larger, stiffer endmill.

The key can be stepped without much trouble if the slots are
different
widths, for example if a 1/8" shaft slot needs extra cleanup passes.

-jsw


Though not as easy to remove, a broken tap is as secure as a
setscrew.
g

Last time I remember doing this was mounting a herringbone sprocket
http://www.silentsync.com/silentsync...ync®-sprockets
bored out to just below the teeth (~8" ID?) on a large hollow
machine
tool spindle. The sprocket was free machining steel, the spindle was
pre-hard 4140. Nerve wracking, but there's a couple set screws in
the
assembly, no broken taps.

--
Ned Simmons

The cast aluminum handwheel on my lathe's collet closer is attached to
the steel tube with two axial setscrews which are more in the aluminum
than in the steel. It certainly can be done by someone with more skill
than I have.
-jsw

On Mon, 27 Mar 2017 10:14:59 -0400, Ned Simmons
wrote:

On Mon, 27 Mar 2017 09:00:22 -0400, "Jim Wilkins"
wrote:

"Ned Simmons" wrote in message
. ..
On Sun, 26 Mar 2017 18:29:54 -0400, "Jim Wilkins"
wrote:


"Cydrome Leader" wrote in message
news

What's the name for installing a roll pin in the direction of a
shaft,
sort of like how a square key sits? That might be the lazy next
option.

Dutchman or Scotch key.
http://www.practicalmachinist.com/vb...62/index2.html

Good luck drilling straight along the seam between different
materials.

-jsw


Around here a Dutchman is an inlaid patch, most often a repair to a
defect in a wooden piece. I know the device under discussion as a
Dutch pin.

The problem drilling the joint between different materials can be
minimized by starting the hole with an end mill as close as possible
to the desired size, then enlarging, if necessary, with a drill.
Still
can be pucker-inducing.

My preference is for a tapped hole and set screw instead of a pin.
Easier to disassemble, less fussy than fitting a pin, and also
retains
the mounted component in the axial direction.

--
Ned Simmons

I second that for a steel hub on a steel shaft. Otherwise tapping
along the joint bertween dissimilar materials is worse than drilling.

If the hub is softer than the shaft I broach a keyway in it. The
necessary guide is easy to turn to whatever size the hub bore may be.
You can set the broach cutting depth to not weaken the hub too much,
and adjust the cutting depth with shims sheared from hobby store brass
or tin cans.

I mill a key slot in the shaft and then make a key that's a snug fit
in the shaft and perhaps a looser one in the hub if there's space for
a setscrew. The width of the key is easier to adjust than the slots'
because you can use a larger, stiffer endmill.

The key can be stepped without much trouble if the slots are different
widths, for example if a 1/8" shaft slot needs extra cleanup passes.

-jsw


Though not as easy to remove, a broken tap is as secure as a setscrew.
g

Last time I remember doing this was mounting a herringbone sprocket
http://www.silentsync.com/silentsync...ync®-sprockets
bored out to just below the teeth (~8" ID?) on a large hollow machine
tool spindle. The sprocket was free machining steel, the spindle was
pre-hard 4140. Nerve wracking, but there's a couple set screws in the
assembly, no broken taps.

I did this on my sail line reel, aluminum hub, aluminum plate flanges.
I shrank on the flanges, but not knowing the spreading force of 1000
yds. of 100 lb. monofilament, decided better safe than sorry. Worked
great.

Pete Keillor

wrote:
On Saturday, March 25, 2017 at 4:52:27 PM UTC-4, Cydrome Leader wrote:
My new-old stock gast rotart vane pump just died. I though it broke a
shear pin as only the motor was still spinning. I know, it makes no sense
to have a have shear pin in a small tabletop style pressure/vacuum pump.


Where do you live? At times the scrap yard gets some medical hardware. Like pumps from oxygen concentrators. They get two sizes of pumps.


Chicago. Pump is running again now for the time being without modifications. Did chip part of the "stone" in the output filter
that traps some of the oil vapor, so need to patch that with something.

Used medical stuff always looks too gross to deal with. The stuff is either dirty, destroyed by cleaning an sanitizers or
both.

Garrett Fulton wrote:
On Saturday, March 25, 2017 at 4:52:27 PM UTC-4, Cydrome Leader wrote:
My new-old stock gast rotart vane pump just died. I though it broke a
shear pin as only the motor was still spinning. I know, it makes no sense
to have a have shear pin in a small tabletop style pressure/vacuum pump.

Apparently the rotor was held to the motor shaft with some sort of
loctite, at least according to the manual and it broke free. The shaft is
round and nearly polished, same for the bore of the rotor. The service
manual says sent it to a repair depot and never mess with the rotor.
Forget that.

What's the best loctite to attach the 1/2" shaft to the about 2.5"
diameter rotor? They will be wet at all times with light motor oil, and
the runnning temp is too hot to touch for more than a few seconds. I've
not used loctite under those conditions.

The stuff that broke free looks slightly yellow, like 5 minute epoxy of
some type.

It just seems like real cheap, ****ty design to me. I've never seen the
inside of pump held together with glue.

Leery of posting any metalworking advice since I know so little about it, but couldn't the motor armature be put in a lathe and the shaft knurled? Then press on the pump impeller?

Yes, but then the shaft would not fit though the bearing and casting that makes up one side of the pump. They've combined that
into one bell for the motor itself to cut down on parts and price.

On Saturday, April 8, 2017 at 4:34:00 PM UTC-4, Cydrome Leader wrote:
Garrett Fulton wrote:
On Saturday, March 25, 2017 at 4:52:27 PM UTC-4, Cydrome Leader wrote:
My new-old stock gast rotart vane pump just died. I though it broke a
shear pin as only the motor was still spinning. I know, it makes no sense
to have a have shear pin in a small tabletop style pressure/vacuum pump.

Apparently the rotor was held to the motor shaft with some sort of
loctite, at least according to the manual and it broke free. The shaft is
round and nearly polished, same for the bore of the rotor. The service
manual says sent it to a repair depot and never mess with the rotor.
Forget that.

What's the best loctite to attach the 1/2" shaft to the about 2.5"
diameter rotor? They will be wet at all times with light motor oil, and
the runnning temp is too hot to touch for more than a few seconds. I've
not used loctite under those conditions.

The stuff that broke free looks slightly yellow, like 5 minute epoxy of
some type.

It just seems like real cheap, ****ty design to me. I've never seen the
inside of pump held together with glue.

Leery of posting any metalworking advice since I know so little about it, but couldn't the motor armature be put in a lathe and the shaft knurled? Then press on the pump impeller?

Yes, but then the shaft would not fit though the bearing and casting that makes up one side of the pump. They've combined that
into one bell for the motor itself to cut down on parts and price.

Understood.