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Almost finished with the part ... OK , what this part is , it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut into
the sleeve , as the nut is tightened the dovetail locks the crankpin to the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing and
the crank plate that mates the shaft to the crankpin . NOW , the question is
how much is this sleeve going to grow when we press it on ? Do I allow for
that much growth , or less ? Once installed on the motor shaft it's going to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...

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"Terry Coombs" wrote in message ...

Almost finished with the part ... OK , what this part is , it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut into
the sleeve , as the nut is tightened the dovetail locks the crankpin to the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing and
the crank plate that mates the shaft to the crankpin . NOW , the question is
how much is this sleeve going to grow when we press it on ? Do I allow for
that much growth , or less ? Once installed on the motor shaft it's going to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...


You're probably wasting your time, and it'll throw another rod before you even get another 10 hours of run -time...**** poor design engineering.

Been there done it. Still got an old tank to prove it.

--

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"Terry Coombs" wrote in message ...

Almost finished with the part ... OK , what this part is , it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut into
the sleeve , as the nut is tightened the dovetail locks the crankpin to the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing and
the crank plate that mates the shaft to the crankpin . NOW , the question is
how much is this sleeve going to grow when we press it on ? Do I allow for
that much growth , or less ? Once installed on the motor shaft it's going to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--


Oops...forgot about the sleeve...

--what happens unless it is an exceptionally thick-walled sleeve, is that for all practical purposes the sleeve OD grows by the exact same amount as your shaft interferance fit--also, you need to be careful that any press fit sleeve is not too thin, because they will easily split...incidentally, this is a phenomena you can take advantage of for instance if you have a bearing inner race next to a shoulder and you can't get anything in there to pry it away from the shoulder....just grind a flat on the race 'til you're about .020 or so away from hitting the shaft and then give it a good whack with a hammer and sharp chisel.right at the thinned area...it'll split, allowing you to easily slide it off....

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"PrecisionmachinisT" wrote in message
news:p5CdnVRc85SyKfXMnZ2dnUVZ_jKdnZ2d@scnresearch. com...

"Terry Coombs" wrote in message
...

Almost finished with the part ... OK , what this part is , it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs
to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut
into
the sleeve , as the nut is tightened the dovetail locks the crankpin to
the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing
and
the crank plate that mates the shaft to the crankpin . NOW , the question
is
how much is this sleeve going to grow when we press it on ? Do I allow for
that much growth , or less ? Once installed on the motor shaft it's going
to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...


You're probably wasting your time, and it'll throw another rod before you
even get another 10 hours of run -time...**** poor design engineering.

Been there done it. Still got an old tank to prove it.

--


My neighbor's unit and this ain't the first time . The "press fit" sleeve
the last guy made had over .015" clearance on the motor shaft . I agree the
design leaves a lot to be desired . I also have an oilless on a wheeled 20
gal tank , and when it dies it goes - but I will keep the tank for
additional storage for the shop compressor.
--
Snag

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On Apr 12, 7:07*pm, "Terry Coombs" wrote:
* Almost finished with the part ... OK , what this part is *, it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut into
the sleeve , as the nut is tightened the dovetail locks the crankpin to the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing and
the crank plate that mates the shaft to the crankpin . NOW , the question is
how much is this sleeve going to grow when we press it on ? Do I allow for
that much growth , or less ? Once installed on the motor shaft it's going to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...

My gut says it depends on the thickness of the sleeve. A thin sleeve
will stretch . A thick sleeve will not expand as much. But can you
not turn the motor on and use some abrasive to take a little off of
the sleeve diameter?


Dan

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wrote in message
...
On Apr 12, 7:07 pm, "Terry Coombs" wrote:
Almost finished with the part ... OK , what this part is , it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs
to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut
into
the sleeve , as the nut is tightened the dovetail locks the crankpin to
the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing
and
the crank plate that mates the shaft to the crankpin . NOW , the question
is
how much is this sleeve going to grow when we press it on ? Do I allow for
that much growth , or less ? Once installed on the motor shaft it's going
to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...

My gut says it depends on the thickness of the sleeve. A thin sleeve
will stretch . A thick sleeve will not expand as much. But can you
not turn the motor on and use some abrasive to take a little off of
the sleeve diameter?


Dan

Ah , would that it were that simple !! The bearing it must fit is the
front bearing of the motor ... As PM said , bad design . I'm going to shave
a thou off the outside , it's more important it have a good grip on the
motor shaft than it fit tightly in the bearing .
--
Snag

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"Terry Coombs" wrote in message
...
wrote in message
...
On Apr 12, 7:07 pm, "Terry Coombs" wrote:
Almost finished with the part ... OK , what this part is , it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs
to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut
into
the sleeve , as the nut is tightened the dovetail locks the crankpin to
the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing
and
the crank plate that mates the shaft to the crankpin . NOW , the question
is
how much is this sleeve going to grow when we press it on ? Do I allow
for
that much growth , or less ? Once installed on the motor shaft it's going
to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...

My gut says it depends on the thickness of the sleeve. A thin sleeve
will stretch . A thick sleeve will not expand as much. But can you
not turn the motor on and use some abrasive to take a little off of
the sleeve diameter?


Dan

Ah , would that it were that simple !! The bearing it must fit is the
front bearing of the motor ... As PM said , bad design . I'm going to
shave a thou off the outside , it's more important it have a good grip on
the motor shaft than it fit tightly in the bearing .
--
Snag

\

Assuming the finishes are quite good, you can pretty much assume that
anything beyond .0005" interference is going to cause growth. That's a
very respectable press fit for a small diameter (an inch or less).

Harold

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On Apr 12, 10:48*pm, "Terry Coombs" wrote:
wrote in message

...
On Apr 12, 7:07 pm, "Terry Coombs" wrote:



Almost finished with the part ... OK , what this part is , it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs
to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut
into
the sleeve , as the nut is tightened the dovetail locks the crankpin to
the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing
and
the crank plate that mates the shaft to the crankpin . NOW , the question
is
how much is this sleeve going to grow when we press it on ? Do I allow for
that much growth , or less ? Once installed on the motor shaft it's going
to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...

My gut says it depends on the thickness of the sleeve. *A thin sleeve
will stretch . *A thick sleeve will not expand as much. *But can you
not turn the motor on and use some abrasive to take a little off of
the sleeve diameter?

Dan

* Ah , would that it were that simple !! The bearing it must fit is the
front bearing of the motor ... As PM said , bad design . I'm going to shave
a thou off the outside , it's more important it have a good grip on the
motor shaft than it fit tightly in the bearing .
--
Snag

Still trying to picture the situation. Could you have two sleeves?
One sleeve that fits in the bearing of the motor and another sleeve
that is a press fit on the shaft and connects to the crankpin? Or
more simply can you make your sleeve with a little relief where the
motor shaft is located?

You probably have it all done by now. Hope it worked out well.

Dan

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wrote in message
...

Still trying to picture the situation.

http://i709.photobucket.com/albums/w...f/HPIM1336.jpg

http://www.allpartsinc.com/mmAllPart...s/ACG-8_01.jpg

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On Sun, 14 Apr 2013 01:30:11 GMT, "Harold & Susan Vordos"
wrote:


"Terry Coombs" wrote in message
...
wrote in message
...
On Apr 12, 7:07 pm, "Terry Coombs" wrote:
Almost finished with the part ... OK , what this part is , it's a sleeve
that goes on a motor that runs an oilless compressor . This sleeve needs
to
be press fit on the motor shaft as it transmits all the torque to the
crankpin . The crankpin has a taper that fits into a half-dovetail cut
into
the sleeve , as the nut is tightened the dovetail locks the crankpin to
the
sleeve/shaft .
I currently have it machined for a .0015 interference fit ~ .700" shaft
diameter. The outside has to be a hand-press fit into a roller bearing
and
the crank plate that mates the shaft to the crankpin . NOW , the question
is
how much is this sleeve going to grow when we press it on ? Do I allow
for
that much growth , or less ? Once installed on the motor shaft it's going
to
be difficult to turn it down if I get it wrong ... and right now I have
exactly the fit I want in the bearing .This would sure be easier if there
were holes for centers drilled into the shaft
--
Snag
My gut tells me to take the OD
down that thou-and-a-half ...

My gut says it depends on the thickness of the sleeve. A thin sleeve
will stretch . A thick sleeve will not expand as much. But can you
not turn the motor on and use some abrasive to take a little off of
the sleeve diameter?


Dan

Ah , would that it were that simple !! The bearing it must fit is the
front bearing of the motor ... As PM said , bad design . I'm going to
shave a thou off the outside , it's more important it have a good grip on
the motor shaft than it fit tightly in the bearing .
--
Snag

\

Assuming the finishes are quite good, you can pretty much assume that
anything beyond .0005" interference is going to cause growth. That's a
very respectable press fit for a small diameter (an inch or less).

Harold

Indeed it will

Gunner