mid-'50s shopsmith disassembling and cleaning -- help

mickyd · Post by **mickyd** » Sun Mar 15, 2009 9:47 am

dusty wrote:I believe that these changes are made to ALL documents that are in the
"archive of documents" for that particular "user name".

you is correct-a-mondo Dusty

dickg1 · Post by **dickg1** » Sun Mar 15, 2009 10:36 am

The only change is to your personal file. Whenever you post or reference a previous post, the program retrieves your personal data file info and presents it. Think of the process as two files - one is the text of your post, the other is your avatar, etc. Whenever you post or recall text, the avatar, etc is combined with it and there you are.

To repeatedly store the personal file info with every text or photo post would waste valuable system resources, no matter how large the server. I wouldn't doubt that in-line photos, et al. are also stored in a separate file and then combined with personal data and text upon recall.

Dick

JPG · Post by **JPG** » Sun Mar 15, 2009 10:50 am

dusty wrote:I believe that these changes are made to ALL documents that are in the
"archive of documents" for that particular "user name".

I say this because I have changed avatars and I see the oldest of my forum documents with the later avatar.

My conclusions on this phenomenon is that the messages do NOT actually contain the avatar and signature line etc, but 'have a pointer to the user'. The user info contains all that stuff. When a message is downloaded, it builds the complete message using the user file info.

P.S. took too much time between reading Dusty and this post. Dick already said the same thing.

JPG · Post by **JPG** » Sun Mar 15, 2009 11:41 am

dusty wrote:Maybe an EE could modify the diagram here to show run windings and start windings complete with capacitor and centrifugal switch and then we would understand what is going on.

For starters, we must keep the apples and the oranges in a different container.

The 'old' 3/4HP motor(with the external capacitor AND the 'start relay') is one kind of motor, and the 'later' 1 1/8HP (with the internal centrifugal switch and capacitor) is another.

They are both "2 pole" motors since they run at NEAR synchronous speed(3600RPM). These poles are physically located within the motor at 90*(1/4 around). Actually each pole has multiple windings, but that just clouds the issue. The capacitor causes the current in ONE pole to flow 1/4 cycle later in time. This creates a ROTATING MAGNETIC FIELD. This field induces a current in the armature which in turn creates its own magnetic field. These fields try to align with one another and since the pole field is 'rotating, the armature tries to rotate WITH it. A 2 pole motor cannot keep up with the rotating field and rotates at a slightly slower speed. This slower speed commonly is stated as about 3450RPM and is dependent on mechanical load. This speed difference is referred to as "SLIP".

A different method of providing the 90* phase shift is to include an inductive 'START' winding. This winding draws much more current than the 'RUN' windings and must be switched off once the motor has started to rotate. This function is provided by the centrifugal switch.

There are various varieties of 'inductive/capacitor' 'Start/run' motor out there but they all have the common trait that extra torque needs to be created to get them started. The start relay(it may switch either an extra 'start winding' or a 'start capacitor' is one method, the centrifugal switch(usually switching a 'start winding') is another.

Although this is not as simple as the 'switch on the wall', it has been simplified. I did not include the detail that the 90* shift is necessary for the motor to run after starting. This is SOMETIMES accomplished by the capacitor not being completely disconnected or another capacitor(Not too common in these sized motors). The phase shift can be created either by a capacitor OR inductively by another winding. This is why both capacitor start/run and inductive start/run versions exist.

For the narrower purpose of understanding the ShopSmith motors I believe the following can be said in good faith(I MAY not be aware of any other variety). The 3/4HP is a Capacitor start Inductive run(Not sure of this) and the 1 1/8HP is an Inductive start Capacitive run.

P.S. The winding being switched out by the start relay/switch IS the start winding.

etc92guy · Post by **etc92guy** » Sun Mar 15, 2009 1:14 pm

This is for you, Dusty -

Am I to assume in the drawing that the yellow wire is for the Run winding and the Brown wire is for the Start winding?

edward · Post by **edward** » Mon Mar 16, 2009 12:09 am

UPDATE: All put together and running except quill (bearing place gave me the wrong size). Some questions...

When I turn her on, the lights dim for a couple seconds, she lags, and then kicks in gear as the lights go back to normal. (3/4 HP -- new bearings in the motor.) If I have her turned all the way to "Fast," and flip the on switch, she trips the breaker after the lag, so I had to back her down to "Saw" (I think) in order to keep her running.

Looking at the drive shaft, she runs clockwise. Is that right?

I worry that I slightly bent the drive shaft while getting it into the headstock (I banged the &@#% out of it with my rubber mallet, even after having frozen it). Any way to check that? The reason I ask is because I was running the table saw and thought I detected a slight shifting (wobble?) in the blade on startup and slowdown.

a1gutterman · Post by **a1gutterman** » Mon Mar 16, 2009 12:14 am

edward wrote:UPDATE: All put together and running except quill (bearing place gave me the wrong size). Some questions...

When I turn her on, the lights dim for a couple seconds, she lags, and then kicks in gear as the lights go back to normal. (3/4 HP -- new bearings in the motor.) If I have her turned all the way to "Fast," and flip the on switch, she trips the breaker after the lag, so I had to back her down to "Saw" (I think) in order to keep her running.

Looking at the drive shaft, she runs clockwise. Is that right?

I worry that I slightly bent the drive shaft while getting it into the headstock (I banged the &@#% out of it with my rubber mallet, even after having frozen it). Any way to check that? The reason I ask is because I was running the table saw and thought I detected a slight shifting (wobble?) in the blade on startup and slowdown.

The thing with the lights is knot all that unusual, especially if they are on the same circuit. The tripping of the breaker at high speed turn-on is also not that unusual if you have it on an 15 amp circuit, especially with other things (those lights) working on the same circuit. If the saw blade was turning the right direction when you had it on, the motor is turning the right direction. You can use a dial indicator to measure the run out of the shaft.

edit: How did you have it in saw mode "The reason I ask is because I was running the table saw and thought I detected a slight shifting (wobble?) in the blade on startup and slowdown." with no quill???

edward · Post by **edward** » Tue Mar 17, 2009 6:52 pm

My last post was a little convoluted. I'm hoping to put quill on tonight. This thing will then be done, except accessories. This has been a long road. Thanks everyone. You people don't know how much you helped me. I'd still be cutting wood with a handsaw (not that I mind a hand saw, but straight cuts are tricky).

edward · Post by **edward** » Wed Mar 18, 2009 12:29 am

I had hoped to give you guys a good report about my completed rebuilt headstock. Alas. Rocky Mountain Supply supplied me with yet another bearing of the wrong size. This one was too big (the other was too small). I'm wondering now if I should look elsewhere. I have a Gilmer drive with a single bearing quill. Are these weird bearings?

beeg · Post by **beeg** » Wed Mar 18, 2009 12:52 am

You can do a search about the bearings here. I'm almost sure Bill Mayo posted the part number and a link as to where to get them.