According to William Wixon :
"DoN. Nichols" wrote in message
-snip-
Not necessarily -- but it takes some somewhat tricky wiring. I
wow, you ain't kiddin'
[ ... ]
whew. i've been working on this problem for hours and hours and hours.
i've been trying to figure out a solution on my own. i thought it would be
more satisfying if i could've figured it on myself. actually i do think i
came up with a workable solution but it would necessitate buying a new,
different design drum switch. (that is if Jim's CRAPPY schematic works).
i'm impressed with your wire routing.
Based on the 240final.jpg (which you mentioned later in the
e-mail) I think that it would work -- but you won't find a drum switch
with that switching pattern.
What you would need is a high-current multi-pole switch.
Looking at your drawing, I would say that a three pole three position
switch would do. Note that you are using nothing of switch terminal
(C).
So -- let's see:
================================================== ====================
Plug | Switch | Motor
================================================== ====================
Blu
o--------+--------(1)--+WWWWWWWW------------+
(L1)-----+----o------o | |
| o-----+--|--------(4)---WWWWWWWW+----------(3)
| | | Orn |
| | | |
+----o | | Red |
o------o-----|--|--------(2)--+WWWWWWWWW--)|--o/o- +
+----o | |
| | |
| | |
| o-----+ |
(L2)-----+----o------o |
o--------+
(N)-----------(G)------------------------(G)
All three switch elements move at the same time. Center is
STOP, All up is FORWARD, and all down is REVERSE.
"+" s either where two wires join, or bend at right angles
"-|-" is where two wires pass nearby without making contact.
================================================== ====================
I've actually used such a switch (with many more than three
positions, but locked to not rotate beyond those three) with the motor
on my old Atlas/Craftsman 6x18" lathe. At the time, I did not know
where to find real drum switches, but I could easily pick up switches
like these at hamfests. It has a bar handle, so it is not that
different from a drum switch in exterior operation, once I put it in a
metal box to keep chips from falling into all of those screw terminals.
[ ... ]
So you did -- and your drawing showed something which I forgot
to mention in the wiring, so it is good that you posted it, instead of
just assuming that you could use it as described. (It was the position
of the (Red) wire in the motor.
yeah, that purple wire going to nowhere was confusing me and making me feel
very depressed.
i swapped the red wire end for end and am hoping that will be ok,
red/black - black/red.
Essentially, swapping the red and the black wires from the motor
will change what is forward and what is reverse. One of several ways to
do it.
FWIW Normally, the drum switches are set up so FORWARD is moving
the handle to the left, and reverse is moving it to the right. It is
good to be consistent with that -- so when you use somebody eles's
machine, you get the expected behavior. And my switch on the
Altas/Craftsman was backwards, so I had to re-train myself. :-)
I've seen electricians who would make similar mistakes. It
helps that I've done electricity and electronics as a hobby since late
grade school, and worked in it since the early 1960s until a few years
before I retired. (I spent some of the last years at work as a unix
networking administrator -- another of my hobbys. :-)
thanks again for helping me. you've really put a lot of time and energy
into this problem. i'm eternally indebted to you. i've always wished my
brain could grasp and comprehend electrical stuff. every time i've tried to
solder up some sort of home made electrical device i've failed miserably, i
mean, i can do, i believe, basic electric house wiring, and i can solder,
but electronic stuff never works.
Well ... as I said -- I was playing with this kind of thing back
when I was in grade school -- so it was plenty of time for things to
sink in. :-)
And I also did a lot of playing with telephone switch gear, so
I learned relay logic, which is not that different from what we are
doing here.
As you did. I would like to see the results of a Paint drawing
of this one done from my text description too -- so I can check for
other things which I forgot to mention, like what I forgot in the 240V
option.
thanks. i made up some more diagrams in Paint last night.
And I've downloaded them.
this one is based on Jim's (CRAPPY) schematic. i went back and forth
between Jim's (CRAPPY) schematic
Are you talking about the one from a South Bend manual by any
chance?
and the drawings in the link Glenn posted
(that have major missing information). (and my own sketches from
disassembling the motor) this is the one where i need a new/different
switch. i don't know if i can locate a switch like this to buy so was
plotting to try to modify the switch i have now.
http://www.frontiernet.net/~wwixon/240final.jpg
Comments above.
Do you have an ohmmeter? It would not hurt to check whether
:-) i have an electrical checker thing. not sure if it's called an
ohmmeter.
Can it measure resistance, or just continuity?
there are connections between terminals (2) and (4) and any other
i dissassembled the motor. as you suspeced earlier, there aren't (any
connections between 2 and 4).
Good -- glad to have that confirmed.
i took apart the motor to trace the lines.
the only way i could figure out how to do it (easily) was to poke one of the
probes through the varnish coating on the windings wires. i'm worried it's
not ok to rupture that coating. i sprayed polyurethane onto the place where
i broke through the coating. hope that's ok too. as a side question, that
is something i could never understand. how/why the electric current wants
go to through the wires instead of just bridging across each other to the
"shortest route". i always thought that VERY thin varnish coating wouldn't
be enough to insulate the wires from each other. how does that work?!?!
Hmm ... that enamel on the wire is tough stuff, and is pretty
good insulation. And remember that no single winding on this motor has
more than 120V across it. And there is an additional layer of
insulation wrapped around each winding to separate them where they
cross. And that is quite sufficient.
I don't know how good the polyurethane is, but it is at least
better than not replacing the insulation at all.
I really would not have bothered cutting through the varnish.
Just measuring at the available wires should have been sufficient. Four
loose wires, and one to terminal (1) and one to terminal (4).
[ ... ]
Anyway -- with the wiring setup which I have suggested for 240V,
you only need three switched wires -- plus the ground -- which may make
it easier. And you can use the terminals for connections there, so you
won't have bundles of electrical tape insulating splices. :-)
:-) besides a safe installation i also like a neat installation. my intent
is to get some stranded 14ga. wire and bundle four wires
(black/white/red/green) inside a 3/8" BX jacket to run between the motor
and the switch (with crimp eye connectors on the ends) and run a 14/3
extension cord from the switch to the 240 wall socket.
O.K. One suggestion. Don't use white -- look for some other
color, because white should be neutral in house wiring (even though
black is ground in electronics wiring).
[ ... ]
P.S. Out of curiosity -- why do you not use capital letters for
the start of sentences and for the pronoun "I" (including forms
like "I'd" "I'll", "I'm" and such)?
sorry about that. it must be a habit picked up from using various chat
programs. typing as fast as possible. the long explanation for not using
capital "I" is i was trying to train myself to have some humility.
I was afraid that latter was the reason for the lower-case 'i'.
I opt to go with the standard English language writing process, as it is
easier for others to read. (And the capital on the first word of each
sentence helps to distinguish between a period '.' and a comma ',' --
which are a bit difficult to tell apart on my screen at my usual
distance.
[ ... ]
thanks Don dude!
You're welcome.
b.w.
oh, i uploaded a cleaned-up version of your wire routing drawing.
www.frontiernet.net/~wwixon/240dons.jpg
i swapped the wires to "C" and "D" as you suggested. and swapped black for
red.
You mean 'C' and 'B'? That was for the case of the motor
running the wrong direction when you switch it to forward. Just showing
you one of the easy ways to set things up so the motor runs the right
direction when switched to FORWARD.
The wires on (E) and (F) can be interchanged as well, but I
selected that pattern to make the (L2) hot line jumper between (F) and
(D) short, and not have to jump around the switch. There are also ways
to set it up with (A), (B), (C), and (D) to move that hot line to (C)
and (E), and the other hot to (B). But I started out with one hot to
(A), and that sort of pre-selected (D) as the other hot.
Oh yes -- another thing. The 240dons.jpg image brings another
thing to mind. I don't know how the motor and the switch are mounted to
your lathe, but at least one of them needs to be firmly grounded to the
lathe's frame -- or you need to continue the ground wire off to the
frame as well. Some motors are mounted via a rubber bushing between the
frame/base and the motor itself, so that would leave the motor floating
relative to the lathe frame. In my case, the drum switch is screwed
directly to the headstock casting, so it is well enough grounded.
Enjoy,
DoN.
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