AC switch in old Johnson Bandsaw.

[gghe...@gmail.com]

Hi all, we've got an old Johnson bandsaw

https://www.dropbox.com/s/hqi6vnwjjoqsngk/Bandsaw.JPG?dl=0

There's a lever going to a switch that cuts off power once
you hit the bottom of the piece... the switch broke yesterday.

https://www.dropbox.com/s/b9may1gvk2teptc/Switch.JPG?dl=0

It's basically just an AC wall switch with a
mechanical connection to the switch action.

What is it called? and
Where do I go to get a replacement

Thanks

George H.

[gghe...@gmail.com]

Looking here,
http://www.industrialmanuals.com/machine_manuals/pdfs/J-130%20Johnson%20Model%20B%20Metal%20Cutting%20Bandsaw%20Instruction%20Parts%20Manual.pdf

I find the switch is/was a Bryant toggle 3972SH.. but that doesn't help much.

George H.

[dpb]

On 09/21/2016 8:43 AM, gghe...@gmail.com wrote:
...

> There's a lever going to a switch that cuts off power once
> you hit the bottom of the piece... the switch broke yesterday.
>
> https://www.dropbox.com/s/b9may1gvk2teptc/Switch.JPG?dl=0
>
> It's basically just an AC wall switch with a
> mechanical connection to the switch action.
>
> What is it called? and
> Where do I go to get a replacement

I guess you mean the electrical "broke"; mechanically it still looks sound?

I've seen 'em; don't have a specific name nor distributor unfortunately,
sorry.

I think I'd start by adapting a regular switch; the actual force isn't
_that_ much is it?

I was able to find references in old aircraft national parts id
numbering databases to the Bryant switch the other posted but no links
to current inventory. Bryant Electrical search didn't find the part as
current but guess you could always contact them for substitute.

Second choice I'd make would be to take it to the local industrial
electrical supply jobber in your location and as them to come up with a
substitute.

[gghe...@gmail.com]

On Wednesday, September 21, 2016 at 1:50:20 PM UTC-4, dpb wrote:
> On 09/21/2016 8:43 AM, gghe...@gmail.com wrote:
> ...
>
> > There's a lever going to a switch that cuts off power once
> > you hit the bottom of the piece... the switch broke yesterday.
> >
> > https://www.dropbox.com/s/b9may1gvk2teptc/Switch.JPG?dl=0
> >
> > It's basically just an AC wall switch with a
> > mechanical connection to the switch action.
> >
> > What is it called? and
> > Where do I go to get a replacement
>
> I guess you mean the electrical "broke"; mechanically it still looks sound?

Well I took it apart and got it to work again for a few cycles.
But there is a broken piece of metal that should stop the
contact from moving too far... When it moves to far the
spring on the bottom falls out and.. broke.

>
> I've seen 'em; don't have a specific name nor distributor unfortunately,
> sorry.
>
> I think I'd start by adapting a regular switch; the actual force isn't
> _that_ much is it?
>
> I was able to find references in old aircraft national parts id
> numbering databases to the Bryant switch the other posted but no links
> to current inventory. Bryant Electrical search didn't find the part as
> current but guess you could always contact them for substitute.

Thanks, I think I did a similar pointless search.

>
> Second choice I'd make would be to take it to the local industrial
> electrical supply jobber in your location and as them to come up with a
> substitute.

Yeah I figure that is my next step... If they can't help I'll
have to modify some other switch.

Thanks,

George H.

[Bob La Londe]

<gghe...@gmail.com> wrote in message
news:621280df-c087-4455...@googlegroups.com...

My little bandsaw has a switch that just gets pushed down by a metal tab
when it cuts through. It works ok if I brush all the swarf off the machine
very single time before starting a job, but even then its not 100% when
cutting something big as the swarf builds up again.

I am sure you can come up with something.

[dpb]

On 09/21/2016 1:07 PM, gghe...@gmail.com wrote:
> On Wednesday, September 21, 2016 at 1:50:20 PM UTC-4, dpb wrote:

...

>> I guess you mean the electrical "broke"; mechanically it still looks sound?
>
> Well I took it apart and got it to work again for a few cycles.
> But there is a broken piece of metal that should stop the
> contact from moving too far... When it moves to far the
> spring on the bottom falls out and.. broke.

...

Hmmm....that piece couldn't be repaired?

The cheap Chinese bench grinder I keep the wire wheels on had a switch
failure, too; a spring-loaded mechanical flip-flop pulled a
copper-plated lug in place across two contacts. It relaxed/bent first
time a number of years ago and was able to straighten it out and keep
going until this summer sometime it got so weak it wouldn't hold at all.
It was easy enough to swap out a toggle switch with a cover plate for
the big hole but I kept the old 'un; maybe at some point in time I'll
try to fab a new bar for it...

For yours, looks like a regular switch with the contact rating required
would work just drill out the need hole for the link pin. Might try to
epoxy on a couple thin metal strips along the sides for a little
reinforcement but would think that'd last quite a while that way...

[amdx]

I would end up mounting a microswitch with an attached lever
and energize/deenergize a relay that drives the motor. But those are
both in my junque box.
Mikek

[DoN. Nichols]

On 2016-09-21, gghe...@gmail.com <gghe...@gmail.com> wrote:
> Hi all, we've got an old Johnson bandsaw
>
> https://www.dropbox.com/s/hqi6vnwjjoqsngk/Bandsaw.JPG?dl=0
>
> There's a lever going to a switch that cuts off power once
> you hit the bottom of the piece... the switch broke yesterday.
>
> https://www.dropbox.com/s/b9may1gvk2teptc/Switch.JPG?dl=0
>
> It's basically just an AC wall switch with a
> mechanical connection to the switch action.

A bit more than that. It appears to be switching both sides of
the line (a good thing for safety when running from 240 VAC), and it
appears to be quite old, as it has a ceramic housing instead of bakelite
or some other plastic.

> What is it called? and
> Where do I go to get a replacement

Not sure what the name is in the home construction trade, but I
would guess that it is a DPST (Double Pole Single Throw) toggle switch.)
It is not a common switch for home wiring, but rather for switching.
Note the four terminal screws. It looks like two are brass colored and
two nickel plated to indicate the two circuits.

Now -- one home switch might look like that, and I think that
electricians would call it a four-way switch. It would be used in the
middle of a set of three switches, between two three-way switches, any
one of which could turn the lights on or off. But that would not be
what you needed for the 240 VAC motor.

And the toggle looks a bit weird to -- the handle is missing,
and there are two metal plates which could accept a rivet or screw
between them to accept the linkage rod to the external operating lever.

I might replace it with a relay (enclosed, so the metal shavings
could not short it out) controlled by a lighter duty switch located
where you need to reach it.

Good Luck,
DoN.

--
Remove oil spill source from e-mail
Email: <BPdnic...@d-and-d.com> | (KV4PH) Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
--- Black Holes are where God is dividing by zero ---

[Michael A. Terrell]

How about a real limit switch? http://www.ebay.com/itm/380653721209


CUTLER-HAMMER-10316H16C-SINGLE-POLE-DOUBLE-THROW-LIMIT-SWITCH-10316H-16C-USPP-/

--
Never piss off an Engineer!

They don't get mad.

They don't get even.

They go for over unity! ;-)

[gghe...@gmail.com]

Well I went to the local electrical supply place. They looked at it
and scratched their heads... So I had them sell me a regular switch with the
same current rating.
Drilled a hole in the handle.. a little cutting, bending, and fitting to get
the right length and we are back in business.

Thanks all,
George H.

[Leon Fisk]

On Thu, 22 Sep 2016 06:34:23 -0700 (PDT)
gghe...@gmail.com wrote:

<snip>

>Well I went to the local electrical supply place. They looked at it
>and scratched their heads... So I had them sell me a regular switch with the
>same current rating.
>Drilled a hole in the handle.. a little cutting, bending, and fitting to get
>the right length and we are back in business.

You might be able to adapt one of these covers and use the same style
switch you just purchased if your modification gives out:

https://www.grainger.com/product/BELL-Die-Cast-Zinc-Weatherproof-WP34297/

Kind of depends on what the switch handle is made of and how much
pressure your mod puts on it as to how well it will hold up. dpw's idea
of reinforcing the handle with some metal is good too...

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

[Larry Jaques]

He needs a DPST, not an SPDT. I'm with Don on the AC relay as a
simple fix, with a simple wall switch actuator.

--
The goal to strive for is a poor government but a rich people.

--Andrew Johnson

[Michael A. Terrell]

Larry Jaques wrote:

>
> Michael A. Terrell wrote:
>>
>> How about a real limit switch? http://www.ebay.com/itm/380653721209
>>
>>
>> CUTLER-HAMMER-10316H16C-SINGLE-POLE-DOUBLE-THROW-LIMIT-SWITCH-10316H-16C-USPP-/
>
> He needs a DPST, not an SPDT. I'm with Don on the AC relay as a
> simple fix, with a simple wall switch actuator.

The photo in the listing shows four terminals in two sets of two, so
it looks like the description is wrong.

[DoN. Nichols]

On 2016-09-22, Michael A. Terrell <mike.t...@earthlink.net> wrote:
> Larry Jaques wrote:
>>
>> Michael A. Terrell wrote:
>>>
>>> How about a real limit switch? http://www.ebay.com/itm/380653721209
>>>
>>>
>>> CUTLER-HAMMER-10316H16C-SINGLE-POLE-DOUBLE-THROW-LIMIT-SWITCH-10316H-16C-USPP-/
>>
>> He needs a DPST, not an SPDT. I'm with Don on the AC relay as a
>> simple fix, with a simple wall switch actuator.
>
>
> The photo in the listing shows four terminals in two sets of two, so
> it looks like the description is wrong.

The photo of the label shows that it has either one pair of
terminals connected or a second one. Sort of single pole single throw,
if you connect say screws 2 and 3 together.

Not what is needed in this case -- assuming a 240 VAC motor.

Enjoy,

[Michael A. Terrell]

DoN. Nichols wrote:
> On 2016-09-22, Michael A. Terrell <mike.t...@earthlink.net> wrote:
>> Larry Jaques wrote:
>>>
>>> Michael A. Terrell wrote:
>>>>
>>>> How about a real limit switch? http://www.ebay.com/itm/380653721209
>>>>
>>>>
>>>> CUTLER-HAMMER-10316H16C-SINGLE-POLE-DOUBLE-THROW-LIMIT-SWITCH-10316H-16C-USPP-/
>>>
>>> He needs a DPST, not an SPDT. I'm with Don on the AC relay as a
>>> simple fix, with a simple wall switch actuator.
>>
>>
>> The photo in the listing shows four terminals in two sets of two, so
>> it looks like the description is wrong.
>
>
> The photo of the label shows that it has either one pair of
> terminals connected or a second one. Sort of single pole single throw,
> if you connect say screws 2 and 3 together.
>
> Not what is needed in this case -- assuming a 240 VAC motor.

I would use a small two pole contactor to shut off the motor. It
would be able to handle a lot more current, and reduce the wear on the
actual limit switch.

[gghe...@gmail.com]

On Friday, September 23, 2016 at 12:22:55 AM UTC-4, DoN. Nichols wrote:
> On 2016-09-22, Michael A. Terrell <mike.t...@earthlink.net> wrote:
> > Larry Jaques wrote:
> >>
> >> Michael A. Terrell wrote:
> >>>
> >>> How about a real limit switch? http://www.ebay.com/itm/380653721209
> >>>
> >>>
> >>> CUTLER-HAMMER-10316H16C-SINGLE-POLE-DOUBLE-THROW-LIMIT-SWITCH-10316H-16C-USPP-/
> >>
> >> He needs a DPST, not an SPDT. I'm with Don on the AC relay as a
> >> simple fix, with a simple wall switch actuator.
> >
> >
> > The photo in the listing shows four terminals in two sets of two, so
> > it looks like the description is wrong.
>
>
> The photo of the label shows that it has either one pair of
> terminals connected or a second one. Sort of single pole single throw,
> if you connect say screws 2 and 3 together.
>
> Not what is needed in this case -- assuming a 240 VAC motor.
>
> Enjoy,
> DoN.

Hi all, not that it matters, but the motor was 120 VAC and I just needed
a single pole switch. Only 1/2 of the switch shown in the picture was
used.

George H.

[Jim Wilkins]

<gghe...@gmail.com> wrote in message
news:e931fc87-ce5e-49f9...@googlegroups.com...

What matters is if you can solve a wiring problem with commercial
household hardware or need to hunt down the industrial stuff.

https://en.wikipedia.org/wiki/Multiway_switching
Commercial wall switches called "four-way" aren't true DPDT because
they are internally cross-connected to act as reversing switches.

If wired correctly, the relay circuit others have suggested has the
safety advantage that if the power goes out while the machine is
running, it won't restart when the power returns and you are
elsewhere.

--jsw

[Gunner Asch]

On Fri, 23 Sep 2016 05:35:05 -0700 (PDT), gghe...@gmail.com wrote:

>On Friday, September 23, 2016 at 12:22:55 AM UTC-4, DoN. Nichols wrote:
>> On 2016-09-22, Michael A. Terrell <mike.t...@earthlink.net> wrote:
>> > Larry Jaques wrote:
>> >>
>> >> Michael A. Terrell wrote:
>> >>>
>> >>> How about a real limit switch? http://www.ebay.com/itm/380653721209
>> >>>
>> >>>
>> >>> CUTLER-HAMMER-10316H16C-SINGLE-POLE-DOUBLE-THROW-LIMIT-SWITCH-10316H-16C-USPP-/
>> >>
>> >> He needs a DPST, not an SPDT. I'm with Don on the AC relay as a
>> >> simple fix, with a simple wall switch actuator.
>> >
>> >
>> > The photo in the listing shows four terminals in two sets of two, so
>> > it looks like the description is wrong.
>>
>>
>> The photo of the label shows that it has either one pair of
>> terminals connected or a second one. Sort of single pole single throw,
>> if you connect say screws 2 and 3 together.
>>
>> Not what is needed in this case -- assuming a 240 VAC motor.
>>
>> Enjoy,
>> DoN.
>
>Hi all, not that it matters, but the motor was 120 VAC and I just needed
>a single pole switch. Only 1/2 of the switch shown in the picture was
>used.
>
>George H.

The reason a 2 pole switch is used in this type of machine is
simple...you want to be able to turn off BOTH legs of power when the
cut is done or the machine is turned off.

On a 110vt circuit...it works the same..removes both the hot and the
neutral. "Best Practices".
What happens if Joe Nose Picker cut the cord/plug off your saw by
accident and then reinstalls it...but reverses the black and white
wires? Saw will run properly..but when the single pole switch is
opened..it opens the Neutral..leaving the hot wire still alive. That
can be something of a nasty surprise.

Many industrial single phase machines can be changed from 110 to 220,
simply by changing the wireing. Dual windings..shrug..or at worst
simply swapping in a different motor. Same if running it on a
transformer....etc etc. That single pole switch ..under your control
in your home shop is just fine..but in Industry..safety people often
go the distance and make sure the device is Safe.

>>
>> --
>> Remove oil spill source from e-mail
>> Email: <BPdnic...@d-and-d.com> | (KV4PH) Voice (all times): (703) 938-4564
>> (too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
>> --- Black Holes are where God is dividing by zero ---

---
This email has been checked for viruses by Avast antivirus software.
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[Jim Wilkins]

"Gunner Asch" <gunne...@gmail.com> wrote in message
news:1hgaubt25s5n8jfav...@4ax.com...

I once had the side job of ensuring that the wiring of exported custom
machinery met the national and company standards. We normally switched
all incoming power wires but I vaguely remember one case (Mitel?)
where we had to leave the Neutral permanently connected, perhaps for
Ontario Hydro's specs.

The difference was in the assumptions of most likely fault conditions.
IIRC for that one the wiring would always be correct but the switch
contacts could burn open or weld shut.

I've certainly seen commercial wall switches and GFI outlets fail.
Last month.I replaced a 10-year-old lighted switch that failed open.
--jsw

[Jim Wilkins]

"Jim Wilkins" <murat...@gmail.com> wrote in message
news:ns3n1l$q16$1...@dont-email.me...

http://www.ecmag.com/section/codes-standards/switching-neutral-ok

[gghe...@gmail.com]

Gunner and Jim W. I do appreciate your concern.
(I should tell you about the Arc welder I plugged in w/o checking the
power connections.)
Anyway I totally understand what you mean.
The deal here is that it's all wired up. To redo it the right way
would mean ripping it all apart, (and buying another dpdt wall switch.)
installing new wires, etc. Ugh.

I'm just going to live dangerously for a bit longer.
(Or get a Darwin.. :^)

George H.

[Larry Jaques]

On Fri, 23 Sep 2016 05:35:05 -0700 (PDT), gghe...@gmail.com wrote:

>On Friday, September 23, 2016 at 12:22:55 AM UTC-4, DoN. Nichols wrote:
>> On 2016-09-22, Michael A. Terrell <mike.t...@earthlink.net> wrote:
>> > Larry Jaques wrote:
>> >>
>> >> Michael A. Terrell wrote:
>> >>>
>> >>> How about a real limit switch? http://www.ebay.com/itm/380653721209
>> >>>
>> >>>
>> >>> CUTLER-HAMMER-10316H16C-SINGLE-POLE-DOUBLE-THROW-LIMIT-SWITCH-10316H-16C-USPP-/
>> >>
>> >> He needs a DPST, not an SPDT. I'm with Don on the AC relay as a
>> >> simple fix, with a simple wall switch actuator.
>> >
>> >
>> > The photo in the listing shows four terminals in two sets of two, so
>> > it looks like the description is wrong.
>>
>>
>> The photo of the label shows that it has either one pair of
>> terminals connected or a second one. Sort of single pole single throw,
>> if you connect say screws 2 and 3 together.
>>
>> Not what is needed in this case -- assuming a 240 VAC motor.
>>
>> Enjoy,
>> DoN.
>
>Hi all, not that it matters, but the motor was 120 VAC and I just needed
>a single pole switch. Only 1/2 of the switch shown in the picture was
>used.

So why dincha just move the leads to the other set of contacts and be
done with it? <g>

[Gunner Asch]

Just tell us you got the hot side on the switch, and not the
neutral...ok?

(Grin)

[dpb]

On 09/23/2016 3:57 PM, Larry Jaques wrote:
...

> So why dincha just move the leads to the other set of contacts and be
> done with it?<g>

...

The internal mechanicals of the switch failed--I already asked that way
long ago... :)

[Larry Jaques]

On Fri, 23 Sep 2016 13:59:35 -0700, Gunner Asch <gunne...@gmail.com>
wrote:

>On Fri, 23 Sep 2016 12:59:22 -0700 (PDT), gghe...@gmail.com wrote:
>
>>On Friday, September 23, 2016 at 1:15:02 PM UTC-4, Jim Wilkins wrote:
>>> "Jim Wilkins" <murat...@gmail.com> wrote in message
>>> news:ns3n1l$q16$1...@dont-email.me...
>>>
>>> http://www.ecmag.com/section/codes-standards/switching-neutral-ok
>>
>>Gunner and Jim W. I do appreciate your concern.
>>(I should tell you about the Arc welder I plugged in w/o checking the
>>power connections.)
>>Anyway I totally understand what you mean.
>>The deal here is that it's all wired up. To redo it the right way
>>would mean ripping it all apart, (and buying another dpdt wall switch.)
>>installing new wires, etc. Ugh.
>>
>>I'm just going to live dangerously for a bit longer.
>>(Or get a Darwin.. :^)
>>
>>George H.
>
>Just tell us you got the hot side on the switch, and not the
>neutral...ok?
>
>(Grin)

Not if he's aiming for the Darwin Award.

[Jim Wilkins]

<gghe...@gmail.com> wrote in message
news:d6a1e8a6-88cb-4898...@googlegroups.com...

I'm just careful about what I suggest in a public forum.