Speed up/slow down every time you power on/off?

[BuckeyeDennis]

I'm in the habit of cranking the speed dial to slow before turning off. But I forgot to do so a couple weeks ago, and I had it all the way up to high speed. When it came time to power back up, I had only a drill chuck mounted and was running on a 20A service. So I decided to try just switching it on.

Well, the SS was actually plugged in to a 15A Belkin spike-limiting power strip that I have mounted to my workbench. The start-up surge from the SS at high speed immediately killed the power strip -- I found that it had vaporized a section of wide PCB track.

The power strip was easy to repair. I just soldered some 16AWG wire across the blown track, and all was well again. But that kind of current surge has to be tough on the SS switch contacts.

[dusty]

I'm in the habit of cranking the speed dial to slow before turning off. But I forgot to do so a couple weeks ago, and I had it all the way up to high speed. When it came time to power back up, I had only a drill chuck mounted and was running on a 20A service. So I decided to try just switching it on.

Well, the SS was actually plugged in to a 15A Belkin spike-limiting power strip that I have mounted to my workbench. The start-up surge from the SS at high speed immediately killed the power strip -- I found that it had vaporized a section of wide PCB track.

The power strip was easy to repair. I just soldered some 16AWG wire across the blown track, and all was well again. But that kind of current surge has to be tough on the SS switch contacts.

I am not at all surprised that you fried the Belkin Power Strip. Check the current rating on that power strip. I'd bet it to be less than 15amp.

[BuckeyeDennis]

I am not at all surprised that you fried the Belkin Power Strip. Check the current rating on that power strip. I'd bet it to be less than 15amp.

I just double-checked. It's rated at 15A, 125V, 1875W. But there is no surge-current rating given, and it apparently behaves like a fast-acting fuse. A motor circuit needs a time-delay (a.k.a. slow-blow) fuse.

[reible]

I think most of us have our own rules as to how we deal with the power down/on/off issue.

My original machine from 1976 has never had the power switch replaced nor does it trip breakers. I can't speak to previous owners of the other machines I own but they all seem to handle being powered up and down no matter what the speed setting.

So my rules are to leave it at speed for the operations I'm doing, ie sawing up a bunch of pieces, same goes for sanding/drilling etc. When I change from say saw mode to a disk sanding I crank the speed down to disk sanding speed before I change the set up. In most cases I don't go all the way to slow.

At the end of a project or the end of the day I do like to go all the way down to slow. I can't say that always happens, like the shopsmith I have set up as a drill press I leave at where it is set. Since it is vertical there is little danger that I will be attaching anything to it but the drill chuck or the speed reducer....

The other thing I do is try not to operate the machine when the temperature is below 50 degrees. I once used some ill advice and put bee's wax on the speed controller, at 50 degrees I ended up have to chip it off in order to change speeds. It did power up but until I got the wax off it would not change speeds. Not so sure how much lower a temperature I'd work in anyway but for me that is my limit.

I also have a rule that if I'm not 100% concentrating on woodworking I don't use power tools. To easy to forget to make all the safety checks (which includes tool speeds) etc if you are only half into it.

Summery might be that the shopsmith can in most cases handle the task, the other part is more about you doing your part to be safe and not damaging things.

Ed

[billmayo]

AMEN!! Very true statements that I follow.

[BuckeyeDennis]

I think most of us have our own rules as to how we deal with the power down/on/off issue.

My original machine from 1976 has never had the power switch replaced nor does it trip breakers. I can't speak to previous owners of the other machines I own but they all seem to handle being powered up and down no matter what the speed setting.

So my rules are to leave it at speed for the operations I'm doing, ie sawing up a bunch of pieces, same goes for sanding/drilling etc. When I change from say saw mode to a disk sanding I crank the speed down to disk sanding speed before I change the set up. In most cases I don't go all the way to slow.

At the end of a project or the end of the day I do like to go all the way down to slow. I can't say that always happens, like the shopsmith I have set up as a drill press I leave at where it is set. Since it is vertical there is little danger that I will be attaching anything to it but the drill chuck or the speed reducer....

The other thing I do is try not to operate the machine when the temperature is below 50 degrees. I once used some ill advice and put bee's wax on the speed controller, at 50 degrees I ended up have to chip it off in order to change speeds. It did power up but until I got the wax off it would not change speeds. Not so sure how much lower a temperature I'd work in anyway but for me that is my limit.

I also have a rule that if I'm not 100% concentrating on woodworking I don't use power tools. To easy to forget to make all the safety checks (which includes tool speeds) etc if you are only half into it.

Summery might be that the shopsmith can in most cases handle the task, the other part is more about you doing your part to be safe and not damaging things.

Ed

Your approach would sure save considerable time and hassle, compared to what I've been doing. And I can't argue with the results. I'll plug mine directly into a 20A outlet and give it a try.

[apexsunguitars]

I also have a rule that if I'm not 100% concentrating on woodworking I don't use power tools. To easy to forget to make all the safety checks (which includes tool speeds) etc if you are only half into it.

amen to that!

[JPG]

I would not attempt to connect an induction motor to a typical 'power strip' since the common practice of using printed circuitry when line surge protection(and worse all connectons to sockets) is present does indeed act as a fuse. The SS motor surge is above 25A and even higher if starting under load. The printed circuit foil can take overload current but only for a very short duration. Also the use of solder makes for a problem if overheating occurs.

As for the switch making, the start up current is delayed due to the inductive load presented by the motor coils. That same inductance causes potential arcing when the switch is opened. That arcing is what wears switches out. IIUC the hp rating of a switch is directly related to contact size. Switches can arc when making, but that is caused by contact 'bounce'(brief period of make/break/make/break/. . .sequence) and would occur while the current to a motor is still ramping up.

The typical 'power strip' came about with the advent of personal computers and serves that function reasonably well. There are great differences in their construction. The less 'robust' designs will perform poorly under with higher current 'appliances'.

[dusty]

I would not attempt to connect an induction motor to a typical 'power strip' since the common practice of using printed circuitry when line surge protection(and worse all connectons to sockets) is present does indeed act as a fuse. The SS motor surge is above 25A and even higher if starting under load. The printed circuit foil can take overload current but only for a very short duration. Also the use of solder makes for a problem if overheating occurs.

As for the switch making, the start up current is delayed due to the inductive load presented by the motor coils. That same inductance causes potential arcing when the switch is opened. That arcing is what wears switches out. IIUC the hp rating of a switch is directly related to contact size. Switches can arc when making, but that is caused by contact 'bounce'(brief period of make/break/make/break/. . .sequence) and would occur while the current to a motor is still ramping up.

The typical 'power strip' came about with the advent of personal computers and serves that function reasonably well. There are great differences in their construction. The less 'robust' designs will perform poorly under with higher current 'appliances'.

The start up current for a 510 is higher than the run current but it is very short duration and should have no ill effect given that the supplied power (115 vac) is adequate and applied through proper wiring (12 or 14 gauge wire with either a 15 or 20 amp breaker).

I have posted a uTube video showing the currents being drawn during startup.

[fredsheldon]

Now if you had a Pow, oh never mind.