High speed startups - Any negatives?

[mickyd]

Assuming your household electrical system can handle starting your ShopSmith at 'saw' speed setting or higher without tripping a breaker, should you STILL reduce to a lower speed setting prior to start up?

[beeg]

Sure you should. Just in case ya go from using the jointer, then the bandsaw. Ya might forget to reduce the speed before hooking up the BS.

[paulrussell]

Assuming your household electrical system can handle starting your ShopSmith at 'saw' speed setting or higher without tripping a breaker, should you STILL reduce to a lower speed setting prior to start up?

I've seen Nick on Sawdust Sessions turn the Shopsmith on/off/on without reducing the speed between table saw cuts.

I've always assumed the caution was so you wouldn't do something like make a table saw cut or do some high-speed lathe sanding, turn off the Shopsmith, connect a low speed tool like the bandsaw, and then start it at too high a speed.

[dusty]

If you should then I am doing wrong most of the time. I have never made it a habit to turn down the speed before I power down. If I know that I am going to change the setup, like to the bandsaw, I will turn down the speed before removing power. However, more often than not, I have to "hurry, turn the speed down".

I am now operating on a circuit that is 14 gauge with a 15 amp breaker. The receptacle is approximately 60' from the main breaker panel. The outlet is dedicated.

Remember, I hardly ever have cold weather conditions which definitely do adversely effect startup currents.

PS Oops, maybe it is a good thing I have my bandsaw on the Power Station most of the time.

[john]

Like Dusty, I usually don't power down when using the table saw and have not encountered any problems over the years. After a couple of
"near misses", with connecting the band saw, I have developed the habit of always checking and adjusting the speed before connecting the power coupler. I also check the speed when changing from saw set-up to sanding disk, etc.

Hopefully age will not affect that process and cause any more "near misses":D

Have fun, but play safe.

John

[charlese]

Well - It is pretty easy to understand when startup happens while the speed is set higher than "slow" - additional power is needed from the motor to turn the spindle(s) and whatever is or is not attached.

For my SS and many more, this increased power demand is not detectable. The only additional wear I can think of is three fold, while minor. 1st; to the plastic coupler at the end of the spindle assembly. Seems to me the plastic flutes will probably wear out a bit sooner. 2nd; to the drive belt and 3rd; to the short key and control sheave tube.

These three wear factors are off set by any wear that will be caused by ALWAYS turning back to 'slow' after each operation. This wear will occur to the speed control, pork chop, the idler shaft, short key and control sheave. Of course this wear can be minimized by maintaining a good lubrication schedule.

I used to ALWAYS return to 'slow' after each operation. This was many -many cranks. Of course, at that time, I was doing improper lubrication by not running up to high speed prior to oiling the control sheave tube. After having a breakdown of the control sheave/pork chop/speed control parts - and replacement, I changed systems.

I now leave the speed set where it was when using the tool. That does require that I ALWAYS check the speed before connecting a SPT.

Have not had any problems with this second scenario - yet!

The best system is to always make sure you have properly lubricated and cleaned the inside of the headstock. From there, the speed setting doesn't matter much, so long as SPTs are started at their proper speed range.

[JPG40504]

The original question was regarding between sawing operations. I do not, and would not anticipate any problem with doing so, with the following facts considered.

The original concerns(and reasons for recommending adjusting to slow speed before turning off) are:

1) The startup electrical demand.

2) The time taken to achieve full running speed(duration of 'startup increased current').

3) The potential of subsequent attachment of an SPT that cannot handle the higher speed(safely).

4) The possibility of moving the SS prior to next 'on cycle'.(the sheaves can open up due to vibration while moving and cause the drive belt to drop down into the pulley causing it to jam).

#1 and #2 are more significant with the 3/4 hp motor(especially #2).

I have handled #3 by short cycling on/off while turning speed dial when 'on' repetitively until proper speed setting is obtained.

Although I have never experienced #4, It was pointed out to me by SS CS.

Since my SS is 230v(which essentially halves the start/run currents), I have never had start up issues(other than #3).

#4 is usually over looked as a problem, but if either a long time or distance separates turn on instant from previous turn off instant, the potential increases.

A benefit of turning it down, is to help distribute the oil along the sheave shafts.

Unless there is an indication of a problem, I would not be concerned about not turning the speed down prior to powering it off except the last time during a 'session'(last time before leaving the shop.....). Good idea to leave it set to slow speed between sessions.

[dusty]

The start up currents for most of our shop equipment items is significantly greater than the run currents but if you are using a time delayed breaker that should not be a problem.

I have posted the following sometime in the past but I could not find it so I'll post again:

9086