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

Posted: Wed Jul 24, 2013 6:30 pm
by ai-yo
Hi, I'm new to Shopsmith. In fact, I'm still considering purchasing one. While doing research, I came upon the following tidbit in one of Shopsmith's online manuals, in the "Table Saw - Basic Cuts" section:

[INDENT]Caution: Never turn the speed dial when the Mark V is stopped. You could damage the speed changing mechanism. Always turn the speed to “Slow” before turning off the machine.[/INDENT]

Seriously? I can understand not changing the speed dial when the machine is idle, but having to speed it up and slow it down every time you turn it on and off? So if I rip a piece of wood, turn off the saw and adjust the fence, I have to slow the speed down before I turn it off? In the demos I've watched on YouTube they don't seem to be doing this.

Advice, anyone?

Thanks!

Posted: Wed Jul 24, 2013 6:43 pm
by Gene Howe
Never turn mine down to power off. Hasn't caused any problems for 35 years.
Well OK, sometimes I forget to turn it on and decrease the speed before using the band saw.:eek:

Posted: Wed Jul 24, 2013 7:08 pm
by apexsunguitars
I took that to be a CYA safety caution, undoubtedly they had someone fire it up at max RPM and get hurt...

Posted: Wed Jul 24, 2013 7:16 pm
by billmayo
An excellant safety warning. If you have been sawing and the next time or day, you connect the bandsaw, you would quickly know why turning the speed to SLOW is recommended. I find doing this when quitting my shop time works really well for me. I have gotten a few bandsaws to replace the tires when this does occur. Even had a few bandsaw covers damaged when this occured.

Posted: Wed Jul 24, 2013 7:17 pm
by terrydowning
And when the SS first came out in the fifties many many houses only had 15 amp fuses/breakers to use.

If you're on a 15 amp circuit the breaker may trip if not on slow.

Switched mine to a 20 Amp and have not had that problem since.

Posted: Wed Jul 24, 2013 7:40 pm
by woodburner
Just make sure that you turn it down when switching from one mode to another. Can save a lot of damage on all SPTs.

Also make it a routine for your end-of-day shop list. Just check the speed dial when closing up shop and make sure it is on slow before you turn out the lights. It is easy to forget what the speed was set on when you have been out of the shop during the work week and return the following weekend.

And don't forget the most important thing, make sure your Shopsmith is running when you change the speed, or you will be fixing that pesky little porkchop on the speed mechanism the next time you're in the shop (for those of you who still don't have a PowerPro just like me).

Posted: Wed Jul 24, 2013 10:08 pm
by joshh
ai-yo wrote:[INDENT]Caution: Never turn the speed dial when the Mark V is stopped. You could damage the speed changing mechanism.[/INDENT]
That part is an absolute must!


I know that part wasn't your question but since I made this mistake myself :eek: I had to say it

Posted: Wed Jul 24, 2013 11:04 pm
by WmZiggy
If you change blades, say from a rip or crosscut to a molding head or dado blade I think it's better to move up to the recommended speed rather than rapidly moving it down. Dado blades are less critical, but a molding head spinning at 3400 rpm would make me real nervious. The same is true for sanding disks which are not perfectly balanced for high speeds. Consequently I have gotten in the habit of turing the speed dial down after finishing one task and setting up for another.

Thanks!

Posted: Wed Jul 24, 2013 11:41 pm
by ai-yo
Thanks for the advice, everybody! :)

Posted: Thu Jul 25, 2013 1:18 am
by JPG
One gotcha that was not mentioned. If you move the SS with it set to a high speed, the belt can drop down and get jammed if the control sheave opens up when jarred.

The older 3/4 hp models have less startup torque and starting up at high speed takes longer. That extra time leads to more heating which can build up if frequent start/stop cycles are done. Attached giz whizzes can also affect startup time. The steel sanding disk has considerable inertia.

The speed control can safely be moved if the pulleys are being rotated by hand. Adjusting the speed control towards slow is the critical operation. The torque required to turn the speed control knob is an indicator. Do not force it! Either move the knob slowly, or move, then stop as it gets harder to turn. The latter is more relevant when rotating by hand.

I do not turn the speed down always, but the SS is seldom moved and I am in the habit of checking speed when mounting slower spt's. When I need to adjust it slower after attaching said spt, I do so by jogging(on/turn dial/off repeat til slow enough). I do this quickly enough so the speed never gets critical. Keep in mind mine is a 230v model so startup current is lower, although total power consumed is the same but it does startup quicker than 115v motors due to less 'line loss'.

The SS will tell you when you need to do things differently(heat/delay/stalled).