MACHINE SWITCH

Topics include, Machine Tools & Tooling, Precision Measuring, Materials and their Properties, Electrical discussions related to machine tools, setups, fixtures and jigs and other general discussion related to amateur machining.

Moderators: GlennW, Harold_V

User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: MACHINE SWITCH

Post by Harold_V »

whateg0 wrote:I do strive for perfection, though, in everything, keeping in mind that not everything needs to be perfect. Sometimes good enough really is good enough. But, I've seen and bought machines and tools before that somebody had said was in great shape but was really cobbled together and thought, man, whoever did this was a real hack! I don't ever want to be that guy, now or after I'm dead.
Yep! I understand that perfectly well. In fact, I am the proud owner of a used B&S surface grinder that has experienced rework by someone who has no clue. The table bed was rescraped, introducing nearly .005" error over its length. Table now rocks as it traverses side to side. I will rescrape in the future. The grinder was purchased off ebay, and shipped coast to coast for less than the value of the machine, so I am not complaining, although I must admit, when the problems were discovered, I had assumed I made a huge mistake in buying. Turns out to not be the case, however.

One of the other errors made was upon assembly. The anchor point for the hydraulic cylinder and cross feed screw were in the wrong attitude. It was off so far that the vertical column tilted as it approached the far side of travel. Took a while to determine what the problems were, but I can see a VERY nice grinder in my future, assuming I rectify the mistakes made by the unknown individual. I would not enjoy having others think I was responsible for such glaring errors.

The comment about knowing when "good enough" is good enough. I have memory of returning framing studs to the saw when as little as 1/64" was removed. And I wonder why it took us almost 20 years to complete our house and shop? :oops:

Harold
Wise people talk because they have something to say. Fools talk because they have to say something.
User avatar
SteveHGraham
Posts: 7788
Joined: Sat Jan 17, 2009 7:55 pm
Location: Florida

Re: MACHINE SWITCH

Post by SteveHGraham »

Harold_V wrote:I would not enjoy having others think I was responsible for such glaring errors.

The comment about knowing when "good enough" is good enough. I have memory of returning framing studs to the saw when as little as 1/64" was removed. And I wonder why it took us almost 20 years to complete our house and shop? :oops:

Harold
I use a 25" outside micrometer to set studs. It hasn't been calibrated in a long time, though.
Every hard-fried egg began life sunny-side up.
shorttrackhack
Posts: 42
Joined: Sun May 15, 2011 4:38 pm
Location: SoCal

Re: MACHINE SWITCH

Post by shorttrackhack »

I feel for you about the 10 page manual with your VFD. Using your existing switches with a Hitachi, Yaskawa, Allen-Bradley or Danfoss level of drives would be doable with the options they have. I also have some old Bronco, Bodine and KBs, which are much more rudimentary in control circuit options. The latter usually lack the option for three wire control.
User avatar
Harold_V
Posts: 20231
Joined: Fri Dec 20, 2002 11:02 pm
Location: Onalaska, WA USA

Re: MACHINE SWITCH

Post by Harold_V »

SteveHGraham wrote:I use a 25" outside micrometer to set studs. It hasn't been calibrated in a long time, though.
Heh! Novice, and a tight-wad. That's what you are. All of our studs are on 16" centers, and the mic I used was recently calibrated. There's no way I'd trust stud spacing to an unknown mic. One can't be too careful. :P

H
Wise people talk because they have something to say. Fools talk because they have to say something.
whateg0
Posts: 1114
Joined: Sat Mar 28, 2009 3:54 pm
Location: Wichita, KS

Re: MACHINE SWITCH

Post by whateg0 »

I have a friend who actually does all of his woodworking with a mic, although I **don't think** he'd use them when building his house.
Ironman1
Posts: 36
Joined: Sun Jun 04, 2017 6:36 pm

Re: MACHINE SWITCH

Post by Ironman1 »

I have three VFD's in my shop and they work flawlessly, but maybe because I read all the instructions.
A VFD should be controlled from the 24 volt control system or else the push buttons on the panel, to turn on and off the load. Once the load is shut off the main power to the vfd can be shut off. I use a automotive toggle switch to control the VFD and a magnetic switch to shut off the vfd power after the load is shut down. They will fail if you repeatedly turn them on and off from the power source.
The larger units 5hp and up, will run on after shutting off power til the internal capacitors are drained. Up to that point there is power available to shock you if you are playing with the innards.
On some things like the gear head drill press, I leave the vfd on 24/7, and the foot pedal switch controls the 24 volt control circuit. So far that vfd has not been shut off for 5 years.

The nicest thing about the vfd is the programmable braking on shutdown, and the ability to wire in a small potentiometer and spool up your rpm by changing frequency. I can change the mill spindle speed from 315 to 3400rpm by turning a knob, and have it stop rotating in 5 seconds.
Formal education will make you a living;
Self education will make you a fortune.- Jim Rohn

"Opportunity is missed by most people because it is dressed in overalls and looks like work." Thomas Edison
whateg0
Posts: 1114
Joined: Sat Mar 28, 2009 3:54 pm
Location: Wichita, KS

Re: MACHINE SWITCH

Post by whateg0 »

Ironman,

Some of that is specific to the VFD, I think. As in, I have a cheap VFD. I'm not sure what you mean by turning on and off the load. I have read the instructions for my VFD, all 26 pages of them. There's not much there. My VFD doesn't have a 24V control connection anywhere.

I'm also not sure what you mean when you say that the VFD will fail if repeatedly turned on and off from the power source. How else do you power it down? Isn't that what your mag switch is doing?

I'm taking advantage of using a pot in place of the 10ee's original wire wound pots to control the VFD frequency. Unfortunately, I can't make use of a braking resistor with this VFD. While it was sold as having the capability, they lied. I bought this in anticipation of this lathe's revival and didn't actually try to use it for several months. No big deal, one day when I buy a better VFD, this one will find a home on the bandsaw or the mill where stopping on a dime isn't a necessity.
Post Reply