View Full Version : Lathe button colors

08-28-2009, 01:56 AM
A seemingly trivial question, but I think about it every time I look at my lathe, so to put my OCD to rest, I've decided to risk abuse and ask:

The color of the start button for the forward direction is yellow, and the color of the start button for the reverse direction is green. This seems backward to me.

I'd be grateful for an explaination before I go rewire it.


Jim Shaper
08-28-2009, 02:02 AM
Should be able to just switch the button faces.

Yellow is reverse on my mill, and green is forward - but that's my button choices due to the VFD which runs it.

IMO, lathes shouldn't have buttons for direction; it should be lifting or lowering the arm on the carriage. :)

08-28-2009, 03:55 AM
Unfortunately the faces are not easily changed, so if it contiunes to bug me I'll just swap the switches.

In case I was not clear, I was refering to the spindle directions. I have no lever to change the spindle directions on my apron.

Perhaps you meant to add that to your wish list.

08-28-2009, 06:25 AM
To me, green is forward, yellow reverse, but i'm a little OCD too :o


Weston Bye
08-28-2009, 07:46 AM
Having built a multitude of machine controls and operator control stations (pushbutton boxes), I vote green for forward, yellow for reverse. Red for stop - mandatory and preferably oversized and extended head. This last for the possible colorblind operator - an additional visual cue.

J Tiers
08-28-2009, 08:36 AM
Colors are minor.

The start button(s) should be shielded by a raised rim, or set below the surface of the plate, while the stop should be raised.

The idea is that if you slap the face of the control panel, you should stop the machine.

08-28-2009, 08:49 AM
It would probably be simpler to reverse the motor wiring than the switch wiring. The switch position would then be more logical as well.

If it is a three phase motor, this is a 50/50 chance when reconnecting or relocating a machine. If this is the case, simply switch two of the power leads.

08-28-2009, 09:15 AM
It's CDO, properly alphabetized:D

08-28-2009, 09:36 AM
It would probably be simpler to reverse the motor wiring than the switch wiring. The switch position would then be more logical as well.

If it is a three phase motor, this is a 50/50 chance when reconnecting or relocating a machine. If this is the case, simply switch two of the power leads.

That's what I was thinking - maybe during installation the leads got "reversed" so the yellow button became forward. I don't know about you folks, but every time I wire up a 3-phase motor, it always runs backwards. I know it's a 50-50 chance, but I always seem to be on the losing side... :D

John Stevenson
08-28-2009, 10:06 AM
To me, green is forward, yellow reverse, but i'm a little OCD too :o


So what's pink ? :rolleyes:


08-28-2009, 10:45 AM
So what's pink ? :rolleyes:


E-stop faded over time by sunlight through the shop window ???:D

Unless you're in the dreary part of Merry Old England where the sun never shines....;)

Hey, BD..... You cut any metal lately???:D
Seriously though, if the lathe is 3 ph, it's wayyyy easier to switch 2 live feeds in a plug than rewire 2 switches. My lathes have all had fwd and reverse either side of center on a lever switch except the one that has no reverse. On the only lathe that has buttons and a lever switch, green is fwd jog...

08-28-2009, 04:50 PM
So what's pink ?:rolleyes: The pink button is found on certain types of 'machinist support unit' and is used to relieve the serious and sometimes dangerous stresses that can build up over a period of neglect.

Sometimes the operator will find his ears aching, and encounter general harrassment of one sort or another.

Unfortunately for the operator, the system has never been perfected, so repeated pressing of the button is usually required, often over many, many minutes. (Under very frosty conditions this may take much longer...) Sometimes the button may be hard to locate.

The effort expended is usually worthwhile - the unit will perform much more sweetly afterwards.

There are apparently battery operated devices which perform a similar function, but these are unlikely to benefit the operator in the same way.


Jim Shaper
08-29-2009, 12:35 AM
You guys need to get out of the shop more - the pink button is how you turn your wife on. :D

08-29-2009, 12:40 AM
If there is a 50:50 chance of getting something right, I have about a 80:20 change of getting it wrong the first time.

08-29-2009, 03:17 AM
Lots of good humor here :)

This is not a 3Ph motor.

After seeing a few responses to my seemingly trivial question, I figured I was in for some grief for asking yet another stupid question...thanks for limiting the abuse. One thing you will learn about me, being Braindead: I am NOT afraid to ask a stupid question :eek:

Here's another one: I've seen machinists use lube with a live center. Is this a normal procedure? Is it used just in case there is some relative movement between the work and the center?

Camdigger: why is it always you Kanooks causing trouble??? :D
NO, I have not yet made my first chip, but I AM getting closer!

08-29-2009, 02:29 PM
The pink button is used to call the wife for coffee, at least that's how mine is wired up :D

PS - If it were wired that way, it would soon be red with my blood :D

tyrone shewlaces
08-29-2009, 04:35 PM
I'm betting that some desk-sitting engineer came up with the button color scheme on purpose, and here's why:

When you're looking at the business end of a lathe spindle, "forward" is counter-clockwise and vicey-versie. Since everybody knows that counter-clockwise is always the backward direction, then it gets the yellow color and clockwise gets green. If the lowly machinist thinks they need to be reversed, then he has to fill out a TS-16949 change request in triplicate so a blue-ribbon-senior-engineering-panel-task-force can review it and make a decision. It is in the works and may be corrected by late 2015. This takes a very long time because there are several dozen powerpoint presentations to create first.

08-30-2009, 02:10 AM
Hi All,

This response is not on topic to the OP but I thought it might be informative for some :rolleyes:

I also design control systems in my business, both large and small, and I am in the process of upgrading my LeBlond lathe's controls. I will be adding a VFD in the future but for now I will be using the existing single phase motor with some new controls to do what I want. As for the control layout it will be as follows: A three position switch for Forward / OFF /Reverse, A large mushroom head pushbutton for STOP (red cap), 2 shrouded/recessed push buttons - 1 green for RUN and one yellow for JOG, the direction of run and jog determined by the three position switch. I will probably add an Emergency stop system to dump both the lathe and mill if activated, this will probably be a overhead cable that is available in all operating positions and slightly beyond the operating areas as to be available to others in the shop in the event of a major problem. The just of this design is to be simple, functional and expandable (VFD).

This is just what I think is good others thoughts will differ :p

Input welcome,


08-30-2009, 02:27 AM
Do you plan on implementing your controls via PLC ?

Jim Shaper
08-30-2009, 02:32 AM
Bd, the vfd can act on ladder logic type inputs. You can run many of them on momentary pulses and then the stop button breaks the "continue command" loop.

Some of mine will even cycle through various different presets from a single input device (momentary switch or what have you).

08-30-2009, 02:38 AM

No PLC for this. It is simply WAY to small of an application for a PLC. This application will be two 4 pole contactors, one relay, three push buttons and one switch. The best part is that everything is in stock and leftovers from projects already built and billed :D :D

When I get it done if you want the pictures and drawings I will post them for everyone.