View Full Version : Knobs

11-29-2003, 10:27 PM
I like knobs. I had a minor epiphany this afternoon while making a knob. I think one of the major things that distinguishes machinists from everyone else is that we like knobs. I have been programming since 1963. I bought a new gas stove a few years ago because it was the very last one with a knob to set the temperature of the oven. I don't freekin want to program my oven to cook some food. Just set the knob to 325 and be done with it. Thank you. I like knobs. When I have nothing else to do (not in this life) I make a knob. I like things with lots of knobs, the more the better. I have a microwave with no knobs. I hate it.

While I am on the subject of knobs I thought I would show you a knob. I made it this afternoon. Due to my perhaps inordinate fondness for knobs I am willing to spend inordinate amounts of time making one. I don't recall who mentioned this but I made this knob using the bull gear on the spindle of my SB9 (took the guard off). I made a very simple indexing attachment and used a 60 degree thread cutting tool turned sideways to cut the grooves.


G.A. Ewen
11-29-2003, 10:33 PM
Damn, you're good! http://bbs.homeshopmachinist.net//wink.gif

[This message has been edited by G.A. Ewen (edited 11-29-2003).]

11-30-2003, 12:10 AM
Knobody can deny your creativity.

Paul Alciatore
11-30-2003, 12:33 AM
I like knobs too. The one you made is a work of art.

I work in TV and electronics and have found that there has been a trend towards buttons on digital equipment instead of knobs or sliders (they're cheaper). In my opinion, there are many things that are far easier and faster to do with a linear control instead of by typing numbers or simple up/down controls. In this human interface area, a lot of digital stuff has taken a large step backward. I've seen experienced operators take several minutes to make an adjustment with buttons that they could and have made in seconds with knobs or linear controls.

The digital world has it's equivelent of the good old fashioned knob. Graphic computer languages have on screen slider controls. There are rotrary encoders that act like a digital pot. There'a the ever popular joystick which is a form of knob (just a few degrees of rotation each way but it is rotation), etc. It's just that it's often easier and cheaper to implement the simple numeric or up/down push buttons. And the knobs just look old fashioned.

Paul A.

11-30-2003, 01:31 AM
<font face="Verdana, Arial" size="2">Originally posted by Evan:
I like knobs. (snip) I have a microwave with no knobs. I hate it.</font>

My microwave (15 yr old Panasonic), and my parent's microwave (23 yr old Amana "Radar Range") still have knobs, and I like them that way! I hate using the microwaves at work. The BEST VCR remote control I ever saw was also made by Panasonic. Instead of Up-Down-Left-Right buttons, it had a knurled knob/button, which worked just like the scroll wheel/middle button on your mouse. You could fly through the menus! When my VCR gave out, I went looking for Panasonics just for the remote, but they did away with it. I ran across the same scroll knob/button on a friend's old Motorola cell phone, and once again you could zip through all of your cell phone menus and entries, as fast as you could spin that wheel! Of course they did away with that feature also! It seems this generation of human interface designers just dont get it!


11-30-2003, 01:41 AM
I must wonder who at South Bend decided to make the bull gear 76 teeth. That number has perhaps the least number of factors of any even number under 100. 38, 19, 1. Why didn't they select 60 or 80? Good for knobs though.

11-30-2003, 01:57 AM
Nice knob. I agree with you. I like the knobs in my truck on the lights, radio and the heater/AC. Hate the push buttons on my wife's car. The worst thing they ever came up with though is the numbered menu when you call a business. When I make a phone call to any business, I want to talk to a human.

Paul Alciatore
11-30-2003, 03:32 AM

I suspect they choose the number of teeth to provide an odd ratio and allow every tooth on it to mesh with every tooth on the back gear an equal number of times. This type of gear construction allows the wear on the gear teeth to even out or average out the same over all the teeth of each gear thus avoiding local areas where the teeth lead or lag the average position by some small amount. If you will notice, the other side of the back gear is likewise an odd ratio that brings every tooth of one into every tooth of the other. These kinds of ratios are not possible with nice even numbers.

But it would have been nice if it had, say, 72 or 96 teeth as they could/would provide a method of indexing on the headstock. Perhaps they just didn't think of it. Or perhaps they even wanted to prevent that.

He did use the bull gear to divide for the knob. Lets see, it has 76 teeth and the prime factors are: 2, 2, 19. That gets you 2, 4, 19, 38, and 76 divisions. It sure could be better. 72 would give you prime factors of 2, 2, 2, 3, 3 and would allow divisions of 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, and 72. Much better and almost the same number of teeth.

Paul A.

11-30-2003, 03:53 AM
Yeah Paul, I left out the number "2". Duh. However, I have some really nice high precision gears that will fit on the register behind the chuck with just a bit of machining. I think I can manage that. I am planning on making a dividing head of some sort with 360 teeth. That has a lot of factors. He he. I must think of a way to hold a drilling tool accurately on the milling adapter to drill a plate...

Something will come from this, I assure you.
As soon as I finish my current project I am building a vacuum pump and a vacuum faceplate, then a dividing head, then... Crap.. too long a list. But then it would suck to have too short a list. I am happy.

11-30-2003, 09:50 AM
Does this register a momentary twinge of a reality check with anyone? Thanks for the compliments, I appreciate it very much. All of you inspire me to do better work. You realize I made a knob and what it takes to do so. What could be more taken for granted in life than a knob (don't answer, that was a rhetorical question)? Has the average person ever looked at a knob and thought "Wow, that tool and die maker sure is talented!". I don't think so. Sigh. It's early and I need to do some very quiet machining.

BTW Paul, you are most likely correct. 60 teeth would be nice though. The Babylonions thought so.

[This message has been edited by Evan (edited 11-30-2003).]

11-30-2003, 10:17 AM
Nice! How did you do the coloring?

11-30-2003, 10:19 AM
Coloring? That is a reflection.

11-30-2003, 10:23 AM
The Babylonians had 60 teeth? Wow. Factoid for today.
The Atlas lathe has 60 indexing holes on the face of the bullgear and a pin on headstock to index.
Instead of fitting a gear to the register, make an expanding mandrel to fit the outboard end of the spindle bore. Attach the gears here, and rig an indexing latch on the back of the headstock for indexing. You will find it much handier.
A lot of people also install a crank on the mandrel to use for hand threading to a shoulder, etc.
I must admit that my interest in knobs lies in a somewhat different area. I do appreciate a nice balanced handle though.

Paul Gauthier
11-30-2003, 10:25 AM
Nice Knob

Paul G.

11-30-2003, 01:58 PM
The Babylonions invented the concept of zero as a point on the number line. They also used 60 as a number for enumerating many things in their daily life because it has the greatest number of factors of any value under 100. Why do you think there are 60 minutes in an hour?

BTW, JC good idea.

[This message has been edited by Evan (edited 11-30-2003).]

11-30-2003, 06:22 PM
Isn't the rim a different color (blue) than the front (white/shiny), or am I making that up? It looks to me as though the rim is dark blue, and you maybe took a skim pass across the front after coloring it to make the front white/shiny.

Anyway...it looks nice!

11-30-2003, 09:05 PM
Evan: Georgeous work once again !

I'm also fond of knobs, having been a religious HP fan most of my life. Even now, it's damn hard to beat an encoder wheel for data entry and precise cursor movement. Mice and touchpads suck for instrument use (IMHO of course). My next project is getting an encoder wheel because the prior generation used accelerated softkeys and even when done well, they just don't compare.

12-01-2003, 12:46 AM
Nice work Evan.

clever how you did that.

12-01-2003, 01:48 AM
I was going to compliment you on your knob too, but if your wife isn't going to, I sure as hell won't. http://bbs.homeshopmachinist.net//biggrin.gif

Nice job.

12-01-2003, 02:03 PM

I hate mice. I use an optical trackball. Way better than a mouse. Really good for computer games.

12-01-2003, 10:52 PM

Interesting knob, nice project.

I like knobs, handwheels and levers. I really like machines with the levers with the black plastic balls.

Are you going to add a graduated backplate to your knob? A tapered disk about an inch larger in diameter with graduations would look really great.

I use a Microsoft optical trackball. I really like it.


[This message has been edited by BC21OSH (edited 12-01-2003).]