Making Graduated Dials

[Mark_f]

Several people have asked how I make such perfect looking graduated dials with numbers, so I wrote this short article to explain the simple process I use. To start with, I made a simple fixture from some aluminum that will hold the number stamps aligned to stamp the numbers evenly and in line. The next photo is a print to make this fixture.


The next several photos show the fixture and how it is mounted in my lathe.


You can see in this photo the two 6-32 SHCS with springs to hold the block tight against the stamp when inserted in the proper slot. (The hole in the main block is not needed. I made my fixture from scrap materials on hand and the hole happened to be in the block). There are two slots that match the two sizes of stamps that I have.





The above photo on the right shows the fixture in a QCTP holder. (You can see the set screw marks where it can be mounted in different orientations to suit the stamping job requirements).



I have made the dial for my lathe cross slide conversion. It is 2" in diameter Most of the time when I make a dial, it will have a lock screw tapped hole for locking in position. I will put a set screw in this hole to lock the dial to the shaft for engraving the lines.

The above photo shows the setup for marking the lines. I set the dividing head on the rear end of the lathe bed and clamped it in place. (I will be making a permanent base to mount the dividing head on that will fit on the lathe base just for this purpose). The dial is mounted on a piece of 1/2" drill rod mounted in a collet at the head stock (the collet is not tight) and a collet in the dividing head (this collet is tightened). A boring bar with a sharp 60 degree tool is set up to engrave the lines.



The above photo shows the indicator set up to measure how long each line is made using the lathe carriage. In this instance the thousandth line will be .125" long, the five thousandth line will be .175" long, and the ten thousandth line will be .250" long.

The vector arms on the dividing head are set so that there are 8 holes to every move. Using a 20 hole plate, this will give 100 divisions in one full rotation of the dial to be engraved.

I have started marking the dial. this process takes about 30 minutes. The lines are engraved .006" deep.

The lines are complete. The next step will be to use a file to clean the burrs off the dial by removing the dividing head and mounting the dial in the lathe spindle on a shaft in a collet. After cleaning the burrs, the next operation will be to stamp the numbers on the dial.



The numbers will be stamped next.......

 

[Mark_f]

If you don't have access to a dividing head the lines can be engraved in a similar fashion by using a degree wheel on the lathe spindle, but it is more difficult because you have to position the wheel yourself and it can be hard to read the proper increment. I used to do it that way before I had a dividing head. The dividing head gives perfect spacing and is ALMOST idiot proof. Another method would be to use a gear with the proper number of teeth to set up a make shift indexer on the lathe.

 

[Mark_f]

The last step to making a nice dial is stamping the numbers. The dial is mounted on a shaft in a collet. The outward end of the shaft is center drilled and supported with a center in the tail stock. This is very important to keep the setup solid when banging the stamp with a hammer.


Next the burrs are removed with a file and the dial is polished. The lines came out uniform and perfect.



The stamping fixture is mounted on the QCTP and lined up the the long line that will be zero. A pointed rod that fits the stamp hole is used for this. with the line at the top of spindle rotation, the point of the tool is lined up to the line. The carriage is positioned to the number location and LOCKED in position.


This is a close up of lining up the fixture.


The zero is stamped above the line. Since there will be two numbers on the rest of the dial. The next number which will be "10" in this instance, will be stamped. turn the spindle by hand with the "0" punch in the fixture until the number end of the punch is just to the right of the next long line. Stamp the number by giving a sharp bang with the hammer. ( practice this first on a sample to get used to how hard to bang and always try to hit the same each time ). Insert the next number , "1" in this instance, and rote the spindle by hand until the number lines up just to the left of the line. Stamp the number. Continue this process around the dial.

This is a simple process but you have to learn to watch the spacing to keep all as close to the same as possible.



When finished, use a fine smooth file to remove the metal raised by stamping and polish the finished dial. Once set up, the stamping process only takes about 15 or 20 minutes.


AND THAT IS HOW I MAKE GRADUATED DIALS!

 

[Cavediver]

Thank you Mark.

Two questions for you.
You say you engrave to .006 deep. Is that done in one pass, regardless of the material? (That's my assumption, but I would hate to be wrong on my first attempt at this!)
What type of file do you use to knock down the burrs? I know little to nothing about files; that's something I need to fix, and knowing what the professionals use would be a great help! (I know you're not actually an industry professional, but the caliber of your work ALWAYS says otherwise to me.)

 

[Mark_f]

Thank you Mark.

Two questions for you.
You say you engrave to .006 deep. Is that done in one pass, regardless of the material? (That's my assumption, but I would hate to be wrong on my first attempt at this!)
What type of file do you use to knock down the burrs? I know little to nothing about files; that's something I need to fix, and knowing what the professionals use would be a great help! (I know you're not actually an industry professional, but the caliber of your work ALWAYS says otherwise to me.)

Actually I am an industry professional. I was a master machinist and then an engineer for a major machine tool manufacturer. Now I am retired. But to answer your questions, yes the engraving is done in one pass. I use a Nicholson "smooth" cut file to clean the burrs. You want to use a "fine" file. You don't want to scratch up your dial or you will sand off the numbers polishing it back up. Feel free to ask anything you want to know. I will help all I can.

 

[Cavediver]

Whoops! Sorry for the sleight! I knew the engineer part, didn't know about your status master machinist!
I'm getting ready to fettle a HF "Milling Vise" and I'm going to try to make some new dials for that one, which is practice for adding a new hand wheel to my lathe leadscrew, which is practice for...
(I'll eventually get around to that Phase II table, but I need to complete a few smaller scale skill builders first!)

 

[Silverbullet]

Well now I have another use for my Gulledge too. Thanks Mark , I hate the tiny ones on my logan. I often thought of selling and finding a little bigger lathe with readable dials . But with all the tooling I have I'd go broke selling to replace.

 

[woodchucker]

Those numbers are beautiful. That set must be practically new or very high end. Very nice work as usual.
let me ask, is there any risk to your 9a since you are hitting the dial with a hammer blow. iknow not too heavy, but still it is a quick rap.
What about your mandrel... ? will it damage the mandrel?
I did mine like Mr Pete, off the lathe. But I like how yours came out.

 

[Mark_f]

Whoops! Sorry for the sleight! I knew the engineer part, didn't know about your status master machinist!
I'm getting ready to fettle a HF "Milling Vise" and I'm going to try to make some new dials for that one, which is practice for adding a new hand wheel to my lathe leadscrew, which is practice for...
(I'll eventually get around to that Phase II table, but I need to complete a few smaller scale skill builders first!)

No problem........ Let me know if I can help you in any way

 

[Mark_f]

Those numbers are beautiful. That set must be practically new or very high end. Very nice work as usual.
let me ask, is there any risk to your 9a since you are hitting the dial with a hammer blow. iknow not too heavy, but still it is a quick rap.
What about your mandrel... ? will it damage the mandrel?
I did mine like Mr Pete, off the lathe. But I like how yours came out.

This has been a long argued topic on many forums and I don't intend to argue the point with anyone. I been doing this for a lot of years. That little hammer bang is not going to hurt the lathe. If you were going to make hundreds of dials , I would say make a special fixture but for just a few, it don't matter. I mount the dial on a solid shaft or make a mandrel. It is VERY important to support the outer end with a center in the tail stock and try to keep it short so the load is absorbed by the tail stock also.. That little hammer bang is less than some interrupted cuts. if someone disagrees, they are free to do it their way.

My number set is a cheap Chinese set I bought somewhere online for less than $10. I believe it is a 1/16" number height.