Degree indicator disc for your lathe

[Gritineye]

Here's my effort, it works very well and locks the spindle solid, but if you have a disconnect pin to your chuck for the back gear, a little play may happen there. One way of preventing that is to hung a weighted strap over the chuck to add tension, and only turn the chuck one way.

 

[DAPPH]

Ouch no that's not right. An 8" disc will have a circumference of 638mm (and change). More importantly, marking one degree at a time will introduce compound errors. Just 0.01mm out each mark and your last mark will be 3.6mm out of position. This is why dividing heads are so widely used.

Dividing or direct-indexing even from a paper print is the best option.

Sorry I didn't explain fully " the multiple " a diameter of around 8" will give you 360 degrees 2 mm apart . D = C / Pi

Therefore D = 720 mm / 3.14159. so D = 229,2 mm ( nearly 8 " ????) though I'd have written it out on paper instead of typing /using the guessimate of the earlier post

Anyway Pete ,
Thanks for pointing it out just in case I'd missed it or made a mistook , as I'm quite dyslexic some days and would never ever see anything wrong with my figures at the time. now I have the timing disc I'll play with that taking my point of aim at the middle of each degree line thickness .

Edit ...
If I perceive I need a more accurate disc I've just realised I can use the gears that came with the lathe to set up a compound train where I can get one degree per tooth ( I think )

Here's my effort, it works very well and locks the spindle solid, but if you have a disconnect pin to your chuck for the back gear, a little play may happen there. One way of preventing that is to hung a weighted strap over the chuck to add tension, and only turn the chuck one way.

Just seen the last picture.. that's a good idea if you want to copy a decent sized gear & have the gear in question .. I want to make a 16 tooth gear with the major diameter of 3/4" which equates to 22.5 degrees . I'm pretty sure I don't have anything less than 20 teeth but I suppose I could use a 32 or 64 tooth gear and paint the teeth I need to lock up at .

 

[Gritineye]

DAPPH, your Sphere has an improved cross slide and saddle, I'm waiting for one of those to turn up to fit onto mine!

Yes I numbered the dial later, the dial is my design and has center locking for zeroing. would you like some pics of how it was done?

I milled a new traverse gear case and new gears and shafts, all on my Atlas. I was my first attempt, and I didn't get the form tool ground quite perfectly as you will see, but it works fine

having trouble uploading so bare with me re pics.

 

[Gritineye]

Numbered dial...

 

[Gritineye]

I'm pretty sure I don't have anything less than 20 teeth but I suppose I could use a 32 or 64 tooth gear and paint the teeth I need to lock up at .

Yep that's the way to do it, any gear that divides right will do, the bigger the better!

67823[/ATTACH]

 

[DAPPH]

Yes please show me how it is all done .

I have a problem Huston ....
The cross slide and compound handles are zinc based metal & are pinned to the shafts the pins look like parallel pins with a ribbed centre waist to hold them in place as both ends of the pins are flush witht eh handle body and they look the same size from either side. .. I've tried to gently remove them using some hardened fine parallel pin punches but the buggers won't move .. next step is a cardboard box over them with a 100 watt incandescent bulb inside lit for four hours to expand things a bit & try again.

In post 24 what size is that oil hole screw diameter on the cross slide in thousandths of an inch or as an imperial fraction of an inch ( mine are missing ) I don't have a set of thread gauges , any fine taps other than metric ones nor am I sure if it is supposed to be the numbered thread size ie old SAE sizes or UNF or ANF or any other size .

I have an Atlas MOLO circa 1942/43 which covers the 10 F lathe , it has the thread charts innit so I should be able to find a suitable thread to try and cut if you'd be so kind & let me have the imperial & metric dimensions of it .
.....

 

[Wedg1e]

Basic idea, but a mandrel in the rear of the headstock with your pin and you can use as many different gears as you have.

From the Workshop Practice Series book 'Dividing', by any chance?

 

[Wedg1e]

Wedg1e, my engineering brain is pre-decimal.

Ah, so groats, ells and cubits for you then...?

 

[DAPPH]

More like cabbages ,cows , crows , corn & sand grains

Basic idea, but a mandrel in the rear of the headstock with your pin and you can use as many different gears as you have.

Waaaaaaah !
I want me Mummy .
" Mummy , Mummy I want a mill for Crimbo , can I have one can I , can I , can I ?

 

[gordon stephenson]

Wedg1e, I last used cubits when i was building the pyramids.

 

[gordon stephenson]

I have never had to make a degree disc, But during my working life if anything was expressed in degrees, I could do my mental calculation to convert it to distance measurement, easy peasy.

 

[CRB]

From the Workshop Practice Series book 'Dividing', by any chance?

Harold Hall.

 

[Wedg1e]

Harold Hall.

That's the fella.

 

[DAPPH]

I have never had to make a degree disc, But during my working life if anything was expressed in degrees, I could do my mental calculation to convert it to distance measurement, easy peasy.

Due to two strokes my necktop computer is often found to be running as slow & confused as the labour party , so it's modernise and use the degree disc
/wheel for me m'lad .

 

[AndyStobbs]

Due to two strokes my necktop computer is often found to be running as slow & confused as the labour party , so it's modernise and use the degree disc
/wheel for me m'lad .

You think yours is slow, I just spent 30 seconds trying to make the connection between engines and brain speed.

 

[MattF]

Harold Hall.

He's a member on here too, is he not?