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View Full Version : what is this on my lathe?



Black Forest
12-31-2010, 12:11 PM
What do you think these dials or whatever they/it is for on this lathe?
http://i853.photobucket.com/albums/ab91/burnandreturn/dial_lathe.jpg

2ManyHobbies
12-31-2010, 12:15 PM
I would guess at least one of them is a threading dial. Do they move in concert, or does one move and the other stays steady when the carriage moves under leadscrew power?

RobbieKnobbie
12-31-2010, 12:16 PM
They're clocks... one tells minutes to coffee break and the other minutes to lunch.

Very popular feature on production equipment. That nice flat surface just above to the left was originally fitted with a coffee mug holder... home shop versions came with a beer cozy instead.

DannyW
12-31-2010, 12:19 PM
Those are the forerunners of digital scales!
Their name escapes me, but I guess others will chime in.

Regards,

Danny

J Tiers
12-31-2010, 12:22 PM
Assuming there is nothing mating with the leadscrew, probably something similar to a "Trav-A-Dial" in the US. if so, it reads carriage movement via a wheel contacting the face of the way.


I see a mark that looks like where teh wheel has traveled along the way. might do both inch and metric.

Black Forest
12-31-2010, 12:29 PM
I have not actually seen the lathe yet. I bought it over the telephone. I am hoping to have it delivered next week.

I emailed the "former" owner and asked him what it is, but no answer yet.

Alistair Hosie
12-31-2010, 01:06 PM
I second trava dials.Now all the lathe needs is a nice clean /and or coat of GREEN paint happy new year to you all.Alistair

oil mac
12-31-2010, 01:38 PM
Trava -Dials, They were used a lot over here, until recently, (sadly not a lot of lathes round every corner in all sort of factories nowadays)

I am a bit puzzled that there is two of them on the lathe, wonder if one reads metric &one imperial measure? In the days when they were in vogue, they were an expensive item, Still a handy accessory.

MuellerNick
12-31-2010, 01:53 PM
Now all the lathe needs is a nice clean /and or coat of GREEN paint

With the pressure washer. :D

Doesn't look at all like a thread dial. Trav-a-dial sounds better. The second scale is maybe for coarser resolution.

Martin might be out for a party...
Nick

Black Forest
12-31-2010, 01:58 PM
It seems I sent the email to Martin but forgot the attachment. He answered back right away. "What red box"

spope14
12-31-2010, 03:43 PM
Looks like older Trav-a-dials. As I recall, the top one measures inches, the bottom one thousands of an inch in the Z axis (carriage) travel.

John Stevenson
12-31-2010, 03:59 PM
Soviet equivalent of the Trav a dial. Do not have any factual proof but I'm sure they had these before the American version.

I'll go with the dual dial sysyem but they used enclosed dials, the early Trav-a-dials used a cheap large scale.

http://www.stevenson-engineers.co.uk/files/early-travadial.jpg

They definitely had the optical reading system on machine tools before the west

Mcruff
12-31-2010, 04:25 PM
Trav a dial's came out in the early 1960's, never seen a Russian version. To me they are easier to use than readouts. They are every bit as accurate as DRO's though, at least down to about .0005 per couple of feet , I remeber checking one on a Leblond many years ago that was within .001 over its 60" bed travel, not bad for a wheel rolling on metal.

Dr Stan
12-31-2010, 05:21 PM
Yes it is a Travel Dial and they were the best thing since sliced bread until the invention of the DRO. Sure made life easier in holding accurate lengths, especially those in excess of 6".

Stan

oil mac
12-31-2010, 06:30 PM
Was there not an issue with the wheels on the travadial being affected by dirt &oil on the surface on which they ran, Thus causing errors being found in the measurements, I seem to recall something about that some years ago?

Can somebody enlighten me

John Stevenson
12-31-2010, 06:53 PM
Not sure Mac, the wheel that runs on the bed is slightly curved, straight knurled and hardened.

The curve is so you can tilt it and 'adjust' the circumference to get the accuracy needed and the knurling leaves tiny marks a la' a rack on the bed so it has a positive drive.

Years since I have used / owned one but they are nice on long bed lathes where scales are very expensive.

lane
12-31-2010, 07:05 PM
Those are Trav a dials the tell how far the carriage moves . Never seen one with 2 dials all of mine just have one dial and one looks like a dial on a combination lock. i have a model 7A with just one dial that has 2 hands you touch your tool to the end of your part set the inch dial to 0 the turn the dial backward till the next hand reads 0 and now you can know how far the carriage travels

lane
12-31-2010, 07:13 PM
oil mack they can skip if you let chip between the sponge gasket and the bed . just keep things clean and oiled and they work great . 0005 in the length of the bed is possible just takes some care in mounting and adjusting them.Have them on my own lathes and at work. lot better than read outs . No cables to get caught in a wad of stringy chips.

hardtail
12-31-2010, 07:27 PM
Soviet equivalent of the Trav a dial. Do not have any factual proof but I'm sure they had these before the American version.

I'll go with the dual dial sysyem but they used enclosed dials, the early Trav-a-dials used a cheap large scale.

They definitely had the optical reading system on machine tools before the west

These were French made I believe.......pre DRO

http://i509.photobucket.com/albums/s337/corn56/100_0189.jpg