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Kai
02-11-2010, 11:45 PM
I think most will pass this one over but please don't.
I am really new to all this and have heard this many time but I just do not know really what it means. No I 'm not taking the mick I am that new to this cnc stuff.
if there is a ref to this please point me to it and I will read it I am getting back into learning and really enjoying life again and this is a great place to get help I was told by the chap I got my machines from.

Wobblybootie
03-11-2010, 09:59 AM
Sorry ... not a phrase I am familiar with. Unless it refers to using a DTI to 'clock' tolerances or distances. I do remember an instructor telling me to 'clock' the backlash of a mechanical joint to ensure it was within a given range. Hope that helps (but I am probably wrong).

Kai
03-11-2010, 11:05 AM
No I think you are on the same page as me.
I only used the term as thats what the chap called it when he set up a job in a milling machine.
I think it is the same as making sure the job is flat or as needed when starting a job or getting the lathe part right in the jaws.
It's this process that I am looking for a how to and tips on and also what dials etc or gauges you need or what is recomended.
As I said this is a whole new thing to me and just want to learn whats what

i2i
03-11-2010, 11:23 AM
Hi Kai, clocking is what you think it is. A "Dial Test Indicator" (clock/dti) is an indicator that shows physical movent on a dial. We spoke about this on the weekend, but i'm sure you've forgotten most of what was said.:smile:
The most common use on the mill would be, setting the vice up so that it's square to the x axis. You do this by clamping a parallel (or piece of flat metal) in the vice jaw and setting the clock to show the amount of movement along the face of the parallel when you move the x axis. You then adjust the position of the vice so that there is zero movement on the clock from end to end of the parallel.

i2i
03-11-2010, 11:24 AM
ps. feel free to give me a bell if you're not sure about anything.

Tom.

Robin Hewitt
03-11-2010, 07:24 PM
Or do you mean electronics? Clocking then means rattling a line up and down, usually between 0 and 5 volts, in the hope that something on the other end of it will understand and do something useful.

Kai
04-11-2010, 12:15 AM
Thanks Tom I was not sure of your id on here lol.
I do remember quite a bit of what we talked about, I just comes to me at differant times to when I need it lol
I spoke to the tutor at college and he said we can use the machine ther to help make the base for the vice there if needed.
I think I will need to call you because I can not remember how you told me the best way to make it was lol I know it had two dowl pins and a stop on the bed but after that I did sort of lose it. The drive back was a little tought the traffic getting out of cardiff was hell an hour and a half before we hit the motorway. But both machines will be up and running soon.

i2i
04-11-2010, 10:18 AM
there was probably a match on, that's why the traffic was bad. Give me a ring anytime and i'll explain it for you.

05-11-2010, 02:14 AM
Clocking: refers to the use of a Dial Test Indicator (also sometimes abbreviated to DTI, or referred to as a "clock" or "clock gauge", hence the term "clocking").

For example, to "clock a vice" on a milling machine: set the vice up approximately with the T-slots on the machine table and *gently* tighten the nuts (not fully, you'll need it to move slightly). Lightly trap a parallel in the vice.
Using a DTI / clock (or whatever you like to call it), set a zero on it with the DTI "finger" at one end of the parallel, then wind the table across so your gauge ends up at the other end (still with me?) and record the error. If required, GENTLY tap that end of the vice away from the DTI finger, by about half of the error (ie, if you have an error of 0.2mm, tap the vice until you get about 0.1mm reading).

Repeat this process until you get minimum or zero error (if you get a zero error reading, make sure the finger is still in contact with the parallel).

Your vice is then "clocked", ie it is aligned with the machine table, and you can now set up your workpiece in the vice.

Yell if you're struggling with my explanation - it's a difficult subject to explain in words: it's far easier if you can get someone to show you to be honest.

Hope that helps.

Kai
05-11-2010, 11:09 AM
Yes that make sense to me thank you for that.
All I have to do now is find a resonable good one for not a lot of money lol the story of my life at the moment.
Any suggestions any one ? Will I be able to use the same DTI with the lathe I have as well?

i2i
05-11-2010, 04:53 PM
you can use it for both machines, and the only real difference in them is whether you go for the finger type or plunger type. The plunger has more movement, but the finger type is more versatile. i would go for the finger type and a good magnetic stand.

Kai
05-11-2010, 05:29 PM
thanks for that I will have a look around to see whats around

06-11-2010, 06:09 PM
Have a look at the Draper Tools website (or catalogue if you have one), stock number 46609, catalogue page 361.

This is rated by Draper as "Expert Quality" (ie, suitable for professional use). It contains both types of "clock" (plunger clock for 0-25mm) and a "finger" or stylus clock 0-1.5mm as well as a magnetic stand with fine adjustment and a range of tips for the clocks. I reckon this kit would cover just about every milling and turning need you have. Accuracy is quoted as 0.01mm.

Currently priced at around £82 (don't know your budget so don't know if its in your price range) but for the money you probably won't go far wrong with it.

http://www.draper.co.uk/catalogue/Alpha/Alpha-D.html

Hope that helps.

andykett
13-11-2010, 04:01 PM
The "dti" I use is a verdict one which are brill but you will be fine with most makes. Kennedy are normally a reasonable price. There are lots of different types so have a look. You can use on both milling and turning centers but you will need to buy either a magnetick base or normal clock/surface guage base to use on the lathe. hope this helps!!

Kai
21-11-2010, 11:55 PM
Thanks for all the advice I got a cheap value finger DTI and a spi plunge DTI and a mid range mag base.
I thought it was going to be a lot harder than it was to get to grips with these things but I think I am finally getting the hang of this stuff lol.