# Why do you have a TS DRO?



## skiprat (Aug 23, 2012)

This is a question that has puzzled me since I saw the first tailstock DRO here. Don't get me wrong, I think they 'can' be useful, but I was wondering if most people are actually getting better results than simply doing it the old way by making a mark in the drill bit? 

What point are you using as the Zero reference? 
Please look at the sketch. You can see that if you wanted to drill a hole to a certain depth, then the zero point is important. 
If you choose A or C, then at what point do you zero the DRO?
If you choose B ( edge of existing hole ) then surely the difference between the existing pilot hole and the finished size would alter the depth. 

The other thing that I wondered about is that most DRO's on calipers that I've seen, automatically switch off after a few minutes to save the battery. What do you do if it switches off, half way through your drilling. 

Like I said, I think they 'can' be useful. I just wonder how most people are using them. :biggrin:


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## nativewooder (Aug 23, 2012)

Genetic defect?!:biggrin:  Don't even know what DRO stands for!:redface:


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## mredburn (Aug 23, 2012)

I use "C" as for my depth Zero almost all the time. There are a couple of instances where I use "A" but rarely. The DRO,s wont shut off when they are in motion if they work correctly, they are supposed to only shut off due to inactivity. I use them for drilling front sections when making my wooden pens.

@ Barry dro=  Digital Read Out


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## jd99 (Aug 23, 2012)

I don't use one, I use dykem and scribe a line on my drill bit. that way I dont have to keep zeroing out the DRO when I change drill bits. :biggrin: And I use "C" as my start of Dim. 99% of the time.


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## PTownSubbie (Aug 23, 2012)

I do like Mike with my reference point. I use Pt "C" most of the time. 

I use mine to get more accuracy when making front sections for my fountain pens. There are so many different depth and size requirements if you make it a snug fit. I first started off figuring out how far the drill bit turned per revolution of my tailstock handwheel. But since Mike (BluWolf) installed mine for me when I visited, it was inexpensive enough that I popped for it. It makes things better, I believe. 

Besides, I didn't want to have to continue to mark my drill bits.....


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## PaulDoug (Aug 23, 2012)

Sure glad you asked the question Skiprat.  I have been pondering that sense I saw one someone set up (I think I saw it here) on their lathe.  Great set up but it got me wondering about the zero reference.


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## Sylvanite (Aug 23, 2012)

I usually index off point "A", but that's because I do a lot of step-drilling.  Without any visual reference, I just slide the tailstock in until the bit makes contact and count revolutions of the handwheel for depth.  I don't typically mark the bit (so I don't have to worry about redoing it when I sharpen the bit), but there is one blind drilling operation I do where I have to fully retract and clear the bit a couple of times.  Since I can't reset to zero, I drill to a mark on the bit.

Regards,
Eric


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## skiprat (Aug 23, 2012)

Ok gents, it seems most use point C on the bit. I do too, but I mostly mark the drill bit with a Fineliner Sharpie. If I need precision, then I drill a little deeper and then face off the material and use a vernier until the depth is spot on. ( If I'm boring a hole with a boring bar, then I use the dial on the hand wheel irrespective of whether the cutter is in the tailstock or the topslide toolpost )
With a mark on the bit there is no need to zero anything, so at what point do you zero the DRO? .
It would seem that you'd have to drill a bit till point C is flush with the blank before you could zero it. 

Thanks for answering guys:biggrin:


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## skiprat (Aug 23, 2012)

mredburn said:


> ...... The DRO,s wont shut off when they are in motion .....


 
Good point Mike. I forgot about that. LOL, you can tell I don't have a TS DRO fitted !!


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## Dalecamino (Aug 23, 2012)

Good question Steven. I use my DRO for drilling the depth of the tenon I've glued my cap bands on. I line up the bit with the openingof the blank (letter C in your illustration) then zero the DRO there. Has always worked for me, so far.


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## John Den (Aug 23, 2012)

Hello Skip.
All I can say is :- I felt like you do now BEFORE I fitted my TS DRO.
Now I don't know how I did without it.
As far as "A,B &C" is concerned I usually drill until "C" is flush with the front of the job, then press zero.
I don't find the DRO switching off at the wrong time.
What I do find annoying is the way the new scales automatically reset Zero on switch on. Most times I'd rather it retained the last zero setting like they used to do before some clever S*d redesigned them!
Rulers and Felt tips are alright but they usually don't quite fit in the space available AFTER you've set up the TS position.
Another thing I find useful is, just before I withdraw the drill to clear out the swarf, I read off the DRO reading so that I can wind back in again fast, to just before the reading and not crash into the bottom of the drilling with disastrous effects.
Regards,
John


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## bluwolf (Aug 23, 2012)

Convenience. It's quicker than marking a drill bit. Granted, if it was a real expensive item, I'd still be marking drill bits too. But for $28 ($25 when they're on sale) it's well worth it to me. As for it ever shutting off on me, at least the ones I use, they have memory so when I turn it back on it's still where I left it.

Mike


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## skiprat (Aug 23, 2012)

Sometimes when I'm drilling to a specific depth, and need to keep things cool, I prefer to loosen the TS and whip it out rather than winding back the crank. My mark on my bit will always remain but a DRO  would lose it's reference.  Drilling a hole deeper than the  TS quill travel ( a closed ended pen ) and you'll be reaching for the marker again:biggrin:

I can understand all the pro's and con's of them. I just wanted to know from others how they were coping. 
To each his own I guess.


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## Mack C. (Aug 23, 2012)

nativewooder said:


> Genetic defect?!:biggrin: Don't even know what DRO stands for!:redface:


All the jabber, jabber and this question was never answered!:redface:


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## skiprat (Aug 23, 2012)

mredburn said:


> I use "C" as for my depth Zero almost all the time. There are a couple of instances where I use "A" but rarely. The DRO,s wont shut off when they are in motion if they work correctly, they are supposed to only shut off due to inactivity. I use them for drilling front sections when making my wooden pens.
> 
> @ *Barry dro= Digital Read Out*


 


Mack C. said:


> nativewooder said:
> 
> 
> > Genetic defect?!:biggrin: Don't even know what DRO stands for!:redface:
> ...


 
Sure was:wink:
Unless you mean 'Genetic Defect?' ? 
I dunno


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## Mack C. (Aug 23, 2012)

skiprat said:


> mredburn said:
> 
> 
> > I use "C" as for my depth Zero almost all the time. There are a couple of instances where I use "A" but rarely. The DRO,s wont shut off when they are in motion if they work correctly, they are supposed to only shut off due to inactivity. I use them for drilling front sections when making my wooden pens.
> ...


Sorry; Looked all over, racked my brains, couldn't figure it out!

DRO = digital read out. It's in my brain forever!


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## mredburn (Aug 23, 2012)

Maybe its Geriatric defect.:biggrin::biggrin::biggrin::biggrin:


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## PedroDelgado (Aug 23, 2012)

I have 2 DROs, one on my Milling machine and one on my metal Lathe. I don't just make pens so when you want accuracy, repeatability, precision and consistency on your projects (I am sure some of these words mean the same so pardon the ”redundancy”) ; DROs are the way to go. Mine do not shut off as they are working on 110 Volts.
Happy turning!!!


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## 76winger (Aug 23, 2012)

I'm with Nativewoodworker: Don't know what DRO is.

ETA: after reading posts directly above, I half-know what it is. I assume this Digital Read Out is measuring the Dept of travel on the tailstock rather than motor speed, eh?


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## BigShed (Aug 24, 2012)

Like many people, and not only those on this forum, I have a tailstock DRO on my metal lathe, as well as a 2 axis DRO for the X and Y axis.

I also have a DRO on the quill of my mill and since 2 days ago I have DROs on the X and Y axis of my mill.

Like most here I use "C" as my reference, but of course Skip your question doesn't only apply to a tailstock DRO, it also applies to where you measure from to put the mark on your drill bit, doesn't it?

I used to use the mark on the drill bit method and found it not very accurate, also the mark often gets obscured by the swarf coming out of the hole you are drilling.

I even have a digital read out on my tablesaw, a Wixey, and on my thicknesser, so I guess you could say I like DROs.


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## skiprat (Aug 24, 2012)

BigShed said:


> Like many people, and not only those on this forum, I have a tailstock DRO on my metal lathe, as well as a 2 axis DRO for the X and Y axis.
> 
> I also have a DRO on the quill of my mill and since 2 days ago I have DROs on the X and Y axis of my mill.
> 
> ...


 
Fred, my whole object is around *drilling*. Any other machining operation is a mute point because you invariably are using a flat bottom or flat side of the cutter as your reference point. When milling, you simply bring up the cutter till it just touches the work (even with the machine off ) set your zero, back up a bit, switch on and away you go.

If you zero your TS DRO once you have judged or eyeballed the point C being flush with the work, then how can it be said that it is more accurate than the same person judging or eyeballing a mark on a drill bit? 
As for the repeatability statements, how does that work??? You can only drill the same hole once. The next hole again depends on where the point C estimated. 
Both methods are only as accurate as the operator. :biggrin:

Right, it's a long weekend here in UK and I have a couple of pens to make for some contest or another. :wink:


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## jd99 (Aug 24, 2012)

Think about this....

Before the first DRO was ever built, and to make the prototype; someone was making the precision parts for the DRO without a DRO. Hmmmmmmmm


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## IPD_Mr (Aug 24, 2012)

I use to use sharpies to mark my drill bits. Problem is, the Mrs. never let me have the new sharpies because I would press to hard and over time they became double broad points.  :redface:  This did not work too well when needing to do some step drilling as my marks were not accurate.  I would make the mark and measure the bit again to the mark so I knew if I needed to stop just into the mark or towards the back of the mark and so on.


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## skiprat (Aug 24, 2012)

IPD_Mr said:


> I use to use sharpies to mark my drill bits. Problem is, the Mrs. never let me have the new sharpies because I would press to hard and over time they became double broad points. :redface: This did not work too well when needing to do some step drilling as my marks were not accurate. I would make the mark and measure the bit again to the mark so I knew if I needed to stop just into the mark or towards the back of the mark and so on.


 
Oh Mikey, Mikey, Mikey  The answer is simple.....

...use some of the money you have ripped off from your father in law and buy new sharpies. :wink:


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## IPD_Mr (Aug 24, 2012)

Well if he would buy more I would.  I think I have made enough to afford the cap.


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## skiprat (Aug 24, 2012)

Mike, while you're saving up for the rest of the pen take a look in the Sharpie cap. They out-sell any other big manufacturer except maybe Bic by about a gazillion billion to one. How many threads are in it??:wink::biggrin:


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## mredburn (Aug 24, 2012)

:devil:Keep him entertained boys, if hes gabbing here he isnt making any pens.:devil:


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## IPD_Mr (Aug 24, 2012)

skiprat said:


> Mike, while you're saving up for the rest of the pen take a look in the Sharpie cap. They out-sell any other big manufacturer except maybe Bic by about a gazillion billion to one. How many threads are in it??:wink::biggrin:


 
Oh yeah this from a guy who's cap is red and threaded. Thanks SKIPPY :tongue:

(Ooops I forgot to sign this)

regatrds,
TAM


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## Ed McDonnell (Aug 24, 2012)

Am I the only one that counts the number of turns on the tailstock handle to control depth?  Each turn is 0.0625".  An eighth of a turn is ~.008".  I haven't hit a situation yet where that wasn't good enough.  Especially when the starting point is just eyeballed.

So, maybe with a DRO you never lose count.  But with counting you never forget to set zero.  With a sharpie you don't have to count or worry about setting zero, but how accurate is that line drawn on the drill bit?

Ed


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## jd99 (Aug 24, 2012)

parklandturner said:


> how accurate is that line drawn on the drill bit?
> 
> Ed


 It depends on the line, if it drawn with a sharpie not very, if its a scribed line on some layout fluid then it can be with in .005".

I used the scribed line method for 20+ years in the tool and die trade never had any problems, in the old days if the hole depth was critical and has to be controlled precisely then it would be bored or drilled on a jig boring machine. Now the cnc machines have ball screws and steppers that they can control them really close.


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