# Analog read out



## student_Machinist (Aug 14, 2010)

Hey guys
Just wondering if any one uses dial indicators on their lathe/mill cross slides as a kind of analog read out?
Pics would be appreciated as i would like to get some ideas be for i try this my self.
thanks in advance
Jonathan


----------



## DICKEYBIRD (Aug 14, 2010)

Here's what I use on my lathe. 1st a 2" indicator for the carriage:












A 1" on the cross feed:






Another 1" on the tailstock: (This was several years ago; I recently installed a cheap 4" digital caliper on the tailstock)


----------



## Royal Viking (Aug 14, 2010)

Jonathan, I was wondering the same thing myself after having to use my magnetic mount several times.

Dick, thanks for the examples. How did you cut the v groove for the bed mount on the carriage travel? I have a southbend and I can make most things. It looks like I would have to resort to a hand saw and file to do that.

Roy


----------



## d.bick (Aug 14, 2010)

Colchester lathe cross slide dial indicator.

I have fitted a dial indicator to my Colchester lathe.
 Some of the features to look for are the dial is mounted on a moveable block adjusted by a knurled wheel which moves the dial back and forth by a rack and pinion. The cross slide cannot damage the dial by crushing it because there is a screw between the lathe cross slide carriage and the block which pushes the dial along the rack before the full limit of the dial is reached.


----------



## shred (Aug 14, 2010)

Royal Viking  said:
			
		

> Jonathan, I was wondering the same thing myself after having to use my magnetic mount several times.
> 
> Dick, thanks for the examples. How did you cut the v groove for the bed mount on the carriage travel? I have a southbend and I can make most things. It looks like I would have to resort to a hand saw and file to do that.
> 
> Roy


I have a carriage travel indicator made out of a 4" Starrett I picked up at a garage sale. Looks a lot like the first pic from dickeybird except mine has thumbscrews (handy for repositioning if you have a longish bed lathe). I cut the v-groove by tilting the block at 45 degrees and running an end-mill across it.


----------



## black85vette (Aug 14, 2010)

My solution was a quick and dirty one.  Needed something quickly and never went back to make it look nice.  Just took a scrap piece of aluminum and a couple of magnets. Milled out a pocket for the magnets and epoxied them in place.

I put it on the rail in front or behind the carriage depending on what I am doing.  Don't have to worry about bottoming out the DI and damaging it. The magnet just gets pushed back by the carriage.

For longer work I have a 24" digital scale that I have mounts for. Any more the cheap digital scales are competitive with a DI.  Plus they zero at any point with just a button push.


----------



## Deanofid (Aug 14, 2010)

I only use them on the carriage travel, since that is the only axis that doesn't have
dials. (If the slide has a dial, I use it!)

First attachment is on the Taig, and mounts to the depth stop. Can be moved
where it's needed that way.

Second attachment is on the Atlas, and clamps at any position needed.


----------



## student_Machinist (Aug 14, 2010)

Deanofid  said:
			
		

> I only use them on the carriage travel, since that is the only axis that doesn't have
> dials. (If the slide has a dial, I use it!)


to be perfectly honest I'm 17 and have had to teach myself how to use all of this stuff. Consequently i haven't been able to get my head around using the dials effectively ??? (any help would be appreciated)

One problem that i have is that I live in a land of metric measurement that for some reason does not have any suppliers that sell dial indicators with travel over 25mm for a reasonable price. So the main question i have is is it worth doing for such a small amount of travel? i suspect this would be more of a problem for the mill as i cant afford a DRO and prefer analog measurement.

btw thanks every one for the rplys and pics.


----------



## miker (Aug 14, 2010)

Student machinist, have a look here....

http://www.ctctools.biz/servlet/Categories

Where are you located on planet Earth??

here...

http://www.ctctools.biz/servlet/the-457/PRECISION-MEASURING-GAUGE-LONG/Detail

edited to add direct link to Dial Indicators.


----------



## Deanofid (Aug 14, 2010)

student_Machinist  said:
			
		

> to be perfectly honest I'm 17 and have had to teach myself how to use all of this stuff. Consequently i haven't been able to get my head around using the dials effectively ??? (any help would be appreciated)



This is good to know, and helps us answer questions. You can get a lot of help from people here. Just try to include any info in your questions that you can think of. One of the things that will help is knowing where you live, so others can suggest suppliers applicable to your location and measurement system.

You don't need to put your street address. Just a country and state, if you have states. (A first name would be nice, too. There are already a few people here called "Student"-something.)

It would be nice of you to put an introduction in the "Welcome" section so we can hear a bit about you and your interests, too.

So, what troubles are you having with reading your dials? Also, what is the calibration of the dials, and what measurement?



> One problem that i have is that I live in a land of metric measurement that for some reason does not have any suppliers that sell dial indicators with travel over 25mm for a reasonable price. So the main question i have is is it worth doing for such a small amount of travel?



Dial indicators over 25mm, or 1" travel start to go up in price more than they seem to be worth. That's just the way it is.
A 25mm dial indicator (DI) can be quite useful. Think about how often you may need to make shafting over 25mm in length that need accuracy better than 1mm, and you'll probably find that it isn't too often. If you need to make very close measurements along a diameter that is substantially longer than that, you can always move the DI down the lathe bed in increments of 25mm to get a longer measurement. 
That's how I do it on my Atlas if I need more than an inch, which isn't too often.

For instance, if you need to measure 75mm along the length of a piece, and using a rule or caliper isn't accurate enough, move the carriage 25mm, lock the carriage, move the DI down the bed and zero it, and do the same again until you have your full length. If you're worried about getting mixed up on your setups, write down the increments and add them up.

You can also use a 150mm electronic caliper to give you an increased range. Look at some of the other pictures here for how to do one of those.

Dean


----------



## DICKEYBIRD (Aug 14, 2010)

Royal Viking  said:
			
		

> How did you cut the v groove for the bed mount on the carriage travel? I have a southbend and I can make most things. It looks like I would have to resort to a hand saw and file to do that.


I cut the groove with an endmill & the part clamped on the mill on a tilting table.

Someone mentioned knurled knobs to adjust the position. I tried that initially but it slipped a few times so I replaced it with a SHCS tightened by a T-handle allen wrench. She don't move no mo'. ;D

Also about the "If the slide has a dial, I use it!" thing I wish I was that good. Dummy me had a lot of trouble trying to figger out what to do with the backlash when making adjustments and kept screwing up parts. That's when I put the clocks on all axes, with the plungers bearing right against the carriage & cross slide. End of problem and I don't have to think so hard.


----------



## student_Machinist (Aug 14, 2010)

miker  said:
			
		

> Where are you located on planet Earth??



New Zealand


----------



## shred (Aug 14, 2010)

DICKEYBIRD  said:
			
		

> Someone mentioned knurled knobs to adjust the position. I tried that initially but it slipped a few times so I replaced it with a SHCS tightened by a T-handle allen wrench. She don't move no mo'. ;D


Slipping is a feature ;D If I run the carriage into the indicator it'll slide along the bed before doing any damage. My thumbscrews are six 1/4" ball end-mill scallops around the edge of some 3/4" stock, so I can reef down on them pretty good too. I'm not sure a regular knurl would be fun to tighten enough to keep it from moving.


----------



## miker (Aug 14, 2010)

Direct link to CTC Dial indicators.

http://www.ctctools.biz/servlet/the-457/PRECISION-MEASURING-GAUGE-LONG/Detail


----------



## Deanofid (Aug 15, 2010)

DICKEYBIRD  said:
			
		

> Also about the "If the slide has a dial, I use it!" thing I wish I was that good. Dummy me had a lot of trouble trying to figger out what to do with the backlash when making adjustments and kept screwing up parts.



Oh, it's not anything to do with being good, Dick, (and you're no dummy!). I sure didn't mean for
it to sound like a brag, if that's how it came off.
Just a matter of knowing your machine has back lash, and dealing with it. It's been done for over a
century, and if the old heads could do it, so can we.

If you back out your slide, take the dial past the backlash inherent to, or that's worn into, the machine.
Then, when you return to your original setting, the slide will be back where you expect it should be.
You can readily feel the backlash in most machine dials, and every machine that has regular lead screws has it, whether brand new, or a model from decades back. 

Dean


----------



## student_Machinist (Aug 15, 2010)

Deanofid  said:
			
		

> So, what troubles are you having with reading your dials? Also, what is the calibration of the dials, and what measurement?


the main problem i have is that the dial on the cross slide increases in slightly unusual increments (0.04mm or something) so i have a bit of trouble keeping track of how far i have gone (btw I'm a bit dyslexic which doesn't help much)


----------



## Mainer (Aug 15, 2010)

I've got a 1" travel indicator on the carriage and find that 1" travel is adequate for nearly everything I do.


----------



## steamnut2010 (Aug 15, 2010)

Good day mate.


----------



## Deanofid (Aug 16, 2010)

student_Machinist  said:
			
		

> the main problem i have is that the dial on the cross slide increases in slightly unusual increments (0.04mm or something) so i have a bit of trouble keeping track of how far i have gone (btw I'm a bit dyslexic which doesn't help much)



I'm pretty curious. What kind of lathe have you got there? And, "0.04mm or _something_"?
What are the increments, exactly?

Maybe give us a picture of the dial, that shows the "or something" part. Hopefully, someone can help.

Dean


----------



## student_Machinist (Aug 16, 2010)

Deanofid  said:
			
		

> I'm pretty curious. What kind of lathe have you got there? And, "0.04mm or _something_"?
> What are the increments, exactly?
> 
> Maybe give us a picture of the dial, that shows the "or something" part. Hopefully, someone can help.
> ...



My lathe








this is the caliper i used for my tailstock




my mill





Sorry if these pics dont turn out right
btw please excuse the mess ;D


----------



## Ned Ludd (Aug 16, 2010)

What mess?
Ned


----------



## Lakc (Aug 16, 2010)

Each mark on the dial is .04mm. Took me a second to figure that out myself. If you force yourself to use the dials, you will probably get real good at counting by 4's rather quickly.


----------



## steamnut2010 (Aug 16, 2010)

One of the more confusing things I have had to learn as a newby is how to use the dials on the lathe and mill.

I started out with the eyeball method, and then used calipers to see how close I was every so often. This method definitely does not work well.

Then I started using the crossfeed dial, but that was way off for some reason. Then I figured out that on my lathe, 0.001" on the crossfeed dial will cut 0.001" off of both sides of a round piece, for a total cut of 0.002".
I have read machining books, but lathe types vary, and dial types vary, and until you get in there with some test (hopefully inexpensive) stock, it is hard to get a feel for your equipment.

Then I started looking at the lathe carriage dial, confident that it was just like the crossfeed dial (not!). It measures in 0.004" increments. Who makes these darn things and what were they thinking?

So here is what I do, and I am not sure if this is correct or the best way to do it, but a newby-made-up way, but I rough a piece out and get a size approaching what I need. Then I rotate the crossfeed handle to make a light cut, and set the crossfeed adjustable collar to zero when I do this.
I then measure the work with a micrometer or a good caliper.
Lets say I measure the diameter of the work at 2.35", and I want 2.25" for a final diameter, then I use (2.35-2.25) divided by 2 or turn the crossfeed dial in by 0.05, or 50 increments on the dial that has 0.001" increments.


----------



## steamnut2010 (Aug 16, 2010)

I actually turn the dial slightly less than 50 increments, since it is not easy to un-cut a piece once it is too small. Also, I noticed that once you polish a piece, the piece gets slightly smaller, and for a critical fit, this is no good.

For the carriage dial, I again make a fine face cut, and then set the carriage adjustable collar to zero.
I measure the thickness of the piece in the chuck, and assuming the same dimensions as the first example, say the piece measures 2.35" thick, and I want to face it off so that it is 2.25" thick, then I take 2.35"-2.25" = 0.1"
Divide 0.01" by 0.004" which equals 25 increments you have to turn the carriage dial. Since the carriage dial is making a face cut off of one side of the material only, unlike a rotating cut on a round piece, then you do not need to divide by 2.

One website suggests that if you need a fine final cut on the crossfeed, set bit where it touches the work (not while it is running), and then use a piece of shim stock between the carriage stop and the carriage, say 0.001".

I have to remember to remove the carriage stops, otherwise I jam the carriage shortly after the above step.

I highly recommend a newbie go through the steps to learn the dials using some test stock. It is a pain, but a very valuable learning step. Now, I can start with a rough piece of stock, make a few rough cuts, set the dials as described above, and bingo, I am spot-on. The time to make an accurate cut is reduced by a factor of at least 10, not to mention it is much more enjoyable to take the guesswork out of it, especially when using expensive stock like brass.


----------



## mklotz (Aug 16, 2010)

> Then I started looking at the lathe carriage dial, confident that it was just like the crossfeed dial (not!). It measures in 0.004" increments. Who makes these darn things and what were they thinking?



It may be that you have a metric screw and a dial marked off in (approximate) Imperial graduations.

A 1 mm pitch screw would advance 0.03937" in one revolution. Divide that by 100 marks on the dial and you have 0.003927" per mark. Now, round that off and you have 0.004" per division.

This means that the dial is in error by 0.04-0.03937 =~ 0.0006" per revolution or six thousandths in ten revolutions.

You can check the pitch of the screw with a pitch gage or, alternatively, put a DI on the carriage and see how far off it is in ten revolutions of the handle.


----------



## steamnut2010 (Aug 16, 2010)

So now, confident in my newbie method of using the dials on the lathe, I try to use the dials on the mill.
Surprise surprise, yet again another system for the mill dial, with a range of 0 to 12.5.

I always expect the dial to read 0-10 for some reason.
I have learned to ignore the total dial range, and pay attention to the increments, i.e. each mark on the dial equals either 0.001" or mm, or 0.004" or mm, and pay attention to whether you are cutting off of a diameter of a round piece, or making a face-type cut.

Then just use the procedures above, and dial in the correct increments.

Another thing I had to practice on (with inexpensive stock) is keeping track of my decimal places. At first I would calculate a dial rotation of say 20 increments, and would rotate only 2, or vice versa.

Anyone newbie can sit down and master the dials in an afternoon.
Make notes and hang it next the the machines until you have it memorized.


----------



## steamnut2010 (Aug 16, 2010)

The vetran guys have used the dials for so long that they don't even think about exactly what they are doing. It is just natural for them, but I can vouch for the fact that the first time you do it, it can be awkward.


----------



## steamnut2010 (Aug 16, 2010)

The mess in your photo is actually much cleaner than when I started out.
I did not even know you were suppose to be neat and organized until I saw photos of other people's lathes.
Neatness has been a learned thing for me, but it makes it easier for me to be neater.


----------



## steamnut2010 (Aug 16, 2010)

From a previos post:
It may be that you have a metric screw and a dial marked off in (approximate) Imperial graduations.
A 1 mm pitch screw would advance 0.03937" in one revolution. Divide that by 100 marks on the dial and you have 0.003927" per mark. Now, round that off and you have 0.004" per division.
This means that the dial is in error by 0.04-0.03937 =~ 0.0006" per revolution or six thousandths in ten revolutions.
You can check the pitch of the screw with a pitch gage or, alternatively, put a DI on the carriage and see how far off it is in ten revolutions of the handle.


Pardon my ignorance, but just a newbie trying to understand.
If he rotates the dial by 0.002mm, then he should get exactly a 0.002mm cut, right.
For metric threads, wouldn't that be accounted for in the gear ratios, not the dial?


----------



## Deanofid (Aug 16, 2010)

Marv, did you notice the dial says:

Ø 0.04mm

This is a direct readout dial. Whatever you dial in will be how much comes off the diameter of the work piece in increments of 0.04mm.

That's confusing for people who are used to working with dials that normally tell the movement of the slide, which is probably how all the other measurements read out on the other dials of this machine, and on your mill, too.
Now I can see why you want some dial indicators to mount to your lathe! It makes things difficult when all the dials aren't calibrated the same way. Some of these importers should be thrashed!

Dean


----------



## mklotz (Aug 16, 2010)

Dean,

Yes, I noticed. However, as the quote in my post shows, I was addressing steamnut's comment in post #22 about how he found it curious to have a dial marked in 0.004" divisions.

Some of the importers build their products to metric standards and then, for export to the USA, slap dials with imperial calibrations on them. As expected, the results are not pretty.


----------



## student_Machinist (Aug 16, 2010)

Deanofid  said:
			
		

> Some of these importers should be thrashed!
> 
> Dean


I agree completely :bow: The only reason i got these was that i was i got a scholarship from school to get a lathe and mill and these were the only available tools at the time for the right cost


			
				steamnut2010  said:
			
		

> The mess in your photo is actually much cleaner than when I started out.
> I did not even know you were suppose to be neat and organized until I saw photos of other people's lathes.
> Neatness has been a learned thing for me, but it makes it easier for me to be neater.


thanks ;D i'ts been almost 4 years since i got them and i still havent worked out good storage or workbench.
I'm going to have to raise the lathe and mill about a foot as the stands they came on are way to short for me. does anyone know a good way to do this?


----------



## Deanofid (Aug 16, 2010)

Marv, I didn't mean your previous post was incorrect. I just wondered if you had noticed the diameter
symbol on the dial.

If this dial had simply been marked with a radius cut, like many lathes, the divisions would read in 0.02mm, and could have been marked in easy to add slash marks in 10's.

I once owned a lathe that had a mix 'n match dial/leadscrew typical of some far east stuff. The dials read out in .0625" rotations.  I think that lathe made me the ornery person I am today. Drove me mad, too.


----------



## Deanofid (Aug 16, 2010)

student_Machinist  said:
			
		

> The only reason i got these was that i was i got a scholarship from school to get a lathe and mill and these were the only available tools at the time for the right cost thanks



You don't need to make excuses for it. There's nothing wrong with the lathe. It just has a non-machinist friendly cross feed dial. You might be able to buy a dial for it that is graduated in 0.02mm. At least it would be easy to add up the ticks.

Dean


----------



## steamnut2010 (Aug 16, 2010)

Maybe this is a dumb question, but then again, no one has ever accused me of being smart.

But why do they not use the same dial increments on all dials, say 0.001 inches, or 0.001 mm, and have all dials read from 0 to 10?

I remember asking a question in grammar school about why they had the words "to", "too" and "two", and all sounded like "to".
Also "knot", "not", you get the idea.

There must be a locical reason such as the dial gets too big or something.


----------



## Groomengineering (Aug 16, 2010)

Not a dumb question at all. Acme screws on imp. machines are fairly coarse so marking out .001" is fairly easy. Metric thread forms are usually quite a bit finer, .001mm marks would be extremely close together. Metric pitches are also based on a ratio to diameter of the screw instead of a 'real' number i.e. 1/2"dia-18tpi. That's why the dials don't end up 1-10.

Cheers

Jeff


----------



## steamnut2010 (Aug 16, 2010)

Groom-

I think I followed you up to the "That's why the dials don't end up 1-10" point, then I got lost.

I will try again:
My lathe has 0.001" increments on the top dial, and 0.004" increments on the lower carriage dial.
So are you saying they use 0.004" on the lower dial because otherwise, there would be too many increments for the dial.
Why not make the dial larger? Maybe they want to just build one dial for all parts?

When people start taking about screw pitch, I think in terms of gear ratios, and setting the knobs on the left side of the machine to drive the carriage at the correct speed for the desired thread pitch.
But I don't see the connection between the gears and the dials. I can dial any dial at any time independent of the gears, and indeed, some lathes have no gear cutting threads at all.
So how are threads per inch related to dials?

For an example, if I want to cut off 0.1" off of a piece, I just turn the dial the correct number of increments to get a 0.1" cut (that may be a hypothetically large cut). So why not, as with engineering scales, just have the scale run from 0-10?
What you must be getting at is the relationship between the thread on the dial shaft and the reading on the dial collar?
The dial collar readout, ie: 1-10, or 1-12.5, etc. is tied to the thread pitch used on the dial shaft, is that what you are saying?

It's all as clear as mud, but I think I am making progress.
Thanks for your help in understanding.
I guess it should be obvious, but it is not.


----------



## steamnut2010 (Aug 16, 2010)

Here is a photo of my upper dial (crossfeed dial?), not to be confused with the upper dial called I think the compound rest dial.
It appears to have a range of 1-10, increments of 0.001", and also has a separate dial for simultaneous metric measurement.

The photo of the lower dial has increments of 0.004", a range of 0 to 0.58?, and does not have the metric thread.

So if I am looking at it correctly, you can have a range of 1-10 on the upper dial, but not the lower?

Questions, questions.


----------



## kvom (Aug 16, 2010)

The lathes I used in school don't have DROs. To measure along the Z (carriage axis) we use a DI attached to a "MightyMag" holder. For measuring travel greater than the 1' range of the DI, use a 123 block as a spacer.

As an example, suppose you want to turn down some stock for a length of 3.5". Position the carriage at the right end of the stock. Now, position the DI/magnet against the carriage with the tip slightly depressed and zero the DI dial. Move the carriage left .5" by watching the DI needle turn 5 times back to 0.

Then hold the 123 block with the 3" length against the side of the carriage and position the DI/magnet so that the tip is depressed less than 1 full turn (i.e., less than .1"). Zero the DI dial.

Now when you turning down the stock, you can use the DI needle as an indicator as to where to stop. As soon as the needle starts to move, slow down and gradually approach the 0 mark.

This use assumes that there is a spot on the lathe bed or headstock where you can place the DI and magnet parallel to the bed.


----------



## Groomengineering (Aug 16, 2010)

Sorry to muddy it up! ;D



			
				steamnut2010  said:
			
		

> The dial collar readout, ie: 1-10, or 1-12.5, etc. is tied to the thread pitch used on the dial shaft, is that what you are saying?



Yes. The pitch on the feed screw sets the actual movement and the dial has to be marked to accommodate it. From your pics it looks like the "lower" dial is the carriage traverse dial? If so it probably runs a gear on a rack on the side of the bed. My SB doesn't have a dial on that handle, but the feed is fairly coarse so that .004" per mark sounds right. Again, the dial has to accommodate the actual movement so it's not always pretty. 

Hope this makes some sense, explanations are not my strong suite. ???

Cheers

Jeff


----------



## mklotz (Aug 16, 2010)

Maybe an example will help...

Suppose your dial is attached to a shaft threaded 10 tpi. That means that one rotation of the dial corresponds to 0.1 inch movement of whatever the shaft drives (e.g., cross slide). The thread on the shaft has to be relatively coarse else you would have to spin the dial an inordinate number of times to move it a significant difference. That gets tiresome quickly. 

If I want dial divisions that correspond to 0.001", that means I need 0.1/0.001 = 100 divisions on the dial. Let's say that I think, for easy viewing, the divisions should be 0.125" apart so I can visually interpolate 0.0005". That means the circumference of the dial must be 12.5". Dividing by pi tells us that the dial would need to be ~4" in diameter.

A 4" dial is fairly big for a small lathe. (Many small lathes have 4" *chucks*!)

As you can see dial design becomes an engineering trade-off complicated by several human operator concerns.


----------



## Deanofid (Aug 16, 2010)

> When people start taking about screw pitch, I think in terms of gear ratios,



Screw pitch doesn't have to do with the gears. It's the measurement of threads on a screw. In imperial, it is how many threads are on a one inch length of the screw. In metric, it is the distance from one thread to another, measured from a given point on one thread to the same given point on the next thread. In other words, measuring the distance from the top on one thread to the top of the thread next to it. 
Gears are also measured in "pitch", but it is not the same as screw pitch.



> So how are threads per inch related to dials?



A true imperial machine has lead screws for the compound and cross slides that usually run in a pitch that is evenly divided into round numbers for the dials. A screw that has 10 threads per inch, (tpi) will give a nice even 100 divisions on the dial, and they will be marked in .001" increments. On smaller screws, they usually use 20 tpi, which gives 50 divisions on the dial of .001" each. 
On some imperial machines, the lead screw pitch is different on the cross and compound. They still make them so they read in even .001" increments, though the dial on the compound may read 0-50, and the one on the cross may read 0-100. Still dead easy to count the turns of the dial, and on either dial, one mark equals .001", so you don't get mixed up!

For a 10 tpi screw, you know it has to rotate 10 times to move an inch, so each rotation of the dial gives .100", and that's how they mark it. Similar for a 20 tpi screw, but the number of rotations is twice a many per inch. It's all nice and even, which ever screw pitch they use.



> So why not, as with engineering scales, just have the scale run from 0-10?



You can't, unless the screw used is compatible with being divided evenly by 10. Otherwise, you will have increments left over, or not enough to fill the scale. You can't just divide the scale into 100 increments if the screw doesn't move that slide a distance that adds up to 100 of some standard measurement. 

If the maker used metric threads for the lead screws, and wanted to sell to an imperial market, they just cheat and mark the dials in an approximation of imperial increments. They're never quite right, and sometimes are really a mess, as the increments don't always add up to a figure that is easy to multiply in your head. Kind of like the lower dial in your picture, which seems to have .58" per rev. That kind of thing shows up in cross slide travel too, when metric and imperial are mixed.  

You asked why not just make the dial bigger. I guess they can only make it so big. Eventually it would start getting in the way of things, like the dial on the cross slide.

Dean

EDIT: I see I was typing about the same thing that everyone else said. Oh well. Here it is again!


----------



## steamnut2010 (Aug 16, 2010)

Thanks Marv and Dean-

That does shed some light on the dial subject.
I will have to get out the dial indicator and try some of the things you mention, comparing the dial indicator with the dial on the feeds.


----------



## Hilmar (Aug 16, 2010)

Dean


> You don't need to make excuses for it. There's nothing wrong with the lathe. It just has a non-machinist friendly cross feed dial. You might be able to buy a dial for it that is graduated in 0.02mm. At least it would be easy to add up the ticks.



It just has a non-American Machinist friendly cross feed dial. 

If you work with the " cross feed " you don't take off on the length, You take off on the Diameter. If you want to take off .064 you dial it in and not divide .064 /2 = .032 and then dial this in. You dial in what you need. No calculations, Bingo you are done. Easy 
Hilmar


----------



## steamnut2010 (Aug 16, 2010)

Seems like I read where on some lathes, moving the crossfeed dial lets say 5 increments, or 0.005" moves the bit in 0.005", and then on others, moving the crossfeed 5 increments moves the bit in 0.0025", for a reduction in diameter of 0.005".


----------



## Maryak (Aug 16, 2010)

It can be very frustrating for a newbie to machining, I have come across X slide dials marked for diameter reduction but most are for radius reduction.

There is no hard and fast rule other than "Know and understand your machine." and that knowledge comes by playing with it till you are ready to do some fair dinkum machining.

Hope this helps.

Best Regards
Bob


----------



## Deanofid (Aug 16, 2010)

Hilmar  said:
			
		

> Dean
> It just has a non-American Machinist friendly cross feed dial.
> 
> If you work with the " cross feed " you don't take off on the length, You take off on the Diameter. If you want to take off .064 you dial it in and not divide .064 /2 = .032 and then dial this in. You dial in what you need. No calculations, Bingo you are done. Easy
> Hilmar



You might dial in like that on some lathes, and it's like that on one of the the lathes being discussed in this thread, but not the other one. 
I've worked with many different lathes, in a number of shops. If you do it the way you describe on most lathes, you'll be over cutting every time. A great deal of lathes show the movement of the cross slide on the dial, not the diameter you're cutting.

Far as machinist friendly goes, what, you like doing everything in multiples of four?


----------



## steamnut2010 (Aug 16, 2010)

"....what you like doing everything in multiples of four?"


No not really, no not really, no not really, no not really.

Sorry, I could not resist. Machinist humor.  : )


----------



## Deanofid (Aug 16, 2010)

Ha! I get it, and it didn't even take me very long!
 ;D


----------



## mklotz (Aug 17, 2010)

steamnut2010  said:
			
		

> Thanks Marv and Dean-
> 
> That does shed some light on the dial subject.
> I will have to get out the dial indicator and try some of the things you mention, comparing the dial indicator with the dial on the feeds.



In the interest of helping other novices who may read this thread some day, let me encourage you to report here what you did and what you discovered by doing it.


----------



## Deanofid (Aug 18, 2010)

EDIT: I don't know what happened to this thread, but the post that follows was made in comment to
the nine consecutive posts made by JorgensenSteam, trying to address a multitude of statements/comments/queries he had made in his nine posts.

Suddenly all those posts are gone? So, what follows doesn't make sense.
END EDIT


Did you have a question? I'm not sure..

You don't have to make a new post every two paragraphs. You're allowed to put your comments or
questions in one post.

About your calipers. I would not assume that a B&S, Starrett, and Mit are off because you get conflicting 
numbers from the Grizzly. 
Most likely the reason you got some of those weird numbers is you did not take up the backlash when doing the same settings twice.

The numbers being progressively worse as you crank one of the dials may be because Grizzly used
a metric screw and put imperial grads on the dial. The error in adds up.


----------



## steamnut2010 (Aug 18, 2010)

This book is in response to Mr. MKLOTZ as follows:

"In the interest of helping other novices who may read this thread some day, let me encourage you to report here what you did and what you discovered by doing it."

Mr. MKLOTZ is listed as Global Moderator, which gives me the impression he is sitting in a big chair at the helm of some giant something. Sure sounds important. 
If not, I just wasted a bunch of time. (Mr. MKLOTZ's picture is a bit iffy).

The lathe I am using is a 1994 Grizzly Model DF-1237G, with a 12" swing, and 37" center. I don't speak machineeze, so in laymans terms, to me, that means you can put a 12" diameter flywheel in the chuck without striking the ways, and the longest piece you can cut is about 36"-37".

Speaking of machineeze, I think DRO is digital readout (even I can figure that one out), but all the other acronyms that people use on this forum, nada.

The vets talk about their XYZ on the BCN over the YED HMXPT.
Scuse me? All Greek. CNC, yes I got that. Stop laughing people, there are a lot of newbies out here in home machine land.

Using a Starrett indicator in the combo toolholder (correct my lathe terms if needed, I am shaky on those), and when I turn the crossfeed dial 3 turns, it looks like I am off one increment, or off by 0.001" in three rotations. Crossfeed has 0-10 increments, with 10 turns = 1", each increment = 0.001".
Changing to a Mitutoyo (reads mm) to get more travel, with the same crossfeed dial, I got the following:

1 rotation of the crossfeed dial = 2.57mm (0.1011")
2 = 5.14mm (0.20236")
3 = 7.17mm (0.30354")
4 = 10.285mm (0.40492")
5 = 11.30mm (0.4448")

So maybe the lathe is off, or maybe the Mitutoyo is off.
Then I went to a digital caliper. 
The digital caliper is a 6", $24.00 job.
I clamped the end of one jaw in the toolholder, and opened the calipers fully, and then used a magnetic holder to push against the end of the caliper.
I then rotated the crossfeed dial until the digital caliper started to read, and then reset to zero, and set the crossfeed collar to zero.

I recorded values twice with this setup as follows:
Using digital caliper on crossfeed:

1 rotation of the crossfeed dial = 0.98" and 0.85" (two separate sets of readings)
2 = 0.1985" and 0.19"
3 = 0.2975" and 0.29"
4 = 0.3975" and 0.385"
5 = 0.497" and 0.485"
6 = 0.597" and 0.585"

Not sure of the accuracy of the digital caliper.
Then the same crossfeed setup with a Browne and Sharpe dial indicator:
(Two sets of readings)

1 rotation of the crossfeed dial = 0.9" and 0.94"
2 = 1.882" and 1.925"
3 = 2.883" and 2.925"
4 = 3.94" and 3.94"
5 = 4.855" and 4.92"
6 = 5.826" and 5.86"

Still not sure how accurate the Brown and Sharpe indicator is.
I then put a piece of steel shaft in the 3-jaw, and made an initial cut to make it exactly round while spinning.
I measured the shaft with both the digital calipers and two different micrometers.

The digital calipers measured 1.452" and the micrometers both measured 1.446".
Playing around with the digital calipers, I noticed that a reading taken at the very front of the caliper jaws is more accurate then towards the back of the jaws.
The front measurement was 1.445".

I made another light cut, and used the micrometers to measure the diameter of the shaft at 1.429". I then rotated the crossfeed dial 5 increments or 0.005", and made a cut. The piece measured 1.420" in diameter. 
Again, I rotated the crossfeed dial 5 increments or 0.005", and made a cut.
The piece measured 1.41".
So a change of 5 increments on the crossfeed dial or 0.005" reduced the diameter of the work by 0.01".
The dial on the carriage of the above Grizzly lathe reads 0-0.58", in increments of 0.004" for each increment.
Using the Brown and Sharpe dial indicator, the rotation of the carriage dial produced an identical movement of the carriage into the workpiece.
The problem with having a dial with 0.004" increments is that the increments are too coarse to be accurate.

0.004" is a lot of movement of the carriage relatively speaking.
But for the short travel of the Brown and Sharpe dial indicator, the carriage dial seemed to match well.
I looked around on the net (unfortunately I skipped through several sites without capturing the addresses), and one guy actually made dials for his lathe that were double in size, with twice the increments, thus doubling his accuracy.

The Grizzly I have could easily accomodate double-sized dials.
The carriage feed should definitely have been made double in size.

I will have to look at the numbers listed above again tomorrow in order to try and draw some valid conclusions.

For non-critical work, I use mechanical vernier calipers, and have jammed up one unit with small chips, making it unusable.
For critical work, I use the various sized micrometers, and use the expanding thingys (help me out here with the name) for measuring inside the bore.
The expanding thingy springs out, and you lock it, then put the micrometer on it.

One of the first things I learned, other than breaking every bit I used, is that if you need a part accurate, do not remove it from the lathe chuck before you make all of your cuts. Once you rotate a part in the lathe chuck, even with a dial indicator, you may never get it back exactly square in the chuck again.

I use the spacers (what are those little flat suckers called?) parallel sets maybe (I won't try to hide my ignorance because I am sure other newbies can identify with having to learn all the names of the equipment, and the vetrans like a good chuckle since they have forgotten they ever had to learn this stuff too) behind the piece to square it in the lathe chuck if I absolutely have to remove the piece from the lathe, but have no idea if this is the correct application for parallels or not.

If I had time and money, I would take some machining classes, but I have neither.
I am lucky to get an hour in late at night every so often after everyone (including the war department) goes to bed.
I generally read the Enco catalog to try and remember the names of all the gadgets.


----------



## Maryak (Aug 18, 2010)

Steamnut,

Thanks for all your time and effort. You now know that your cross slide dial is set for radius and a cut of 5 increments = 0.005" which in turn = .010 removed from the diameter. The number of increments in 1 complete turn on your dial will be equal to the pitch of the cross feed lead screw.

Hazarding a guess 1 turn is probably equal to 100 increments or 50 increments, so 1 turn = 100 x 0.001" or 50 x 0.001"

Hence the pitch of the screw is 0.1" or 0.05," (This is the normal way in which metric threads are described e.g. 15mm dia x 1.25 mm pitch).

If we divide 1/0.1 = 10 or 1/0.05 = 20 we have arrived at the number of threads per inch, (tpi). This is the normal way in which British and US threads are described e.g. 5/8" x 11 tpi.

I hope this help with the Machinese, (I love the term), and I hope I'm not trying to explain something you already know.

Best Regards
Bob


----------



## Dan Rowe (Aug 18, 2010)

Steamnut,

I have run quite a few different makes of lathe and all had dials. Each time you encounter a new machine you have to work out the cross feed as you did.

My problem is I tend to forget how my own machines work after a few weeks of not being in the shop. That gives me a lot of practice in working the issue out.

Yes acronyms can sometimes be confusing even to an experienced machinist. As we are all here to learn and help fellow model builders simply asking what the letters stand for is the way I handle the issue.

Dan


----------



## mklotz (Aug 18, 2010)

> Mr. MKLOTZ is listed as Global Moderator, which gives me the impression he is sitting in a big chair at the helm of some giant something. Sure sounds important.



LOL. First off, the last person who called me Mr. Klotz was my daughter's suitor. The name is Marv. We're very informal here.

I do sit in a big chair - mainly because I'm a big guy - but the only thing I'm at the helm of is a desk littered with the memorabilia of trips and the bits and pieces of too many hobbies.

Thanks for taking the time to write up what you learned.


----------



## steamnut2010 (Aug 18, 2010)

Thanks for the feedback Dean, Bob, Dan and Mr. Marv.
Hey, there is no way I am going to address a "Global Moderator" as anything other than Mr., (or maybe "your Excellency", or "your Eminence" or something like that).
I guess the one thing that jumps out of the above data is the fact that the micrometers seem to be the only instruments that are consistent.

For the sizes of the outsides of work pieces that don't end up actually working against other pieced, the dials and collars on the lathe are accurate enough, and I generally don't use a micrometer to check final size of non-critical surfaces, but maybe use the vernier calipers to get in the ballpark.

For two pieces that have to fit and work against each other, I start with the lathe dials and collars to get close to the final size, but oversized, and then take a few small cuts to slowly get to final size measured with the micrometer.

So far, I am using a single carbide tool bit (with the replaceable insert) for everything (have not mastered threading on a lathe yet). The boring bars I use have high speed tool steel bits, but I would like to upgrade to a carbide insert boring bar, but am not sure of what type of carbide boring bar would be best. The tool steel bits need to be sharpened frequently, and sharpening a tool bit with all of the correct relief angles is not something I care to do constantly, especially when carbide inserts are cheap and easy, and stay sharp for a long time (but not forever) even with the abuse they receive from a newby. I can tell when I need to rotate the carbide insert, because the cuts begin to get rough, and the lathe starts to "sing" or vibrate when cutting the work.

The tool steel bits to not tolerate being overheated at all, and once you melt the end of a tool steel bit, you can forget about getting a good cut. If you sharpen a tool steel bit without the correct relief angles, then the bit does not cut at all, so that can be a significant newbie problem (been there, done that).

The sound of the cut is pretty much everything. If the cut does not sound right, then it will not be right.
Bit chatter and singing (vibrations) is not a good thing at all, and generally if you have chatter or singing, you may want to stop and take a look at what you are doing. Too deep of a cut is always accompanied by lots of chatter and singing.
I have cracked a few carbide inserts doing dumb stuff, but the beauty of the carbide inserts is that you can rotate each one three times, so you have three errors per insert (EPI's as I like to call them in jargon land), and inserts are cheap.
I have used a few large and wide tool steel bits to make final large radius rounded corner cuts.

I use the cutoff bits with the back gear engaged (and the pin out or the lathe is locked up). I still get a lot of chatter even with an extremely slow hand-feed rate, and am looking at using a wide slitting saw to make piston ring grooves, or at least roughing them out, maybe on the mill.

Using only one carbide lathe bit does produce a slightly rough finish on turned material, and I am sure a somewhat more rounded end carbide bit, or maybe an angled carbide bit would give a better finish. As a newbie, the slightly rough finish is a fair tradeff since it allows me to get started cutting and learning without getting overwhelmed in information.

Another mistake I first made was hanging the bit too far out on the holder. That makes for a not so rigid bit that deflects and chatters, and gives a poor cut. I lost some bits to not having the toolholder central support screw tight enough, so the toolholder rotated the bit into the work, breaking the bit.

I also learned early on that you cannot get a decent cut hanging a workpiece out of the 3-jaw chuck 6 inches, and then cutting along its length without supporting the end of the work. Definitely does not work. I have learned to support the end of all work with the live center at all times unless the piece is very short. A non-supported piece will have a dimension that varies from the supported end to the non-supported end, since the piece flexes like a spring under the cutting force.

Getting a good lathe chuck grip on a piece is also critical, and early on, I had some pieces come out of the 3-jaw because I did not really have a good grip on the piece, or was gripping a little hub on a flywheel, and then cutting way out on the rim. What is not readily apparent to the newbie are the large forces that push on the lathe, workpiece, bit and toolholder. Without getting a feel for how much force you are applying, you end up with lots of problems and broken things. What they really need is a force indicator on the tool post holder, and probably another on the lathe bearings (force-O-meter). Then you could tell when you are getting ready to snap something off or melt a bit.

Again, all this seems like "well duuu" to the veterans, but it is just not obvious to us newbies. Most of the veterans are very understanding of the newbies, but a few are quite intolerant (not necessarily on this forum, but certainly at the big shows), and seem to have trouble rewinding their knowledge base back to the beginning, being patient, and accepting that newbies do some really stupid stuff (like I do all the time). 

But the reality is that you have to learn to crawl before you walk, and learn to walk before you run, etc. Without the newbies, there will be no future to this hobby, and today's newbie is tomorrow's potential master builder.


----------



## mklotz (Aug 18, 2010)

Steamnut,

Getting an accurate measurement with calipers requires the development of a bit of technique. The part being measured should be as close to the beam as possible. If it's near the tips of the jaws, it's easy to press a bit too hard and tilt the moving jaw and get an undersized reading.

The measuring faces of the jaws must be parallel to the work. It's very easy to cant the work slightly against the jaws and get an oversized reading.

With a micrometer, the parallelism of the jaws is guaranteed by the construction of the device. It's still possible to clamp them too loosely or tightly. One must develop a feel for the right amount of pressure. (Practice measuring something of known size, such as a plug gage or gage block.) Some mikes are equipped with clutches to normalize the applied pressure. We can discuss that further at a later time.

IMO, it's awkward as hell to measure anything on the lathe with calipers - a perfect invitation to bad measurements. Use the micrometer whenever you can.



> Most of the veterans are very understanding of the newbies, but a few are quite intolerant, and seem to have trouble rewinding their knowledge base back to the beginning, being patient, and accepting that newbies do some really stupid stuff (like I do all the time).



I have to take issue with this statement. I read nearly everything published on this forum and everyone seems to do everything they can to help novices. If the help you are receiving isn't exactly what you wanted or expected please remember that you're dealing with individuals who each have their own ways of expressing themselves. Don't confuse a communication disconnect with "intolerance". Also, recognize that, as a novice, you have a lot to learn, and all that material can't possibly be assembled into a single comprehensive post. Keep reading and picking up bits of knowledge, record them in your notebook, and soon most of this stuff will cohere into a solid grounding in the basics. When you have specific questions, ask them. History suggests you'll almost always get an answer.

OTOH, if you still feel that someone is mistreating you, PM me (or any other moderator) and I'll attempt to resolve the issue for you.

Please put your location in your profile. It helps when answering questions about sources of supply. Also, there may be someone near to you who may be willing to provide some face-to-face assistance.


----------



## steamnut2010 (Aug 18, 2010)

Marv-

I did add to that statement, since it was too broad.
I have received very good support on this board, and think very highly of the members and their adopting newbies and guiding them.
It is an excellent way to connect newbies with the experienced builders.

My thoughts about intolerance go back to days attending large engine shows, where you ask a dumb newbie question, and the guy all but rips your head off and hands it to you on a platter. More of a personality and old age problem for some of these guys, and luckily not one I have run across on this board, but for those who may not have been as tolerant as they could be in the past, this is an opportunity to help the newbies and get more enjoyment out of the hobby all at the same time.

A win-win situation for sure.

This board is definitely the best.
You have only to read all of the helpful posts to realize that.


----------



## steamnut2010 (Aug 18, 2010)

From my standpoint, I guess I sort of span both ends of the spectrum.
I am an older guy starting a new hobby, so I can relate to both the younger and older crowd.
I have the same questions as an 18 year old beginner would have.

I think there are others on this board who are in a similar situation, starting a new hobby late.

Does this board have a "Frequently Asked Questions" area, where some of the questions that get asked repeatedly by newbies could be published and sort of honed and refined by the experienced guys (and girls).
It would save having to repeat some of the answers with every new person, and would probably give more accurate answers that were developed as a general concensus among the experienced people.

You could just say "See FAQ #2" for a good answer.

I would keep it well organized, i.e. Frequent questions for beginner machinists, and mid-level machinists, for advanced machinists, so that you could start at the beginning and work up to the more complex questions without loosing the trees in the middle of the forest.

Maybe this board already has this somewhere?



I will start a list of questions that I have had to learn so far:

1. When do I use a carbide bit and when to I use a tool steel bit?
2. How critical is cutting speed when using carbide bits vs tool steel bits?
3. How do you remove a lathe chuck?
4. How to you change a milling bit in the milling machine?
5. How critical is it to level your lathe before you begin using it?
6. What are the easiest materials to build with, and the least expensive?
7. What is the definition of "machinability", and how important is that to material choice?
8. What are the dangers of trying to weld or silver solder a material that is not suitable for such an application?
9. Which materials need special attention if they are welded or silver soldered?
10. What are some critical safety areas with regards to home machining, such as dust, fumes, etc.?
11. What is the importance of a material safety sheet?
12. What are the minimum machines and tools I need to get started making simple engines?
13. What are some simple machining guildlines just to get started, without getting into the more complex procedures?
14. I just spent 8 hours working on a piece, and have now jammed it, and damaged it. How do I salvage the piece so I don't have to start all over again?
15. What materials lend themselves better to salvage if they are damaged, and why?
16. What do I do if I break off a small drill bit in an almost finished part?
17. How do I drill and tap holes, and where are some good tap/die/clearance drill charts?
18. Where can I find a standard fastener web page?
19. How do I measure a standard fastener as far as length, size, threads per inch, type, etc.?
20. Is there a standard fastener chart with pictures of each fastener type available?
21. Which type of fastener is approriate for which type of model application?
22. How important is the strength of the fastener, and how do I figure out the weak fasteners from the strong ones?
22. How do I find out standard materials sizes and shapes for brass, steel, aluminum, gray cast iron?
23. Where can I purchase inexpensive and very small quantities of brass, steel, aluminum and gray cast iron?
24. What do the spec numbers for the materials mean, for example "405 Stainless" (number made up)?
26. How do I now which spec number for which material is appropriate for a particular use, as far as strength, finish, machinability, weldability, etc.
27. Are there materials and/or fluxes that contain hazardous materials that I should be aware of?
28. Is there a standard "beginner" engine plan set/design on this site that can be a starting point for someone who has never built an engine?
29. My first engine has the kindergarten "broken crayon" look and feel. How do I make my second engine more refined in appearance and operation?
30. My first engine has a lot of parts that do not allign correctly, and parts that make noised when they rotate such as bearings. How do I tighten up the fit and alignment of the model?
32. What are basic operations that are normally completed in the milling machine, and why would a milling machine be beneficial in addition to a lathe?
33. What bits are normally used in a milling machine, and can the same bits be used in the lathe, or do I need a separate set of bits just for both the lathe and the milling machine?
34. Name 10 of the most important "do's and don'ts" for a person who has never used a machine tool.
35. Where can I purchase or how can I make those tiny little bolts you see on some models?
36. Is it easier/cheaper/better to purchase my materials at the local hardware store than to purchase them online?
37. Where are several good/inexpensive places to purchase bits and tools?
38. What are some quick pros and cons of building in metric vs using other standards?

Add your own newbie questions onto the end of this list.


----------



## mklotz (Aug 18, 2010)

I'm glad to hear that you're browsing the ENCO catalogue for tool names. Don't just look for names, however. When you see a tool unfamiliar to you, try to puzzle out its use. If ENCO is selling it, it must be useful to a bunch of people in the business, so it might be worth understanding what it does.

Of course, you won't be able to puzzle everything out on your own. Knowledge favors the prepared mind. Get an entry-level shop course textbook (community college bookstore or used from a library book sale) and browse it. Concentrate on techniques and how the tools are employed. It will probably be written with an industrial slant so you'll have to imagine how to adapt what you read to the smaller scale at which we work.

Get a copy of _How to Run a Lathe_ by the South Bend Lathe Co. (on the web or via a library book sale) and read it for more detailed lathe-specific techniques.

And, naturally, read this forum. There are excellent build threads that will walk you through all the minutiae of getting a project finished. There are also plenty of discussions on the use of tools, tool building, safety and other ancillary engine building concerns. Study the safety stuff first. Many of the things that can bite you in a machine shop aren't instantly obvious.

Certainly the best bet would be to take a metalworking course at a local CC. It sounds like you may not have time for that, though. That's OK. Many of us, myself included, are self-taught with no work experience in the field and no classroom instruction. It can be done but it requires, like any learning task, patience and persistence.


----------



## Lakc (Aug 18, 2010)

steamnut2010  said:
			
		

> For critical work, I use the various sized micrometers, and use the expanding thingys (help me out here with the name) for measuring inside the bore.
> The expanding thingy springs out, and you lock it, then put the micrometer on it.



Im gonna take a wild guess here but since the expanding thingy "locks" then its likely what I call a telescoping gauge, or T-gauge for short. ;D


----------



## steamnut2010 (Aug 18, 2010)

Bingo, telescoping gauge, that is it.

Thanks Jeff

This site needs a dictionary of commonly used machining terms/devices/photos.
That would really help the new guys.


----------



## Blogwitch (Aug 18, 2010)

Steamnut,

I have sent you a PM, please read and reply.

Bogs


----------



## Lakc (Aug 19, 2010)

steamnut2010  said:
			
		

> Bingo, telescoping gauge, that is it.
> 
> Thanks Jeff
> 
> ...


Your welcome.

The web is full of that stuff, google is your friend, wikipedia is a guide. 

 Measuring is usually a different skillset from machining, although they go hand in hand. I have had no formal machining training but did have measuring training in auto mechanics trade school.

 I learned three very valuable lessons with one t-guage demonstration. The instructor showed us how to use a t-guage to measure a cylinder bore on an american v8 engine. Then he stuck the gauge in the bore parallel to the crankshaft centerline, used the heel of his hands to squeeze the bore on the opposite sides as the guage, and the gauge fell out. This guy wasnt 55kg soaking wet, so he was a pretty short skinny guy, and about 80 years old. 
 The lessons, metal moves quite easily in thousandth's of inches no matter how strong it looks; dont deform the part your measuring or the tool your measuring it with; sometimes you need the part deformed in place and assembled to get the true measurement you need.


----------

