# Anyone Use This Bit Centering / Aligment Gadget?



## gapi (Aug 16, 2015)

What do you guys think of this?


----------



## RJSakowski (Aug 16, 2015)

There is no reason it shouldn't work.  The sensitivity will be determined by the separation between the vee and the notch and the sensitivity of the bubble.  Most level vials are on the order of 1/16" per foot for a noticeable movement of the bubble.  For a separation of 2", this would be on the order of .01" difference in height for a sensitivity.  This of course assumes a level lathe. You would best adjust  the height by another method and  use that setting to "calibrate" your height adjustment tool.

Bob


----------



## Ed ke6bnl (Aug 16, 2015)

like Bob says the lathe need to me level for this to work as I see it.


----------



## Karl_T (Aug 16, 2015)

I'm sure it would work. But its a complex solution to a simple problem, IMHO.

I'll continue to just use my steel rule pinched against the stock to determine height. or just observe the tool right as it reaches zero on facing. Or just measure the height above the compound surface with my caliper. bet there's a couple more methods I'm not thinking of.

Karl


----------



## A618fan2 (Aug 16, 2015)

I've thought about one of those but found that a small tool mark on the tail stock spindle at the exact center height works beautifully.


----------



## Chipper5783 (Aug 16, 2015)

I have one of those little centering levels.  The only time I use it is when I need a small little level (not lathe tool set up).  To center lathe tools, I use the tailstock center, the small ruler, a height gauge or a small gauge (depends on the set up).


----------



## gapi (Aug 17, 2015)

Thanks, I think I'll get one just to see how it reads compared to the other ways. The Lathe is level. Curiosity.


----------



## canerodscom (Aug 17, 2015)

I have and use one to get my tools close to center.  Observing while facing is certainly more accurate.  And btw, as pictured the level will not read accurately.  The very edge of the tool nearest the operator needs to be the only part touching the tool bit.  And it needs to touch only the very cutting edge of the tool bit.

Harry


----------



## Charles Spencer (Aug 17, 2015)

I have one and it works OK for me.  And you do have to make sure that only the flat part of the cutout rests on the tip of the tool.


----------



## Firestopper (Aug 17, 2015)

[QUOTE="Karl_T, 

I'll continue to just use my steel rule pinched against the stock to determine height. or just observe the tool right as it reaches zero on facing. Or just measure the height above the compound surface with my caliper. bet there's a couple more methods I'm not thinking of.

Karl[/QUOTE]
^^^^^ This is how I learned to center back in H.S.  MS class back in the late 70's. Been serving me well ever since.


----------



## chips&more (Aug 17, 2015)

I would save your money. It’s just another toy. I have been eye balling the tool height for 50 years and NEVER had a problem. When I face, I do take the time to totally remove that tit…Dave.


----------



## Bill Gruby (Aug 17, 2015)

The lathe does not need to be level for this tool to work. It does not need it. The vial level is only to let you know when you have hit dead center between the cutter and the work piece. It is not used as a level per-say. It just lets you know when you are straight.

 "Billy G"


----------



## george wilson (Aug 17, 2015)

The thin steel rule is quite enough for getting a bit on center.


----------



## RJSakowski (Aug 17, 2015)

Bill Gruby said:


> The lathe does not need to be level for this tool to work. It does not need it. The vial level is only to let you know when you have hit dead center between the cutter and the work piece. It is not used as a level per-say. It just lets you know when you are straight.
> 
> "Billy G"


The level vial is comparing to an earth reference so if the lathe is tilted front to back, the vial will not center the bit ion the spindle axis.  If you have leveled your lathe then fine, if not, I would calibrate the tool by checking a known good setup.  (Actually, I would check it against a known good setup anyway because there is no guarantee that the tool is accurate out of the box)

Bob


----------



## Bill Gruby (Aug 17, 2015)

It is not comparing an earth reference or any reference to the lathe bed.. It is just making sure the two points are on the same plane.  Ask the manufacturer he will agree with me. I have used one of these on both level and unlevel lathes. The results are the same. The tool is on center every time.

"Billy G"


----------



## chips&more (Aug 17, 2015)

In the picture above it is actually showing the tool/thing being used incorrectly! The top or corner of the carbide insert is resting on that angled side. The little flat ledge on the tool/thing should be resting on the top of the insert. And it’s not that big a deal, but every time you go and use this thing, you have to crank the cross slide out and then back in. I see unnecessary wear on the feed screw, nut and gibb…Dave.


----------



## RJSakowski (Aug 17, 2015)

Bill Gruby said:


> The lathe does not need to be level for this tool to work. It does not need it. The vial level is only to let you know when you have hit dead center between the cutter and the work piece. It is not used as a level per-say. It just lets you know when you are straight.
> 
> "Billy G"


How would you use it on a ship then?


----------



## Bill Gruby (Aug 17, 2015)

Let's just agree to disagree. How long have you owned and used one of these? I have had mine for 15 years. It's not a new invention. I won't discuss this any further. To the OP, my apologies for this disruption.

 "Billy G"


----------



## chips&more (Aug 17, 2015)

RJSakowski said:


> How would you use it on a ship then?


You would need to find a ship that is perpendicular to gravity .


----------



## george wilson (Aug 17, 2015)

Use of the steel rule works in any situation. Just visually make sure the steel rule is vertical to the bed of the lathe.Why spend money when you don't need to?


----------



## The Liberal Arts Garage (Aug 17, 2015)

Need I apologise If I bought it just because it'cute?..........BLJHB


----------



## stupoty (Aug 17, 2015)

george wilson said:


> Use of the steel rule works in any situation. Just visually make sure the steel rule is vertical to the bed of the lathe.Why spend money when you don't need to?



I use some shim stock thats just thick enough to be rigid, mainly because i kept dropping the rullers in the swarf 

Stuart


----------



## Andre (Aug 17, 2015)

I agree with Bill, however if the lathe is tilted off the level plane (say 5 degrees) and you set it level maintaining tool parallelism with the top of the compound (Think: QCTP.) the rake and relief angles of the tool will be minutely affected. If you use a lantern toolpost, well then it's messed up anyways.

You will never, ever notice the difference between a theoretically perfectly level lathe and one off a little. A lathe off one degree is a rarity. For all intensive purposes it doesn't matter if your lathe is level.


----------



## mikey (Aug 17, 2015)

Bill Gruby said:


> The lathe does not need to be level for this tool to work. It does not need it. The vial level is only to let you know when you have hit dead center between the cutter and the work piece. It is not used as a level per-say. It just lets you know when you are straight.
> 
> "Billy G"



I don't own one but I have tried one that belonged to a friend. It works exactly as Bill says.


----------



## RJSakowski (Aug 18, 2015)

If you read, what I had posted, I said in post #2


RJSakowski said:


> There is no reason it shouldn't work.  ..... This of course assumes a level lathe. You would best adjust  the height by another method and  use that setting to "calibrate" your height adjustment tool.


.  In post #14, I said


RJSakowski said:


> ..... If you have leveled your lathe then fine, if not, I would calibrate the tool by checking a known good setup.  (Actually, I would check it against a known good setup anyway because there is no guarantee that the tool is accurate out of the box)


.

While I was not able to find the operating instructions for this product, I did find an operating manual for a product using the same principle from www.edgetechnologyproducts.com (http://store-1wa94vq6.mybigcommerce...ual/pro_lathe_gage/pro_lathe_gage_manual.html)

_"Level Calibration
• For optimum results this unit should be calibrated to compensate for machines that have not been accurately leveled. 
 • Position the base of the gage on a flat surface of the lathe such as the compound or cross slide. The unit should be perpendicular to the axis of spindle rotation as shown.

 • After loosening the adjustment screw the level housing can be rotated until the bubble is centered in the vial."_

An uncalibrated tool will give you consistent tool height settings for your lathe and, depending on how close to level it is , they may very well be within the range of uncertainties.  All I said, was to verify it against a  known good setup. 

The vertical steel rule method used by many will shift the tool height up or down by .01" on a half inch diameter workpiece with an error in estimating the angle of a little over 2 deg.  Visually sighting against a center can present errors of .01" without too much effort. Turning to a zero diameter tit on the face of a piece of work is probably the most accurate but again, I am not sure you can do much better than .01".

I have used all three of those methods for many years and in reality, setting a tool height to better than .01" is probably not at all necessary.  So yes, the tool will work and I would use it myself.  But, for my own piece of mind, I would verify the calibration.

Bob


----------



## Bill Gruby (Aug 18, 2015)

Thank you.

 "Billy G"


----------



## chips&more (Aug 18, 2015)

The picture in this thread is from a fleabay sellers listing. And the irony is the seller is showing the thing being used incorrectly! If you really want one of these things. I would do an eBay search to get some ideas and then make one for yourself. I see one there that has an adjustable vial. Makes it kinda nice if your lathe is not level. You can calibrate that one to your lathe as it stands. And you thought you had the day off. Now you have a project…Dave.


----------



## coolidge (Aug 18, 2015)

Gunrunner you need to order a set of these for the Z axis hand crank. Bill did you just spit coffee on your monitor? :rofl:

View attachment 253356


----------



## RJSakowski (Aug 18, 2015)

coolidge said:


> Here's a centering tool someone on the forum invented and I copied their idea. This has worked out awesome. I calculated the center height for my lathe then turned this simple tool, easy to see even for my old worn out eyes. I set all my tool heights with this and they have been spot on ever since.


Tom Lipton from OxTool uses something similar.  A further improvement would be to replace the upper cylinder with a dial indicator to read the offset amount.  Even easier on the eyes.  I have an old Ames dial indicator earmarked for that purpose.

Bob


----------



## The Liberal Arts Garage (Aug 18, 2015)

RJSakowski said:


> If you read, what I had posted, I said in post #2
> .  In post #14, I said
> .
> 
> ...


           Bob, level your lathe standing in as your conscience,..BLJHB


----------



## ronzo (Aug 18, 2015)

Gee ! Ive been using lathes for 65 yrs.  I never knew I needed one of them there whiz bang gizmos.


Sent from my iPad using Tapatalk


----------



## Bill Gruby (Aug 18, 2015)

You don't. I got mine for free from G.M. or I wouldn't have one either.

 "Billy G"


----------



## george wilson (Aug 18, 2015)

To tell the truth,unless I am turning something critical like a taper,where the tool must be centered or it cuts a concave taper,I just set the tool by eye.


----------



## PatMiles (Aug 18, 2015)

I use a steel rule as the folks above do. After that I will take a trial face cut. If the cut cleans the face completely you are there. If the face cut leaves a pointed tit (>) the tool is too high and needs to be lowered. If it leaves a square tit (-) the tool is too low and needs to be raised. Once this is done you are usually good to go for a long time as long as the cutter stays in the tool holder and not changed out. Takes about 5-10 minutes.

Save your money and don't buy the gimic tool.


----------



## RJSakowski (Aug 23, 2015)

If anyone is thinking about buying one of these, they are currently being sold for $10.95 with free shipping on eBay. 

http://www.ebay.com/itm/Lathe-Gage-...id=100033&rk=3&rkt=4&mehot=pp&sd=321131250382

Bob



gapi said:


> What do you guys think of this?


----------



## Ulma Doctor (Aug 23, 2015)

i have one, got it from the ebay store bob suggested above a couple years ago!


----------



## RJSakowski (Aug 23, 2015)

Mike, I just ordered one myself.  For little more than the cost of lunch at Mc D's, it will save me the hassle of making my own.

Bob


----------



## Bill C. (Aug 23, 2015)

Karl_T said:


> I'm sure it would work. But its a complex solution to a simple problem, IMHO.
> 
> I'll continue to just use my steel rule pinched against the stock to determine height. or just observe the tool right as it reaches zero on facing. Or just measure the height above the compound surface with my caliper. bet there's a couple more methods I'm not thinking of.
> 
> Karl



That was the way I was taught. I would pinch my scale then walk back to tailstock to see if the scale was straight up or tilted.


----------



## gapi (Aug 23, 2015)

Thanks Guys, I always go for the tit too. I think I'll get one anyways to dazzle newbs with and to check against my method for curiosity.


----------



## aametalmaster (Aug 23, 2015)

Karl_T said:


> I'm sure it would work. But its a complex solution to a simple problem, IMHO.
> 
> I'll continue to just use my steel rule pinched against the stock to determine height. or just observe the tool right as it reaches zero on facing. Or just measure the height above the compound surface with my caliper. bet there's a couple more methods I'm not thinking of.
> 
> Karl


Like this? This is how I was taught 40 years ago. Top leaning right, lower the tool. Top leaning left raise the tool. And great for finding center...Bob


----------



## gapi (Aug 23, 2015)

This is the only can-o-worms I ever opened that I liked.


----------



## Wheresmywrench? (Aug 23, 2015)

Here's another one.


----------



## RJSakowski (Aug 23, 2015)

Wheresmywrench? said:


> Here's another one.


Saw that one too.  It looks well made and the cost is little more than the first.  A little more complicated to use in that you would have to mount a chuck in the headstock or tailstock.


----------



## Wheresmywrench? (Aug 25, 2015)

_I just might get one. My old eyes are having a problem finding center._


----------



## RJSakowski (Aug 30, 2015)

gapi said:


> What do you guys think of this?


An update:  

I purchased one for myself and it arrived yesterday so I though I would give an evaluation.  I got mine through eBay for $10.95, shipping included.  

The level vial is sensitive enough to detect a 1.5 mil feeler gauge inserted between the tool bit and the gage.  The sensitivity is determined by the  distance between the contact point on the upper surface of the tool and the center of the round so it will be less sensitive with a larger diameter cylinder.  I used a 3/4" pin for the evaluation but also checked performance with  .170" and  2.000" rounds. 

Although the gage's function is to set tool height to be on line with the spindle axis, it is also possible to accurately set the tool height above or below the axis.  To set below the axis, a feeler gauge or pin gage equal to the amount of drop is placed between the tool and the gage's measuring surface.  To set above, if some some reason, you wish to do so, place a feeler gage equal to 1.414 times the amount of rise desired between bottom edge of the 90 deg. vee, thereby lifting the center line of the gage by the amount of rise.

The lower flat surface is parallel to the level vial, making it a convenient way to check the level of your cross slide ways.  If the cross slide ways reads off level, you can still use the gage by adjusting your tool height to read the same as it does on the ways.

In conclusion, this tool is the most accurate means of measuring lathe tool height that I have used.  Additionally, for on center alignment, it is on a par with the vertical rule method for ease of use.  Its use requires a cylindrical surface between .2 and 2" in diameter concentric with the spindle axis but this is not a particular handicap with lathe work.  Should one be running a facing operation and not have a cylindrical surface, a pin can be inserted in the tailstock chuck and the measurement made there.

Bob


----------



## Wheresmywrench? (Aug 30, 2015)

I have this one. I like it because you can zero it by setting it on the tool post holder and adjusting the bubble to the level position to allow for the possibility that lathe may be slightly off level. It's a bit of a PITA but once done you know that your tool post and the center of your work piece are on the same horizontal plain.


----------

