Calibrating Plain Tapered Bores at the Small End Diameter

[kixxy]

Hello first of i hope i'm posting in the correct forum. (Sorry if i'm not)

An issue i have been having at work is calibrating Plain Tapered bores @ the small end diameter. Our company manufactures Plain taperd bore gauges and the Work shop and i measure them. I take my reading from the Large end diameter with comparison to a calibrated plug gauge.

So now i have the measured large end diameter of the plain ring bore i also take the overall length of the plain bore gauge.

The problem/dispute i have

I was told the maths is simple all i have to do is:

Divide the overall length by the rate of taper then take away that figure of the measured large end diameter.

The question is what if the rate of taper/angle is incorrect ?
The procudure i have been given assumes that the Rate of taper/angle is correct.

I Hope that this isn't confusing as my grammer isn't that great. I was just hoping that any one with experiance with plain tapered bores could give me and insight/ infomation in this matter.

 

[George Weiss]

hello new post person,
Using a plug gage set again at the small end is the better method for sure.
Is there a reason why you would not do this? Restrictions/limited access?
The required accuracy likely would exclude your described method. This would have to be evaluated and checked.
Using a smaller plug-gage seems so much simpler.
Your idea/method, in theory works.
The accuracy achieved and needed is for you to determine and conclude if acceptable.
The added error of depth/length, taper-angle. and variations from part-to-part add up!
Just doing a little de-burring of small end could throw off value.
Do remember it is the bosses right to be wrong.
I just concluded you are making the gage with outer dimentions, right?

 

[Coury Ferguson]

Hello first of i hope i'm posting in the correct forum. (Sorry if i'm not)

An issue i have been having at work is calibrating Plain Tapered bores @ the small end diameter. Our company manufactures Plain taperd bore gauges and the Work shop and i measure them. I take my reading from the Large end diameter with comparison to a calibrated plug gauge.

So now i have the measured large end diameter of the plain ring bore i also take the overall length of the plain bore gauge.

The problem/dispute i have

I was told the maths is simple all i have to do is:

Divide the overall length by the rate of taper then take away that figure of the measured large end diameter.

The question is what if the rate of taper/angle is incorrect ?
The procudure i have been given assumes that the Rate of taper/angle is correct.

I Hope that this isn't confusing as my grammer isn't that great. I was just hoping that any one with experiance with plain tapered bores could give me and insight/ infomation in this matter.

Welcome. Yes you did post this in the right forum. If it would have been placed wrong, we would have moved it so that you would get better responses to your question. Keep the questions coming, there are a lot of people that are members of the Cove, that will help.

 

[kixxy]

Thank You for your replys. Infomation has been noted.
One last quick question.

If the Pencil/Micrometer Blue Test was proformed but results found were that there was no contact on parts/all of the Tapered Bore.Then how would you include the findings into your measured results ?
That would be using a calibrated plug gauge with the correct taper and large end/small end diameter which should mate to the Tapered Bore Gauge.

 

[George Weiss]

Some gages are built as spec. +/-, some spec. + only, and some Spec. – only.
In your case, you likely have a diameter large and small, which is spec. + only.
Assuming small and large opening diameters are >=spec, then:
Then the linearity of the taper from large to small opening would be small enough to show no high points.
You may or may not spec actual diameter between both ends/opening, except that it does not reach your blue mark minimum.
This would show that all diameter points between small and large openings is >= relative diameter spec. minimum.
This test is a pass/fail feature is >=relative dia. Spec.
or
test item: >=relative dia. = pass or fail

 

[sitapaty]

Hello first of i hope i'm posting in the correct forum. (Sorry if i'm not)

An issue i have been having at work is calibrating Plain Tapered bores @ the small end diameter. Our company manufactures Plain taperd bore gauges and the Work shop and i measure them. I take my reading from the Large end diameter with comparison to a calibrated plug gauge.

So now i have the measured large end diameter of the plain ring bore i also take the overall length of the plain bore gauge.

The problem/dispute i have

I was told the maths is simple all i have to do is:

Divide the overall length by the rate of taper then take away that figure of the measured large end diameter.

The question is what if the rate of taper/angle is incorrect ?
The procudure i have been given assumes that the Rate of taper/angle is correct.

I Hope that this isn't confusing as my grammer isn't that great. I was just hoping that any one with experiance with plain tapered bores could give me and insight/ infomation in this matter.

The product you are referring to, is a taper ring gage which falls under high precision category.The method you are employing is gaging and it cannot give you the exact size of your taper bores.You have to use measuring balls and gage blocks to measure a taper ring gage.Or you have to use a taper measuring machine which uses spherical stylus.Gages are measured in air conditioned room.
Sitapaty.

 

[kixxy]

Thank You very much. I understand now. This should clear alot of stuff up in the Lab at work.

 

[George Weiss]

I am not the one to drag people off to other forums but also would suggest, just for the heck a calibration forum site. http://www.pmelforum.com/
The people there are VERY in touch with calibrations specifically. There are people there who live and breath dimensional calibrations. Where-as the calibration aspect of quality is just a subclause. They would likely pass to you complete procedures and have a dozen ways to do anything. Just a closing comment. I might be dragged off and avatared for this comment.