Concerning tolerance for linear masurement
Concerning tolerance for linear masurement
(OP)
Hi,
The question is presented in the picture below
Kindly
Paul
The question is presented in the picture below
Kindly
Paul
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Concerning tolerance for linear masurement
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RE: Concerning tolerance for linear masurement
You have not specified a standard.
ASME Y14.5 specifies that any measurement between the two surfaces lies between the specified tolerances. Any geometry that allows that, is legal. Watch out for the angle tolerances on your drawing title block. According to ASME Y14.5, this is what controls the perpendularity of your sides.
I understand ISO is different.
RE: Concerning tolerance for linear masurement
RE: Concerning tolerance for linear masurement
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The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
RE: Concerning tolerance for linear masurement
btrueblood
My intepretation of what you said when you mentioned calipers is that you imply that it is govern by cross sections because the caliper does not cover the entire surface?
You used the word points, which is even more limiting then cross sections.
RE: Concerning tolerance for linear masurement
The answer is "Yes"
RE: Concerning tolerance for linear masurement
Frank
RE: Concerning tolerance for linear masurement
You can add Envelope requirement to your dimension:
20+/-0.5(E) (It's "E" in circle)
Then it will include flatness.
RE: Concerning tolerance for linear masurement
Do anyone know in what section in ISO 8015 i can read about this?
RE: Concerning tolerance for linear masurement
RE: Concerning tolerance for linear masurement
However there is newest version of this document issued this year and the independency principle is described in clause 5.5.
RE: Concerning tolerance for linear masurement
You may be out of luck if your print invokes ISO 2768-2.
Also, ISO 1101 (if specified)automatically invokes 2768.
Boy, I love where this is heading!
RE: Concerning tolerance for linear masurement
So ISO 2768-2 is a subsection to ISO 8015 or how does that work?
RE: Concerning tolerance for linear masurement
There is a pair of standards, ISO2768-1 dealing with untoleranced dimensions, and 2768-02 dealing with unspecified geometrical tolerances.
They are causing some controversy and are not universally loved on this forum.
You can take a quick look at this picture:
http://www
It shows "invisible" GD&T implied by referencing 2768.
RE: Concerning tolerance for linear masurement
It means that if you refer to 2768-2 on a drawing the flatness is limited even that nothing else beside single dimension is shown on a print like in your example. According to the standard the intent of this is practice "to simplify drawing indication"...
Another important thing which is very often overlooked is that ISO 2768 (parts 1 & 2) are dedicated for parts "that are produced by metal removal or parts that are formed from sheet metal". This means that if your part is for instance a plastic plate formed in an injection molding process, refering to ISO 2768 is not a best choice.
RE: Concerning tolerance for linear masurement
ISO 2768-2 will specify default controls for things like flatness, if it is being invoked on the drawing properly (say"-mK", or such)?
Frank
RE: Concerning tolerance for linear masurement
RE: Concerning tolerance for linear masurement
Quote:
"In any event, general geometrical tolerances in accordance with this part of ISO 2768 should be used when the fundamental tolerancinf principle in accordance with ISO 8015 is used and indicated in the drawing"
RE: Concerning tolerance for linear masurement
RE: Concerning tolerance for linear masurement
if angle "d" was defined which shortest side will be use A or B?
RE: Concerning tolerance for linear masurement
We use A, but we choose between A and C
RE: Concerning tolerance for linear masurement
CH,
I noticed you seem to have an interest in this subject before, Do you use the ISO standard alot?
Frank
RE: Concerning tolerance for linear masurement
To Frank:
Not much, but I have big interest in everything "general", "implied", "customary" for practical reasons; also our company has European partner, so natural interest to how much info is actually hidden in their drawings
RE: Concerning tolerance for linear masurement
After i have been looking in some drawings to diffrent customers i do not see ISO 8015 anywhere. What i see is
ISO 13920
ISO 1302
Kindly
Paul
RE: Concerning tolerance for linear masurement
Frank
RE: Concerning tolerance for linear masurement
RE: Concerning tolerance for linear masurement
I just want to learn, but to learn i need a better answer then
this is "window dressing" haha. A natural follow up question to your statement would be:
What is the true function to datum reference framework in relationship to what i showed you?
RE: Concerning tolerance for linear masurement
John-Paul Belanger
Certified Sr. GD&T Professional
Geometric Learning Systems
RE: Concerning tolerance for linear masurement
I have proposed that the primary datum alignment would use one of the large faces, based solely on how I perceive this part will install. I hope you better understand how the part actually installs. If this is in fact a part that mounts primarily on the datum B surface then the first example is in the right direction and I am just wrong! However if one of the larger faces is how the part actually mounts you have not expressed that and so neither example really describes the functional assembly condition. Both are then just sketches to: "make a part that look something like this".
Frank
RE: Concerning tolerance for linear masurement
Who I made it in the first picture is absurd because it would mean that you would lock it by A "FIRST" then by B the outer side; which would cause problems with stability; you need to lock it by the larger side to create stability.
RE: Concerning tolerance for linear masurement
About your second picture:
ISO 2768 does not apply to location of Features of Size, they are very clear about it; so you are always better off specifying "proper" location with datum framework.