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dimensioning to T.I.P.

  • Thread starter Thread starter lindi
  • Start date Start date
L

lindi

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Please advise on procedure to dimension to theoretical intersection points.


Some features are: angled sides, radii, and centerpoints. (WC3)


Thank you, Lchoi
 
When you insert dimension, the popup menu gives you the option of Intersect. Select that and then pick the two edges that define the intersection point (hold CTRL key to select both edges at the same time). If the other end of your dimension is also an Intersect, then repeat, otherwise, you'll have to select "On Entity" again which is the default setting.


<tg>
 
Does anyone know of a standard that defines the TLA (Three Letter Acronym) for dimensioning to a sharp point? ISO, ANSI, etc?

I've seen TSC (To Sharp Corner or Theoretical Sharp Corner), TSP (To Sharp Point) and now TIP. I'd like to know which, if any, is covered by some national or international standard.
 
David, one more TLA I have seen is POI (point of intersection).
 
I do not know about the acronyms. I generally give a
suffix of REF (Reference) for the dimension since it
cannot be measured. Instead Dimensions Over Pins are
generally resorted to. e.g. Dovetail ways.
 
not quite a TLA but I have always used INT and have never been questioned about it.
 
I have used TI (theoretical intersection). Even if the dimension is not checked it has value for those still plugging g-code without CAM.

Chris
 
There are cases where it can be measured with an optical comparator.
 
ASME Y14.38 gives abbreviations for use on drawings. TSC, TSP, and TIP may not be the abbreviations to use. From the standards standpoint the notes would be THEOR SHARP COR or TO SHARP COR, THEOR SHARP PT, and THEOR PI. Abbreviations you choose may also conflict with the standard. For instance TIP from the standard is the abbreviation for turbine inlet pressure.
 
ASME needs to get with the TLA program. THEOR SHARP COR is much to long.
 
I usually avoid dimensioning to a theoretical point, or hidden features.


On the rare occation, I would supress the round in the model, place my dimension on the drawing, then resume the rounds in the model.


Regarding dr_gallup's comment about optical comparator: co-ordinate measuring machines (CMM) are also excellent formeasuring (calculating) theo points in space. Sometimes that is all you get to measure, a point in space.
 

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