How to interpret the values of a chamfer and a thread in a blueprint
I am trying to CAD up the bar that is represented in the blueprint. I am fairly new to reading blueprints though and I have two questions.
1) Seeing in the attached chamfer picture (that someone else has made over the same blueprint) he/she is using a chamfer with some values (seen in the attached picture). I am just wondering where he/she gets the values from - 45 deg and 0.9mm in distance?
2) For the threaded part I am just wondering where I can look up the values of the thread - M10*1.5 - 6H (e.g. pitch and so on).
Reading the drawings is pretty basic. You should get used to them after few practical machining work.
For chamfer dimension, there is no information about it in images attached. Maybe it is about deburring sharp edges as 0.90mm is pretty small or maybe it was mentioned somewhere else in project drawing to be assumed in all drawings.
The threaded holes dimensions can be looked into charts. For M10x1.50, I.D. of the threaded hole will be 8.50mm (10.00-1.50=8.50). Also the pitch is 1.50mm.
I am attaching table here.
6H is the tolerance class of the thread. The exact values can be found in the thread specification.
You could compare this like accuracyclass "medium" in your table for deviations of dimensions
The chamfer is not given in the drawing, but it is a common practice to camfer the end of a threaded hole for 2 reasons
1. a decreased possibility of getting hurt due to sharp edges - especially at the end of the turn of the thread
2. its easier to fit in the counterpart (comparable to a cone)
For example take a normal hexagon nut and look at the end of the thread.
The size is defined the thread - the dimension should be a little larger than the outside diameter of the thread.
This explains also the value "0.974..." of the camfer because it is defined at the nominal core bore of the thread