topic Re: Separate in AutoCAD Mechanical Forum

Separate

Anonymous — Fri, 19 Feb 2016 15:17:51 GMT

I used UNION command to union A and B. Now I want to separate it, how it is possible. I don’t want to use EXPLOADE command because it can make every individual part in A and B separate. Screenshot and Drawing is attached.

Re: Separate

Anonymous — Fri, 19 Feb 2016 17:52:11 GMT

I have solved this problem. Please ignore this.

Re: Separate

JDMather — Fri, 19 Feb 2016 19:00:59 GMT

The threads in your fastners (hex head screws and nuts) are not modeled correctly.

Re: Separate

Anonymous — Fri, 19 Feb 2016 19:34:34 GMT

Can you tell me please the error?

Re: Separate

JDMather — Fri, 19 Feb 2016 20:40:32 GMT

Have you ever held fasteners such as these in your hand?

If so, you should be able to easily see how they don't match real world parts. Not even close!

Thread not modeled correctly in the nut. (see red)

Thread not terminated correctly on the cylinder and pitch incorrect (should be same distance root-to-root as crest-to-crest).

Re: Separate

Anonymous — Fri, 19 Feb 2016 21:14:28 GMT

I couldn’t understand your explanation. I attach Fastener specification given in tutorial.

Re: Separate

JDMather — Fri, 19 Feb 2016 22:41:55 GMT

1. The "tutorial" drawing is wrong.

2. You part does not match the incorrect tutorial drawing. Not even close. It should be visually obvious.

Re: Separate

Anonymous — Fri, 19 Feb 2016 23:52:18 GMT

Please take a trouble to produce a correct tutorial drawing.

Re: Separate

JDMather — Sun, 21 Feb 2016 15:41:27 GMT

@Anonymous wrote:
Please take a trouble to produce a correct tutorial drawing.

I can't help but wonder, "Where is your instructor?"

Re: Separate

Anonymous — Sun, 21 Feb 2016 16:17:09 GMT

If you can give me a correct drawing then only I can show to my instructor and pin point the error in her drawing.

Re: Separate

JDMather — Sun, 21 Feb 2016 19:50:18 GMT

There is not a thread size .5-10 UNC , it should be .5-13 UNC (Pitch =1/13=.077) and the tap drill sze (minor diameter) is .417 not .375

But the error on the drawing does not solve the problem that your model does not match the drawing.

Your threads simply won't work. The parts will not go together.

Re: Separate

Anonymous — Tue, 23 Feb 2016 03:41:20 GMT

My instructor accept the error in her drawing. Thank you for pinpointing me the error.

Re: Separate

Anonymous — Tue, 23 Feb 2016 11:22:27 GMT

Thank you for your tutorial as well.

Re: Separate

Anonymous — Tue, 23 Feb 2016 17:27:55 GMT

Can you tell me please how did you find out nut and bolt are not modeled correctly?

Re: Separate

JDMather — Tue, 23 Feb 2016 17:32:49 GMT

It is so obvious I don't know how anybody could miss the errors.

Go to the hardware store and purchase a nut and bolt (larger is better).

Now go back to your computer and compare the nut and bolt that you are holding in your hand to the image that I attached is post #5. See any obvious differences? (Tip: Look in the red areas.)

Re: Separate

Anonymous — Tue, 23 Feb 2016 18:28:28 GMT

Please see whether dimesions are correct now.

Re: Separate

dgorsman — Wed, 24 Feb 2016 16:20:21 GMT

As a counterpoint to JDMather - AutoCAD and verticals aren't as good at modeling complex geometry as Inventor and other tools, which are designed from the ground up for mechanical design. In the AutoCAD world we usually skip such low level details as actual physical threads (even Inventor kinda-sorta does that), and instead focus on more macro aspects of the design - for example total length of bolt, diameter, and how many.

But its still important to understand basic design concepts and terms such as UNC, pitch angle, and so on so the drawing has correct information.