Picking the start point seems to be the key

[Vagulus]

Efficient modelling seems to depend a lot of selection of start point and sequence of actions. This is exercise 6.118 from

Giesecke F.E., Mitchell A., Spencer H.C., Hill I.L., Dygdon J.T., & Novak J.E. (2014). Technical Drawing. Upper Saddle River (NJ) USA: Prentice Hall

 

 

 

I have been pondering where to start and what to do for quite a while now and I don't see any clear favourite.

 

Where would you begin? ... and Why?

[JD Mather]

The hole has the tightest dimensional tolerance and no other "obvious" datum with symmetry.

But this is a challenging part, I recommend that you pick a different one.

 

[Vagulus]

But this is a challenging part, I recommend that you pick a different one.

 

You are right. It was a swine. I won't mention how long it took but I think I have it! I would appreciate constructive criticism.

 

 

 

 

You can download the IPT here.

 

 

Currently, I work on a general principle that holes, bores, and fillets are tidy-up jobs at the end. In retrospect, I think it would have been wise to create the model as an un-machined solid with all the edges filleted at R0.25 - then do the cuts and holes etc. That would mirror the way it would be done in industry and would also get rid of the problems found in Fillet 3 (R0.1) which, after machining, I can't do any other way. That's open for comment too!

[JD Mather]

I don't go to third party websites to download files.

Roll up the EOP and attach it here.

 

On these castings it is frequently necessary to model as the full casting to get the correct fillets and then do machining features. You are doing that as I would.

 

Consider on the casting what machining feature will be used to locate/inspect all or most other operations.

[Vagulus]

I don't go to third party websites to download files.

Roll up the EOP and attach it here.QUOTE]

 

 

 

That's a website I own. The IPT is 5KB too big to attach here but the ZIP just snuk in. 6-118_Horizontal_Bracket_for_Broaching_Machine.zip

What's an EOP?

Edited June 13, 2014 by Vagulus

[JD Mather]

Here is the same part with the red End of Part marker (EOP) rolled up.

Note that the file size is significantly smaller (zipping would further reduce the size).

 

Drag the red EOP down step-by-step to see how the part was built.

Extrusion 9 makes no logical sense. Could have simply edited, changed to Cut midplane through all

but instead you left the error and added Extrusion 10.

 

6-118_EOP rolled up.ipt

[Vagulus]

Thanks for that JD. I take the point on Extension 9.

If that was all that could be improved, I'm going to take that as a compliment coming from you