Anyone here planning to take PE machine design in April 2018

[PARSCORA]

I'm looking for suggestions on what others have studied.  I have studied from the merm chapters 45-60 and I did all corresponding practice problems.  I took the pro guides practice exam and did pretty well.  Any thoughts on what else others have reviewed?  I also did some review of dimensioning etc, economics and ethics.

My thoughts on the practice exam were that the problems were def much easier than the merm practice problems.  I do not know which is more reflective of the test since I haven't taken it yet.  There are several mistakes on the test, but overall I think it would be worth the $35 for additional practice problems and a gauge of where you are.

 

[Audi Driver P.E.]

I'm looking for suggestions on what others have studied.  I have studied from the merm chapters 45-60 and I did all corresponding practice problems.  I took the pro guides practice exam and did pretty well.  Any thoughts on what else others have reviewed?  I also did some review of dimensioning etc, economics and ethics.

My thoughts on the practice exam were that the problems were def much easier than the merm practice problems.  I do not know which is more reflective of the test since I haven't taken it yet.  There are several mistakes on the test, but overall I think it would be worth the $35 for additional practice problems and a gauge of where you are.

I think it would be a good idea to know your Shigley inside and out.

 

[Ramnares P.E.]

I think it would be a good idea to know your Shigley inside and out.

Second this.

 

[emmajuwa]

Does everyone agree to the solution provided by NCEES to their practice examination question 533 in the Errata? Looks like the concept of buckling is not clear especially with them having all solutions to the Buckling problems wrong and had to correct them, but I don't agree with solution to problem 533. The maximum load or design load in the hydraulic cylinder is not the critical load if you are applying the buckling factor of safety. Maybe I'm wrong. I'd appreciate your opinions.

 

[Slay the P.E.]

Does everyone agree to the solution provided by NCEES to their practice examination question 533 in the Errata? Looks like the concept of buckling is not clear especially with them having all solutions to the Buckling problems wrong and had to correct them, but I don't agree with solution to problem 533. The maximum load or design load in the hydraulic cylinder is not the critical load if you are applying the buckling factor of safety. Maybe I'm wrong. I'd appreciate your opinions.

Looking at the original solution (not the errata) the mistake I see is that the problem statement says the yield strength is 36,500 psi but in the solution they used 73,000 psi. The steps are all correct for a buckling analysis. I have attached the solution with σY = 36,500 psi, for which the minimum rod diameter is 1.572 in; choice (C) 

What they did in the errata is not a buckling analysis at all. They are calculating the rod diameter that would cause failure due to the compressive stress matching the compressive yield strength (adjusted by a FS). That way they calculate a minimum rod diameter of 1.11 in. Since the rod diameter required to protect agains buckling is bigger, then one would pick it because it protects also against yielding. 

Therefore, the correct answer seems to be (C)

 

[emmajuwa]

Looking at the original solution (not the errata) the mistake I see is that the problem statement says the yield strength is 36,500 psi but in the solution they used 73,000 psi. The steps are all correct for a buckling analysis. I have attached the solution with σY = 36,500 psi, for which the minimum rod diameter is 1.572 in; choice (C) 

What they did in the errata is not a buckling analysis at all. They are calculating the rod diameter that would cause failure due to the compressive stress matching the compressive yield strength (adjusted by a FS). That way they calculate a minimum rod diameter of 1.11 in. Since the rod diameter required to protect agains buckling is bigger, then one would pick it because it protects also against yielding. 

Therefore, the correct answer seems to be (C)

View attachment 10850

Thank you so much. It makes sense.

 

[PARSCORA]

I have struggled with materials selection questions.  Anyone have some good references to help with this?  Currently I have what is available in the merm, machine design handbook and mechanical engineering design.  

 

[PARSCORA]

Has anyone else taken the lindeburg machine design and materials practice exam?  On problem 9 I get a different answer then they did.    I calculated as attached, is this correct or is the book correct?

 

[Kloeb222]

Can you post the problem?

 

[PARSCORA]

Here is the problem

 

[Kloeb222]

I think there is an error in this problem.

The problem statement says the weld has a 3/16" throat but the figure shows a 3/16" leg. Your calculations look to be correct for a 3/16" weld leg. If a 3/16" throat is used, the max allowable force comes to 3387 lbf. Answer B.

Do the rest of the problems seem comparable to the NCEES practice exam in level of difficulty? With a couple weeks left i am running out of practice problems to do.

 

[ticrazy05]

Hey @sbrookef can you please share with me the materials: [email protected]

 

[ccbiggs]

I passed MDM this October 2017! I have PDFs of material I found useful that I'm happy to share in a secure file transfer -- google drive? Other methods? You'd then print it out and put it in a binder.

Could you send to me as well? [email protected] 

Thanks !

 

[Victor1990]

can some send the pdf material 

[email protected]