Worth taking an AutoCAD course if i'm studying Engineering?

KaHn said:
Also to the CAD Designer, lets see some calcs for what you design and which standards they conform to, then I will tell you why we check the designs.

KaHn
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That logic doesnt work in the Aerospace or Automotive industry Im afraid. You have stress engineers and CAE analysts with designers and draughtsmen forming the other half of the process as the components go through their various design gateways an iterations.

Im not sure there are BS standards for pyrotechnic bonnet hinges? Or air to air refueling probe brackets on composite spars. Generally the centres of competancy or excellence are the method owners aswell as component responsible. Anything done purely on paper wont be accurate or fast enough such is the complexity of the models.

Dont bother with autocad, only time i used it was for shapes of caravan furniture for a CNC operator to use to make a program for his MDF. I think I would have prefered a drawing board, there was no master model oso pointless having it on CAD.
 
Jonnycoupe said:
That logic doesnt work in the Aerospace or Automotive industry Im afraid. You have stress engineers and CAE analysts with designers and draughtsmen forming the other half of the process as the components go through their various design gateways an iterations.

Im not sure there are BS standards for pyrotechnic bonnet hinges? Or air to air refueling probe brackets on composite spars. Generally the centres of competancy or excellence are the method owners aswell as component responsible. Anything done purely on paper wont be accurate or fast enough such is the complexity of the models.

Dont bother with autocad, only time i used it was for shapes of caravan furniture for a CNC operator to use to make a program for his MDF. I think I would have prefered a drawing board, there was no master model oso pointless having it on CAD.
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What you are talking about there is FEA and non linear analysis, basically no designer will do that by hand but what he will use is standards for what saftey factors they will use throughout the design or failing that do full fatigue life analysis and also exact loading parameters and take the material to yield. Also if you have a CAD operator doing FEA(Not on about running the analysis but producing the meshes) with out a degree (i.e. as ethics said just doing drawings) thats really really dangerous, yes FEA and even CFD are becoming more and more user friendly but a one of principle engineers said "put crap in get crap out".

My comment about standards was mostly aimed at "ethics" who stated he works in the oil and gas field of engineering which has more safety factors than any other industry as the time factor in this is greater than the cost (things done quickly but over engineer > clever engineer done over a long period of time).

Think of it this way to have a waterproof watch you can have a £2.99 watch in a plastic bag so why do people insist on only a Rolex designed to 3000m should be used to tell the time underwater?

KaHn
 
KaHn said:
What you are talking about there is FEA and non linear analysis, basically no designer will do that by hand but what he will use is standards for what saftey factors they will use throughout the design or failing that do full fatigue life analysis and also exact loading parameters and take the material to yield. Also if you have a CAD operator doing FEA(Not on about running the analysis but producing the meshes) with out a degree (i.e. as ethics said just doing drawings) thats really really dangerous, yes FEA and even CFD are becoming more and more user friendly but a one of principle engineers said "put crap in get crap out".
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Thanks for that, i didn't know it was called FEA... A good stressy will throw a crap mesh away from second 1.
 
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KaHn said:
Think of it this way to have a waterproof watch you can have a £2.99 watch in a plastic bag so why do people insist on only a Rolex designed to 3000m should be used to tell the time underwater?

KaHn
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A Rolex is this example could be classed as a solution as oppose to something you need to wrap in a plastic bag :confused:

Seems to me if you want a broad engineering field dont get into oil and gas :D
 
Jonnycoupe said:
Thats for that, i didn't know it was called FEA.
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FEA is Finite Element Analysis, basically taking a 3D inventor/solid works/Pro E and applying loads(or temperature or deflections) to it to correspond to a real life scenario using programs like Anysis/Abaqus(2 main ones), the CFD (Computational Fluid Dynamics) depending on if you are looking at internal (pipes) or external (flow around a body) will also play a different part to the analysis but can be combined using Cosmos iirc and other specilised software.

Mesh sizes can play a huge part in the computing time and also the accuracy of the design, for example take the aspect ratio of the mesh, if you use a AR >>1 you will get inaccuracy in the design (forgotten the exact name for it but will look later on).

Another problem I have seen with mesh produced by CAD operators is that they leave rounded edges/chamfers/fillets basically lots of things which don't affect the end result much but due to them being non-regular will sometimes require an increased mesh size to mesh correctly which can add hours to the computational time which over the life of a project can amount to a huge amount of over analysis.

KaHn
 
KaHn said:
Another problem I have seen with mesh produced by CAD operators is that they leave rounded edges/chamfers/fillets basically lots of things which don't affect the end result much but due to them being non-regular will sometimes require an increased mesh size to mesh correctly which can add hours to the computational time which over the life of a project can amount to a huge amount of over analysis.

KaHn
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My comments were about package engineers on this project, we had one reading a drawing upside down in our meeting and asking why the bouyancy tank sat at the bottom. Not sure why you got uppity tbh.

What you have described above is true, i spend a lot of time modifying alternate versions of components for simplicity for Ansys. However fillets and chamfers (or ratholes, depends who/where is manufacturing) are an integral part of the manufacturing process, a lot of things in this industry are forged, which must then be machined, stresses and machining techniques require that the above features are present, perhaps one of the most important links between draughties and Engineers, how will it actually be fabricated/made. You need to know how to detail an item for forging AND machining, tolerances (desired and achievable) the list goes on.

Everyone plays their role, to get back on track for the OP learning Autocad in his case has a number of benefits:

* Looks nice on a CV
* Can assist with calcs/nesting drawings etc. etc.
* Can review technical drawings from supplier
* Can draw quick schematics etc.

It will NOT enable you to construct technical drawings to a standard (BS 308, 8888 or the equivelants ISOs), the course is for the software, not how to apply it.

Personally £500 seems excessive to me, i'd consider that if and when it becomes neccesary for the job, i'd try a bit of self education and see how you get on.
 
Im taking the Pi55.

Although quoting solidworks/3 inventor and Pro E as FEA programs amuses me greatly. No wonder you can use hand calcs as an alternative.

I think there must be some seriously lack training schemes if you can make generlisations that CAD operators leave filets on components. Ive never come across somebody that did. Again if it did happen mr stress engineer/CAE analyst or heaven forbid, FEA engineer :eek::p would send it back and ask for a new mesh.

Thanks for the top up degree though.
 
Jonnycoupe said:
Im taking the Pi55.

Although quoting solidworks/3 inventor and Pro E as FEA programs amuses me greatly. No wonder you can use hand calcs as an alternative.
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Solidworks has Cosmos as its FEA package, i've heard some swear by it and some think its a bit Mickey Mouse, not used it myself though.
 
Jonnycoupe said:
A Rolex is this example could be classed as a solution as oppose to something you need to wrap in a plastic bag :confused:
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Both are solutions, one is just a more sophisticated solution than the other.

Jonnycoupe said:
Seems to me if you want a broad engineering field dont get into oil and gas
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As always it depends on what side of it you go into, Engineering Consultancy(Companies who generally design small critical/complex bits) is different to Contractors (the companies who go out and do the job) which is different to the Operators (which drill the oil). But for Oil and Gas not being a broad field this is a list of things I have seen while in the Oil and Gas.

Material types I’ve designed for:

GRP
CRP
Carbon Steel
Alloy Steel
Thermoplastics
Copper based alloys

Analysis Types I’ve been done:

Stick frame analysis
3d FEA
Dynamic Riser Analysis
CFD
Hydrodynamic loading on fixed structures
Hydrodynamic loading on structures being deployed
RAO Analysis
Dynamic Vessel Motion Analysis
Fatigue analysis

Also as it has been stated the FEA programs I quoted were Ansys and Abaqus, ProE/Inventor/Solidworks are CAD Tools which have been expanded to include meshing tools for Engineers to use.

Ethics I didn't mean to get on to you but what you described was a Project Engineer, I have had my fair share of problems with them, but your "holier than thou" was what got my back up sorry, as for manufacturing tolerences and processes, they were all covered in my Degree and have been updated during my time in industry.

KaHn
 
KaHn said:
as for manufacturing tolerences and processes, they were all covered in my Degree and have been updated during my time in industry.

KaHn
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Your lucky then, my degree in Aerospace (the benchmark for safety factors and RF) didnt cover FEA. Glad you covered it for me :D
 
Ethics said:
Solidworks has Cosmos as its FEA package, i've heard some swear by it and some think its a bit Mickey Mouse, not used it myself though.
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Yeah but the results will be from cosmos not solidworks. Solid works would just provide a mesh and there no reason any other program can do that. They are simply made/distributed by the same vendor.
 
Jonnycoupe said:
Your lucky then, my degree in Aerospace (the benchmark for safety factors and RF) didnt cover FEA. Glad you covered it for me :D
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Mine did at UMIST/Manchester (same degree), also covered it when I was doing my MSc in Mechanical Engineering but left to work in the Oil and Gas half way through.

KaHn
 
KaHn said:
Material types I’ve designed for:

GRP
CRP
Carbon Steel
Alloy Steel
Thermoplastics
Copper based alloys

Analysis Types I’ve been done:

Stick frame analysis
3d FEA
Dynamic Riser Analysis
CFD
Hydrodynamic loading on fixed structures
Hydrodynamic loading on structures being deployed
RAO Analysis
Dynamic Vessel Motion Analysis
Fatigue analysis
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For what components though, that was my point. Pipes and pipe? Doesnt sound too varied to me.
 
Jonnycoupe said:
Yeah but the results will be from cosmos not solidworks. Solid works would just provide a mesh and there no reason any other program can do that. They are simply made/distributed by the same vendor.
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As stated before Inventor/Solid Works/Pro E are drawing tools, Ansys and Abaqus are FEA programs.

KaHn
 
KaHn said:
Mine did at UMIST/Manchester (same degree), also covered it when I was doing my MSc in Mechanical Engineering but left to work in the Oil and Gas half way through.

KaHn
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Seriously you're annoying me now. I was taking the mick again. Are you reading the posts in this thread?

Im fully aware of FEA, for some reason you felt the need to pull me up on FEA when i used stress engineer/CAE analyst as they are the two job descriptions you find more often. What confuses me is that you think these jobs must involve no FEA when that is all they use/do in support of the design process/certification.
 
Jonnycoupe said:
Seriously you're annoying me now. I was taking the mick again. Are you reading the posts in this thread?

Im fully aware of FEA, for some reason you felt the need to pull me up on FEA when i used stress engineer/CAE analyst as they are the two job descriptions you find more often. What confuses me is that you think these jobs must involve no FEA when that is all they use/do in support of the design process/certification.
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No what I am saying is that the use of FEA Programs should be limited to those who know the mechanics behind them, not just how to run the interface infront of them like some computer game.

KaHn
 
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