# Search results

1. ### Choosing a stepper motor

What you describe sounds rather like a triangular displacement function. This is physically impossible because of the infinite accelerations required to reverse the direction at each turning point.
2. ### Question about Free-Body-Diagrams (MSc Thesis)

Writing Fn*mu for the friction force might be valid if you assume that there is slipping at the point of contact. It is usually not true if there is no slip.
3. ### Fatigue life of a simple beam

It seems likely that it would simply be an implementation of one of the standard approaches used for machine design such as the Goodman line.
4. ### Fatigue life of a simple beam

Well, I really don't know. After all, you are the FEAnalyst, not me. It would seem logical that anything that can be done in a finite number of computer steps could also be done (in principle) with a finite number of pencil and paper steps. Someone who does FEA would surely know how that works...
5. ### Fatigue life of a simple beam

You should research the standard fatigue test using an R.R. Moore machine. This is the way most fatigue data is acquired. I think the short answer to your question is simply "no." There is always some scatter in fatigue data due to small imperfections in the material, the specimen geometry...
6. ### Question about Free-Body-Diagrams (MSc Thesis)

@Laura85 You say in #3 that you are assuming no friction or slip. Looking at the first problem (the rolling disk striking the step), these two assumptions are incompatible. If there is no friction any where, then the impact at A must involve slip. If there is no slip, this is only possible if...
7. ### German contributions to aviation

One of the major German contributions from the 1930s was S.F. Hoerner's books, Fluid Dynamic Drag, and Fluid Dynamic Lift. The contain vast amounts of empirical data.
8. ### Capped pressure vessel - strength and stability

I suggest the OP also look at Den Hartog's Advance Strength of Materials text. I seem to recall considerable discussion of this problem there.
9. ### Choosing a stepper motor

If you want continuous rotation, why would you use a stepper motor?
10. ### Other Recent Grad with Job market Questions

SULI?? CCI?? I doubt that these initials mean much to most folks. This is communication failure.
11. ### Other Recent Grad with Job market Questions

@StatGuy2000 I'm not really advising him to go to graduate school. I was only presenting the only possible options I see open to him. While I agree that most schools will want a higher GPA, that is not always the case; there are exceptions. Actually, I think the OP is in an awkward position...
12. ### Other Recent Grad with Job market Questions

It seems that you chose a field of study for which there is a very limited market at the BS level. That leaves you two options: 1) Find the finances to go on to graduate school to get to a markeable level (probably nothing less than a PhD) 2) Look for work outside your chosen field. This is...
13. ### How hard is the maths for Mechanical Principles and Thermo in ME studies?

This question is essentially an imponderable. The math required for any particular course is not hard if you already know it, but it may be insurmountably difficult if you've never seen it before. No one but you can even guess at the answer in your case.
14. ### Calculating Hydraulic Press Pressure on a Skatebaord :)

I'd suggest replacing it for best results. Now that it is split, it can no longer support shear on that surface and an intact beam would.
15. ### Calculating Hydraulic Press Pressure on a Skatebaord :)

Actually, there is no need for the bolts to pass through either horizontal member. If the side members (or the scab plates) extend far enough above and below the horizontal members, the bolts can simply pass across above the top member and below the bottom member. This will have the advantage of...
16. ### Maximum shear stress in an assymetric cross-section

Then this is a prime opportunity to work it out for yourself. No telling what you may learn in the process!
17. ### Maximum shear stress in an assymetric cross-section

If we talk about an L section (an angle), how will it be loaded? Parallel to one of the sides (in which case you have non-principal axis bending), or will it be loaded along a principal axis?
18. ### Calculating Hydraulic Press Pressure on a Skatebaord :)

The scab plates that connect sides to top and bottom beams appear very short. This puts the bolts quite close to the ends of the side members, increasing the likelihood of a tear-out.
19. ### Calculating Hydraulic Press Pressure on a Skatebaord :)

So, did you make any calculations before building your frame, or did you just eyeball it?
20. ### Linear Actuator -- Why is this not working?

Depending on your system, there can be a lot of friction in that pulley system. This does not seem to be taken into account in your work.
21. ### Form of a track in a mechanism

Can you provide a better diagram? I really cannot follow what you hope to accomplish here at all.
22. ### Plate - bending moment equation

Have you checked Timoshenko's Plates & Shells? I don't know if this is included, but that would be the most likely source I can think of.
23. ### What is the efficiency of a Hobson's joint?

I suggest that you work it out for yourself, initially based on frictionless connections. If you apply a torque T1 to the input, what is the output torque, T2? I have not worked this out, but I think you will find that it is angle dependent.
24. ### How to increase a hole/thread diameter in gold

The chances of destroying the watch are pretty high. Watches are made to a level of precision rarely ever found in other industries. Many years ago, I worked for Hamilton Watch Co., and old-line American watch company. I was simply astounded at the precision involved in every aspect. I would...

UDL??
26. ### Code / Software for Dynamic Balancing (Free / Open Source)

It would be really silly to continue searching for your shoes after finding them.
27. ### Code / Software for Dynamic Balancing (Free / Open Source)

Got it! Sorry I missed that.