All Questions
47
questions
0
votes
1
answer
33
views
DLC wear resistance
I read that a thickness of one micrometer of DLC coating (which, if I understood correctly, shows similar properties to diamond), increases the lifespan of an item plated with it from a week to more ...
0
votes
0
answers
64
views
Belt conveyor roller spring
I wanted to know if anyone could help in this area.
I want to create an inclined conveyor belt where, when a cargo box reaches the top of the conveyor belt, the rollers sequentially move down (maybe ...
0
votes
1
answer
158
views
How much force is acting on the screws I used?
Years ago I built a vertical rack to store long lengths of wood. The rack was built using 2x4" pine scrap. Imagine a typical wall assembly with a single top and bottom "plate" (2x4) ...
- 1
0
votes
1
answer
122
views
What is the best pattern of lightening holes to drill vertically (i.e. along the transverse plane) through a rod of aluminum
I have a 5' long, 2" diameter piece of aluminum round bar. I want to make it at least 30% lighter, while preserving as much rigidity as possible. (The force I'm most concerned about is torsion, ...
- 101
0
votes
3
answers
320
views
Relation between welding bead and outer diameter of a pipe?
How can we find a relation between welding bead and outer diameter of a pipe? Welding bead is inside of the pipe and I am using M.S. pipe.
Dimensions are listed below:
Pipe OD=25.4mm
Thickness=2mm
...
- 57
0
votes
1
answer
765
views
How do I properly scale down a force for scale-down model testing?
I am designing structural frame for a shipping container that would have 8000 lbs of weight stacked on top of it. Of course, i don't access to real size container. I have built a model whose scale is ...
- 1
1
vote
3
answers
55
views
Why we needed to relate internal resistive forces with area (stress)?
When we load a body, say a prismatic bar, axially, internal resistive forces are developed within it to oppose the elongation or compression. What was the need of relating these internal resistive ...
- 859
1
vote
4
answers
746
views
What thickness of steel bar/pipe for home gym?
I would like to build a rack for my home with a pull up bar. I'm leaning towards a steel pipe with a diameter of 42.4 mm, but have no idea how to determine what wall thickness is needed so that the ...
- 13
0
votes
2
answers
65
views
Weight distribution on sliding or “pocket” doors
Does anyone know if hollow sliding/pocket doors have a weight/more dense wood at the bottom of the door to prevent from swinging?
- 1
4
votes
1
answer
12k
views
Why is the Stress vs strain diagram preferable to the Load vs displacement diagram?
I’m really unsure what is the difference between stress vs. strain and load vs displacement graphs and why stress-strain is better.
I know that the units are different:
stress is in MPa and the load ...
- 41
-1
votes
2
answers
146
views
Pressure vessel wall dimensions
I am trying to design a small cooling setup which has two parts: the compressed air vessel and the turbines. My understanding is that the compressed air, upon being released, passes through the ...
- 98
0
votes
3
answers
86
views
Economical difference with high-pressure vessel design pressures for fixed volume
Suppose space is not an issue and I need a fixed volume of compressed air (for storage), say 1m³. Is it more economical to manufacture a thick-walled vessel but with a smaller volume or a thin-walled ...
- 98
0
votes
2
answers
84
views
Modelling an annular ring
I am trying to model the shear failure of an annular ring with a uniformly distributed pressure, the ring is hashed out. I am not sure how the problem would be modelled as part of the ring is ...
0
votes
1
answer
627
views
3D printer printing out cotton-candy like material after repeated use
I recently purchased a JGMaker Magic 3D printer. It worked well for about 3 months [first picture], but now it is having a lot of trouble.
As you can see in the images below, when printing new pieces, ...
1
vote
1
answer
424
views
Initial shallow gradient in measured stress strain curve
What's causing the initial shallow gradient of the stress strain curve of ceramic in this graph?
The rest of the curve is a straight line alright until the yield point.
Edit: the material being tested ...
- 81