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0 votes
1 answer
64 views

Material suited for fixing leakage in liquid nitrogen dewar

I need to fix a leak on the inside of a liquid nitrogen dewar which acts as the coolant tank for a spectroscopy CCD camera. Due to the design of the camera, I unfortunately can only access the inside ...
Mika R.'s user avatar
0 votes
0 answers
42 views

Tolerances in the manufacture of mechanical parts (plastic)

It is necessary to make an adapter ring for connecting the smartphone to the microscope eyepiece (turn from ABS on a lathe, or 3D printing). Microscope eyepiece diameter is 33mm. What should be the ...
minto's user avatar
  • 103
0 votes
0 answers
13 views

How can I calculate the maximum center load on a horizontal cellular glass tile; supported along its edges, before it breaks?

Insulating cellular glass boards or tiles are designed to sit on a flat load-bearing surface. I want to consider the situation where the base is concave so the tile is only supported on its edges. I ...
CuriousGeorge's user avatar
0 votes
0 answers
40 views

How can I reduce noise from pushrods in an assembly without using grease/oil?

I have an assembly which consists of a row of vertically-oriented nylon pushrods (each 5/16" in diameter, colored green in the attached pictures), and two black pieces of laser cut delrin ...
user10264746's user avatar
2 votes
0 answers
28 views

What determines the rate of electron discharge machining (EDM) for different materials?

Wire EDM makes no contact with the work piece and disregards hardness. I am using EDM to cut different materials, and I notice a clear distinction between the rate each material gets cut. For example, ...
FlakR's user avatar
  • 131
1 vote
1 answer
52 views

Potential Problems of Excessively Hard Shaft

Will there be any issues if we make the shaft too hard? Hardness being a surface property may prevent surface scratches and wear, could it lead to any problems in general?
Max's user avatar
  • 88
0 votes
1 answer
48 views

Why the size of top and bottom rollers is different in three point bend test?

In a short beam shear testing of polymers, the configuration is such that the top (loading) roller is bigger than the bottom (support) rollers. Why is this the case, and what happens when the size of ...
Uz1's user avatar
  • 1
0 votes
1 answer
18 views

Calulating the compression deformation using strain data measured by strain gauge _ material engineering

I'm studying material engineering and conducting some experiment. The experiment was measuring the strain of long steel bar. The bar is compressed from left side and deformed shortened. Using strain ...
조범희's user avatar
1 vote
2 answers
65 views

Replicating an impact impulse

I am building a test-rig for a device. I have operational data showing the device experiences impact loads resembling a half-sine pulse with width dt and magnitude F. The test rig's purpose is to ...
engstudent296's user avatar
0 votes
1 answer
44 views

Valox 420 30% glass wear

I am seeking assistance regarding thermoplastic material wear on a new product I am developing. The attached image is molded out of Valox 420 30% glass. In the left side image, the locking dents are ...
Rob Montgomery's user avatar
0 votes
1 answer
71 views

What would be an ideal material to use for O-rings on a canister in a lubricant-less, high-velocity pneumatic tube system?

I am interested in building an experimental lubricant-less pneumatic tube system in which the canister will be propelled up to a high-velocity, reaching a peak velocity of approximately 100 m/s before ...
user57467's user avatar
  • 303
1 vote
0 answers
37 views

replacing the sound a small toy speaker makes

not sure if this counts for this community, and im open to suggestions where this would belong but im looking for advice. i have no experience in working with physical hardware, as the limited ...
Vi H's user avatar
  • 11
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) ...
Rob W.'s user avatar
  • 1
0 votes
1 answer
311 views

What's the difference between amount of phase and chemical composition of the phase

I don't understand the difference between chemical composition and the amount of phase, why does the chemical composition of the phase not add up to 100%. For example in the image below the chemical ...
Youssef Mahmoud's user avatar
0 votes
1 answer
37 views

How to determine the minimum thickness for a Red Dot Sight mount built in aluminum?

I'm designing what is called a "Red Dot Sight Mount" (see image below) for a handgun. Disclaimer: this kind of part is not regulated (at least not in any country that I can think of) and ...
GuiTeK's user avatar
  • 101

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