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16

Muze had a good answer from the Physics side. From a materials perspective, we see things have grain structure, which explains how different fractures occur. Butter cuts smoothly because its micro-structure is rather loosely held. Butter is primarily composed of triglycerides: These short heads (where all the Os are) bunch up, while the long tails spread ...


8

This answer only refers to laser cutting Your main problem will not be the accuracy of the CNC machine, which will be way better than what you can achieve when measuring yourself. The main problem with clean edges is the hole size, if they are too small, say under 6mm diameter (this also depends on the thickness of the metal), the initial puncturing for ...


8

Just do it Since the primary requirement is to not harm the existing structure, anything that is done will have to be manual. Humans are good about dealing with varying conditions. Each lock type, shape, and location is different. We don't trust robots to excavate archeological sites for the same reason. Do no harm Even with humans manually cutting ...


7

A typical "hobbyist laser cutter" with about a 50W power rating won't get you very far cutting metal except for metal foil, but there is no big deal about cutting up to 1 inch thick mild steel plates or tubes with a few kilowatts of laser power. There are plenty of videos on YouTube. Basically, you need enough power to cut quickly before the (high) thermal ...


4

This is a simple shear force problem. However there are a few considerations. You don't need 2 hydraulic cylinders. One should be mobile, the other should be stationary. Below is a simple and quick figure to show how they should align. You should check Sheet Metal Shears they will give you an idea. Below is the simple equation for shear. T is shear stress,...


4

Pulsed lasers release their energy in very short pulses which can have incredibly high peak powers. A run-of-the-mill nanosecond laser will have a peak power in the multi-kilowatt range while a femtosecond laser can easily reach into the megawatt range. In contrast, CW lasers generally do not reach power levels in excess of a few hundred Watts. When these ...


4

Similar to OpticalResonator's answer, I would suggest using the laser/waterjet cutter to mark the hole locations (although you can always mark the holes manually after cutting). You should probably use a punch press to cut the holes, if one is available in your machine shop. Then it's just a matter of selecting the exact die size for the hole you want to ...


4

Probably a skilled metalworker will come along and lough at me for this, but I don't think you can cut to 0.1 mm accuracy with many hand tools. I see these ways: using a small saw (your tubes are fairly small) and then file down to the desired length. I think pliers or bolt cutters could cut through your tube, but will likely chinch it shut Or get a tube ...


3

I can't speak to the mathematics of the heat generated during water jet cutting, but the following points may clarify the situation for you. Heat affected zone is generally with metals where the cutting process will generate enough heat to change the mechanical properties of the metal, essentially locally heat treating the material at and nearby the ...


3

There are cutters that produce circular, slightly tapered plugs, typically 4-12mm diameter. Tapered plug cutter Used in a rigid drill press or milling machine with slow feeds and plenty of lubricant these can cut plugs from soft metals as well as wood and plastic.


3

The tool I would use is metal cutting scissors (or Snips). It's remarkably easy to get a straight cut with these after a little practice. I would first make a cut far from the line (somewhere in the area you're going to discard), to get a feeling for a particular tool cutting steel of a particular thickness. With some experience it is possible to cut as ...


3

Calling a small disc that is 9.5 mm DIA and 1.0 mm thick "a thin sheet of steel" is a bit of a stretch. Any machinist would simply clamp the disc in a suitable vise and mill away the unwanted part. Precision would be a couple orders of magnitude better than your requirement. If you have patience and only need a small number of them done, a pair of pliers ...


2

You should be able to create a non-damaging cutting system if you integrate it with your drive system to control cutting element location. For example, if you use 3+ rubber wheels evenly spaced around the diameter of the device you should be able to reliably fix the device in a static location relative to the pipe walls. I would recommend 4+ high-speed ...


2

Probably the simplest way is to cut it a few mm oversized and grind or file off the excess.


2

Generally an abrasive saw is a bench-top tool. It looks like a miter saw but has a grinding disc instead of a toothed blade. The dist will be on the order of 12-16 inches in diameter for a typical saw. Angle grinders are handheld tools with much smaller discs - usually between 4 and 8 inches in diameter. While there are come very large angle grinders and ...


2

In general they are not interchangable. But if they use the same speed and clamping method then they might be. Best to check with the manufacturer. Some discs are meant to be used only on the outside edge for cutting, whereas others might be used side on (say, 35 degrees) to grind. We have problems in the UK of untrained people using cutting blades for ...


2

It depends a but what you mean by M7 size. Specifying M7 rather than 7 mm diameter implies that the hole is threaded. If this is the case you are better off with a bit of M7 threaded rod cut to length. The best material will depend on the application aluminium male threads are rare but do exist. In most cases stainless should be ok. If you do use a metal ...


2

There is an English translation of "Tabellenbuch Metall", which is the german equivalent. This uses metric DIN standards. https://www.amazon.co.uk/Mechanical-Trades-Handbook-Ulrich-Fischer/dp/3808519134


2

It's called Bernoulli's principle. It works because the fluid has momentum, so doesn't cause equal outward pressure at all points. This principle can be used to convert a high-speed low-volume flow into a high-volume low-speed flow. Since the output flow has more volume than the input flow, additional material is sucked in. The diameter of section 4 is a ...


2

TLDR: Ask someone and do tests. I've worked with hobby level CNC mills (480 watt spindle) and CNC laser cutters (80-100 watt), and I've found that after doing a couple of test cuts, I know what I can and can't do. As ConjuringFrictionForces mentions, talk to your machinists to see what you're likely to get for a result. You're likely going to have to do a ...


1

What I have done before from a very short period of time, I have used a CNC laser cutter to cut 12mm sheet of stainless steel, which I'm sure that you are going to use a thinner sheat metal. My design was something about 135 x 18 mm and the final result was completely nice. But you have to take in consideration that laser has its own cutting diameter "pierce"...


1

This is more of comments than an answer. module = pitch circle diameter / Number of Teeth. A gear with 1mm module and 36T would have a 36mm pitch diameter, not 72" Also, companies such as https://us.misumi-ec.com sells 1mm module 36T gears with selectable bores sizes.


1

A laser would be the best method followed by repetitive razor slicing in ever deeper cuts to avoid frictional deformation. Another method would be cold cuts by freezing the silicone and using a regular mechanical saw. The key to doing it properly is removing deformation from the property of silicone when pressure is applied.


1

Steel with a black passified surface (as mentioned by Jason in the comments) would probably work very well. This surface is Magnetite and has a melting point of 1590°C. The carbon steel has a high thermal mass and reasonable thermal conductivity to pull the heat away from the focal point. Similarly, copper plate black oxide surface treated to have a layer ...


1

Wire EDM and a lathe aren't really directly comparable. Wire EDM is typically used for profile cutting of very hard materials such as hardened tool steel with good dimensional accuracy and may also be useful for producing very small holes or slots. As a result it tends to be quite a specialist process and compared to conventional machining processes on ...


1

I know this is an old question, but I'd like to expand on the general info alephzero stated. In my research for building my own metal cutting CNC laser, I've found that it takes at least a 150 watt CO2 laser to cut through even thin metals. This is also coupled with using a gas (N2 or O2) to either shield the material cut or to help it be cut. Thickness ...


1

I would say that 0.25mm is not very difficult to do. You can use Water jet cutter to be really accurate or if you don't have this possibility, you can simply use a mill or CNC with specific drill.


1

The portable angle grinder that I saw them using on TV looked very effective. In the hands of a competent workman the risk of damage is minimal. With a cutting blade this is more a "geared metal saw" than a grinder per se. Blade size could be selected to be only as large as needed for most locks. Use of a diamond cutting blade that was as durable as ...


1

Here is the formula: https://www.researchgate.net/post/how_to_calculate_cutting_force_required_by_hacksaw_for_particular_work_piece_for_particular_hardness Fc = zckzA*f Where: Fc = cutting force in kg. Zc=number of contact teeths (this number is maximun when the saw reach the diameter of the bar. kz=especific pressure of cutting in kg/mm2 (this value ...


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