Hot answers tagged

16 votes

How can a knife cut through butter?

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-...
user avatar
  • 5,303
8 votes
Accepted

How should I go about adding holes to laser or water jet cut sheet metal?

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 ...
user avatar
8 votes

What would be a practical way for removing thousands of padlocks from valuable bridge railings?

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, ...
user avatar
  • 10.6k
7 votes
Accepted

How to handle reflections when cutting metal with a laser?

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 ...
user avatar
  • 12.5k
4 votes

Force required to crop/cut a mild steel bar

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 ...
user avatar
4 votes
Accepted

Difference between continuous wave laser and a pulsed laser

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 ...
user avatar
4 votes

How should I go about adding holes to laser or water jet cut sheet metal?

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 ...
user avatar
4 votes
Accepted

Cutting tool for hollow tubes

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 ...
user avatar
  • 4,618
4 votes
Accepted

Why laser cutting speed suddenly decrease when cutting sheets from 1 to 3mm thickness then stabilize?

To see why this graph can only have a hyperbolic shape, it can help to take a look at the energy balance of the laser cutting process with absorbed laser power $P_A$. $$P_A = \underbrace{vtw}_{V_M}\...
user avatar
3 votes

Why is there no heat-affected zone with water jet cutting?

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 ...
user avatar
  • 1,578
3 votes
Accepted

Is there a drill adaptor or attachment tool for cut a metal solid cylinder

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 ...
user avatar
3 votes

How can I cut a thin (1mm) sheet of stainless steel with high precision?

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 ...
user avatar
3 votes
Accepted

How can I cut a thin (1mm) sheet of stainless steel with high precision?

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. ...
user avatar
  • 6,719
3 votes

Cutting mechanism for a robot in confined spaces

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 ...
user avatar
3 votes

Smallest possible elliptical hole

It's unlikely you'll be able to accomplish your goal. Lasers and high pressure water jets are not the tools for the smallest possible features. Electrical Discharge Machining (EDM) is capable of ...
user avatar
  • 6,117
3 votes

How would I use a laser to cut a moving solid object?

However, usually lasers come as a point, which means that we'd have to make the laser head move in quite an exotic curve, which will slow down our cut rate. The limiting factor is usually the cutting ...
user avatar
  • 7,519
3 votes

I would like to cut out arcs of the circumference of a cross section of PVC pipe so the arcs are precisely 60 degrees. How would I do this?

Use a pillar drill and a rotating vice which has graduations on it. Drill a hole at 0 degrees then rotate for hole at 60 degrees. Repeat for other holes then join with saw cuts, dremel etc.
user avatar
  • 13.6k
2 votes

Force required to crop/cut a mild steel bar

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 ...
user avatar
2 votes

Cutting mechanism for a robot in confined spaces

I would suggest a Dremel-like cutting wheel positioned at the front which can be rotated around 360˚ such that the wheel stays parallel to the inner surface of the pipe. The small diameter of the ...
user avatar
  • 5,930
2 votes

How can I cut a thin (1mm) sheet of stainless steel with high precision?

Probably the simplest way is to cut it a few mm oversized and grind or file off the excess.
user avatar
2 votes
Accepted

Difference between an angle grinder and an abrasive saw

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....
user avatar
  • 4,501
2 votes

Difference between an angle grinder and an abrasive saw

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 ...
user avatar
  • 66
2 votes

Is there a drill adaptor or attachment tool for cut a metal solid cylinder

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....
user avatar
2 votes
Accepted

Gear cutting books in metric system

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/...
user avatar
2 votes

How does water flow in the water jet cutter nozzle?

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 ...
user avatar
  • 11.2k
2 votes

How should I go about adding holes to laser or water jet cut sheet metal?

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 ...
user avatar
2 votes
Accepted

I would like to cut out arcs of the circumference of a cross section of PVC pipe so the arcs are precisely 60 degrees. How would I do this?

Put a hex-head plug in each end so you have a flat.
user avatar
  • 3,381
2 votes

Is it possible to tap a hole partially through a 3mm aluminium sheet?

Usually holes are tapped to a depth of 1.5 times the diameter, and more for softer metals. As aluminium is soft, then the thread will be engaging just one turn which won’t take much load at all. A ...
user avatar
  • 13.6k
1 vote

How should I go about adding holes to laser or water jet cut sheet metal?

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 ...
user avatar

Only top scored, non community-wiki answers of a minimum length are eligible