tools, materials & knowledge for model makers
With any milling machine you need mass and stiffness, so I decided to make a Genmitsu 3018-pro stiffening bracket. The template was cut out from a thick-ish piece of cardboard. You can see that I had to extend the template to add the leg that fits onto the top of the side chassis rail. Using … Read more
Having used particle damping in the column of the milling machine and on the workpiece of the cnc it was time to look at it in detail. Particle damping works based on impact and friction, depending on the size of the particles this can be one or millions. Studies show that most of the energy … Read more
A weighting sound is the most generally used filter when making overall noise measurements. The attenuation of the sound signal with an A-weighted filter corresponds to the fact that the human ear is not as sensitive to sound of the lower frequencies as it is at the higher frequencies. The A-Weighted Sound Level is a … Read more
There are a number of different community noise criteria measurements, some of which are described below: CNEL = Community Noise Equivalent Level This is used to characterize average sound levels over a 24-hour period, with weighting factors included for evening and nighttime sound levels. Leq values for the evening period (7:00 p.m. to 10:00 p.m.) … Read more
Understanding frequency, wavelength and speed is fundamental to everything around us. From noise and vibration, chatter on a lathe tool to the light we experience from objects. Waves move energy from one place to another without any accompanying matter. Sound waves, ocean waves and electromagnetic waves are some of the examples; other, more complicated types … Read more
Room acoustic modes occur at frequencies at which sound waves in a room resonate (in the form of standing waves), based on the room dimensions. The acoustic modes will “colour” the sound, ie enhance certain frequencies and dull others. Therefore, the standard modal approach for designing a room with good acoustics is to create as … Read more
Room acoustics is a huge subject in it’s own right, but I wanted to share some basics. A basic level of knowledge will help if you are trying to reduce the noise levels in a workshop or position your speakers in the optimal location. The trend of creating large open living areas that are decluttered … Read more
There are a number of different types of acoustic chambers and rooms. Some are defined very specifically and others more loosely. These rooms are mainly used by noise and vibration measurement specialists. Acoustic chambers and rooms are quite specialist rooms to design, build, operate and maintain. Often the design of these rooms will be done by … Read more
Why am I sand bagging the milling machine? A great way to add damping to a structure is to use sand. Loud speaker stands are commonly damped using sand. Thus adding mass and damping to the structure. This means the stands don’t vibrate and so radiate sound. The milling machine in question is the Sieg … Read more
Vibration damping is the dissipation of energy in a system, either through time or distance. Damping will reduce the vibration amplitude. Hence reducing the radiated sound or reducing the vibration and hence improving the tactile quality. The term is generally applied to the vibration of a structure owing to the internal dissipative properties of the … Read more