Those involved in metal fabrication are experienced in fabricating with hollow tubing which means they are also well aware of what a tube notcher is and how it works. Although a hole saw tube notcher is frequently used, it is not the only way to undertake the operation.
A tube notcher is used in many different applications and processes; typical examples that a consumer would be well aware of include bicycle frames, domestic plumbing, outdoor furniture, etc. These operations use reasonably small diameter tubing but the notching process is also employed with much larger tubes that are used as structural supports, roll cages for high performance automobiles and more.
The choice of tube notcher depends to an extent on the shape of the notch, the characteristics of the material being notched and the notch shape, there is also volume to consider; the process used for low volume manufacturing is one thing, the process used for high volume production is something else all together.
The notching process:
Tubes are notched prior to joining them by welding, soldering or brazing. The joint is often a simple “T” but it can be of any angle and either one tube or both tubes can be notched prior to welding.
The objective is to create a shape on the end of one tube that will mate with another tube.
There are various processes that can be used:
Hole saw: A hole saw is a circular cylinder which either has teeth ground in the edge or the cutting surface can be embedded with industrial diamonds. This type of tube notcher is relatively inexpensive and it is portable. The tube section is held rigidly in a clamp and the saw is brought down on the surface.
Drum sander: A less expensive approach to notching the end of a tube is using a drum sander. As the metal is being ground away rather than clean cut, a sander is dirtier, dustier and generates considerable heat which may distort the tube.
End mill: An end mill is an ideal choice; if you own a CNC milling machine which is only found in high volume, sophisticated machine shops.
