Horizontal Bandsaw Introduction

From CoMakingSpace Wiki

This is the content required for an introduction to our Horizontal Bandsaw - reading this does NOT replace the mandatory session with a tutor! It will make it a lot quicker though ;-)

If you need this Introduction, please reach out to the following tutors: Johannes, Lukas

Let's begin! First off, make sure you have read the machine's manual (see respective "InfoBox" on the machine page).

Safety

Personal protection: Protection - goggles.svg Protection - hearing.svg

Dangers Precautions
Danger - draw-in.svg
entanglement/draw-in hazard
  • unplug the machine before opening the blade housing to change speeds
  • do not wear loose clothing or jewellery and keep long hair under a hairnet or in a tight bun
  • gloves: make an informed decision (as with the table saw) - they will not protect you against the blade, but against sharp or hot workpieces after cutting!
sharp, quickly moving blade that is only held in place by its own tension
  • always unplug the saw and wait for the blade to stop before opening the case of the machine
  • keep all body parts at least a hand's width away from the blade whenever the saw is running
  • do not remove jammed cutoff pieces until blade has stopped
chance of kickback:
  • loose workpieces may buckle sideways and can be thrown at high speeds
  • the blade can bind with the material
  • you MUST ensure the workpiece is properly secured (touching the table and clamped tight in the vise) before turning the machine on
  • you MUST NOT let the blade touch the workpiece before it has reached the appropriate speed
small splinters can fly towards the operator wear goggles
chips created by the machine can be sharp you MUST NOT remove chips by hand. Use a chip hook or a brush instead
hardened steel may break the blade you MUST NOT attempt to cut hardened steel. If you are uncertain, test whether a file can bite into the material (=non-hardened)
the motor may overheat when it is stalled or the saw head is hindered from going through the entire cut (e.g. by obstacles or a dull blade)
  • you MUST supervise the machine during the cut
  • turn off the motor in case of unusual noise, erratic behavior of the blade or a lack of downward movement regardless of the spring setting and take time to find the problem before re-attempting the cut
Danger - sudden start.svg
no prevention of turning on after loss & restoration of power (keine Anlaufsicherung)
if the power has been lost for whatever reason, always turn the switch "off" before restoring it!

Suggested Reading

Besides these safety notes, you should know about the different types of bandsaw blades in order to pick the proper one for your project.

Proper speed (and thereby feedrate) calculation can be a science in itself, but leads to the best cut quality and optimal efficieny. Here are some resources to get started (1 fpm is about 0.3 m/min):

Other useful links:

Demonstration

The tutor will show you the following in detail:

  • check proper adjustment of the blade with the bandsaw jig
    • if adjustments are necessary, refer to the corresponding section on the machine page - if anything is unclear, ask a tutor for help before you change anything!
  • belt-based speed selection
    • rule of thumb: softer/thinner workpiece = faster, harder/thicker workpiece = slower
    • common material/speed combinations: up to 90 m/min for soft metals like aluminum, copper and brass; 30-90 m/min for steel depending on thickness; 10-30 m/min for stainless steel [1]
    • for best results, see #Suggested Reading to go beyond rules of thumb and really start calculating ;-)
  • Securing the workpiece on the machine
    • adjust upper guide to just clear workpiece
    • make sure the vice doesn't hit any part of the moving bandsaw, otherwise it won't complete the cut
    • if possible, position the workpiece in a way that reduces "flat" sections that are parallel to the blade (e.g., an angle iron cuts much better as a Λ than an L) [2]
  • adjust the downward force
    • start with a "floating" saw and slowly release spring tension during the cut until you see nice chips (use just as much force as necessary!)
  • Turn on the machine
  • Turn the machine off after usage or in case something goes wrong
  • Clean up
    • remember to return the machine to townward position so there is no risk of tipping it over!
    • when moving the saw make sure to hold both the upper and lower parts or it might tip over.

Waiting List

This introduction takes longer than many others and usually can't be done spontaneously during regular opening times. If you would like to receive it, please add yourself to >> this list << and we will find a good time once a few members are on it!