Difference between revisions of "Woodturning Introduction"

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(extra skew chisel practice should be included every time)
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* cutting "downhill" when sculpting features on spindles
 
* cutting "downhill" when sculpting features on spindles
  
== Waiting List ==
+
{{Waiting List}}
This introduction takes longer than many others and can't just be done during regular opening times. If you would like to receive it, please enter yourself '''[[Woodturning Introduction/Waiting|>>here<<]]''' and we will find a good time once a few members are on the list!
 
  
  
 
[[Category:Introductions]]
 
[[Category:Introductions]]

Latest revision as of 17:16, 12 September 2019

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

Let's begin! First off, make sure you have read the machine's manual and have watched at least one of these videos explaining how catches ("Nürnberger") happen:


Safety

Dangers

  • quickly spinning exposed chuck and workpiece
    • workpiece might fly at you if it gets loose
    • danger of entanglement (Einzugsgefahr)
  • tools, especially skew chisels, can get caught on the workpiece's surface (leading to a catch or runback) ==> see videos linked above!
  • parting tools can get stuck in the cut due to the high friction
  • flying shavings, splinters and dust
  • belt-based speed selection

Precautions

  • unplug the machine before opening the belt housing to select a different speed
  • start at the slowest motor speed, increase when the workpiece is rounder [1]
  • tool rest
    • should be set very close (1-2 mm) to the workpiece, adjust it after removing material [2]
    • always let the tool touch the tool rest before the workpiece
    • make sure the tool is supported on the side you're going to cut with
    • treat the tool rest like a barrier: never reach across it with your fingers "or any other part of your anatomy you want to keep" [3] while the lathe is running!
  • always make sure all screws and nuts (tool rest, tailstock, spindle) are properly tightened
  • give the workpiece a test spin by hand to check whether it catches on anything before turning on the motor
  • practice far in the middle of your workpiece and stay at least a tool's width away from the lathe's metal parts (centers, chuck) until you can control the tools without runback
  • proceed slowly and smoothly "into" the workpiece - you want to shave material off, not break it!

Suggested Reading

Besides these safety notes, you should read our page on woodturning tools.

You really should! Damaged tools are your responsibility to replace and can get quite expensive...

abused & bent tools - not cool!


Demonstration

The tutor will show you these steps in detail:

  • speed selection
    • unplug the lathe
    • open the belt housing on the left
    • loosen the red screws holding the motor in place (just a little bit, do NOT remove them!)
    • lift the motor up to get some slack in the belt
    • switch the belt to the desired setup (same position on both pulleys!)
    • let the motor go back into its original position and re-tighten the holding screws
    • leave the belt a bit looser than you would on the drill press - that way, it can slip when an accident happens!
  • setting up a workpiece between centers ("spindle work")
    • find the center point and mark it on both sides
    • remove the drive center from the headstock, set it on the center point you marked on your workpiece, and hammer it "in"
    • in case of hardwood, a few relief cuts across the center point may prevent splitting
      • this may also reduce the need for hammering the drive center into the workpiece
    • screw the drive center back onto the headstock spindle and move the tailstock as close as the workpiece allows
    • drive the tailstock spindle into the workpiece and secure it with the nuts on either side of the tailstock
  • letting the bevel of a gouge "ride" on the workpiece before the cut
  • cutting a shaving with the skew chisel: let the bevel ride and keep the contact point with 1/3 of the blade below and 2/3 above (should already work if the workpiece is rotated by hand, otherwise something is wrong!)
  • cutting "downhill" when sculpting features on spindles

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!