Woodturning/Printable version

From Wikibooks, open books for an open world
Jump to navigation Jump to search


Woodturning

The current, editable version of this book is available in Wikibooks, the open-content textbooks collection, at
https://en.wikibooks.org/wiki/Woodturning

Permission is granted to copy, distribute, and/or modify this document under the terms of the Creative Commons Attribution-ShareAlike 3.0 License.

Lathes

A woodturning lathe is a machine which rotates a piece of wood while a cutting tool shapes the wood.]


Tools

Skew chisel[edit | edit source]

The traditional skew chisel is made from a rectangular bar, but more recently it has become available in 'oval' and round cross-sections. The cutting edge is usually straight, but some turners prefer a convex edge. The skew chisel is used primarily in spindle turning.

There are three distinct ways to cut with the skew chisel.

  • Cut with the long point - normally used for making V cuts and cutting across end grain.
  • Cut with the edge - used for making planing cuts and beads.
  • Cut with the short point - an alternative method of cutting beads.

Spindle Gouge[edit | edit source]

The spindle gouge and its variant the detail gouge is used mainly for spindle turning, but also for detail work in faceplate turning and shallow bowl turning. The modern spindle gouge is usually made from a round bar of high speed steel that has a wide and shallow flute ground or milled into it. They are available in a variety of sizes up to about 1/2".

Some manufacturers make a detail gouge which is a spindle gouge with a shallower flute, more able to reach well beyond the toolrest.

Traditionally the spindle gouge was forged from a flat bar of carbon steel.

The spindle gouge looks similar to a bowl gouge and should not be confused. The flutes are not as deep and the steel is usually not as thick as a bowl gouge.

The spindle gouge has many applications:

  • cutting coves in spindle work.
  • cutting beads in both spindle work and face work.
  • hollowing end-grain.
  • making fine cuts in face work.


Safety

The process of woodturning is not without its dangers. Some are fairly obvious, some less so. Some may result in short term minor injuries, some may be much more serious, and others may cause long-term health problems that may not be apparent for many years.

The purpose of this chapter is to highlight these dangers and make recommendations to minimize or remove the risk. Ultimately, safety is the individual's responsiblity and will depend largely on both their knowledge and attitude. If in doubt seek proper training or advice.


  • As with any rotating machinery, the operator must take care not to let their clothing, hair or jewelry get caught by the machine or wood.
  • Work pieces must be securely attached to the lathe before turning it on.
  • Make sure that the workpiece can be fully rotated without hitting the lathe bed, toolrest, banjo or other objects around the lathe.
  • Workpieces must be of sound material that will not break while being shaped. Wearing a face mask is recommended.
  • Tools must be supported by the toolrest before contacting the wood.
  • Beware of turning wood which is not perfectly round. Irregular edges turn to a nearly invisible blur when spinning. Examples include work not yet roughed down to a round, or natural edge. Some chucks may pose a similar hazard.
  • Wood dust of any type can cause problems with the respiratory system, skin or eyes. Some woods are toxic and present even worse hazards. Dust extraction and dust masks or respirators are recommended.
  • Many finishes use solvents that are dangerous, either through skin contact or inhalation of fumes.
  • Many finishes cure by polymerisation which is an exothermic chemical reaction. Rags used for applying these finishes should be disposed of so they cannot spontaneously combust and cause a fire.


Anchor, Bevel, Cut

Anchor, bevel, cut, or ABC, is a procedure taught to woodturning novices as the only safe method of starting a cut.

Anchor[edit | edit source]

The first thing that the tool should contact is the toolrest. It needs to be firmly anchored there using one hand.

The consequence of letting the tool touch the spinning wood before it is supported by the toolrest are that it will slam down onto the toolrest, possibly breaking the tool, possibly breaking any fingers trapped between the two, or wrenching the tool out of the turners hand.

Bevel[edit | edit source]

The heel of the bevel is then brought into contact with the wood. It provides support and direction for the cutting edge.

The consequence of beginning the cut without bevel contact is likely to be a catch (the tool violently digs into the wood) or the cutting edge is forced to run back along the wood cutting a spiral groove as it goes.

There are some cuts (such as starting a V-groove with a skew chisel, or cutting into the rim of a bowl) where bevel support cannot be used. In these instances the turner should plan to take a very light cut, be sure to align the bevel with the direction the cut is to take, and proceed with caution.

Cut[edit | edit source]

With the tool on the toolrest and the bevel supported on the wood, the angle of the tool is adjusted slightly until a cut is engaged. The tool can then be moved forward gently and evenly to make the cut. While the cut is proceeding the operator should switch from looking at the tool to ensure the tool is engaged properly to the horizon of the wood as the cut proceeds. The line, form and shape are easily discernible by looking at the horizon and as changes in line and form occur there is a constant feedback/feedforward between what the operator sees and the muscular responses required to get the exact shape needed.

Mastering the process[edit | edit source]

It sounds complicated, but once practiced it very soon becomes second nature. However, it only takes a moment of inattention for an accident to happen.


Natural edge bowls

File:Natural-edge-bowl.JPG
This birch bowl has a natural edge. In the foreground the bark has been compressed by a limb growing out of the tree.

Natural edge bowls, also known as live edge bowls or wany edge bowls retain the original surface of the tree trunk as the rim of the bowl. The term live edge is only applicable where the bark has been retained.


Cutting logs for bowl turning

WARNING - Chainsaws are extremely dangerous. Be sure to read, understand and carry out the safety instructions that come with your saw.

Most large bowls are made from logs. The pith will almost certainly crack as the wood dries, so it is usually not included in bowls that are intended for functional use. This article suggests ways to cut large logs into bowl blanks ready to go on the lathe.

Approach 1[edit | edit source]

In this method, two bowl blanks are cut from one short section of a log.

A flat is cut either side of the log to show mark lines better and to stabilize the block during sawing. The lines are laid out carefully to ensure that blocks of uniform thickness are made from the center section. A piece of card is used to mark the lines parallel to the floor. If the log is tapered, consider wedging-up the narrow end to keep the pith in the center of the waste block and away from the bowl blanks.

A chainsaw is used to cut the block. First, shallow cuts are made straight along the marked lines. These then help guide the saw as deeper diagonal cuts are made. [note 1]

The piece of wood in the middle that contains the pith will be cut up and used for smaller projects. The pith will be cut out and discarded, since it is certain to split, leaving two blocks that will make small bowls or be cut up further for spindle turning.

The cardboard templates are used to mark the circumference of the bowls on the log halves. The chainsaw is used to cut off the corners and excess material before the blank is mounted on the lathe. This makes the block of wood more balanced so the lathe can run faster, which can save a lot of time.

Approach 2[edit | edit source]

A bandsaw mill is used to cut whole logs into big thick slabs. Again, the wood containing the pith is cut up into boards a couple of inches thick, and the pith discarded.

The advantage of this technique is that it saves having to make ripping cuts with the chainsaw, which is hard work for both the saw and the operator.

Notes[edit | edit source]

  1. Most chainsaws are sharpened for cutting across the grain, i.e. straight through the trunk. Cuts across endgrain produce nothing but dust and the saw tends to kick and buck. Cuts along the grain produce big long shaving that tend to clog the saw. To slab-up a log as shown here, it is best to cut on a diagonal whenever possible, somewhere between these two extremes.


Copy turning

Copy turning is carried out on special lathes that control the cutting tool in some manner to produce identical items.

The copy lathe uses a template to guide the cutter. They are capable of creating good quality components for little expense in patterns and setting up. Sanding is usually carried out by hand.

Fully automatic lathes may use rotary tooling, profile tools, or CNC driven cutters to produce the shape. They are capable of producing work quickly and to a good quality finish, but these machines usually rely on machine sanding which will not always retain fine detail. They require special tooling and considerable set up for each job.


Salt and Pepper Shakers

Finished salt and pepper shakers

SALT AND PEPPER SHAKERS

Start with a blank approx 210mm by 70mm

Make a marking stick (template) for your design


BLANK

1. Turn to round

2. Mark the division between top and bottom with template

3. Part in ~ 50% of the way

4. Cut a spigot on top and bottom for re-mounting


5. Divide the work on the bandsaw or with a handsaw

UPPER HALF

6. Mount the top section first

7. Square off the end and then round the blank to approx 55mm

8. Mark the top point (nearest the headstock) with the template and part in

9. Drill in with 1&1/8th inch forstner bit to no more than 5mm of top

10. Now open the hole with a parting tool by approximately 6mm width (or half the dimension of the wall and 10mm deep. Gauge and set the depth with the depth gauge. NB. If the join is deeper the total height of the work is correspondingly smaller

11. Part off, leaving a ‘nub’ for the tailstock on re-mount of the whole

BOTTOM HALF

12. Square the end and round the blank to approx 55mm

13. Drill in with forstner bit to within 10mm of the base

14. Mark the base of the tenon with the depth gauge (refer step 10) 1-2mm shorter so that the join is seamless

15. Part in and form the tenon carefully so the top is a comfortable jam fit. NB. Don't force a tight fit as the top will split

JOIN THE WORK

16. With the components together, bring up the tailstock and round the entire work to finished dimension of 50mm

17. Sand through grades to 400

18. Mark the details with template

19. Check the bottom dimension against the paired unit before parting in

20. Cut the beads and round the top

21. Sand the details to 400

22. Remove the tailstock and carefully finish the top with the skew chisel

23. Using the index wheel, mark the top with Awl for Salt or Pepper Salt: Center ~ 2.5mm Stops 8, 16, 24 ~ 2.5mm Pepper: Center ~ 2.5mm Stops, 4, 8, 12, 16, 20, 24 – 1.5mm

FINISH THE BASE

24. Mount the base on a custom mandrel and drill through with 5/8th inch forstner bit, or one that suits the plug you are using.

25. Dish the base as necessary to suit the plug


Woodturning organisations

Woodturners in many countries have formed organizations for the purposes of education and promotion. This page lists those organizations by country. Only nationwide organizations are listed here; their websites usually list regional chapeters.

Australia[edit | edit source]

Canada[edit | edit source]

New Zealand[edit | edit source]

United Kingdom[edit | edit source]

  • Association of Woodturners of Great Britain [1] - dedicated to the advancement and promotion of woodturning,
  • British Wood Turners Association [2] - represents the British wood turning industry and promotes the continuing craftsmanship and skill of its members.
  • UK Register of Professional Turners [3] - supported by The Worshipful Company of Turners of London, the register is composed of turners who offer a professional service to the public.

United States of America[edit | edit source]


How to help write this book

Anyone can contribute to this Wikibook about woodturning. If you have any expertise in any aspect of woodturning, please contribute articles, correct mistakes, edit for clarity and accuracy, expand articles or contribute photographs.

Before you start, please familiarize yourself with the markup code used for editing, along with Wiki etiquette, policies and guidelines.

Some good places to start learning about Wikibooks are Wikibooks:Welcome, newcomers and Help:Wikibooks.

When editing, please be sure to preview your work and fill in the Summary of the changes you are making before saving.

All articles must be written from a neutral point of view. If you wish to discuss the contents of a "subject" page, click on the "Discuss this page" link to get to the talk page. All content, both text and images, must not infringe the copyrights of other parties.


Contributors

Derek Andrews[edit | edit source]

I am a full time professional woodturner based in Nova Scotia. I started this Wikibook on January 8, 2006, then forgot all about it for a year or more. I can be contacted at User talk:Derek Andrews