Club Meeting: 8 May 2019
Report By: John Whitmore

The intention was to both inform members and to preserve the Guild’s tools. Consistent sharpening of SAWG tools makes it easier for new turners to move between work stations and the tools last longer. Instruction is available for using the sharpening station.

Tools can be sharpened on either an abrasive wheel or on a flat abrasive surface such as a disc or linisher (a belt sander in disguise). Whilst all have their merits, the basic difference is that wheels produce a concave bevel and discs/linishers give a flat bevel. Honing was not part of this presentation but could usefully be incorporated in a later demonstration.

The usual form of abrasive wheel sharpening is via a double-ended grinder having wheels of 150mm (6”) or 200mm (8”) diameter, the larger size being preferable but more expensive. More specialised machines are available including several brands with larger 250mm (10”) wheels running in a water bath and slower speed grinders intended to reduce the generation of heat.

Ordinary ‘workshop’ grinders are usually supplied with (grey) carborundum wheels of low quality. Internationally, there is a variety of different coloured grinding wheels purporting to serve different purposes but the ideal approach is to have a cubic boron nitride (CBN) wheel for high speed steel (HSS) tools at one end, plus an aluminium oxide wheel (white) for other ferrous materials, at the other end. Both are readily available in NZ.

The use of a 300mm disc sander for sharpening was developed in-house and with a jig for each tool, enables a quick ‘polish’ rather than serious grinding to replenish an edge. The linisher is a much more expensive product by Robert Sorby having a useful variety of easily interchangeable belts and reliable jig settings for repeatability. Whereas all grinding wheels (except the CBN) gradually reduce in diameter, the disc and belt abrasive surfaces remain consistently flat.

Other useful points arising were:

• Recommended bevel angles for Guild tools are bowl gouges of 35 and 55 degrees, spindle gouges 30, spindle roughing gouges 45, parting chisels 30, skew chisels 30.
• Wheels, disc and linisher abrasives have different grits (or roughness) and hardness.
• Don’t dip HSS tools in cooling water as the temper will be ruined. Tool steel is OK for cooling.
• Always use a jig to achieve a single, smooth, and symmetrical bevel. This doesn’t work well for negative rake scrapers or if an asymmetrical bevel is wanted – the latter usually by professionals freehand sharpening.
• Putting a diamond-section parting tool sideways into the Guild’s Truegrind tool holder enables both bevels to be sharpened without any repositioning.
• A diamond dresser is available for cleaning dirt and glaze off all sintered (cooked in an oven) wheels. A CBN wheel is never dressed.
• Sintered wheels can shatter so always use them with guards in place.
• Do not sharpen on the side of a wheel unless specifically labelled as a side-cutting wheel.
• A 55 degree bowl gouge is useful across the inside bottom of bowls when a more ‘pointy’ 35 degree grind may result in a gouge shaft hitting the bowl rim.
• Sharpening a pencil is a good analogy to explain ‘cutting with the grain’.
• A plug was also given for using sharp sandpaper.

Alongside the theory, sharpening using Guild jigs and tools was demonstrated with some bowl shaping. The presentation was accompanied by excellent visual aids and invasive music from next door. Despite the music, a good time was had by all and clear information was received during a well-structured performance.

Date: 27th March 2019
Report by: Bruce Wiseman

An ingenious piece of mechanism individually made by Holm Miehlbradt.

TOTAL STORY !! — You had to be here to understand what was being demonstrated.
See if you can work it out from the photos taken by Ross Johnson.

This was an unexpected demonstration of an engineer’s determination to make a complicated piece of design concept to produce a machine that will produce repetitive patterns of a circular character on wood, plastic, or other similar substances.

Holm using MDF for the main frame and lathe head, a compound slide to carry the tool holder and cutter head, together with a powerful electric spindle motor and sundry pulleys, sheaves and rubber band type drive belts created this amazing piece of wizardry known as a Rose Engine.

With the lathe head rocking back and forward to the pattern of the Rosette pattern and the cutter driven by the spindle motor, all controlled by a pair of hand wheels, the product was produced.

Comment:- You need to have a lot of time to make and use a ROSE ENGINE.
Well done Holm!

Additional link for more information on how to build a rose engine http://www.whidbeyworks.com/root/Home.html

Demonstration Date: 20 March 2019
Demonstrator: Trefor Roberts
Author of Article: Wim Nijmeijer

As Vice President of the NAW, Trefor started by telling us about the work of the NAW and the benefits of becoming a member.

He then started by telling us that form is paramount in woodturning. Without a good form, the end result will always be compromised.
First review your finished turning and determine if embellishment is needed. (Spalted/figured wood, natural edge generally do not need embellishment) To enhance your woodturnings, various techniques of embellishment can be applied. Ideas can be found everywhere, nature, Internet; take pictures such as the Koru, Ferns, Butterflies, etc.

Trefor then proceeded by showing us a picture of a printed leave (laser print) and how this image was transferred onto the wood. First cut out the leave, and then apply Minwax Polycrylic (can be obtained from Mitre 10) to the wood and stick the printed leaf (ink facing wood) firmly onto the wood. Let it dry, once dry, wet the paper leaf with water and gently rub the paper away. The leaf image has now been transferred onto the wood. Various examples were shown of images transferred onto wood, these images could then be permanently marked by using pyrography or carving (Dremel, etc)

Next Trefor showed us some examples of engraving (smoking!) by using a Dremel and a ball shaped burr, to produce/burn indentations of half spheres, followed by wire brushing to remove the carbon.
This was followed by showing us half a dozen of turned eggs. These were already embellished/painted with various patterns/colours. One egg was then further enhanced by using various colours of Guiders Paste.

Next Trefor used some Milk Paint (can be made by mixing 1 part water to 3 parts powdered milk until you get something around the consistency of paint. Blend in a water-based coloured Dyes or foodcolouring if you don’t want neutral white)
Various combinations of using milk paint mixed with coloured dyes, acrylic paint and Guilders Paste were demonstrated.

This was followed by a demonstration using the Burnmaster by burning some patterns on a practice piece.
Last but not least Trefor used the Dremel fitted with a half-cup burr, this was then used to burn perfect half spheres onto the wood.

All in all a well executed and very interesting demo. Thank you Trefor.
Trefor’s last message for the evening: I hope you enjoyed the demo, and make sure you become a member of the NAW!