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Northumbrian Woodturners Weekly Bulletin No13
Northumbrian Woodturners Association continues to offer sincere thanks to all at the NHS and to all those other services and individuals who are helping at this time of National crisis. Our condolences to all those who have lost loved ones and to families of those who have given their lives whilst caring for others
Test ~Your wits Today 1. How many teeth does an adult human have?
2. What is the largest bird of prey in the world?
3. In which sport would you use a shuttlecock?
4. Who is fifth in line to the British throne?
5. What is the biggest state in America?
6. Who wrote Snow White And The Seven Dwarves?
7. What is the capital of Hawaii?
8. Enchiladas originated in which country?
9. In Dirty Dancing, what is Baby's first name?
10. How many eggs does the average chicken lay per year?
11. In which English seaside town was ‘Fawlty Towers’ set?
12. What is a group of lions called?
13. Where would you find the River Thames?
14. What animal alive today is even bigger than a dinosaur?
15. What alcohol do you traditionally use to flame a Christmas pudding?
16. What is a baby kangaroo called?
17. What is the name of the fictional town where the series Stranger Things is set?
18. What year did Rihanna achieve global success with the mega-hit 'Umbrella'?
19. Name the slowest animal in the world.
20. Is the sun a star or a planet?
21. What are the names of Harry Potter’s parents?
22. What is the capital city of Spain?
23. Who plays Tommy Shelby in Peaky Blinders?
24. How many legs does a lobster have?
25. How many Michelin stars does Restaurant Gordon Ramsay in London currently hold?
26. What's the best selling book of all time?
27. In which English county is the town of Stevenage?
28. Botany is the study of what?
29. To the tip - how tall is the Eiffel Tower?
30. Sofia is the capital of which country?
31. What is the name of James Corden's character in Gavin & Stacey?
32. Who famously said "You must be the change you wish to see in the world."
33. Which is the only venomous snake native to the UK?
34. Arctic Monkeys took the indie scene by storm in 2005 with the now classic 'I Bet You Look Good on the Dancefloor' - but what's the first line of the song?
35. What planet is known as the red planet?
36. What is the name of the Greek dip consisting of yoghurt and cucumber?
37. Catalonia is a region of what country?
38. Who wrote Oliver Twist?
39. What colour is a giraffe's tongue?
40. What do you call a group of jellyfish?
Our Very own Helen Bailey is to Host a Zoom session 7pm on Monday, the last one was a good watch – Kevin showing us what he does in his workshop
Joint Northumbria – Borders and Wear Valley Club Meeting online using Zoom
Last Monday in a moment of weakness, or possibly due to the red wine, Kevin McAlister had volunteered himself to introduce us to the wonders of Powertex.
I think it's safe to say the audience had no idea what was coming as Kevin introduced some of his work and then proceeded to show us how the stunning effects are achieved.
The techniques involve preparation of a recess in the piece of work and then addition of fabric or, other materials, which are coated in Powertex.
However, this was only the start of Kevin's exploration of using this material and several of the others in the Powertex product range.
At least one member of the audience is going to be receiving a delivery of Powertex within the next few days and we can look forward to some pieces featuring these and other techniques.
Zoom is available FREE OF CHARGE from the Zoom website. Lots of information on using this is available on the Borders Website. If anyone has any Questions Kevin Can be contacted by Email: [email protected] For those of you using Instagram he can be followed: kmc_woodturner
A good night was had by all and we have a willing (well almost willing) volunteer for next weeks session which will feature Helen Bailey
Thanks once again to all involved and remember it's much better to volunteer rather than wait to be press-ganged into it!!
FREE MAHOGANY!! Brian Archer has been given some lengths of mahogany 6 inches by 2 inches and has some spare lengths to pass on to anyone who wants them. One is 43 inches long and the other is 48 inches long. They are rough cut on the outside but fine inside. If any member wants either or both lengths, they should contact Brian on 0191 2685387 or by email on [email protected] and he will arrange for a no contact handover.
Plant Stand
By Ian Elliott
I have not been doing any turning this week, as I have been making a
freestanding plant stand for our back garden. Our back garden faces north so we
do not get much sun, we planted gravel several years ago as nothing would
grow.
We are still socially isolating, so decided we would like to grow some salad, herbs
and a few flowers. I ordered treated softwood, which was delivered on Tuesday
morning. I had already made a sketch of what we wanted so started straight
away. I just finished before the rain came down (Thursday afternoon). I have no
idea how many screws I have used, but it is well into the hundreds, big thank
you to the people who came up with the idea of a battery screwdriver.
I have now got to fill all the troughs job for tomorrow if the rain keeps off, plants
and seeds are on order. I know its probably a bit late, but we just came up with
the idea.
Hope you are all Safe and Well
Ian Elliott
Michael Johns was inspired by the work of Pat Carroll to have a go at a 300mm tall 125mm diameter form made from sycamore pierced and then pyrographed then painted with reactive rust paint.
Kevin Purdy and Arthur Cornell have both been making tall elegant hollow forms. Arthur’s is in Green stained ash
Kevin’s is also ash, stained with red and black Morrell’s stain and silver gilt cream. The base and finial are sycamore and black embellishing spray.
Billy Brown meanwhile has been making four candlesticks. No, nothing to do with handles for forks.
Below and on the next page is more of Billy’s work.
Frank Bowman has made some fine open segmented pieces, an open segment
bowl 5”x 10” and an open segment vase 7” x 9”
Unusual use for a woodturning lathe By John Christie
How to split a coconut to make a musical instrument (horse clip -clop). Set nut up between centres (protect bed from stray juices!) spin up to 1000 rpm
Apply parting tool till through to flesh remove from centres, drain & split, scoop out the flesh. BINGO!
Drilling Pen Blanks on the Lathe
By Walter Hall
The purpose of this short tutorial is to help less experienced pen turners to learn how to use a wood
turning lathe to safely drill clean accurate holes through wooden or acrylic pen blanks.
The methods used and opinions expressed are primarily my own, but I have tried, as far as possible,
to include methods preferred by others in order to be as inclusive as possible.
Tools and Equipment needed
A means of holding the blank in the headstock. Options include a dedicated pen blank drilling chuck;
pen blank jaws fitted to a scroll chuck; pin jaws fitted to a scroll chuck. Any of these will work just
fine but my preferred option is that of pen blank jaws fitted to a scroll chuck as I consider these to
give the strongest hold on the work piece.
A chuck to hold the drill bits in the tailstock. Jacob’s chucks, keyless chucks and collet chucks are all
suitable. Apart from the convenience of tool-less bit changing afforded by keyless chucks I do not
think there is much to choose between these options. A chuck with a drawbar fitted will prevent the
risk of the chuck becoming detached from the tailstock (see Health and Safety below) but this is not
essential if good practice is followed and is not possible with lathes that do not have a hollow
tailstock.
Drill bits. Standard “jobber” twist drills are cheap as chips and will do the job. The centre point of lip
and spur or dowel bits make it easier to centre the bit on the work. Better still in my opinion are
bullet point bits which centre even more easily. Dedicated “pen drill bits” are available and I find
these work well too but some turners find that the thinner sizes tend to have too much flex in them
and consider them inaccurate. The manufacturers claim that these can be run at high speeds and
drill in one pass. I find these claims to be a little exaggerated. (If you look carefully at their own
promotional video you will see a wooden pen blank burst out at the side as it is drilled) The flutes do
clear more readily than standard drills and they are very useful for drilling long blanks but don’t
expect miracles. Some turners like to make a starter hole with an engineers’ centre bit to ensure the
drill bit is centred others say this doesn’t make a blind bit of difference. I have no strong opinion
because I use the bullet point bits which centre themselves.
Health and Safety
The biggest health and safety problem arises if the drill bit jams in the work and the tailstock is then
withdrawn far enough for centrifugal force to snap the drill bit or cause it to break out from the
work and hurl the chuck off the lathe. Working in the ways described here will prevent that.
There is also a small of risk of injury caused by holding on to the chuck whilst drilling. Again, by
working carefully and following the guidance in this tutorial this risk can be minimised.
All of the other H&S advice for lathe work needs to be followed. Eye protection or better still full
face protection is essential. Respiratory protection advisable with some timbers. No loose clothing or
jewellery, long hair tied back, don’t wear gloves etc. etc. Read the lathe instructions.
Methods of operation
Mount your preferred chuck onto the headstock spindle ensuring it is tightly secured. Mount the pen
blank in the chuck and ensure that it is tightly secured and running true.
Ensure that the tailstock Morse taper and the Morse taper of the tailstock chuck are both clean and
free from grease or other contaminants then mount the chuck securely in the tailstock. If your lathe
has a self-ejecting taper make sure the quill is not wound too far back as this will prevent the Morse
taper from seating properly. Once properly seated in the Morse taper it should not be possible to
turn the chuck by hand or pull it out of the tailstock. Select the appropriate size of bit and secure this
in the tailstock chuck ensuring it is centred in the jaws and the chuck fully tightened. For larger sizes
some turners prefer to drill a pilot hole with a smaller bit first.
Select the most appropriate spindle speed for the material you are drilling and turn on the lathe. I
find that 300 to 500 rpm will suit most timber and acrylic blanks. Too slow a speed and centring the
bit at the start of the cut will be difficult, too fast and the bit and work piece will both overheat. This
is one of the main causes of jammed bits and can also cause irreparable damage to both drill bit and
blank. Timbers with pronounced grain patterns typically don't have homogenous hardness - there
are hardness variations between portions of the wood that grew during warm weather, and the
portions that grew during colder weather. And if the drill bit is advanced into the blank too quickly, it
will tend to follow the grain pattern staying in the softer wood. So it is critical that the tailstock quill
is advanced slowly so that the point of the drill can actually cut a straight hole for the drill to follow.
Bring up the tailstock until the point of the drill bit is a few millimetres away from the end of the
revolving blank and lock the tailstock to the bed. Check to ensure that the point of the drill is centred
on the blank and you are ready to begin drilling.
Note: Some turners like to hold on to the chuck whilst drilling, however, in my opinion, holding onto
the chuck whilst drilling serves no purpose and here is why I believe this.
If the Morse taper is properly seated in the tailstock I can neither turn it by hand nor pull it out. Thus
the friction between the chuck and tailstock is greater than the torque I can apply by hand. If the bit
jams and starts to turn the chuck then the torque applied by the lathe turning the jammed bit must
be greater than the friction between the chuck and tailstock. It therefore necessarily follows that the
torque applied by the lathe is also greater than the torque I can apply by hand. Thus holding on to
the chuck is not going to stop it from turning. For this reason and because of the slight risk of injury I
do not recommend to beginners holding on to the chuck whilst drilling and if you choose to do so
then be careful to use a grip that can be easily and quickly released.
Once drilling has stopped and the bit is being withdrawn either to clear the flutes or at the end of the
job and the lathe is still running, holding the chuck lightly once the bit is disengaged from cutting in
case it catches in the hole and is pulled out of the tailstock is in my opinion perfectly safe and
sensible.
Photo © Doug Barratt
Begin drilling by winding in the tailstock using the hand wheel. After a few turns of the wheel wind
the bit back out again to clear swarf and chips from the flutes of the bit. Failure to do this is the
second most likely cause of jammed bits after excessive speed. Allowing swarf to accumulate in the
flutes of the bit increases the friction that causes heat. But the nature of the timber has a role here -
the swarf from oily woods such as cocobolo will clump into a hard mass in the drill bit flutes far more
rapidly than will be the case from dry, brittle woods. As a result, the more oily the wood, the less
depth one can drill without clearing the swarf. With extremely oily woods (or if a lubricant us used
when drilling), it may be necessary to pick the hardened swarf out of the flutes with an awl.
As noted above, holding the chuck lightly once the bit is disengaged from cutting in case it catches in
the hole and is pulled out of the tailstock is in my opinion perfectly safe and sensible. If your tailstock
has a self-ejecting taper take care not to wind the quill so far back that the chuck is ejected from the
taper.
Repeat this process until the blank is drilled completely through. With acrylic blanks, even with
careful drilling you may get breakout or splitting when the bit exits the blank. This can be avoided by
leaving the blank over long and drilling just short of breakthrough then sawing the blank to length
after drilling. To facilitate this you will need to mark the depth of cut required on the drill bit with
masking tape.
When boring long blanks that exceed the length of movement of the tailstock quill it may be
necessary to reposition the tailstock closer to the work part way through the process. It is safest to
switch off the lathe to do this.
Once the drilling is completed, with the lathe still running, withdraw the bit completely from the
blank by winding back the tailstock quill, at the bit is withdrawn you should lightly hold onto the
chuck to prevent it from being pulled out of the tailstock. If the tailstock was moved closer to the
work as described above then it will be necessary to slide the tailstock back to completely withdraw
the bit.
All photographs © Walter Hall except where otherwise indicated.