BOO-HOO!! My bowl split!!

[adrian]

My neighbour cut down a small eucalypt (200mm diam) and the trunks have been laying around for about 3 months. I cut it into 200mm long chunks and turned one of them into a bowl. It ended up looking quite good for a first attempt.
Got up this morning to find a 4mm vertical split in it.
The split starts at the end of a sap trench. Is it just a case of 'welcome to the wonderful world of turning' or is there something I can do to decrease the chance of this happening?
I turned the bowl in the endgrain. I take it that this the accepted practice?
I have seen pictures of many turned objects that have sap pockets incorporated into the design. Is it the age of the blank or the type of wood that makes this possilble?

[macca2]

I am by no means an expert. Only been turning about 3 years and have produced large amounts of decorative fire wood but I don't think you should turn a bowl in end grain. Also the wood may be a little green.
Keep going because it is a bundle of fun learning about the wonders of wood when attacked with a chunk of steel while spinning at high speed in alathe.


Macca

[RETIRED]

Gooday.

At the risk of offending you Adrian but perhaps saving your skin I offer this bit of advise.

Get lessons or join a club, read books on turning and practise, practise and practise.

Except in very rare circumstances and some small boxes YOU DO NOT TURN END GRAIN.

[Kev Y.]

adrian, What said.. also I think that 3 months may not have been enough time for the timber to dry. you could always turn the bowl down to a wall thickness to an inch (25 mm) or so, then microwave the bowl to dry it out , then re-chuck it and finish it off.

Microwaving is another totally different thread topic.!!!!!

Kev

[adrian]

No offence taken . When seeking advice I can never take offence when I get it.
All of you city slickers are lucky in that you have access to clubs and night schools for all sorts of things. It's not so easy to find that sort of thing in the country. I have been buying books and have a subscription to Australian Woodworking which has a lot of turning content.
Regarding your advice, "you do not turn endgrain", I have a woodturning book by Phil Irons which has a project titled End Grain Hollow Form which shows "how to turn a hollow form in wet wood so that it doesn't split."
I think my confusion arises because when you turn something like a goblet with a long narrow stem, the grain must run parallel along the blank otherwise the stem would be very brittle. This also means that your chisel would be cutting into endgrain in order to hollow the cup. Does your advice about not turning endgrain relate more to shallow bowls/plates and spindles.

[Cliff Rogers]

.... I have a woodturning book by Phil Irons which has a project titled End Grain Hollow Form which shows "how to turn a hollow form in wet wood so that it doesn't split.".....

G'day.

Does he say what sort of tree he's using?

I'll bet you that it isn't a eucalypt.

With a few notable exceptions, eucalypts don't suit anything that is hollowed out, end grain or other wise...
The notable exceptions are burls & red gum.

Most Australian dry country timber 'tends' to crack radially so as a general rule, I split it into billets lenghtwise through the heart & use the billets for turning between centres IE: spindle turned tool handles, cheese knife handles, candle sticks, bud vases, salt & pepper shakers/grinders, pen blanks etc.

This is a generalisation for beginners. There are pros out there that do marvelous work with some species of inland timbers to produce hollow forms & natural edged bowls & vases but they've been messing with it for ages & they already know what works & what doesn't.

Too avoid disappointment while you are still a beginner, stick to the generalisation.

If you really want to have a go at bowls & hollow forms, see if you can score some timber out of a fruit tree that's being cut back/removed. Be aware that Citrus tends to split like the eucalypt. Good ones are mango, lychee & mulberry. Also keep an eye out for some Camphour Laurel or even a hunk of Jacaranda. The Jacaranda is dead boring looking stuff but good for learners to practise on & if you do turn out a 'masterpiece' you can decorate it by pyrography or painting.

When you get better & score a 'special' piece of timber that looks like it's going to crack, you can stablise the area with superglue but that's a whole new can of worms with it's own problems IE: Glued eyelids, eyebals, fingers etc.

[adrian]

This is the offending object. It's only a practice piece but it would have been nice if it had stayed in one piece.
Yeah! I know it doesn't look too flash but what can I say........I'm a virgin. One day's experience. The only other thing I have done on my new toy is to turn a piece of pine into a toothpick and a pile of woodchips.
I suppose I should have also mentioned that the tree was only about 3 or 4 years old so it was quite pulpy.....like a palm. Good to practice on though.

[river rat]

adrian,
What about boiling the wood after rough turning it or Ldd it . I have not tryed either of the 2 methods yet. I read about them on the American Association of Woodturners and here is the link http://www.woodturner.org/ like this forum it is a good resurce of info

River Rat

[rsser]

If you're green turning and want it finished immediately, turn your walls thin and even in one session. Some people then microwave the item. Even then, cracks often happen.

General rule of thumb is that wood takes one year to dry for every 25mm of thickness, and very often you need to seal the end grain with paint or wax to avoid checking.

Jarrah is also good to turn.

[adrian]

I turned the next piece of the trunk the following day. I tried the microwave method as suggested by Brudda and 2 days later there is no sign of cracks.

It looks like there are more woodworkers on the Mid North Coast than I first thought. I went out four wheel driving yesterday with the thought of knoodling about in the woodpiles that the loggers reject. (Logging is a big industry here) In one clearing there were dozens of 400 - 500mm sections of trunk and it was obvious that someone had continually cut through the trunks looking for viable wood. I don't think that is something the loggers would do. Without exception, every one had a large star shaped crack running through the trunk. I took one home and split it down the centre and turned it for practice and it has turned out to be a nice piece of wood. I think I might be doing some more four wheel driving soon because I don't want to be wasting my money buying turning blanks yet.