PDA

View Full Version : Finishing Rough Turnings



Seventh Wood
3rd July 2009, 12:08 AM
Hi All,

I have finally reached the stage of finish turning some of the stuff I rough turned up to a year ago (SWMBO is getting alarmed at the number of rough bowls, etc building up in the shed so I had to do something!)

I have been rough turning as per the Raffan Bowl Turning book, though I normally seal the bowls promptly after rough turning with end grain sealer, while Raffan says he does not bother. Of the rough bowls that I have not sealed, a large number (over 50%) have developed cracks that may make the bowls useless, while I have not had a problem with sealed bowls - I expect I'll just have to wait longer before finishing them.

The first is a 170 mm Grevillia Robusta bowl from a timber haul from our street in Adelaide. I have had a lot of cracking in the blanks, even though I have cut it down to relatively small blanks and sealed the end grain. I rough turned the blank about a year ago and did not seal it. The resulting bowl turned nicely and appeared to be fully seasoned, with only small surface cracks. I managed to incorporate a branch into the rim, as in the side view of the bowl, and it shows a good ray pattern and appears to be sound. The colour is very pale pink, quite unlike the dark brown of Northern Silky Oak that I turned recently.

The other is a 200 mm Pepper Tree bowl from a partly spalted tree (I did a post on it at the time). I have a shot of the freshly turned rough bowl and the finished bowl. The bowl distorted spectacularly whiel seasoning but I managed to retrieve a nice bowl. I took all the usual precautions - dust extractor, respirator, etc when turning it and it was difficult to get a good finish on the partly spalted wood. There are some minor cracks and the burl-like inclusions penetrate right trhough the wood. The colour of the spalted wood has preserved well though.

I have since done about 50 or so rough bowls up to 400 mm diameter. It can be addictive with long, wet, continuous shavings coming off and shooting all over the shed (and rusting my tools if I am not quick in cleaning up). Recent stuff turned includes Green Mallee, Plane Tree, Willow Myrtle (lovely deep red timber), various Melaleuca and Ash from the dying trees in the Adelaide parklands.

Cheers,

Seventh Wood from 7Hill

jefferson
3rd July 2009, 12:55 AM
Seventh,

Apologies, but I didn't like the foot on the bowl. The foot lifts the bowl off the base too high and I don't like it. (That's plain English for something technical I'm sure.)

I am certainly no pro, but others here on the board are more than expert - and I'm sure they will give you constructive feedback on your forms. And also tips on drying and everything else related to turning.

I've put stuff up too - most (if not all of it) has been fairly ordinary. But the feedback, suggestions and insights make us all better turners.

Such a shame you are in SA. The Vic WWF are a top crew of blokes (plus the Tea Lady). :wink:

Jeff

artme
3rd July 2009, 08:43 AM
Nice Turning SW but I must agree with Jefferson's foot comment.

I really like that Pepper Tree, and you did well to save such a good bowl from it.

Rum Pig
3rd July 2009, 09:28 AM
Hi All,

I have finally reached the stage of finish turning some of the stuff I rough turned up to a year ago (SWMBO is getting alarmed at the number of rough bowls, etc building up in the shed so I had to do something!)

I have been rough turning as per the Raffan Bowl Turning book, though I normally seal the bowls promptly after rough turning with end grain sealer, while Raffan says he does not bother. Of the rough bowls that I have not sealed, a large number (over 50%) have developed cracks that may make the bowls useless, while I have not had a problem with sealed bowls - I expect I'll just have to wait longer before finishing them.


Cheers,

Seventh Wood from 7Hill

:oYou let SWMBO near your shed:o :slap2:
As for your sealing/not sealing just do what works for you. Raffan is a great turner but he does not live with you so climate and storage condition will vary so his technique may not work. But it was worth a try.

I like the pepper bowl:2tsup::2tsup:
And I agree with Seventh Wood regarding the foot.

Ed Reiss
3rd July 2009, 12:14 PM
Ditto on the too large foot...reduce the foot height by 2/3rds for a much better overall look.

CameronPotter
3rd July 2009, 12:43 PM
Just to be different I will say that I quite like the foot! The wood is not that exciting to me (unlike the Pepper Tree) and I think that it needs a little something to add character. It may not be the most traditional shape - but then I wasn't ever one to follow fashion. :)

Actually, there are two constructive comments that I would make:
1. With a large foot like that - you could almost even make it a bit bigger and make it a bowl/goblet hybrid. I think that this would be an interesting play on shapes.
2. I am not thrilled with the angle of the foot. compared the the rest of the shape - but as we have already established, aesthetics are not universal.:wink:

Cheers

Cam

Seventh Wood
4th July 2009, 09:12 AM
HI All,

I am fascinated by all of the comments on the foot and agree that it could be improved. I don't have a standard foot design and have done goblet style (as per Cam's comment) and tend to vary it depending on how I feel on the day. Another Silky bowl I did the same session as this one has a foot only 3 mm high!

One thing I need to do is some reverse chucking. Then I can optimise the design to the bowl and get away from the dovetail attachment look.

I originally roughed the foot oversize for my Nova100 mm jaws, but the foot distorted and shrank too small to use these jaws. My remaining option was to recess dovetail for my 50 mm jaws, as I do not have a set of step jaws.

Thnks for the comments

Cheers,

7th Wood

NeilS
4th July 2009, 06:27 PM
Such a shame you are in SA. The Vic WWF are a top crew of blokes (plus the Tea Lady). :wink:



But, what we crow eaters lack in numbers we make up for in ....... :)

Neil

rsser
5th July 2009, 03:44 PM
... in what Neil? ;-}

7th Wood, that peppercorn wood is a rip snorter. Great find and nice treatment.

As for drying green turned bowls, Raffan's book says he drops a batch into a box and mixes them up from time to time. That would slow down the drying. But if you just have a few and the species is known to be unstable (Melaleuca, Tas. Myrtle etc) then end-grain sealing is good insurance.

Watch out for blue-stain though; big Plane tree lumps can develop this over time.

Looking forward to seeing more of your finished work.

PAH1
5th July 2009, 04:26 PM
I have found that a cardboard box is great for batches, however 3-4 sheets of newpaper is the best for single turnings. The success rate varies depending on the species, generally the "oak" type timbers have the worst success rate. One thing that richard does that most do not and I think this explains much of the difference in the success rate, is to make a thin cut on the end grain to check for micro cracks. If you find some you just keep shortening the stick untill you get clean wood. It is amazing how far they can go in, even in green wood. Sometimes you can stop a crack from spreading in green wood with an application of super glue. The cheap discount store stuff works as well as anything else.

orraloon
5th July 2009, 06:29 PM
Nice work Seventh. The pepper tree is very nice wood. I can live with the foot on the other as there are all sorts of tastes out there. No matter what you do with form some will like it and some wont. A bowl is seldom viewed from side on like the pic anyhow.
Regards
John