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Paulphot
29th September 2010, 02:12 PM
I was given some pieces of black wattle about 2 months ago from a tree that was cut down. It was full of borers and there was plenty of dry timber in it, which is what I have started turning.

While the long grain has been fine, I just can't get into the end-grain. I know I'm going at the bowl in a different way but this is the way the piece was cut. I'll take some pics tonight and post them up.

Paul

RETIRED
29th September 2010, 05:36 PM
Add pics of how you are trying to do it also if you can.

Paulphot
29th September 2010, 07:10 PM
I know I am trying to hog out the inside of the bowl into end grain, that is the problem. I'll get some pics up soon.

BobL
29th September 2010, 07:18 PM
Dry Wattle Black {Acacia mangium} is rated at 1750 lbs force hardness while Wattle Green {Acacia decurrens} is 2250 lbs.
Both are softer than Gum Spotted {Eucalyptus maculate} being around 2470 lb

The hardest reported wattle is Wattle Lakewood {Acacia enervia} and at 4150 lbs is the 12the hardest wood on earth.

Wattle Australian Ironwood {Acacia excelsa} is 4050 lbs and 16th hardest.

All other Wattles are less than those above.

REF: Wood Species Janka Hardness Scale/Chart By Common/Trade Name (http://www.morlanwoodgifts.com/MM011.ASP?pageno=207)

artme
29th September 2010, 08:42 PM
Bob, you and Runge should join forces!!:D

At those sorts of hardnesses I guess 12th and 16 are relative. Generally they can be described as bloody hard.!!:wink:

texx
29th September 2010, 08:47 PM
interesting link bob thanks , but i had a good look on there and i cant find cooktown iron wood ........ Erythropleum Chlorostachys.
shame cos i have a little lump of it and would like to of know where it fell on the hardness scale .

Paulphot
29th September 2010, 09:25 PM
Well here are the pics.

The problem is going into the end grain, cutting the long grain is fine.

http://i44.photobucket.com/albums/f47/paulphot/Woodwork/20100929pjm002.jpg


It's starting to crack a bit.
http://i44.photobucket.com/albums/f47/paulphot/Woodwork/20100929pjm013.jpg

http://i44.photobucket.com/albums/f47/paulphot/Woodwork/20100929pjm012.jpg


This is the other half of the blank. I think I'll be cutting it up for pen blanks.
http://i44.photobucket.com/albums/f47/paulphot/Woodwork/20100929pjm010.jpg

http://i44.photobucket.com/albums/f47/paulphot/Woodwork/20100929pjm003.jpg

BobL
29th September 2010, 09:32 PM
interesting link bob thanks , but i had a good look on there and i cant find cooktown iron wood ........ Erythropleum Chlorostachys.
shame cos i have a little lump of it and would like to of know where it fell on the hardness scale .

It's there - listed as Ebony Red {Erythrophleum chlorostachys} 3820 = so yeah pretty hard stuff, 18th hardest in the world in fact.

BobL
29th September 2010, 09:36 PM
Bob, you and Runge should join forces!!:D

At those sorts of hardnesses I guess 12th and 16 are relative. Generally they can be described as bloody hard.!!:wink:

They're only 100 lbs difference and at 4000+lbs there are almost certainly individual bits of the excelsa that will be harder than the enervia.

RETIRED
29th September 2010, 10:12 PM
Paul. I will hazard a guess and say that you are trying to turn it like a normal bowl, that is from outside in.

It doesn't work that well. You have to go from inside out with a very sharp raked back bowl gouge or a lady finger grind detail gouge.

Rest on centre line (allow for tool thickness) and tool almost horizontal. It helps to drill about a 3/8" hole to just above the depth you want.

If I get time tomorrow I will photograph what I mean.

Paulphot
29th September 2010, 11:29 PM
, I have been trying both outside in and inside out. The inside out seems to catch less and I'm using a bowl gouge with a fingernail grind, it's just taking a long time. I had a hole drilled into it, 12mm and I have gone down to the end of that. I'll drill out some more on the weekend. I thought I would try and get a hole going so I could open up the long grain and reduce the amount of end grain I was cutting.
Thanks for the advice, I'll see how I go.

thumb trimmer
29th September 2010, 11:43 PM
Paulphot ... potentially funny question. Why have you got the worm screw going into the 'foot' of the bowl??? :think:

Paulphot
30th September 2010, 12:52 AM
Funny story...the blank wasn't very square so I couldn't mount it on a faceplate. I decided to worm screw it on the top where I would cut away, then wasn't happy with the purchase I had on the blank so thought I would mount it the other way...that was even worse so I swapped it back. I'll turn the tenon off when I finish and that will get rid of most of the screw hole.
I look at it as a design feature...;)

NeilS
30th September 2010, 01:05 PM
cooktown iron wood ........ Erythropleum Chlorostachys.
shame cos i have a little lump of it and would like to of know where it fell on the hardness scale .

Just don't let it fall on your toe...:U... it's hard and heavy!

.

RETIRED
30th September 2010, 07:16 PM
This is the way that I do end grain turning.

A swept back bowl gouge or a lady finger nail grind on a detail gouge can be used. These are the angles I have on the detail gouge.

148864148862

Set tool rest so that tool is almost horizontal and the tip of the tool is on centre. I have the handle down a bit because of habit as a spindle turner.

148863

This allows you to start the cut here,

148865

I use a rest just long enough to do the job but it doesn't matter. Put the palm of your hand on the outside of the rest and your fingers over the tool.

148867

Put the flute of the tool in the direction of cut at about 45 degrees or 20 to 2.

148866

Now just squeeze or pull.

148869

You can remove a lot of material quickly with this cut but the chisel needs to be sharp and will require a bit of sharpening in hard timbers.

148868

Paulphot
30th September 2010, 08:42 PM
, thanks for taking the time to do these photos for me, I really appreciate it. I'll get my detail gouge super sharp and give it a go over the weekend and let you know how I go.

TTIT
30th September 2010, 10:18 PM
Dry Wattle Black {Acacia mangium} is rated at 1750 lbs force hardness while Wattle Green {Acacia decurrens} is 2250 lbs.
Both are softer than Gum Spotted {Eucalyptus maculate} being around 2470 lb

The hardest reported wattle is Wattle Lakewood {Acacia enervia} and at 4150 lbs is the 12the hardest wood on earth.

Wattle Australian Ironwood {Acacia excelsa} is 4050 lbs and 16th hardest.

All other Wattles are less than those above.

REF: Wood Species Janka Hardness Scale/Chart By Common/Trade Name (http://www.morlanwoodgifts.com/MM011.ASP?pageno=207)Sorry to rain on your parade Bob but I wouldn't be staking anything of value on the info on that website :no: - more species missing than there are included - on both the hardest and softest woods lists. Most of those things are compiled from forestry departments lists from around the world so they only include commercially viable or popular timbers :shrug: .

BobL
30th September 2010, 10:27 PM
Sorry to rain on your parade Bob but I wouldn't be staking anything of value on the info on that website :no: - more species missing than there are included - on both the hardest and softest woods lists. Most of those things are compiled from forestry departments lists from around the world so they only include commercially viable or popular timbers :shrug: .

Yep I agree (I said that already about 3 times across the forums) but if you can post a more comprehensive list then lets see it.

jefferson
30th September 2010, 11:26 PM
Forget about whether the list is right or not. Just note the no. of Oz woods on the so-called "hardest" list. I don't think the numbers will worsen if ever corrected. Fortunate we are IMHO.

BobL
30th September 2010, 11:39 PM
Forget about whether the list is right or not. Just note the no. of Oz woods on the so-called "hardest" list. I don't think the numbers will worsen if ever corrected. Fortunate we are IMHO.

Fortunate we are I agree but I also think we employ perhaps more botanists and hopefully take care of our flora perhaps a touch more than the other two southern hemisphere continents. So while we still have a lot to learn we probably know a little more technically about our environment that they do. I am convinced there are probably more undiscovered/untested species of hardwood in SAmerica and Africa that are also not on that list.

But we are still very fortunate.