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rsser
7th July 2005, 04:44 PM
It's a highly figured lump of Tas blackwood with a sizeable section of cream sapwood. A bowl btw.

The tear-out is in the sapwood on the outside rim. I've tried fine cuts with a gouge, fine shear-scaping, and the same with the grain swelled by water. I'm cutting in the right direction; the tools are sharp. The tear-out continues.

Sanding it out will take ages and fill the workspace with stuff I'd rather not have.

Advice gratefully received!

Cliff Rogers
7th July 2005, 08:43 PM
Is it going to be a gallery piece or a utility piece?

Do you want to eat out of it?

If it's utility & yes then you'll have to resort to power sanding.

If it's to be a gallery piece & no, you can resort to chemicals to harden the soft wood so it doesn't tear.

This one STINKS but it works with rotten wood....

If you don't like the smell of thinners (fingernail polish remover) stop now.

Get yourself some Adease Floorseal & the thinner to go with it.
You will need to do this in a well ventilated shed/workshop and/or wear a good respirator.
Make up a very thin batch IE: 50% thinners & soak the piece in it... slop it on, keep rewetting it paying extra attention to the soft wood. When you've run out of the batch you made up (or can't stand the smell any longer :( ) put it OUTSIDE to dry. The next day you can attack it with a smaller amout with only about 25 - 30 % thinners & do the same. You will notice that the hard wood won't soak up any more but the soft wood will. Now you have to decide for yourself how thirsty the soft wood is/was as to whether it needs another thicker coat or not. Once it is good & hard, may thake a couple of days, you can go back to turning it without the soft wood tearing.

Hope that helps.

RETIRED
7th July 2005, 10:58 PM
Ern. Try using a very sharp scraper the old fashioned way: Blade downhill and flat on the rest. Use light cuts. Super glue sometimes helps too.

Blackwood can be a mongrel at times.

Cliff: Acetone is nail polish remover.

Cliff Rogers
7th July 2005, 11:02 PM
No, nail polish remover has Acetone in it, that's the smell I was trying to describe. ;)

RETIRED
7th July 2005, 11:05 PM
Quite right Cliff.

gatiep
7th July 2005, 11:09 PM
Rssr


I'm with on this. Use the thin superglue. It penetrates really well and will stop the tear out.

Cliff Rogers
7th July 2005, 11:21 PM
You need a LOT of superglue for a big piece.

A $20 can of Adease goes a LOT further than a $20 bottle of Superglue.

gatiep
7th July 2005, 11:54 PM
You need a LOT of superglue for a big piece.

A $20 can of Adease goes a LOT further than a $20 bottle of Superglue.

That is true but usually the problem area is small. Good turning techniques, sharp tools, local sanding etc help reduce the area and only after doing all that will I consider using the superglue. I definately don't advocate the use of it thereby promoting a'she'll be right mate' attitude to turning.

Cliff Rogers
8th July 2005, 12:06 AM
The method I have suggested was actually recommended to me by a professional turner for turning very spalted, rotten wood.
I suggested it here 'cos I reckon Ern has the experience to have already tried several 'good turning techniques & sharp tools' & he was looking for new ideas.

gatiep
8th July 2005, 01:12 AM
And I recommended the above, because that is what I use and now that you have mentioned it: With Ern's capabilities the area will be even smaller! Good old hotstuff is my preferred one of many choices, partly too because I always have some on hand.

Anyway, happy fishing!

rsser
8th July 2005, 10:05 AM
Thanks Guys. I appreciate your going to the trouble of commenting.

Yep, it'll be a 'gallery' piece Cliff so chemicals can be considered.

The sapwood is softer than the heartwood of course but the grain is interlocked too.

What's the effect of Adease or CA on the finish? Presumably it will reduce the rate of oil absorbtion so I could perhaps try to only coat the sapwood.

Will try a sharp flat scraper first (or maybe the Munro hollower now that I think about it).

Cliff Rogers
8th July 2005, 01:04 PM
...What's the effect of Adease or CA on the finish? ....
Both can be used as a finish in their own right. Both will stop oil from soaking in.

rsser
8th July 2005, 02:38 PM
Thanks Cliff. Thought so.

Got a heap of Norfolk pine spalting away too so it sounds like Adease could get some use beyond this project.

rsser
9th July 2005, 04:01 PM
Good call .. flat-held sharp scraper did the trick. Assumed you meant with burr left on - anyway, it worked.

Thanks again all.

RETIRED
9th July 2005, 11:40 PM
Yep. Good.

outback
10th July 2005, 12:32 PM
AWW, shucks, don't ya love it when someone has a specific problem like this and everyone pitched in and fixes it.


Makes me feel all warm and gooey.


Glad to hear it all worked out for ya Ern. :)

rsser
10th July 2005, 05:00 PM
Thanks Outback.

Will post a pic or two.

... btw: sanding the outside caused few good sized checks. 's right; Tas Blackwood can be a mongrel.

rsser
11th July 2005, 11:50 AM
Some amazing chatoyance on this lump; worth persisting. Shown with one coat of Danish oil.

Cliff Rogers
11th July 2005, 01:45 PM
Yeap, looks good.

rsser
24th September 2005, 04:40 PM
End result; thanks guys.

(Now why the h*ll didn't I get a truckload of timber like this!)

Skew ChiDAMN!!
24th September 2005, 07:14 PM
Very nice! I can see why you wanted to include the sapwood...

dai sensei
25th September 2005, 09:51 AM
The results were worth the effort. Well done Ern.