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View Full Version : Tear-outs on a blackwood table top















ozeb
22nd September 2006, 11:59 AM
I'm sure we have all had them at some time. How do I best deal with the problem? I don't feel like planing down any more. I might make things worse. I am trying Wattyl Sanding Sealer and that seems to fill in the tear-outs quite well. Is there any better way?

AlexS
22nd September 2006, 12:36 PM
If they aren't too deep, you may be able to work them out with a cabinet scraper. Make sure it's sharp (should be taking off shavings, not powder) and work a fair distance either side of the tear out.

Wood Borer
22nd September 2006, 02:52 PM
A scraper is great for this work as Alex mentioned.

Sometimes tearout is difficult to avoid but it can be minimised by closing the mouth of your plane and setting the plane very fine. Skewing the plane can help as well as planing across the grain at an angle that minimises the tearout.

Of course the blade must be razor sharp.

A low angle block plane sometimes works well because of the low angle and because of the narrow width in which case you can orientate plane to cope for the local grain without tearing out on nearby different curly grain which can happen with a wider blade.

ozeb
22nd September 2006, 03:02 PM
I was using an HNT Gordon plane which is one of the best tools that I have. And I do try to be careful about tear-outs by going across the grain if there is any doubt. Still, these things happen, and, unfortunately, the tear-out is too deep to scrape away. :mad:

AlexS
22nd September 2006, 07:15 PM
OK, if they're too deep to scrape out, you may be able to fill them with wax. You can buy coloured wax sticks from bunny's, but probably cheaper if you have a french polishers' supplier there. You may need to mix several colours to get a match, and if it's a large area, it will probably be camouflaged better by using several slightly different colours.
After filling, it can be sanded and finished as normal.

Auld Bassoon
22nd September 2006, 07:27 PM
I've been working with Blackwood quite a bit recently, and have found that changing the LV LA jack and #7 jointer irons from the standard 25o to 38o ones (properly sharp, of course) has all but eliminated the problem.

You do have to read the grain though, as there is a fair bit of reversing grain so you need to skew accordingly.

As others have said, a scraper also helps.

martrix
22nd September 2006, 07:40 PM
I was using an HNT Gordon plane which is one of the best tools that I have. And I do try to be careful about tear-outs by going across the grain if there is any doubt. Still, these things happen, and, unfortunately, the tear-out is too deep to scrape away. :mad:
Have you tried flipping the blade over so that the bevel is 90 degrees to the work and use it as a scraper? Very effective, but make sure you touch-up the blade so its razor sharp.
Should be able to handle mild figured blackwood when you have it set very fine...

ubeaut
23rd September 2006, 01:11 AM
Smart arrrrs answer - Don't get tear out to begin with.

A most effective way to stop tear-out is to place your thumb firmly into the throat of the plane effectively stopping the shavings from coming out and blocking the throat up. With this method you can literally plane against the grain without tear-out.

I wouldn't do a whole table top that way but it has stopped tear-out for me on some pretty wild timbers over the years. Have used it effectively on flame mahogany, quilted maple and fiddle-back in a variety of timbers.

Oh yeah.... if all else fails 60 grit on a really big linisher works wonders.

Cheers - Neil :)