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John Neel
12-03-2010, 12:21 PM
White oak and hard maple are the hardest woods I have ever used. How do you find working woods above 3000 on the attached Janka scale?

What do they do to your power tools? Are there particular problems?

What about hand tools: saws, planes, chisels, cabinet scrapers?

How about sanding and finishing?

I find myself wanting to use something a little more exotic. What should I expect?

John Neel
12-03-2010, 12:27 PM
Janka Scale of Hardness


4500 Lignum Vitae (Guaiacum species only)
3800 Snakewood
3680 Brazilian Walnut (Ipe)
3540 Brazilian Teak (Cumaru)
3220 Ebony
3190 Bolivian Cherry (Cerezo)
3000 Brazilian Rosewood (Tamarindo)
2900 Bloodwood
2820 Brazilian Cherry (Jatoba)
2473 Spotted Gum
2345 Mesquite
2300 Caribbean Rosewood
2200 Santos Mahogany
2200 Bocote
2170 Asian Rosewood
2160 Goncalo Alves
2135 Brushbox
2046 Australian Beech
2023 Karri
2023 Sydney Blue
1980 Bubinga
1925 Merbau
1910 Jarrah
1860 Purpleheart
1820 Pecan
1820 Hickory
1820 Pecan
1780 Pau Ferro
1725 African Padauk
1720 African Blackwood
1710 Kempas
1700 Locust
1686 Rose River Gum
1630 Wenge
1510 Sapele
1500 Brazilian Maple
1450 Hard maple
1450 North American Maple
1400 Caribbean Walnut
1375 Australian Cypress
1360 White Oak
1350 Tasmanian Oak
1320 White Ash
1300 American Beech
1290 Angelique Teak
1290 Red Oak (Northern)
1260 Yellow Birch
1260 Red Oak
1225 Heart Pine
1155 True Teak
1100 Makore
1100 Heritage Oak
1100 Alpine Ash
1010 North American Walnut
1010 Black Walnut
1000 Teak
950 North American Cherry
950 Black Cherry
870 So. Yellow Pine (longleaf)
800 Honduran Mahogany
690 So. Yellow Pine (loblolly & short leaf)
660 Douglas Fir
420 White Pine
410 Basswood
350 Western Red Cedar
100 Balsa

David Hawxhurst
12-03-2010, 1:08 PM
White oak and hard maple are the hardest woods I have ever used. How do you find working woods above 3000 on the attached Janka scale? haven't worked with anything harder than Jatoba so far, but for the most part i've not had any problems. some maybe more prone to chip out (kind like hickory).

What do they do to your power tools? dull them a little faster but not much. Are there particular problems? most tend to change color when exposed to uv light regardless of finish (some darken some lighten other change color.

What about hand tools: saws, planes, chisels, cabinet scrapers? work fine, just keep them sharp (you probably already do this)

How about sanding and finishing? i do my sanding by hand and have not noticed it to be anymore diffucult than maple or cherry. haven't had any problems with finishing them. some are high in oil so you may to wipe them with something like acetone just before applying the finish.

I find myself wanting to use something a little more exotic. What should I expect?go for it. there are a large number of exotics available (more than you have listed on you janka scale). i work with mostly exotics mostly for there colors.

Tom Walz
12-03-2010, 2:14 PM
My experience in these woods is as an advisor and tool builder in industrial applications. It is not directly relevant but may help.

Many of the harder woods are mineral rich. This is often described as cutting sand. Everyone knows this isn't technically correct but it does give a good idea of the problem.

We build custom blades with Cermet 2 tips to give longer wear. There are retail, long wear tools as well. I would look for tools that advertise long life tips. Freud's TiCo did well in our testing. Amana and Vermont American (now part of Robert Bosch) may reference Dyanite or Dianite on their saw blade packaging. This is a process that increases both wear life and toughness in carbide tips. Also look for Titanium, Tantalum and Niobium on the label as carbide additives. This is a pretty safe bet. I have never seen a retail blade advertising long life tips that wasn't telling the truth.

Perry of Superior Saw in Tacoma, WA just stopped by.

Perry says to cut slowly and be prepared to sharpen often if you use a circular saw. He also suggested that a band saw may work better for something such as a deck.

He had a customer build an average size deck and it took 4 saw blades and each was sharpened once.

You will be exposed to new allergens. Watch for the usual symptoms.

Some of the hardest woods also have pretty strong chemistries hence the mineral absorption and allergens.

Richard M. Wolfe
12-04-2010, 1:16 AM
Each wood species can have different characteristics besides just the hardness. I work mesquite a good bit and although hard love working it as it routes beautifully. I say the pecan around here is generally harder than mesquite and in addition is more fibrous. I don't use imported exotics - about the hardest thing I've worked in native woods is bois d'arc (osage orange). I just cut some yesterday to make a cutting board and made a bookcase from it last year (I posted it in the projects forum). Cutting is OK as long as you use sharp tools and for sanding stepped to a coarser series to get the job done in a reasonable time and you need to keep a router moving or it can burn pretty bad. I'd rather cut and work something hard like mesquite than try to work something like spruce - that fibrous stuff is like cutting a bunch of bedsheets.

Steve knight
12-04-2010, 2:05 AM
they always have purpleheart too low. but there are a lot of species of it. but my experience it is right around bloodwood if not a bit harder.

Don Alexander
12-04-2010, 2:37 AM
my experience with Lignum has been that it turns well and is easy to get smooth much easier to turn than several of the woods farther down the list go figure :)

Steve knight
12-04-2010, 12:44 PM
I forgot to add the harder the wood the more teeth the better. The tropical's tend to be more stable too. When I had my contractors saw and changed from a rip blade to a forrest 30t blade I got far faster cutting on the harder woods. they cut faster then American hardwoods.
some can be real work to sand and shape like bubinga seems to really resist sanding.

Howard Acheson
12-04-2010, 5:08 PM
>>>> How do you find working woods above 3000

I have worked with Ipe, Cumaru and Jatoba. Not a lot but occasionally.

They tend to dull tools more rapidly but that's to be expected. Nothing you can do about it if you want to use the wood.

Hard, tropical woods can be oily so sanding will may paper more rapidly. For the oilier woods finishing with oil based finishes can be problematic. The wood oils negatively react with the linseed oils in oil based finishes. A barrier coat of shellac generally resolves any issues. The native oil has a plus in that those woods will last forever in exterior and salt water conditions.