JANKA HARDNESS

[odie]

Anyone here using Janka hardness testing results to determine the suitability of woods for turning purposes?

 

[Justin Stephen]

I have looked at it on a few occasions, although I am much more turned off by woods that are too soft than woods that are too hard. I also get concerned about woods that are too light, which is why I rarely turn butternut.

 

[robo hippy]

Hmm, well, I never have used the table to tell me how hard a piece is, though I have looked up some to see how they compare. The harder the wood is, the more likely it is to crack when dropped, or to split if you put some thing hot in it.

I would guess hardness would be important for detail work like finials. I remember Ashley Harwood talking about how she had a number of finials snap before she started using ebony exclusively. I gave her a couple of Mountain Mahogany finial blanks down in Atlanta, but haven't heard if she tried them. I would guess that hardness, as well as grain structure are important for detail type work as well.

I was only able to get my hands on Butternut once out west here. Lovely brown color, and the scalloped growth rings really helped it sell.

robo hippy

 

[odie]

also get concerned about woods that are too light

I've heard comments that wood turnings made from light woods, don't particularly sell well. Is that the reason for your comment here, Justin?

I've never been concerned with the Janka scale, was just wondering how other turners think of it.....if they do at all......

After purchasing a block of marblewood recently, I noticed a reference to the Janka scale. I've turned this wood before, and it does seem to be very hard......hard in a way that isn't the same as some of the other hard/dense exotics.

ko

 

[Bill Boehme]

... I've heard comments that wood turnings made from light woods, don't particularly sell well....

If you're talking about craft show type sales, it's not lightweight wood that's the problem, it's lightweight turnings. Thin and lightweight may impress other turners, but not buyers.

 

[hockenbery]

If you're talking about craft show type sales, it's not lightweight wood that's the problem, it's lightweight turnings. Thin and lightweight may impress other turners, but not buyers.

Weight is relative.
When a customer picks up a 12" diameter hollow form and gets a surprise from the lightness followed by a smile of appreciation, a sale is likely.

A functional bowl cannot appear to be fragile. It needs to give a sense of strength when picked up.
For fundtional bowls like, Reed mentioned, the softer hardwoods hold up better than the harder denser woods. A soft maple bowl is more likely to dent than split when dropped. An Osage Orange bowl is more likely to crack since it won't dent.

I make some functional bowls from the harder woods like Osage Orange, Beech. Pecan, and Hickory.
I just know they are less likely to be in use in a hundred years than a soft maple bowl.

 

[odie]

If you're talking about craft show type sales, it's not lightweight wood that's the problem, it's lightweight turnings. Thin and lightweight may impress other turners, but not buyers.

Ya, I'm beginning to realize this, Bill. I worked for years to perfect a system of turning thin wall bowls, and after a few more recent years of regular sales, I'm realizing this isn't a sales point at all. There might be the occasional buyer who does care about thin and light turnings, but for the most part, they don't seem to care much about this at all........

Doing thin wall bowls over and over again is great for perfecting one's skills......but the primary beneficiary isn't the end user......it's the turner!

ko

 

[odie]

I've heard comments that wood turnings made from light woods, don't particularly sell well. Is that the reason for your comment here, Justin?

My comment here, Justin......is in reference to the lightness or darkness of the wood. For example, light wood like maple, and dark wood, like walnut. Some have apparently taken my question to address the weight of the wood (or finished product). All commentary is good for thought, regardless.......

ko

 

[Bill Boehme]

I think that everybody likes wood that has great figure and that often means darker wood, but not too dark. However, light colored wood with especially nice figure is also very attractive. I'm thinking about curly maple that is dyed to accentuate the figure. Also box elder with lots of red streaks is very desirable. In the case of box elder, bleaching the wood makes it even more attractive. I also like plain light colored maple for making basket illusion pieces.

My apologies for misreading your question. I think that I was equating hardness with weight which is not necessarily true.

 

[Jamie Straw]

I had never heard of the Janka hardness test/scale before, thanks for posting about it. I see our Ipe deck wood is right at the tippy-top, tied with four other woods.

 

[Bill Boehme]

How do you like the ipe deck? The redwood boards on our deck are very old and I am in the process of removing them. Redwood has increased in price about ten fold since I first built the deck and I am contemplating other choices. I know that it is even more expensive than redwood, but I've been numbed to the cost of wood after buying some fancy turning blanks. I paid a couple hundred dollars for a hunk of mesquite last year and I live where mesquite grows on trees.

 

[robo hippy]

For sales purposes, how the bowl 'feels' is at least as important as color. Plain white ash does not sell well for me. Same with white maple. A piece of the 'olive' ash, where all the heart wood is that darker brown, is impossible to keep on the shelves. Black walnut sells in spurts, some times you can't give it away, some times it is difficult to keep in stock. Cherry sells well. Madrone sells very well for me, in part because not many of us work it and because of the nice warm red color. People need to pick up the bowls and hold and caress them before buying. This makes on line sales very difficult for me. Of course, one person will love a piece that another can't stand....

robo hippy

 

[Justin Stephen]

I've heard comments that wood turnings made from light woods, don't particularly sell well. Is that the reason for your comment here, Justin?

I couldn't really say from experience as I have minimal experience selling my work at shows, but I would say that my point is similar. I turn what I like myself, first and foremost, and the things I love about wood are its looks, its tactility and its heft. A larger hardwood bowl should have some heft to it. Obviously, as mentioned by you and others, wall thickness is just as much a function towards this as wood species.

I was gifted a large butternut bowl by an in-law a few years back. Never having worked with the wood before, I was shocked as to how light it is while at the same time being remarkably pretty wood. Black walnut is about as light of wood I will use for the most part. While light itself, it is still substantially heavier than butternut (38 lbs/cubic foot vs. 27 lbs/cubic foot, or about 40% heavier). Of course, I reserve the right to change my mind later. I do love the looks of butternut.

 

[Jamie Straw]

How do you like the ipe deck? The redwood boards on our deck are very old and I am in the process of removing them. Redwood has increased in price about ten fold since I first built the deck and I am contemplating other choices. I know that it is even more expensive than redwood, but I've been numbed to the cost of wood after buying some fancy turning blanks. I paid a couple hundred dollars for a hunk of mesquite last year and I live where mesquite grows on trees.

The Ipe is incredibly strong, will not sag between the joists, and will last at least 25 years (probably more). I gathered wisdom from deck builders beforehand, and learned (a) pre-drill every hole (b) use high-quality fasteners and (c) use the right saw blade on your miter saw. I bought the star-head fasteners from Canada (can get the brand name if you wish), with lots of driver-bits because they will break (and pierce your fingers if you're not careful). Being on an island in Puget Sound, the deck gets very slick with northwest slime if it's not kept clean. Don't know that it's any more of a problem with Ipe than it would be with a different wood.

 

[Bill Boehme]

The Ipe is incredibly strong, will not sag between the joists, and will last at least 25 years (probably more). I gathered wisdom from deck builders beforehand, and learned (a) pre-drill every hole (b) use high-quality fasteners and (c) use the right saw blade on your miter saw. I bought the star-head fasteners from Canada (can get the brand name if you wish), with lots of driver-bits because they will break (and pierce your fingers if you're not careful). Being on an island in Puget Sound, the deck gets very slick with northwest slime if it's not kept clean. Don't know that it's any more of a problem with Ipe than it would be with a different wood.

Thanks for the information.Our deck is close to 25 years old. I used regular galvanized deck screws because that's what was available back then. I won't be doing that this time because the Phillips screws cam out or strip too easily. I had to dig out a couple hundred of them with a hole saw. Fortunately, about 80% of them came out without too much trouble. The head snapped off a hundred or so screws so I had to go after those with vice grips. When I built the deck, I had to predrill the holes because the joists are CCA treated SYP which is really hard and heavy. They are still in perfect condition which is great.

I assume that you used the generic Torx screws. I will either do that or use the blind fasteners.

 

[Jamie Straw]

I assume that you used the generic Torx screws. I will either do that or use the blind fasteners.

Mmmmm, not exactly. PIcture below -- they are GRK Fin/Trim stainless steel, "Zip-Tip", W-cut thread. They were strongly recommended by the deck builders I consulted on Fine Homebuilding (back in the day when Taunton had decent forums). These guys were not weekend homeowner-builders, they built decks for a living, so I figured I'd save some grief by just following their recommendations. Hubby did 95% of the work, but I did enough to be glad we were using these screws and not something from the local hardware store. I tried to get them through Tacoma Screw, a big business not too far from where we live, but it turned out to be cheaper to order them from the company in Canada. They are manufactured in Germany and Taiwan. With the Ipe combined with pressure treated SYP, your deck should last a generation at least!

 

[John Tisdale]

Bill,
First, my apologies for diluting the subject, but...regarding your deck.
TWO THINGS:
- Take a look a Trex - it's a man-made material that lasts forever - use wood where it counts. And if you want that natural look, I'll sell you bags of leaves to scatter over the boards - looks great.
- On screws, go to www.mcfeelys.com - their decking screws have thread-length designed for the thickness of the board being fastened down plus the threads are proud of the upper shaft - pulls the boards down in one effort.

 

[olaf Vogel]

- Take a look a Trex - it's a man-made material that lasts forever - use wood where it counts.

I've got TREX on my front deck at the cottage, where its constantly wet and extremely exposed to the sun.

After 5 years, its very faded and worn (even though its a cottage and gets little traffic).
Also it sags between the joists, so lots of joists are needed. The hot sun has caused warping.
Southern Ontario is a fairly moderate climate, although cooler than Texas in the summer.

Obviously I'm not a huge fan.
Not sure any more what the cost is relative to IPE, but I really prefer the look of IPE and am regretting getting the TREX.

Just my 2c

 

[olaf Vogel]

Back on the topic at hand...hardness.

I'm trying to finish off an old project - a pair of speakers that were inspired by these B&W 802

I've built the base a while ago and finished them in Bubinga veneer.
Now I need to turn the tops - ideally out of bubinga as well.

Its pretty high on the Janka scale at 2400, far harder than anything I've tried on the past.
Has anyone tried turning this stuff?

 

[Bill Boehme]

Bill,
First, my apologies for diluting the subject, but...regarding your deck.
TWO THINGS:
- Take a look a Trex - it's a man-made material that lasts forever - use wood where it counts. And if you want that natural look, I'll sell you bags of leaves to scatter over the boards - looks great.
- On screws, go to www.mcfeelys.com - their decking screws have thread-length designed for the thickness of the board being fastened down plus the threads are proud of the upper shaft - pulls the boards down in one effort.

I've got TREX on my front deck at the cottage, where its constantly wet and extremely exposed to the sun.

After 5 years, its very faded and worn (even though its a cottage and gets little traffic).
Also it sags between the joists, so lots of joists are needed. The hot sun has caused warping.
Southern Ontario is a fairly moderate climate, although cooler than Texas in the summer.

I'm with Olaf on Trex. Trex was used for an elevated boardwalk between buildings where I worked. First the color faded to white then they sagged between joists in the Texas heat then the surface wore from foot traffic and became slick so an outdoor carpet was installed on top of it. I suppose that it is OK for some purposes, but the look after a few years turned me off.

If I go with ipe I will probably use hidden fasteners. Thanks for the offer of leaves, but we are well stocked. They grow on trees around here and are on the verge of dropping.

 

[Dean Center]

Back on the topic at hand...hardness.

I'm trying to finish off an old project - a pair of speakers that were inspired by these B&W 802

I've built the base a while ago and finished them in Bubinga veneer.
Now I need to turn the tops - ideally out of bubinga as well.

Its pretty high on the Janka scale at 2400, far harder than anything I've tried on the past.
Has anyone tried turning this stuff?

I've used bubinga for small items and didn't notice any issues. Can't say how it would be in larger pieces. I recall hearing that bubinga was used in decking for railroad cars in the distant past, so it must be very tough.

 

[olaf Vogel]

I've used bubinga for small items and didn't notice any issues. Can't say how it would be in larger pieces. I recall hearing that bubinga was used in decking for railroad cars in the distant past, so it must be very tough.

Fancy railroad car!

Thanks for the feedback. I'll give it a try.
Its from a lumber mill near me that log of specializes in exotics. I rarely go there because its expensive.
But last time, they had a LARGE bubinga sawn into slabs 3" thick. the centre slabs were 8 feet wide by 16 feet long!!! $3000 each.

That would be a hell of a conference table and likely in the $20k range when done.
Gorgeous!

I've made tables before but that slab won't even fit in my shop.

 

[RichColvin]

The wood database (http://www.wood-database.com/bubinga/) has this to say about bubinga :

Workability: Easy to work overall, though depending upon the species Bubinga can have silica present, which can prematurely dull cutting edges. Also, on pieces with figured or interlocking grain, tearout can occur during planing or other machining operations. Gluing can occasionally be problematic due to Bubinga’s high density and natural oils. Turns and finishes well.
​

I found the statement about silica interesting.