Working with White Ash

Where I live, there is lots of White Ash stands. Also White ash works not too bad and is is quite strong. However I'm not able to find a lot of information on it or the design values in the tables. Does anyone have any data for this species of wood.
Thanks
New member,
Thane O'Dell

Hi Thane

No hard "data" to offer, but ash is very even and predictible, which is why native people made baskets w/ it.

Ash also steam bends wonderfully (snowshoe frames), and ash was traditional for canoe paddles b/c it is light yet strong and resilient. It also resists rot fairly well.

As a woodworker, I can say it works easily and takes a good finish, too. Grows nice and straight, as you must know...good saw logs! Would make a nice timber frame.

It seems to dry fairly fast, so shrinkage may be a concern in timber joinery. Anyone else have thoughts on that?

I have a 26'x8"x12" ash beam as a bottom cord in a multi king post truss over my spill way into my mill. This is the only stick of ash I have worked and I recall no problems working it, it is stable as well, and no major checks, unlike some of the spruce used in the same truss.

Tim

When it came time to build my own house a few years ago I selectively logged off all the larger ash and hemlock I had and got it all milled up on site with a Woodmiser sawmill. Ash is a beautiful wood to work with and looks great for my 3" x 6" braces and 4" x 6" floor joists. However, I have some 8" x 8" ash posts where the radial shrinkage has been huge -- I have some very, very large cracks in these timbers that I don't have in the hemlock a few feet away.

So my advice would be -- Ash is great for smaller timbers, but use something else for the larger stuff.

I'm guessing Tim's positive experience with large diameter ash is because his timber is outside over a spillway (high humidity) whereas mine is inside a low humidity wood heated house.

Thanks guys for sharing your experiences with me.
Michael, I visited your site and was impressed. I hope that one day I could build like that.
I quess that there is not much data on the design values for Ash that I could use for engineering. Would the strength of ash be similar to White Oak so I could use those numbers.
When get as much experience as you guys I won't have to do the math anymore or as much.
Thane

Ash posts, natural arch, and lower half of scarfed beam. Upper half is Hickory. Braces and floor joists are Red Oak.
The Purlins in this frame are Ash also. Frame is 13 yrs. old now and no problems with shrinkage. Initially some checks opened up during the winter, but after a couple years they settled down as the timbers dried out.

Did some quick googling and came up w/ this table on species properties:


It appears ash and white oak are very similar, which surprised me. I thought white oak would be noticeably stronger. But as you can see the two are nearly identical.



Ash, White: 0.60---1.74---43---7,410---1,160---1,910

Oak, White: 0.68---1.78---37---7,440---1,070---2,000


Complete table here (U.S. Forest Products Laboratory):

http://www.woodbin.com/ref/wood/strength_table.htm

(I'd still put my money on the oak in a stress test ).

It's tough stuff. I built side boards for the dump truck out of it. Has stood up to a lot of abuse, with no damagee.

I'd put my money on the ash if the stress test was how long the wood would last as an axe handle.

A couple of years ago the company I was working for advised a client not to use ash for his frame. He insisted on ash so it went ahead. One of the king posts almost split along its length over a period of a couple of days. Other shakes developed elsewhere in the frame. I wouldnt recommend ash

Nice insight, Mark.

Ash's flexibility would certainly help there. Same reason I wouldn't want a white oak canoe paddle (regardless of the added weight).

How many chops would it take for that kind of stress test? I love to split wood. That sort of completion might be fun over a weekend.


Looks like we're hearing more negative comments on ash for timber joinery...

Hi All,

Lets not have too much of a downer on ash. It is very strong and was the main timber used for wagon and even car chasis production until fairly recently. If kept dry it will last but like elm it is prone to bug attack all the way through. Though strong, ash is very springy and that is the main reason that it is not widely used in construction. The floor planks used to form the framing floors in The Weald and Downland Grid Shell building are all ash. Ash floors are good at preventing "tired leg" syndrome much bemoaned off by housewives who stand for long periods on a hard floor by a kitchen sink or table. I have found that many people believe that the only timber used in timber framed buildings is oak when infact many other timbers are regularly employed as well including elm, chestnut, hazel, alder, beech, poplar, birch, cherry, etc.

The reasons for large checks appearing is most probably due to boxed heart conversion. If a timber is halved or quartered then the timber is able to freely relax upon its self as it dries. When one runs a hand over most old tie beam faces the shrink back inverted "vee" profile on the halved face is easily detectable.

UK ash (Fraxinus excelsior) is not the same as the various other American ashes. I gathered some American white ash seed one spring morning on the common at Royalston, Mass. just as the snow had melted and I now have a number of those trees growing in my woodland. If nothing else, I have noted that the leaves turn a beautiful shade of crimson / purple in autumn.

Regards

Ken Hume

I worked in a canoe livery at one point, the nearby river had a couple of class 3's so I spent the slow periods rebuilding boats. I was out of ash at one point and had some red oak so I rerailed a boat in oak. It lasted one weekend and the client insisted (more than most) that he had barely smacked the rocks. Looking at the damage I agreed.

I had done some checking a month or two ago while sawing some ash. If you design for deflection, as Ken noted, that's its "weakest" property. For other properties I've compared it to our northern red oak.

I had a email conversation with a client a month or 2 ago while I was sawing some ash, this is an excerpt;

looked in my old Forest Products Labs "Wood Handbook" at the average clear wood strength numbers. When I think of splitting I think of shear or tension perp.

Tension perp in dry white ash is better than northern red oak, it is stronger in horizontal shear, higher bending MOR, slightly lower MOE, impact is identical, higher in work to max load. Ash also has greater side hardness and compression parallell to and perp to grain. I think those must be the key.

I think my anecdotes are wrong, it probably doesn't split easier, it simply will not crush out of the way if presented with an ill fitting tenon or too much glue in a mortise but it is in most characterisitics somewhat stronger than good red oak although a little less stiff. In the furniture presses we had basically unstoppable assembly power so when we split it we though of it as easy to split, it probably just couldnt absorb bad workmanship as readily as the other woods we used.

Which led me to look at maple, since they've had problems with the new maple ball bats breaking. It is anywhere from a bit to alot inferior to white ash for a ball bat. Makes me wonder who thought of using it. Hickory or locust would kick its butt.

Of course the biggest concern at the moment is how soon the slabwood will be dry enough to throw in the stove.
..................

I raised a hot blister on my circular blade while sawing that ash and had to go visit the sawdoc. He asked what I had been sawing, thought I had been in some yellow pine. I said ash and he said "of course, you got gummed up" he said the bigger mills keep a few poplar logs around and run one through occasionally to clean the blade back up. It isn't a pitch but it does gum it up.

For many woods this is the NDS supplement containing wood design values, no ash as I'm sure you've found;
http://www.awc.org/pdf/2005-NDS-Supplement.pdf

Tangential shrinkage is what causes most of what has been described. The high point of Ken's description is the quarter sawn section, radial shrinkage is half of tangential. As the face moves further from that area the grain orientation fades to closer to tangential and the wood receeds more and more, leaving the inverted V face.