Kiln Dried Vs Air Dried

[Bryan Milham]

Gents,

Looking to pick the Hive Mind.

I am doing a small job for someone, and there is the opportunity for the occasional ongoing work. But he insists that the timber is Air Dried Ash as opposed to Kiln Dried.

He says it is more resilient (the work has to take a sideways shock loading) and Air Dried just snaps through.

Anybody met this sort of occurrence or happening before in Kiln Dried?

[GBF]

I don't like Kiln dried it always seems to be less easy to cut and a bit over dry and hard.

Regards George

[The Bowler Hatted Turner]

Basically the same as George said, air dried timber seems to have a little more resilience in it than kiln dried. But as far as the job is concerned I would worry more about the uniformity of the grain.

[seventhdevil]

Gents,

Looking to pick the Hive Mind.

I am doing a small job for someone, and there is the opportunity for the occasional ongoing work. But he insists that the timber is Air Dried Ash as opposed to Kiln Dried.

He says it is more resilient (the work has to take a sideways shock loading) and Air Dried just snaps through.


Anybody met this sort of occurrence or happening before in Kiln Dried?

after nearly a decade of turning skittles which need to stand up to exactly this sort of punishment i can say that the customer knows what he's talking about.

kiln dried wood has been through the kiln too fast these days and the lignin has started to be broken down by the process which ends up with a timber that may very well be nice and dry and be dimensionaly stable (relatively speaking) but it has lost any structural integrity compared to what it once had.

the wood becomes brittle and fragments or snaps rather easily and is useless for any sort of project that needs a good bit of impact resilient timber.

air dried won't get much further below 20% and the moisture retention gives the cells the elasticity required to rebound back into shape and stand up to the punishment whereas kilned wood has become too dry to have much elasticity left and will snap quicker.

i've used both kiln dried and air dried for my skittles and kiln dried doesn't hold a patch up to air dried timber and only lasts half as long so far as my skittles are concerned.



what use does your customer have in mind???

[Les Symonds]

Bryan....I believe that the problem with kiln drying is the speed of the process. My understanding is that in air drying, there is a slow seepage of moisture out through the cell walls, which causes little or no structural degradation. However, the rapid, forced evaporation which takes place in kiln drying causes slight rupturing of cell walls, which is why their elasticity is reduced.

Les

[Bryan Milham]

what use does your customer have in mind???

Steve,

He works in church belfries, there are many parts that need some degree of turning, this particular part is the Bell Stay, the rest that holds the bell just past the upside down centre when it's resting (not being rung).

[seventhdevil]

that's the upright bit connected to the headstock yes?


http://www.wdcra.org.uk/study/bellparts.htm

[Bryan Milham]

Steve,

yes that's the bit.

I'm no expert but talking to the guy, it's the bit that rests the bell when it is pulled just over the vertical. There is a second component to it that moved backwards and forwards (the slider in your image) on a pivot at the opposite end, so the bell can be rested from either side.

He says they sometimes break if it's rolled a bit hard, but much more so if it's air dried timber. There can be a couple of tons of Bell resting on it.

Actually that part is only a roughly planed section of timber, no turning involved, but it's because of this part, he wants air dried timber, not kiln dried.

I was surprised to find out just how many turned parts there are up in a belfry.

[seventhdevil]

do they not want to use a stronger timber like robinia as it is much better than ash.

if they really want stuff that won't break i can suggest a few exotics they could use???

what size is required?