Questions regarding drying wood

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

LewisM

Established Member
Joined
14 Nov 2015
Messages
35
Reaction score
0
Location
Bristol
I recently stopped by a timber yard and picked up some ash, elm and cherry offcuts. The pieces vary from around 4x4" up to 6x6", and are each about 1 - 3 meters long.
They said that they were dry, but the warehouse / storage unit they were in was very open, so really it's more like they've been outside but haven't got rained on. I brought them inside the house to start getting the moisture levels down, and after a week most of them have a few small cracks near the edges, nothing major. The one big 6x6" has fairly deep looking cracks running all over it which I'll admit is pretty disappointing, but I guess for what I paid I really can't complain.

A friend also gave me some branches of holly that he'd just cut from his garden. They were pretty small so I only managed to get 3 pen blanks out of them, but I'm still looking forward to trying a new species of wood. As they were straight out of the ground they were soaking wet, so after milling them down to size I decided to try drying them in the microwave. A bit of googling followed by some zaps in the microwave and here we are, 2 days later with bone dry holly blanks that have barely cracked at all. I'm seriously impressed with how well this worked, I'll definitely be using this in the future.

Which brings me to my question - how should I go about drying out these big bits of wood? I don't want to cut blanks out of them only to come back a week later and find they've all cracked right the way through.
I figure there's 3 options:
1. Leave them full size and in the house for ~4-5 weeks, then cut them up into rough blanks and leave for another ~2 weeks, then just turn them down as I need to.
2. Cut them up, rough turn them then let them sit in the house for a few weeks.
3. Cut them up, rough turn them then microwave them dry over a few days.

The thing is I'm hoping to sell a load of pieces at the upcoming Christmas fairs, so I really don't want to have to wait 4+ weeks while the wood dries. That said I also don't want to cut them up into blanks only for the wood to tear itself apart...
Any suggestions on how to proceed would be appreciated.
 

peter-harrison

Established Member
Joined
25 Jan 2018
Messages
282
Reaction score
109
Location
Cambridge
The bigger the bit of wood is, the bigger the cracks. If you put a bit of air dry 6x6 straight into a central heated room, it's bound to split all over, especially as 6x6 usually has the heart wood running right through it and so the stresses have nowhere to go.
This is why your pen blanks worked so well. If you have a good idea what you want to make, and how much to allow for shrinkage and distortion, I'd cut it all up and microwave / etc it.
It's always good to seal the ends - I use leftover emulsion paint but for pen blanks you could dip them in melted candle wax
 

marcros

Established Member
Joined
11 Feb 2011
Messages
11,302
Reaction score
738
Location
Leeds
Be very careful with pen blanks. Depending on the kit, they are turned to 1mm or less in places which is glued to the metal tube. If slightly wet the pen will split soon after assembly. I would buy some pen blanks that you know to be dry, or you will ruin your reputation with customers. Save these few for a few months time.

I don't know much about other blanks, the small amount of bowl turning that I have done was with purchased dry blanks.
 

LewisM

Established Member
Joined
14 Nov 2015
Messages
35
Reaction score
0
Location
Bristol
marcros":3uetuewa said:
Be very careful with pen blanks. Depending on the kit, they are turned to 1mm or less in places which is glued to the metal tube. If slightly wet the pen will split soon after assembly. I would buy some pen blanks that you know to be dry, or you will ruin your reputation with customers. Save these few for a few months time.

I think as long as you're smart about drying things it should be ok. Once a piece stays at a consistent weight through a few rounds in the microwave it's almost certainly dry. Leave it indoors for another week to allow it to settle and I'd say the risk of it cracking is very small.
I'm more concerned with the big, thick pieces than anything else - getting them dry / stable quickly would be much more of a challenge...
 

CHJ

Established Member
Joined
31 Dec 2004
Messages
20,130
Reaction score
75
Location
Cotswolds UK
LewisM":3qqzin8x said:
…. I really don't want to have to wait 4+ weeks while the wood dries. ....

Sorry to say if you are aiming to handle any quantity of 'new' wood for turning stable pieces you will need to think in terms of months even YEARS not weeks.

The Turning Section Help and Safety Sticky has some notes on the subject.

I have timber that has been in store for 5 years that is still marginal for turning use and has to be handled with due care to avoid it splitting or at best distorting.

The old adage of 1 year per 1 inch thickness for air drying of planks and slabs is not over cautious, logs can take considerably longer dependant on species.
 

Latest posts

Top