Fuming OakSteve Smith
A colour change to a
rich chestnut brown
via the chemistry of fuming.
Throughout the ages, oak has been the timber of choice for British craftsmen. Whether it be a sturdy set of church gates or a great ship like the HMS Victory, oak has been highly valued for its strength and durability.
The slow grown, French oak we use at Classic Memorial Benches is rich in tannin (Quertannic acid). Tannin is a natural fungicide and pesticide and it’s part of what makes oak such a durable timber and naturally resistant to decay.
This tannin however can occasionally cause some staining on paving stones and the surface of the new wood as it is exposed to the outdoors and rain dilutes some of the surface tannin. This doesn’t harm the oak, far from it, and in a few months it usually washes clear however there are some steps we can take to reduce the possibility of it happening.
Firstly, the oak we use is slowly air dried over a number of years. This drying process causes the heartwood to become rock hard, less permeable to water ingress, and therefore less likely to release its tannin.
An additional step we can take is fuming the oak. Fuming is an age-old process that involves placing the piece of furniture in a sealed chamber and exposing it to strong ammonia fumes for up to two days. The ammonia reacts with the tannin in the oak and produces a very even, rich, and darker colour to the wood. It also neutralises the tannin in the surface of the wood making it less likely to react in the future when the bench is placed outside and tannin stains are less likely.
In the picture left, our Classic I memorial bench in the top picture has been fumed for 18 hours and the bench below is the raw colour of the new oak.
Whether you choose to have your oak memorial bench fumed or not, it’s important to keep the bench clean and well maintained. More information can be found on our aftercare page and of course you can get in touch if you have any queries at all regarding the care and treatment of your Classic memorial bench.