Blue mould staining???

[Pete Bannister]

Alec

I think we agree on the matter. The object of my postings was to flag up the need for real awareness when embarking on the pesticide road. Just because you can buy it off-the-shelf somewhere can engender a sense that pesticides/biocides are 'safe' or are a universal panacea.

I was very interested to see Osmose make forays in the industrial heat treatment of softwoods some years. However, they took it down the oil impregnation path and came up with ‘Royale’. As you will know, Acetylation is now commercially viable (Accoya) and I hope this heralds a major positive step forward. I’ve yet to have a play with any acetylated timber though! Until Ive done that, I'll be a tad cagy about specifying it I guess

cheers

Pete

[Rob D]

Some serious heavyweight posting going on here!

 

 

But very informative thanks

[agg221]

Alec

I was very interested to see Osmose make forays in the industrial heat treatment of softwoods some years. However, they took it down the oil impregnation path and came up with ‘Royale’. As you will know, Acetylation is now commercially viable (Accoya) and I hope this heralds a major positive step forward. I’ve yet to have a play with any acetylated timber though! Until Ive done that, I'll be a tad cagy about specifying it I guess

cheers

Pete

 

The two approaches you mention above have thrown up some issues recently.

 

The first is the recent EU volatile organic content (VOC) legislation which came into force in 2010. This has, in effect, made the use of any organic compound with a boiling point below 250degC challenging to say the least. They're not banned, but the controls make it very difficult to apply them, particularly in volume. We were initially looking at systems based on a low toxicity organic solvent and had to change approach as feedback suggested that end users simply wouldn't introduce a new technology based on it, in part driven by the current legislation and in part by the fear that an extension to the legislation would make it rapidly obsolete. Essentially, anything fundamentally new now needs to be water based. A slight aside, but relevant, is that proper 'Cuprinol' (as in copper-oil, originally copper naphthanate in turpentine but latterly the octoylate in petroleum distillate) wasn't banned - it was withdrawn as the manufacturers couldn't justify the £40k annual fee for its registration as a biocide. This is another issue in introducing alternatives which work on a biocidal approach.

 

Acetylation has shown very good results with regard to durability - but has some adverse effects on the cell structure, most notably the timber becomes signficantly more brittle. It also changes both the appearance, which becomes muddy brown, and the smell, which becomes vinegary. It's also only effective on certain species, particularly radiata pine, so its uses are limited. This is very convenient for converting a low value, low durability species into something highly durable, but the cost of the process at present puts Accoya on a par with high durabilty hardwoods, so the benefits are mostly lost except for very high end painted joinery, mostly window frames, where the main benefits are easy machinability and high dimensional stability, the drawbacks being less signficant in these applications.

 

And yes, I think we agree, although the original poster may be beginning to wish he'd never asked! (hopefully he's got something useful to work with from the earlier posts)

 

 

Alec

[Pete Bannister]

Alec, I don’t want to derail Rowan's thread too much here, especially because its an interesting and worthy subject matter. However, your point regarding the withdrawal of (eg copper naphthanate) pesticides because of the cost UK registration is apt. Came across this recently when I was looking into the use of Armillatox. Its been withdrawn for the same reasons but is marketed instead as a cleaning agent, apparently thereby circumventing the legislation.

I take it you're in timber production?

 

cheers

Pete

[morten]

Hi Rowan, you're talking about conifers and so the blue stain (if its blue stain fungi and not iron stain) would be associated with the sapwood. In conifers, Ceratocystis spp. are the usual culprits.

Pete

 

The staining, that will only occur in the sapwood, can be vastly reduced by felling before the sugary nutrients are present in the wood (i.e. october - april, depending on climate).

That, and plenty of ventilation of the cut timber is the cheapest, easiest and most effective means of avoiding blue stain fungus.

[Pete Bannister]

some excellent additional advice from Morten.

cheers

[agg221]

Hi Pete, no I'm not in timber production, I'm in contract R&D - we're the ones currently developing the alternatives. I take it from your earlier comment that you're on the building surveying/remedial treatment side?

 

Alec

[Rowan the Bruce]

And yes, I think we agree, although the original poster may be beginning to wish he'd never asked! (hopefully he's got something useful to work with from the earlier posts)

Although it is a new subject for me to delve into, learning is the key to perfection. Some really useful tips and as the pine is to use as flooring for a kids playhouse I'm not too concerned with the asthetics of the wood this time. I am the type of person (bloody hippy) who uses chemicals, other than petrol/diesel in the kit, as little as possible so using a kiln and milling at favourable times is preferable. My lack of space is an issue and warm wet cornish summers too. Currently i have an entire trunk of Crytomeria stacked in my attic (hope the landlord doesn't read that!) seems like a good place to dry stuff, dark, air flow but warm. Thanks for the posts.

[Pete Bannister]

Hi Pete, no I'm not in timber production, I'm in contract R&D - we're the ones currently developing the alternatives. I take it from your earlier comment that you're on the building surveying/remedial treatment side?

 

Alec

 

Correct Alec. Bin over 25 yrs at it and its obviously showing! I’ve been with H+R E. I. for over 10 yrs doing building pathology. My interests in arboriculture is amateur and for someone who gravitates to timber (dead or alive) and its parasites there are some interesting observations on mycology to be had on this forum

cheers

[TrollSpiel]

Anyone know if the above borate solution is normal borax powder with water and what the ratio it says 5% for woodworm etc so maybe thats about right?

Order Woodworm Treatment Products - Boron based Woodworm Treatments

Although that seems a bit pricey compared to:

intralabs | Borax

 

 

Not sure if this post is still of interest to anyone - but after a day of looking into the science of borates...

 

I didn't want to fork out a small fortune for the "reissued repackaged" (mozza) product from this [top] company, they're a bit cunning about how they advertise it.

 

Great products (I hear) from Wykabor - again, at a cost for 5kg.

 

So here are the two chems they use in their products, with a few minor tweaks amounting to little it seems...

 

To prevent fungi and insects attacking structural timber, preservative chemicals are used. Boric acid (H3BO3) and borax (Na2B4O7.10H2O) are used to protect internal framing from attack by insects such as borer.

 

Both supplied really quite cheaply from the lower link of this mans original post.

 

After spending a grand on gear this week alone, I think I know the option im using!

 

Hope that's of any use to anyone who wants to use borates in the future.