WEEK COMMENCING 24 SEPTEMBER 2023
Greetings from the poolside! Yes, I’m still on holiday, but don’t worry, I’ve prepared this Newsletter before I leave and programmed it to be sent out today. (This is very confusing, I feel like I’m writing in present and future tenses! How does Doctor Who manage?*). As I’ve been out of the office now (when you read this) for a week, I haven’t seen the questions that have come in. Hopefully there will be some notes for me, but in the meantime I thought I’d do a follow-up to my ‘Phew, What a Scorcher’ Newsletter from a few weeks ago. I hope you won’t mind.
So, a few weeks ago, with my usual bad timing, I discussed the effect of hot weather on finishing. We did have a few hot days after that, but now that we’re nearly in October the weather is changing, nights are drawing in, and, to put it bluntly, it’s turned cold!
Co-incidentally, this is also the time when turners start venturing back out into their workshops to start creating (although I know some never stop during summer either!).
Just as extremes of heat can affect finishing, so can cold weather. Quick drying products will often be just that little bit slower to dry, although the solvents in products such as Cellulose Sanding Sealer and Melamine Lacquer evaporate at such low temperatures that it’s hard to notice. Some of the oils will, however, take a little longer to dry.
The viscosity of products will change as well; they will become slightly thicker, so spreading them evenly can become harder. A bit more time and patience could be required here.
I was talking a few weeks ago about how a paste wax (such as WoodWax 22) can get harder with age, and being cold can have the same effect. This means that it’s harder to spread, and can result in a too-thick coat being applied which then won’t shine up properly. The answer here (other than waiting for a warmer day), is to use a slightly coarse cloth (such as an Orange or White NyWeb) to apply the wax, as this will held spread it more thinly.
The real problem with cold weather is that it can also bring a damp atmosphere with it, and this is particularly problematical for finishing. If the timber itself is damp, this can cause poor adhesion for lacquers, leading to a disappointing finish.
Lacquers are particularly susceptible to the damp, especially when sprayed. They can pick up particles of water from the air, which become trapped within the lacquer – and that’s not a good mix. Moisture will cause the lacquer to exhibit white patches, where the water content has prevented it from sticking to the wood properly. There’s little that can be done to fix this once it has happened, so prevention (i.e. warming the workshop or just waiting for a warmer day) is the best option.
But the real problem the winter brings is the danger of frost, which can destroy some of our finishes if they are exposed to it. To be specific, End Seal and the non-aerosol versions of Acrylic Lacquer and Acrylic Sanding Sealer, all of which are water-based. If these are damaged by frost then I’m afraid it’s game over for them. Allowing them to thaw out isn’t sufficient, they will not return to their original state. (If you’ve ever had a can of emulsion paint freeze, you’ll know what I mean). So, if you have these products, do what you can to protect them.
Curiously, Tung Oil will also freeze to a solid block, but will thaw back to it’s normal state.
And that’s everything for this week. I’m back in the office at the end of next week, and I’ve asked my team to keep a note of any questions that have come in during my absence. I’m sure they’ll have answered them already, but I’m always keen to share them with you!
I’ll see you in, well, a week for you, and two weeks for me! Now, if only I really did have a TARDIS…
*The answer to that is that the script is full of fun but nonsensical gobbledegook, so none of it makes much sense!!