WEEK COMMENCING 30 SEPTEMBER 2018
I had a great evening at the West Oxon Woodturning Association on Tuesday, another demo that went well but completely off schedule and all the better for it. Welcome to all the new readers who signed up on the evening. Now to the questions..
A caller this morning has been using our WoodWax 22 for a long time and is very happy with it (of course!) but wants something just a little bit more durable, and is going to try Microcrystalline Wax. Can this be applied over WoodWax 22 if he needs to? The short answer is yes, no problem at all. The long answer – you knew there would be one – is that in finishing it’s never a good idea to put a tough finish over a softer finish. Putting a lacquer over an oil for example would be a bad idea. Whilst Microcrystalline Wax is harder wearing – it’s more water and heat resistant – the coating itself isn’t harder; it’s still a wax after all. So that’s why it’s ok to do it this way round.
We often say that you should only ever apply one coat of Cellulose Sanding Sealer if you’re going to follow it with a lacquer. This is because the sealer is, in relative terms, softer than the lacquer and too many can coats can lead the lacquer to crack and craze. What though, we were asked, if you’re working on a very porous piece of wood that would benefit from extra sealing? There is a way around this. Normally after applying a sealer only a light denib with a fine abrasive is needed. If you absolutely have to apply more coats to build up the sealing properties then you’ll also need to be more aggressive in your sanding. Start with a coarser grit and work through almost as if you were starting on bare wood. The important factor here is to remove most of the sealer from the surface of the wood, so that it only remains in the pores. That way, the pore sealing will be achieved in several coats without building up a coating on the rest of the piece, avoiding the danger of the lacquer above cracking.
We’ve been asked a couple of times in the past about this Newsletter and whether it would be possible to produce an Index of topics covered so that readers could look for a product name and go straight to the relevant Newsletter(s). This could be difficult, especially retrospectively, but the good news is that the Search function on our website will search the copies of the Newsletters on there, in the text as well as the titles, so if you vaguely remember me saying something about Liming Wax (for example) you can search just that. It brings up ten results if you’re wondering (Eleven after I publish this!)
And that’s three questions already for this week, they just fly by don’t they? But there will be more next week, never fear – and we’ll see you then.