Video: Why Are Woodturning Blanks Coated in Wax?
When you shop for woodturning blanks, many of them are coated in wax. Should you scrape off the wax before turning? Leave the wax on the blank?
If you treat these blanks incorrectly, you could end up with a cracks and checks. Rob Johnstone explains why many woodturning blanks are sold with a wax coating and how to work with those blanks.
Rob Johnstone: Turning wooden bowls is one of my most enjoyable woodworking pastimes. Rockler sells a wide variety of ready to turn blanks and a huge spectrum of species. That's what I want to talk to you about today. Now, if you purchase a that's covered with wax, like this one here, chances are it's green or unseasoned wood, which is great because that'll mean it turns like butter. It's important to keep the wax on the blank to avoid cracking. In fact, it's best practices to use a wax blank reasonably quickly.
Why am I scrapping all the wax off of this block? Well, we're going to do a little experiment. I'm going to remove all the rest of the wax and we're going to put this block into a bucket of desiccant to dry it quickly. It's the same thing as if you were to scrape the wax off and put it on your shelf for a few weeks. There it is, I've scrapped almost all of the wax off of this thing. Now, it's just raw wood. I'm going to stick it into the desiccant, wrapped it up, sealed it in, check back on it in a couple of days.
We're back. It's been a couple of days. Our block has been in the desiccant, scrapped free of wax. Let's see if any cracks have formed. As the desiccant absorbs water, it turns from blue to pink. As you can see, when the water left the fibers, these cells collapsed and that caused shrinkage and now we've got cracks in the wood. Our experiment was, I guess, successful because we got some cracks.
That's exactly duplicating what would happen if you scrape the wax off and set it on a shelf in your shop for a couple of weeks or a few months, which is why you should leave the wax on and turn your green blanks reasonably soon. I hope this has been helpful and informative to you. I'm Rob Johnstone. Thanks for watching.