Wet blanks

[chrisb691]

Okay, so this is a convoluted question...so bear with me please.

A few months ago, I turned an Efusa Burl blank, and the pen was quite stunning. Trouble was, with a few days it was wrinkled like a prune. Found out, via the forum, that the timber was still wet. So I left them for a few weeks, and then turned another one. It took longer, and it wasn't as bad, but the pen still dimpled. At this point I decided to have a go at freeze drying. So into the freezer for 3 days, then into the fridge. 2 weeks has passed, and I was going to try turning another one. Just to prove it was now dry, I popped in the microwave for a minute. When I took it out, it was too hot to hold, was very wet on the outside, and steaming like all buggery. So, obviously, freeze drying is an oxymoron, and did zilch.

I'm about to make up a Sierra set, for a birthday present, and I don't want them wrinkling down the track. I set a Brown Mallee blank, bought at the Melb WWS, in the lathe, and started drilling. Drilling was going fine, but as I got further into the blank, I noted that the drill didn't seem to be clearing properly anymore. I pulled the drill back, and sure enough, the shavings were packing near the front of the drill. Not only that, but it was plainly damp. Finished drilling the first blank, then did the second one..same result. Decide to pop them into the microwave for 30 secs, and sure enough, they came out quite warm. So now I intend to continue the Microwave/cooling cycle, until they don't heat up any more.

I told you this was going to be convoluted, didn't I. But here we are at last, finally getting to the question. :)

I refuse to sell, or even give away, pens that are going to undergo surface changes (wrinkling), some time after the recipient takes them. I struggle to believe that I'm the only person around, that is having this issue. So this means, that you guys must be doing something different to me. So how are all of you handling your blanks?, and who else is having a similar problem?

[DJ’s Timber]

Any blanks I get that I think might be still green get put away. Some of the blanks that I turn now have been stored for a few years.

I also buy blanks from a guy I know who I trust and he tells me which are dry or not

I have just got myself another mircowave, so I will be experimenting with m/wave drying soon.

[Skew ChiDAMN!!]

Just to prove it was now dry, I popped in the microwave for a minute. When I took it out, it was too hot to hold, was very wet on the outside, and steaming like all buggery. So, obviously, freeze drying is an oxymoron, and did zilch.

Not exactly. The idea behind it is not to dry the wood, but to cause cell walls to rupture (ice expands) so that when thawed and turned the shrinkage is reduced. Works better on some timbers than others, but I don't bother effing around with the method. :rolleyes:

Instead I microwave... which works on basically the same principle (steam expands) but is much, much quicker. I won't nuke a pen-blank though, or timber that's needed for an important project, as I believe it also weakens the wood to a degree and can cause later problems such as splitting. I also believe that it means the timber will also absorb moisture more quickly in future... which can lead to movement issues.

I only nuke green wood for throw-away jobs, so I can have a play and get an idea of how the timber will look when turned. If it turns really nicely when nuked, I may do some green turning of other blanks and put them aside to dry properly before being finish turned.


I refuse to sell, or even give away, pens that are going to undergo surface changes (wrinkling), some time after the recipient takes them. I struggle to believe that I'm the only person around, that is having this issue. So this means, that you guys must be doing something different to me. So how are all of you handling your blanks?, and who else is having a similar problem?

I'd say that most of us are using purchased blanks that've been correctly dried. :D So it's not as common a problem as you may think.

I think your real solution will be to make a drying cabinet for pen-blanks and be patient. 6 months is nothing compared to 4 or 5 (up to 10) years for bigger blanks. Don't forget to mark 'em with starting dates! ;)

Personally I also dry a lot of my own; a drying cabinet is really handy for quicker throughput. Mine's just a 20W 240V light bulb in the bottom of a box, so the temp inside the box is always a couple of degrees above outside ambient temp. But I also have a lot of blanks cut to size and stacked on shelves (with stickers between to improve airflow) which will b e left there for a couple of years before seeing use.

ie. The long term answer is: Patience, my friend, patience. ;):D

[DJ’s Timber]

Drilling was going fine, but as I got further into the blank, I noted that the drill didn't seem to be clearing properly anymore. I pulled the drill back, and sure enough, the shavings were packing near the front of the drill. Not only that, but it was plainly damp.

This dosen't necassary mean it's damp. It could be that the timber had a high resin or gum content and the heat from the drilling softened the resin or gum resulting in a damp feel and drill backing up with shavings.

I have drilled burls and other hardwoods that I know are dry and have this happen. You must keep pulling the drill in and out regardless of species or how dry or wet it is. The further in the drill is the harder the shavings have to push to clear the drill and start blocking up and getting hot

[Skewpid]

Hi Chris . .

I tried my first 'nuked' timber only a coupla weeks ago.;) . ..

After a quick trip to Carb a tec, I picked up a block of Tas Blackwood and a block of Sass . ..

Upon arriving home, I discovered that they both were still very moist . :mad: .

So .. as the experimental bloke I am, I thought I would try something .:rolleyes: .

I just did a quick slice on the bandy and produced 6 pen blanks from each block. Over 2 nights I just kept throwing the blanks in the microwave (3 at a time) wrapped in some kitchen towel. .. I just kept doing that til there was no more moisture coming out. (approx 6-7 nukes each at med-low for approx 3-5mins) Then left them for a coupla days airing in the the workshop.

I turned both the Sass and the B\W about 2 weeks ago now and they are still as shiny and stable as the dry ones.:)

Now .. I coulda been arsey with this, and may not work on all timbers, but certainly saved me about 2 years of waiting round for the block to dry:D

[dai sensei]

ie. The long term answer is: Patience, my friend, patience. ;):D

What's that:confused: :D

Seriously though, if you drill the blank out to suit the mandrel (not the sleeve), then rough turn it down to 2mm thick and leave it on a nail it will dry faster (from 2 faces).

If you go the nuke way, don't over nuke it, it wil only crack from the inside. Gently is the way, smaller more often zapps are better, wipe down with cloth and cooling between goes. I only nuke if I want it within a week.

Freezer does work, but takes more than a few days. Just leave an unwrapped piece of meat in the freezer for a while and see how it dries out.