Experiments with Laywoo-d3
I’ve just been playing with Laywood and I thought I’d share my what I found as there doesn’t seem to be a lot of real world experience type information about it on the net. The photos show one of my prints of http://www.thingiverse.com/thing:1283 at 1.25 scale. It stands about 5.5cm to the top of the back, 7cm to the tip of the ears)
Is it really like wood?
One thing is for certain, considering its 3D printed, Laywood is a pretty good approximation of the real thing. I noticed I needed to print a few perimeter loops (3 or more) to make it hard like wood but other than that not only does it look like wood but it even smells like it. The addition of tree rings by varying the temperature with the use of either one of the slicer plugins or the standalone python script ( http://www.tridimake.com/2012/10/shades-of-brown-with-wood-filament-via.html - shown here) makes it even more realistic. (Without the rings it looks a bit like MDF but not quite).
I’ve also done some experimentation with sanding down and wax/varnishing a couple of test prints. At that point it really starts to get hard to tell if its real wood or not, depending on your skill you could easily fool people I think. A quick word of advice for those of you thinking of sanding down your prints, when you do go easy with the paper and practice on some failed prints first. The reason being is if you sand too fast it heats the material up which unsurprisingly starts to melt and you get a horrid mess. You really don’t want to see my first attempts with a Dremel 
Whats it like to print?
“Challenging” but not for the reasons you’d expect. Mostly you treat it like PLA but go a tad slower. On my Mendel90 I’m printing with 3mm filament onto plain glass (it sticks quite easy) at about 25-35mm/s. For models without tree rings I’m running at 195c.
At this point everything sounds fine right? …well the issue is depending on your setup it appears to clog the extruder quite easily. On my J head I repeatedly had to stop the print,
back the filament out, snip off the end and try again. I’ve heard others with much worse horror stories including wrecked hot ends but I never saw any of that which is perhaps a testament to the quality of a genuine J head.
This clogging issue may not affect everyone though; reading around it seems like it is closely related to nozzle diameter. My Mendel is a 0.4mm and to be honest I think I agree with the others that are saying you really need a 0.5mm+ to print reliably (if you have 0.35 I think you probably need to get a bigger nozzle before you even consider it). I got away with using my 0.4mm but it was a bit hit and miss, although to be fair I solved a lot of the issues by jacking up the layer height to 0.3mm. Interestingly enough the increased layer height is no where near as much of an issue as it is with other materials as it seems Laywood naturally smooths out some of the layers and the others become a feature.
Whats the rigidity/strength like
When you first print Laywood it’s a little soft and squidgy. My recommendation is you don’t mess with it during this stage. Its tempting to try and pull it straight off the glass straight away but this will wreck the print, give it a good while to cool down properly then it starts to harden up. Also as I mentioned at the start, if you want it to feel solid like wood give it a good few perimeter loops, I found 3 or 4 to be a good experimentation point, below 3 and its still strong but feels a bit like cardboard rather than wood.
There is one gotcha though which I found particularly frustrating on this particular model. The tree rings effect whilst spectacular requires you to vary the temperature quite dramatically. In the photos below this is effect is achieved by varying between 190c and 240c. Those of you with experience will know that this will have a dramatic effect on the strength of a print and laywood is no exception. The darker rings appeared to pose significant weak points and whilst the body was large enough to be solid and unaffected the feet were extremely fragile at these points. As you can see the front right leg broke off and I had to use a small torch to melt it back on again for the photo.
Summary / tl;dr
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Yes, in my experience Laywood really is pretty amazingly good at pretending to be wood. Add some tree rings and a bit of varnish and I think you could easily fool people.
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If you want an easy life you really need a 0.5mm nozzle because it tends to clog smaller nozzles.
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At a constant temp its reasonably robust (although not as strong as regular plastics obviously) but if you want to do effects like tree rings avoid delicate objects like the cat in the example because the temperature changes cause weak spots which result in small cross sectional areas being exceptionally weak. To solve this you could either scale your object up or print something inherently more solid like a box, or one great example I saw, a gear knob. This issue doesn’t seem to be a problem with a constant temp.
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I like it, its not a replacement for PLA or anything like that, but use it in the right application with the right settings/nozzle and great effects can be achieved.
Hope this is helpful 
For me it seemed to break just above the dark bands but it could well have been the change from high temp to the cold temp that did it, so you may be right! I struggled to work out exactly why it was breaking but what you say makes sense it could be under extrusion from being too cold. I’ll try upping the minimum temp and trying again. Thanks for the info