A spiral-effect bowl technique follow-up

[willstewart]

A new bowl with a steeper twist as implied in the previous posting, and some tips (eg do not use Cascamite for this!)

[Bryan Milham]

Like you I definitely prefer the increased spiral effect.

Don't stop now, you are on a roll.

[The Bowler Hatted Turner]

Thanks for this, very interesting. I like the effect of the second one more, at the risk of sounding rude(which I do not wish to be) would Cascamite work if you were to work a little quicker?As sometimes it can go off very quickly, especially when it is warm.

[willstewart]

Bowler-hat - not rude but I did work pretty quickly!  I am not sure of the real problem, I have used Cascamite very satisfactorily before, for example for making stacked-alternate-colour-veneer blanks for pens.  But these are clamped of course so any wood expansion present would not be an issue. I am inclined to think that the moisture in Cascamite is more immediately available to the wood than that in Titebond but that is just a guess.  I have (see new post today) now tried an epoxy and this does indeed give no-feel joints at the veneer.  But it soaks into the wood a bit and leaves a faint darkening mark.

[The Bowler Hatted Turner]

You could be nearer the mark than you think by saying the wood could take up the moisture from Cascamite quicker. Freshly mixed there are bound to be molecules of water that remain unmixed so that could be the problem. I used to use Cascamite all the time especially when I needed the stiffness that it gives when fully set ,as laminated veneers as you said,I also tried Tightbond II but have found that the good old fashioned white glue is just as good as any.

[willstewart]

OK - really the last word!  An example almost as good as the original with a mid-tight spiral in ash.  The wider red bands cf the original go with the tighter spiral (and thus the angle to the surface). This actually used the original bandsaw blade with a little sanding to open the kerfs because this gives a tighter fit, and epoxy as a water-free glue. There is no 'feel' to the veneer bands in this example. It is a little deeper and a little thicker (5mm) than the others. Tips:- 

This used 50-60 ml of mixed epoxy. Previously making up 120ml of epoxy (100+20) just worked but the residue had thermal runaway.  So this used two lots of 30 ml (25+5) made up in the little foil containers from individual apple pies!

The jig, as can be seen, has the bowl edge resting on its base for additional support to stop it flexing in the saw.  This is helpful - a small sacrificial wood piece on the jig base can provide this if needed.