Annealing in the oven - Don't (bother to) try this at home.

CandyFab Output + Ugly stick = ?

As noted on the list of questions and recently brought up again in the forums, it had been suggested at some point that it might be possible to smooth the rough edges of lower-resolution CandyFab sugar output by annealing it in the oven. The idea being that you heat it to the point that the structure softens enough to relieve stresses but does not yet deform-- slightly under the melting point. This is potentially a good method to avoid cracking. As a secondary effect, it is conceivable that the loosely attached material on the outside (the white fuzz) would preferentially melt, leaving an improved and (maybe) smoothed object, something like flame polishing. Well, that's the idea anyway.

In a household oven, this is a real challenge. As read with our (very good) pyrex thermometer, the oven temperature swings by as much 50 degrees when it's "at temperature." Yikes. So, we put a few of our objects to be destroyed, er, mini-docecahedrons on parchment paper, and into the oven they went. Actually, we cooked them one at atime. We put the cookie sheet in a cold oven and slowly raised the temperature, taking them out after half an hour. We took the temperature close to, but not reaching, 20 degrees below the melting point of sugar. And, as you can see in the picture of the two above, the effect was reproducibly less than stellar.

The loosely attached sugar on the outside of the models did melt, and flowed down the objects to form a puddle at the bottom. (The one on the right has been turned so that you can see the what the bottom puddle looks like.) Other than that, we observe (1) it did not result in a smooth finish (2) it resulted in additional caramelization/discoloring-- suggesting that the temperature was not as indicated-- perhaps just due to nonuniform temperature in the oven and (3) that the lower halves of the models look smaller than the upper halves, so there actually was bulk deformation occurring... meaning that we may not have even been in the annealing regime.

Conclusion? It's not obviously possible to achieve useful annealing under these conditions-- or possibly at all in a standard home oven. We may try again at a lower yet temperature. But, looks like this is one thing that we can add to the list of good ideas that just didn't work out.