120 Roasts and Gunge

[Angela]

There is a build-up of sticky residue. There is no protection over the circuit boards; is that going to matter?

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And anyone else have a top with a twisted sense of humour?

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That's my skateboard ramp in the distance!

[kaffelogic]

There is a build-up of sticky residue. There is no protection over the circuit boards; is that going to matter?

That all looks pretty much as expected for over the 100 roast mark. You are right that the circuit boards do not have conformal coating. Conformal coating is not required for protection against this type of 'sticky residue'. Our circuit boards have extra clearances designed to improve robustness, and this is sufficient for their intended operating environment.

For others reading this post who might be inclined to remove the plastic top, it is preferable when you do so that you do not separate the plastic top from the aluminium roast chamber, but rather remove them as one part. There is a technique for doing this - please write if you would like instructions.

[Angela]

For others reading this post who might be inclined to remove the plastic top, it is preferable when you do so that you do not separate the plastic top from the aluminium roast chamber, but rather remove them as one part. There is a technique for doing this - please write if you would like instructions.

Please explain the technique; the tails to the probe are on the short side.

When I first got the thing and needed to dismantle to fix the motor mounts, I found there was no room for fingers to lift the heating chamber into the top housing because of tail length. What whizzy tools do you use?

[kaffelogic]

I do have instructions with photos in preparation, but in brief: the plastic top shrinks by virtue of annealing that takes place over the first 5 to 10 roasts. This tightens the connection between top and roast chamber. If you then break that connection it is very difficult or even impossible to get the rim of the roast chamber reinserted into the plastic - usually requiring replacing the plastic top with a new one. The technique for stripping the unit involves removing the front panel first, loosening the connection between roast chamber and element chamber with the fingers, and then lifting the roast chamber - still connected to the top - up enough to remove the back panel.

[Damian]

Hey Chris, is the plastic PLA?

[kaffelogic]

Hey Chris, is the plastic PLA?

The plastic is Nylon PA 66. PLA would be a more environmentally friendly choice, but the temperature tolerances pretty much dictate PA 66 in our case.

[Damian]

Thanks, when I read you anneal it and get some shrinkage, I thought of PLA. I was surprised if annealed PLA would handle 230+ deg C though.