The shape is imported as .STL in Vcarve for work with our brand new the ShopBot:
A first large tool is used to save time (still more than 20min), and then a second thiner tool is used for finition:The final shape is smooth, and does not need any further work:
The shape obtained is first recovered with a polyethylene film (food conservation film does the job) to prevent the resin to stick to the shape. Then paraffine oil is spread on the film to make separation easier:
I followed the instructions on the bottle, using a scale and the weight ratio between resin and hardener 1:.47 (rather than the volume ratio 2:1): Initially I prepared only 32.3g of resin (+15.2g of hardener), but it appeared in the next step far from sufficient. I therefore prepared a second amount of resin (50g+23.5g).
The assembly is finally put into a vacuum bag (for clothes storage), and a vacuum cleaner is used to remove the air:
It is important to clean rapidly and carefully the tools, especially brushes, before the polymerization; otherwise the brushes are to be trashed. However, it is not easy to find information about the proper solvent. (CH3)2O works, but this produces a large amount of secondary chemical waste, that has to be managed properly...
Or just dispose the brushes...
The composite shape is glue to the wood-shape because the polyethylen film was not tight enough. Next time, I will completely wrap the wood inside the film. It is difficult to separate the shape from the wood:
Here is the final result: