Vacuum clamping system

[tonyfoale]

Christophe,

Your work is of a high standard as usual. I sometimes use vacumn bagging when moulding carbon fibre composite. With hand layup it is usual to have too much resin in the layup and vacumn bagging can squeeze this out. The pressure requirements are lower than you would need for veneering and for simple shapes I use a shopvac to provide the "vacumn". I find that once I suck it out I can leave it and remove the shopvac. As long as the pressure is applied up to the time that the resin starts to cure then slow leaks are not important.

Click to see full size.

The first stage just after the layup is to fit a perforated plastic sheet on the non-mould side. This allows the excess resin to ooze through into an absorbent layer (shown above, and the plastic stops the absorbent material from sticking to the work. I cover that layer with a sheet of non-perforated plastic sheet and then some soft plastic foam to even out the pressure on the work.



This shows the final bagging, after being evacuated. This a simple near flat item for the bottom of a petrol tank and this lends itself to using a vacumn bag sold for compressing and storing clothes. They work very well for suitably shaped and sized items.



The mould and the rough side of the tank bottom, there are a few creases but that is unimportant because it is not seen..