WoodSkills Issue 02 - Page 72

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Apply an even layer of glue about half a millimeter thick to all but the top layer to be laminated using a roller or spreader. It can be easier to lay the layers all out, edge tape them down and apply glue to all of them at once. Then stack the layers and lay the top layer on. To stop the layers from sliding too unnecessarily in the bag, you can tape the sides loosely with a piece of veneer tape. Be careful to do this on edges that will not need to stretch over the former only.

Place the stack on the former and, again, tape down at the apex to hold it in place. Drape this with the plastic layer, place the topping board on top and, again, tape this down.

The whole lot is now ready to go into the bag. Once it’s sitting pretty centrally on the baseboard you can drape the former lengthwise with the extra breather fabric and trail this down to sit under the pump valve. This is crucial as it creates a link between the former and the vacuum pump without which the laminated section will quite probably be flawed if not ruined. I’d even suggest folding the fabric in two under the valve to give it a little more suction power.

The bag can now be sealed and the pump connected – how this is done will depend on the model vacuum pump being used. The pump is now turned on and the air is being evacuated from the bag,

This is a good time to use your hands to smooth the bag down over the piece and pull out any sharp creases or bunching that might be appearing.

The pump should reach 15psi within a few minutes. If this is not happening it will need to be remedied quickly. To find any leaks or unsealed areas, turn off the pump and listen carefully to locate any hissing sounds. Some duct tape should work to seal any leaks temporarily. If you can seal the leaks before the glue starts to go off, the lamination will not be affected.

The pump should be set for somewhere between 6-8 hours to allow the glue to set properly. As the noise can be pretty nerve jangling, my preferred option is to set it on a timer last thing in the evening or when machines will be running.

Applying glue to laminate layers using a glue roller