Tuesday, May 19, 2009

After two weeks of sturm und drang, it seems that the lamination problem is becoming clear.
Snediker found a source for the Aerodux-500 glue in England; they agreed to ship it to him. He had to pay the manufacturer to pack and ship it to him, since the uncured glue is classified as a "Hazardous Material", and it would have to be flown internationally, and brought through customs.
The package didn't come when it was supposed to. After two weeks of international phone calls, and post-event analysis of tracking, mis-shipping, and slow handling, it seems that the paperwork got separated from the shipment, so it sat in the UPS Boston terminal without being identified, waiting to be straightened out, for three or four days.
About a week after the shipment was supposed to be here, I strongly suggested we speak to Gougeon Bros about the folklore which said that white oak couldn't be glued with epoxy, and see what could be done.
Their engineer spoke with Dave, and admitted that there could be a problem with laminating bent frames. He said that the cause is not maladhesion, or any weird characteristic of the wood, but glue starvation in the lamination, caused by the force applied to the laminations required to shape the frame.
He suggested the following procedure:
Coat
semicure
recoat
cure
test
After hearing about this discussion, Andrew mentioned that he had also used large (quarter-millimeter) glass spheres mixed into the glue (although he didn't know of a source) or short lengths of monofilament laid in the glue, to prevent the same problem.