Anybody ever post this up for review before?
http://www.fiberglasssupply.com/pdf/vacuum/CONTOURKORE.pdf
Dsiclaimer: all info provided here without permission of author…
I happened to venture off there on a whim and found a very interesting quote…
Once all the balsa sheets are cut, they are coded for position, stacked (scrim side down) and a coat of resin is rolled on them as thinly and evenly as possible. This “hot coat” prevents the wet laminate resin from penetrating too far into the balsa during vacuum bagging. A gel time of 15-20 minutes is used to attain as rapid a cure time as possible; ideally, the balsa is left overnight to cure completely
These guys vacuum 1oz fiberglass mat to the outside of this ContourKore endgrain balsa laminate and then sealed with layers of glass over that…
Here’s smoe other interesting quotes:
The Olson 30 is built with a balsa-cored hull and deck. Though balsa is a sometimes ‘maligned’ core material, it isin my estimation the best, considering the strength-to-weight properties.
"Why not foams? We have tested synthetic foams extensively, but never put them in a boat. We found, in testing, that under point
compression loading, foams crack and fracture the skin on one side, as compared with the balsa core. A fracture might go all the waythrough a balsa/FRP sandwich, but it takes a lot more force to do so than with foam. The main difference is that if a balsa core isdamaged, you can pinpoint the area. Synthetic foam damage, on the other hand, is extremely difficult to pinpoint. On one side of thelaminate you may see a fractured gel coat, but on the other side it could look perfect. It would look like the simplest thing in theworld to repair, but when you look at it head-on (cross-section), you will see that the foam was totally sheared into two pieces."A balsa/FRP sandwich has amazing strength. We did impact tests on both foam and balsa core, with the balsa maintaining nearly100% of its structural integrity at the point when structural failure was resulting in the foam.
Hot coating and sealing the Balsa prior to lamming the glass to it hmmm…
Is this Bert’s secret i,e, building a Balsa/FRP sandwich under heated vacuum but basting the wood first to reduce the resin intake?
Anyway thought it was interesting as I’ve never heard this one before.
Everyone’s been talking about basting your glass job or spackling the foam closed… No ones talked about sealing the wood before applying the glass…
Comments from the iso-peanut gallery?