NidaPlast Panel for Sole

[bklake]

Edge. Don't do this. I pulled on the fabric trying to saturate it and ended up with this. Some grinding in my future.


Resin in the honeycomb.


The curve I glassed in.


Once fully cured, I'm going to put some "stingers" down, spaced about 20" apart to see if it is stiff enough for a sole. Right now, it is way more flexible and floppy than a sheet of 12mm ply. Should stiffen up once I glass in some structure.

According to the Boat Builder Central epoxy estimator, I got a 40%. Not bad for a first try with biax and 18 year old epoxy.

[bklake]

Refresher: I used 3/4" honeycomb and 12oz biax. One ply per side. MAS epoxy. Is it good to use for sole? Maybe.

The front of this has a very slight curve, maybe 3/8"-1/2" (8-12mm)over its 44" width. The back has a more pronounced curve 1 to 1 1/4" (25-32mm). With blocks at 20" spacing and standing on it, the front flexes a bit. The rear doesn't flex much at all. I used 20" because that is the stringer spacing in the plans I have. No creaking or cracking sounds just flex. The arch in the back proves that arches are stronger but it is probably too much for a sole.

The biax stuck to the scrim layer completely. The "green" glass that I wrapped around the edge did not stick at all. I was able to pull it off by hand without damaging the base layer which stayed stuck. While cutting the edge with a utility knife, I did learn that cure biax makes a really good rasp that is able to strip skin off knuckles very quickly. It was suggested to wrap glass tape while green. I did this with the cloth. It did make a nice edge but it didn't stick well and it pulled up glass at the edge. I'm won't do this with the ply layer again. It may work better using tape but it didn't stick well. The way I did it was just an experiment, a failed experiment.

The first layer of biax went on smooth and flat. I got a few bubbles on the other side. The barometric pressure was dropping due to an approaching tropical storm. With bare wood, this usually results in small bubbles in the epoxy. We have all seen that. With the big cells, there is a lot of air to expand. Bad timing on my part. Be ready with your favorite tool to pop the bubbles and keep it flat. A thickened coat on the scrim and allowed to gel then glassing may save some epoxy and make it lighter.

This combination is probably not enough for a sole at 20" spacing. I don't know if 17oz glass would make it stiff enough. Maybe 1" honeycomb would be better. Another layer of glass starts making it a lot more expensive to do. It took 48oz of epoxy per side with 12oz glass but there was a lot that soaked into scrim layer. It is possible to mold in compound curves, you can make some shapes that are more pleasing to the eye. I think Nidaplast panels are 2 layers of glass per side. They are much stiffer but are dead flat. No bending them to a shape.

Some of this is repetitive but this post is a summary. I need a scale so I can weigh the panel. I can lift it with one hand but it isn't feather light by any means.

[Fuzz]

From my little use of honey comb core I find it needs around 25 oz of glass on both sides to be really stiff. I feel like around 25oz is also needed to resist puncture. I am sure there is a sweet spot where core thickness and skin thickness produce the best bang for the buck but I do not know where it is. I would love to have core in different thicknesses up to 2 inches to test myself but at this point it is just a guess. I do know the commercial fishing folks in this area have fallen in love with the 2 inch core.