UK’s 78 SN

There is one test I really wanted to do but not having any foam in my shop I can't.I noticed a slight curvature in the floor and the side of the boat along with cracks all along the bottom and sides where foam meets hull.Most people say its from the floor breaking away from the hull and the side flexing.I think foam expands when it takes on water in turn forcing the hull outward past its cracking point.If a person took a block of foam and covered it with resin on three sides you could emerse it in water and see if the expansion causes cracks.

Will see if I can do some of the other tests, as I found the new foam has sunk over time in cold water will measure how much, just a guess but could it be happening to some newer boats giving a soft floor ?

Not much done just back in today, I think some of this cold weather has come across it been as low as -10c here from midd Dec and no sight of it changing.
Have been trying my hand at tig welding and there is a knack, as yet I haven't got it yet.
Tried this out to bend the bronze bar for the front keel lift just stuck it in our waste wood heater for a while.

This foam stuff is very interesting, just noticed it. Nice work Roger!

I'm finding this experiment pretty interesting. I was wondering if you thought about a test using new foam with one cut side coated with epoxy or epoxy/glass? since the cut side is up when using foam, its covered in glass. There really isn't a cut side of the new foam directly exposed to water once installed.

uk1979 wrote: Hope my little tests can help others decided what’s best for there needs.

Well, that's exactly what its doing for me. I'm still leaning towards new foam for mine (much to the chagrin of other ccfan members I'm sure) so this little experiment is really giving me good information to go by. I almost dug into it this winter but have decided it can wait one more season. Glad I did, its darn cold here too.

Roger, you're quietly becoming a legend around here.

Greg no legend here the thing about this site is what you learn on it, as its been said before the older I get the more I realize how little I know,with all the great input on here and idea's, looking from a different country you are shown how its done there which is often much different, that can lead to a new train of thought and a new way forward and to learn something new.

These days it all about celebrity chef's, I think we are all chef's knowledge is our ingredients and its how we mix them to come up with great repair's/Idea's.

What a great cook book this site is.

Thanks for your post Greg the only down side is some of the great materials you guys have in the US that we don't which is a real pain.

Update on my foam in water tests and outside freezing then warming for 3 hours, water temp kept at warm only.

New type foam dry 46.7g with a cut face 6 wk + 2 wk outside in freezing weather, underwater now 70.3g has 25.8g of water soaked in and is up by 2.2g this 2 weeks.

New type foam block 6x6x6in with skin dry 191g 5 wk +2wk outside in freezing weather, underwater now 202.5g has 11.5g of water soaked in and up by 2.6 for 2 weeks.

Foam like pool noodles dry 11g 5 wk +2wk outside in freezing weather, underwater now 15.9g has 4.9g of water soaked in and no change for 2 weeks.

Original Foam dry 42.7g 4 wk +2wk underwater now 98.1g has 55.4g of water soaked in and no change for this 2 weeks,but to get the weight I had to pick out all the small edges that had broken off after freezing.

Also took the measurements of how much the foam block had sunk on the face that had been down in the water,all sides had sunk a bit but this side had sunk the most by 3/16 to 5/16, but the skin had kept its size of 6x6x6 in, will now see what freezing and heating will do.
Now after freezing outside has sunk much more and skin has begun to delaminate on edges, has sunk to 1/2 to 5/8 all sides have sunk see picture.




Will now stop testing all above have now coated a new type foam block in epoxy & cloth leaving one face cut/open and will soak under water and freeze also cut some old type foam which I will do the same but coated in polyester & cloth.

Thanks Keegan for your input,yes I'm sure the freezing along with the wood swelling up as it soaks up water overtime are the culprits for cracks in the stringer system.My small tests may not show much when I freeze as I think you may need a large amount to get the pressure to crack the fiberglass.

Few things I got done,
Exhaust mounts and extra mounts for the platform.


Repaired the bow hook as mine had the nuts pulled through the glass where it had been over stressed, and only small washer used.



Then shaped the 10mm glass and bonded in with thickened epoxy

Then a layer of biaxial overlapping by an inch then another layer of 10mm glass with biaxial over lapping by an inch,finishing off with a layer of 5mm glass,then biaxial and final coat of quadraxial.



Made the new bow lifting mount out of Silicon Bronze and S/S

Looking top notch as usual!

Wow now that's a tad bit of over kill there and a ton of extra weight in the nose.

It is pretty though and will be around long after all of us!

hope that the threaded rod is grade 8 but I'm betting it's standard S/S and the weakest link too. Doesn't make much since building all the extra support just to have the threads pull out.