No wrong when hit HARD HARD it will yield OR transfer the loading to a larger portion of thi inside lamnate .where The Balsa will Fail! How do you read cracking Gelcoat into that ? So you would rather have a failure instead?

Here is a very old Airex boat.

http://www.youtube.com/watch?v=esxxtLg8qJ4

Somewhat similar boat (first Quad sportsfisherman I've ever seen) but I guess you can envision what it might look like running into a tow cable from this video:

http://www.quadzeus.com/media.html

Steve- what the lab tested isnt "my wood". Nor Skaters, Schiada, Sabre, Lavey, Eliminator,Howard etc. etc. etc.

I've never seen non scrimmed balsa used in a core. How would non scrimmed balsa follow the shape of a hull?

We use labs all the time in my industry when they test they always post their name in a lower third on screen and state each manufacturer being tested along with the model number and date of material acquisition.

Ive never seen a Lab use a open locked stanley tape measure as a primary measurement tool.

I found Gurits test data on corecell.

Here are the #'s they post. You guys can all read em.



UD

Fascinating dialogue........

IMHO this is kind of like chocolate and vanilla...different strokes for different folks. Steve is probably the best foam core based builder around and has proved that over the years. Peter is the best performance boat builder on the planet and likewise has an amazing history.

My take is that foam core is wonderful in low surface impact applications, but repeated ballistic cycles tend to constrict the core. This leads to skin flex ( the natural result of the "bending" that Steve alludes to) and subsequent separation, followed by delamination and failure. Balsa , while certainly not perfect, is a better choice in these conditions. On the other hand, decks, bulkheads and other non impact areas are much better suited for foam core materials. Steve will disagree and certainly provide contradictory data, but if it were my nickle and my boat bottom, I would spec balsa on all running surfaces.

No disrespect intended towards Steve, as I believe he can build a foam cored boat that will withstand much more than most other builders and he is a genius at producing craft which limit impact levels through design and light weight.

T2x

Numbers ?? so what what do they really mean? Here too continue:
Uncle once again you cheap shot the discussion, the testing was done at Sigma Labs . The numbers are just that with the Plastic cores they do not indicate Failure Got it ! only the material moved and that was marked as it's physical VIA the ASTM Methods Now I just prefer the nasty moment of Inerita/Panel Beam Deflection Via any Extreme and Severe loading too be just that and not a Failure Point! Are you with me?? NON scrimmed Balsa LOL Uncle I will do another post.

No cheap shot intended - only observation.

Look at it objectively, my data has posted sources.
Actually "I" dont have any personal data,
I just copy data from the guys that make the product.
Until you answered sigma labs- how would I/we know?

I would very respectfully disagree with you - it always boils down to the #'s no matter what.

I dont expect to change your mind, but I dont see how we are supposed to believe-

1. that all the testing numbers somehow dont matter. All the data is somehow skewed to make corecell look bad and is really meaningless.

(first you accused me of posting bogus data now you say the data itself is meaningless)

2. The most successful names in performance boating all have it wrong and are building boats out of material you specifically say is flower planter material.

When you say things like that you insinuate everyone else is stupid and only you get it.



UD

Hell back in the day you could buy one for 400,000 until the owners wanted every luxury in the world in them.

Only the engine room had 1/4 5 ply plywood on the sides and than 1 layer of glass over the plywood and just one layer of glass over the frames and juniper planks on the inside hull bottom.under the engines.The plywoods primary function believe it or not was to prevent plank print through years down the road that would happen if you used just glass over the planks.
The rest of the boat inside was just bare frames and planking like you would see in any wood boat.We would spray some deadly primer and paint on it dont recall what it was.

What you see in the pics on the website of the boats being built rightside up is the laying of the keel and than they would insert a couple of frames and than using a fairing batten across thoses frames they would get the shape of the frame needed to fill the gap and build it.All the boats started with a basic few frames to get the overall shape and just were tweaked and eyed in from there.
Once you had your frames all up you would fair the angles of the frames with a planer and grinder to get them flush to recieve the planking.Than the fun part planking.One guy mixes another spreads the thickened epoxy between the planks and on the frames and 3 guys nail them in with like a #8 copper nail.5 guys could pank up a boat in 2 days. That is the fun part as you see alot of progress so quickly.
Than a day of fairing the planking with a 36 grit grinder. Fun stuff i tell you.
Next step was 2 layers of 1708 on the bottom followed by fairing compound so there was no fiberglass sanding between coats.
Nexy step the 1/4 inch ply hung vertically on the sides glued with thickened epoxy and screwed in with drywall screws.
Next step some 1708 over the plywood after you removed the drywall screws and sanded any residue off followed by fairing compound. No glass sanding in the shop if you can help it.
And than the really fun part 2 days of the whole crew sanding and fairing with 3 foot fairing boards.Paul was great though on sanding day he would have you sand for the morning and thanmake the crew luch on the grill and give us the rest of the day off with a whole days pay.Not much but i thought it was nice of him and it kept the crew enthused.
The Buddy Davis line was one of the only convential fiberglass mold built boats in the area.Huge facility for the area, I think Wanchese.
I would go back and do it again if i had the chance,Dirty work but pretty cool all in all.Wouldn't want to do it at a glassboat shop though to dirty and itchy.

Uncle D-100 is a Baltek product you should Know that! the scrim you like there was in fact what started that company ,IMHO one of Schoells guys Back in the old days when it came in blocks and you had to place every one of them anyway he got the idea to put a fine mesh in them to facilitate the process,
Now that said Buzzi spent time in our shop when he raced a Gray Ivecco Cat in Key West one Year and he would bond the Core then rip the scrim off it and that was the advice he gave me on the subject, I built a 55 footer out of it and the sheets bag in like anything else.

My point here it that the D-100 was the strongest representation of that material as the glass scrim does not add to the physicals of the laminate it detracts!

Regards

No I was only pointing OUT your Fallacy here and fixation to a set of numbers that are useless when applied to some material and trying to show the Hydormats place in the scheme of things!