DIAB Foam

[rwatson]

To all - sorry for this bit of thread hijacking, I just dont want to end up like the original post

Hi themanshed - All this info is very,very welcome - dont apologise for saying too much :-)

Originally Posted by themanshed

Hole in the foam is not keen in my book that is chance to de-laminate. The sheer force cannot be transfered between the skins. I drilled 1/8 inch holes 1 inch on center to raise the sheer in places. The holes were filled with bog. It is recommended to not have any voids in the foam. If you have a void it should be filled with a bog. They do make foam with small holes for the vacuum to suck resin though the foam to wetout both sides of a "panel" layup. The voids are filled with resin it does increases the weight. .

Ths is very interesting. In my mind, having places where the inner and outer skin joined seemed a good idea, (obviously only after the bend has been put in place.) I was thinking if is was a substantial join (say a 1/2" hole filled with resin) that it would be advantageous. I will need more advice on this. I might start another thread about it under fibreglass.

Originally Posted by themanshed

One layer of 200g E-glass unidirectional 90 degree may bend, perhaps you may want to try just one side first. Edge glue the sides of the foam with epoxy careful to not get any on the plane surface, if you do clean it up. The foam and glue sand at different rates, usually the foam will dish out.

yes, sorry, I didnt make myself clear obviously - on the flat layup table I only lay one outside skin of 200 gsm and CSM layer. When that cures, I bend the panel into the basket.
I plan to only glue one side of the foam sheet (yellow) to the thin layer of glass , (grey) (see crude illustration)

The rest of the layup is done once the bend is in.

Thanks for all the input

[Jimbo1490]

I like to think of a cored panel as a 'planar I beam'.

[apex1]

Originally Posted by rwatson

Thats good. I couldnt find anything after a quick look. I thought they only did plywood kits. Do you have a link ?

http://www.bateau.com/proddetail.php?prod=LB26 start there.

But I would leave the plastic cr@p where it belongs and use Kiri and Epoxy instead! When you calculate that thoroughly, with a 19mm wood core you come out at the same price than with foam and vinylester, but have by far the better result!
No matter what others say, pound per pound and cent per cent you do´nt beat wood (except for CF in some case). There is no dry rot or other issues when done right.

Regards
Richard

[themanshed]

No matter what others say, pound per pound and cent per cent you do´nt beat wood ...

I do not disagree with this but the reason for foam is to reduce the pound for pound and foam can make some sweet curves. You could steam wood until it becomes rice and never curve it like foam. If you are keen on wooden cores, there is nothing wrong with wooden cores, check out Kurt Hughes CM method it is what drew me to his designs. Using this method you basically construct your own continuous sheet of curved plywood then cut out the sides and stitch the sides of a hull together. I like the built in curve this method provides. The wood foam debate may go on forever or at least until all of the trees are gone. Each side has it merits and minus points.

Personally I like foam one reason you don't have stringers and in the tropics where a pinhole can start rot rather quickly I shy away from wood, even in my house. Foam may be considered new wave although it has been around for 20 some years. Foam also has built in buoyancy. After many years of poly resins I have converted to epoxy.

[apex1]

When you look at my gallery you may know why I´m saying what I said.

Richard

[themanshed]

Very nice woodworking! The boating world has many Facets a nicely fitted motor yacht should be wood; a sleek racing sailing boat should be foam. Now if you want to cut some weight out of her foam and fiberglass does polish up nicely.......

The same reason I do not live in a wooden house in Hurricane country.

[MarineSurvey]

An update for everyone: A few weeks ago, a manager, Benny (he called from his cell phone), at DIAB’s Asian offices called us to inform us that one of the bosses from Sweden was going to come to China to meet with us to resolve the mess that they created. It is fortunate for us that we did not believe them. It turns out that this was, indeed, another deceitful tactic from DIAB to try to get out of the agreement that they signed to a Chinese company by stalling us. It has seemed rather obvious to us for some time that DIAB believes that a Chinese company must be run by idiots who cannot see what DIAB is doing. We have spoken with other individuals and have heard the same thing about western suppliers: that the suppliers have an attitude toward them because they are Chinese. We refuse to simply lie down and take this kind of behaviour. We would greatly appreciate if anyone who has had any similar experiences would let us know.

[Landlubber]

"We refuse to simply lie down and take this kind of behaviour. We would greatly appreciate if anyone who has had any similar experiences would let us know."..........

can you enlighten us further.....I do not quite get what it is that the behavior is that you are so upset about, being Chinese or western suppliers.....

ta...

[Alik]

It is something new in marine survey business - 'marine surveyors' publish survey information in the Internet.

Well, what will be next step?

[apex1]

I guess that this one is as much a Marine Surveyor as I am the lesbian daughter of the Pope!

Richard

[themanshed]

I've had good luck from the DIAB foam. Application of the use of the foam is up to the builder.

I've had good saws they seem to still have a problem cutting straight.

[rwatson]

Originally Posted by Jimbo1490

I like to think of a cored panel as a 'planar I beam'.

That was a great analogy Jimbo.

I did start another thread to stop mucking this one up on this subject.

Joining skins through foam cores.

in case anyone wants to "pitch in"

OK - now back to the wicked DIAB people.

[Ruby Tuesday]

Personally,I can empathise with 'MarineSurvey', & would like to contact him to discuss our respective experiences.

I have just had an infusion done on my 42' powercat by the DIAB "experts" & it has turned out a complete disaster! I used DIAB foam & CNC cut kits, used "Polyworx", had my workers do the DIAB training course, & had the local DIAB team themselves do the glass lay-up & infusion.

The result is tens of thousands of dollars in repairs to fill & fair & paint the hull & deck. There is print-through of the fibreglass cloth on 100% of the hull & deck, & large "suck-ins" all along the chines, knuck;es, sheers, stems, windows, etc., in fact at every foam edge.

There's no problem with the foam - it's actually great to use & easy to work with. I've infused all my bulkheads, hull longitudinals, tanks & floors & never had a problem.

I was totally sold on the infusion process until all this happened. I still think it is the way to build boats, but obviously there are major obstacles to overcome first.

I'd like to hear first-hand of 'MarineSurvey's' problems.

Cheers

[Herman]

What was the problem with the infusion? From what I can tell from your story, the boat filled perfectly. So the Polyworx software has done it's job, the foam has done it's job, but choices in glass fabrics, gelcoat and barriercoat might have turned out wrong. Also the layup might have suffered a bit. (along foam edges).

How did your test panels look? I presume you made test panels on a sheet of glass to test all the materials?

[AndrewK]

Ruby Tuesday, so sorry to hear about your infusion result.
Are the DIAB people saying what went wrong? and will they fix the problems?
I think infusion process advantages outweigh the disadvantages and would like to see it used more widely.
Can you describe the infusion strategy used for your boat, are the defects due to air leaks or resin flow path lockouts, photos always help.
The more information you can provide can only help others avoid the same bad experience.

regards
Andrew