Old school or "new school" and technology ?

[MatFromPoland]

I know that some UK (very good and fantastic reputation boats) still made use traditional technology like laminated plywood etc.

A lot of fantastic RIB boats are heavy, solid like rocks.

But some companies started to use infusion, molded structures.

RIBEYE, Hydrosport.

Even new models of Parker boats (not RIB) started this year are stepped hulls made use infusion technology. When I asked why - customer request to have better fuel economy and speed.

But I know that heavy and solid boat is still better for offshore.
Even @office888 when compared new ZODIAC 2017 and prev models stated that probably for offshore he would select "old" heavier model.

So is there a room for new less weight boats ? Deeper hull or any other features ? Or still offshore boat (RIB) have to be heavy ?

I'm beginner so want to know what more experience persons thinks.

[beamishken]

I guess only time will tell how good the new generation of lightweight boats are. While modern lightweight engineered solutions might result in the same strength as previous over engineering, the engineers don't always get it right
Think fourth rail bridge v old fourth road bridge!
I've repaired several racing rowing boats built ultra light with honeycomb cores and there a Pita to repair. The laminated shell is difficult to strengtgen without adding weight and there also prone to water ingress between the core
Wether ribs suffer the same in future remains to be seen.
Personally I'm in the old school easy to repair or modify camp but time will tell if modern techniques make for better longer lasting boats!

[MatFromPoland]

I'm thinking about 7m "new school".

What be better, 7,4m light deep V RIB (hoping to fit boat between waves crests)
Or "old school" 6m boat ? This is the question

I saw in Greece 10y old boats from both schools in the same good conditions but they had not so many hrs (like 200 - 300 hrs).

Let's forgot about school and material.

For example I can be in my towing limit with Hydrosport 737
And can't be in tow limit with Redbay 6,1
One of the factor is probably stronger and heavier Hypalon in Redbay ...

Now I don't know if go for bigger but not heavy (to be in my towing limit).
Unfortunately changed car to the same (Honda Odyssey) but newer with the same towing limit 1550 kg (even with towing package).

[Andre]

Originally Posted by MatFromPoland

I'm thinking about 7m "new school".

What be better, 7,4m light deep V RIB (hoping to fit boat between waves crests)
Or "old school" 6m boat ? This is the question

I saw in Greece 10y old boats from both schools in the same good conditions but they had not so many hrs (like 200 - 300 hrs).

Let's forgot about school and material.

For example I can be in my towing limit with Hydrosport 737
And can't be in tow limit with Redbay 6,1
One of the factor is probably stronger and heavier Hypalon in Redbay ...

Now I don't know if go for bigger but not heavy (to be in my towing limit).
Unfortunately changed car to the same (Honda Odyssey) but newer with the same towing limit 1550 kg (even with towing package).

Matt if you want a rib for towing and you have a weight limit then of course the new school but if the want a rib to cope with different sea conditions and not just calm and flat water then the old school is the way to go

[office888]

What I like in an offshore RIB:

• Shoebox type hull-deck joint
• Mechanically attached tube
• Anti-stuffing reinforcing plates in the bow
• Big spray deflecting chines
• Minimal planing pad
• Steep deadrise at the transom
• Spray deflecting chines

Bonus:

• Infusion process
• Vinylester resin
• Full-length stringer assembly

[Poly]

Originally Posted by MatFromPoland

... stepped hulls made use infusion technology. When I asked why - customer request to have better fuel economy and speed.

interesting I thought the trend towards resin infusion was driven by:

• need to use less resin "just in case" = saving money
• less resin = faster curing = higher throughput
• the process means less styrene fumes for the workforce to inhale

of course customers might be asking for lighter boats too, or they might be spinning the "it actually saves us money" into "our process adds value to you".

[office888]

Originally Posted by Poly

interesting I thought the trend towards resin infusion was driven by:

• need to use less resin "just in case" = saving money
• less resin = faster curing = higher throughput
• the process means less styrene fumes for the workforce to inhale

of course customers might be asking for lighter boats too, or they might be spinning the "it actually saves us money" into "our process adds value to you".

Resin is heavy and brittle. It doesn't add strength.

More glass adds strength.

[Poly]

Originally Posted by Andre

but if the want a rib to cope with different sea conditions and not just calm and flat water then the old school is the way to go

from a hull strength perspective or because a heavy boat is more "planted" in the water? if the later is a new school boat with ballast tanks the solution - heavy when you want it but efficient when it doesn't need to be?

[Poly]

Originally Posted by office888

Resin is heavy and brittle. It doesn't add strength.

More glass adds strength.

I'm aware of that - what's your point?

[office888]

Originally Posted by Poly

I'm aware of that - what's your point?

Two boats with the same layup schedule, the infused boat will be lighter because less resin will be utilized. It will also be a stronger boat because of the less likely chance of a stress riser developing in a puddle of unsupported resin.

The drive to use less resin is driven by that fact that too much resin is just as bad as not enough.

Infusion guarantees "ideal mix / ideal coverage".

[Poly]

Originally Posted by office888

The drive to use less resin is driven by that fact that too much resin is just as bad as not enough.

Its at least 20 yrs since my materials science lectures, but I am fairly sure the curves are not symmetrical. Although of course it will depend on the type of "strength" we are looking for. We agree though that you can use less resin to build a stronger boat that weighs less if you can control the infusion of the resin into the fibre. But is that driven by the customer wanting a lighter/faster boat or by the builder wanting to make at least as good a product with less cost?

[MatFromPoland]

I know nothing about making boats (my motto is I know that I know nothing)

One of my friends has small shipyard for small speedboats.
He told me that he want go for infusion to eliminate/reduce human errors.

To eliminate/reduce "pistols" and paint roller work. So I guess that he will look less at employee hands (now all the time).

I'm big fan of printing boats. Mentioned below was some prototype but they plan to have functional printed submarine boat in 2019.

https://www.youtube.com/watch?v=_GlxVjAHofk

Hope that orders from NAVY push this solution to commercial level.
People be able to project any complicated hull and print it ...

So my understanding about fusion that process is less sensitive on human factor, environmental (temp, press, humidity, ...). So maybe it was the reason - maybe as "side factor" hull is solid but lighter ??

[Andre]

Originally Posted by office888

Two boats with the same layup schedule, the infused boat will be lighter because less resin will be utilized. It will also be a stronger boat because of the less likely chance of a stress riser developing in a puddle of unsupported resin.

The drive to use less resin is driven by that fact that too much resin is just as bad as not enough.

Infusion guarantees "ideal mix / ideal coverage".

I can agree with this and we have the option of both methods as we have the infusion technology and skills but the choice is with the client as the infusion process is more expensive

[office888]

Originally Posted by Andre

I can agree with this and we have the option of both methods as we have the infusion technology and skills but the choice is with the client as the infusion process is more expensive

Do you guys use a molded stringer system, or is it hand laid?

From your gallery, it looks like your decks are molded.

[gtflash]

Agree with office and poly. Having ground up large proportions of a hand laid boat. Not only is excess resin a weakness but so too is not enough. No strength in dry glass.

If I was a boat builder I would be happier knowing it was built right and with perfect ratios. If it needs more weight, just add a choosable add an old school ballast tank.

[simonl]

What's the key advantage of increased weight? Is it just about reducing deceleration when landing, or are there other factors, like increasing inertia to prevent (yaw)/pitch/roll in in chop?

[Andre]

Originally Posted by office888

Do you guys use a molded stringer system, or is it hand laid?

From your gallery, it looks like your decks are molded.

we use both systems and this depends on the model. All decks are moulded with a non-slip finish

[GuyC]

Originally Posted by simonl

What's the key advantage of increased weight? Is it just about reducing deceleration when landing, or are there other factors, like increasing inertia to prevent (yaw)/pitch/roll in in chop?

In general the only reason you would increase the weight would be to increase the boats draught. For everything else you would try and move existing weight.

[MatFromPoland]

Just found yesterday Croatia boat builder.

Sorry this video is on the FB but you don't need to be log in to watch it:

https://www.facebook.com/Falkor22/vi...3766755151653/

Infuzion, vinyloester, sandwich, kevlar, carbon ... all new technologies.
Boat 6.5m weight 350 kg (not sure if with batteries and cushions)

I know it is not UK style (I do prefer jockey seats also) but building looks impressive.
And with Suzi 140 they report 0.6l per mile.

In 2018 I plan to be week or more in Croatia so really curious if they have any DEMO.
But usually in Croatia is calm so be hard to test it on waves.

This hull with wider console, jockey seats, wider rear bench be very interesting for me.



I'm still looking for bigger boat easy tow around EU (light weight GVW of the trailer 1300kg for example)

http://falkor.hr/en/project/

[jwalker]

Originally Posted by office888

Two boats with the same layup schedule, the infused boat will be lighter because less resin will be utilized. It will also be a stronger boat because of the less likely chance of a stress riser developing in a puddle of unsupported resin.

The drive to use less resin is driven by that fact that too much resin is just as bad as not enough.

Infusion guarantees "ideal mix / ideal coverage".

This is too simplistic a view imho, define stronger. Frequently, stronger refers to tensile strength, is this what you are referring to?

Hull structures are complex in their requirements since they have to withstand the vagaries of travelling through complex wave patterns. This, in turn, loads the hull in an ever changing stress pattern. The hull needs to withstand these forces without deformation so rigidity is important, rigidity is also important from other standpoints. At a practical level a rigid boat handles well; also, structurally, panel flexing is to be avoided because there will be high tensile stress and compressive stress at the flex area.

Resin rich laminates, while not stronger in tensile strength will be stiffer because they are thicker and the glass will be more diffusely distributed within the laminate.

Originally Posted by MatFromPoland

Infuzion, vinyloester, sandwich, kevlar, carbon ... all new technologies.

Mat, these are not new technologies, they have been around for many years but they have limitations too and it's not correct to presume they are modern substitutes for basic glass fibre materials. Of course they can be and are used to good effect in some structures but their working characteristics need to be properly understood.