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nzjetboating.com Forums => Tech Library => Hulls => Topic started by: tyro on July 28, 2015, 11:55:00 AM

Title: fitting plastic can it have a detrimental effect on handling?
Post by: tyro on July 28, 2015, 11:55:00 AM
Can retrofitting plastic to a hull for which it wasn't originally intended affect the handling in a bad way? Also 8mm bottom vs 10mm bottom in a 12 foot hull, will the 10mm bottom make the hull significantly more bash proof or is 8mm ok?
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: mohawk on July 28, 2015, 13:59:56 PM
10 ,      8 is junk if you drive like karl.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: swifty on July 28, 2015, 16:13:31 PM
Can retrofitting plastic to a hull for which it wasn't originally intended affect the handling in a bad way? Also 8mm bottom vs 10mm bottom in a 12 foot hull, will the 10mm bottom make the hull significantly more bash proof or is 8mm ok?
Personally I wouldn't do it on a big hull, manufactures recommend not to do it. Seems to be ok on little hulls because they don't handle in the first place.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Karl on July 28, 2015, 17:51:18 PM
Personally I wouldn't do it on a big hull, manufactures recommend not to do it. Seems to be ok on little hulls because they don't handle in the first place.

Hey Swifty, why did my little 10ft kawasaki 1100 powered boat come second at the Northern districts giant slalon day. The only boat to beat me was a LS2 powered scott, the other 15 were all big boats!!!

Small boats can handle well if you design them properly.

Anyway we are a bit off topic, my choice is 10mm alloy with 10mm plastic down the delta section, around 400-600mm wide depending on the boat size.  To retro-fit you can use planning strakes to secure the edges and need to modify the grill opening to secure the plastic completely.

Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Henry on July 28, 2015, 18:33:34 PM
I have had plastic (10mm thick 600mm wide & on top of alloy) & no plastic on identical hulls. Only difference i have noticed is a slight loss of top speed.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: tyro on July 28, 2015, 18:49:25 PM
so I understand that the plastic makes the hull alot easier to push, and it resists scratching but what measure of protection does it give against denting? for instance is 8mm + 10mm plastic more resistant to denting than say 10mm with antifriction slide paint?
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: garth44 on July 28, 2015, 19:03:57 PM
Personally I wouldn't do it on a big hull, manufactures recommend not to do it. Seems to be ok on little hulls because they don't handle in the first place.


Never in my life did I wish they had a dislike button more than right now.......... Been in some small boats and dam can they handle.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Karl on July 28, 2015, 19:24:01 PM
Plastic adds very little to impact strength, you just end up with dents underneath in the alloy. Real easy to push though!!!
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: mohawk on July 28, 2015, 20:07:18 PM
I thought about 8 and plastic , but the weight of the plastic and bolts or a 10mm bottom was a no brainer.
I don't live near a shingle river though , but the slide lasts well on the little boat and it only takes a second too touch up .
How much time do you intend spending on the bottom of the river anyway ??  Most of the people I know get over that crap pretty early . You can smack a rock in the middle of nowhere  any time and that's when you will wish youd gone thicker.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Jeff B on July 28, 2015, 21:12:23 PM
so I understand that the plastic makes the hull alot easier to push, and it resists scratching but what measure of protection does it give against denting? for instance is 8mm + 10mm plastic more resistant to denting than say 10mm with antifriction slide paint?
My educated guess would say that you are pretty close comparing 8mm ali with 10mm plastic has similar IMPACT resistance to 10mm ali.
Plastic is floppy but springs back to its original shape(memory)
My suggestion would be, if you boat shingle shallow rivers and don't like pushing, use thinner ali plus plastic.
If you boat bigger, deeper, bouldery nasty rivers, use thicker ali.
If you want both, use thick ali plus plastic. 2c
I am biased towards thicker ali as it gives you something stronger for your bolts to go through.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Paul on July 28, 2015, 21:33:26 PM
If you want both, use thick ali plus plastic. 2c

What spec is the bottom of 'Stink Nuts'?
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Karl on July 28, 2015, 21:43:19 PM
Probably 12mm as he is still learning!!
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Richard Anderson on July 28, 2015, 22:36:15 PM
Hi My last Rivercraft was 12mm alloy + 10mm plastic and new one 12mm alloy +10mm plastic on 4.2m boat. great handling.No problems at all.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: swifty on July 29, 2015, 01:28:50 AM
Hi My last Rivercraft was 12mm alloy + 10mm plastic and new one 12mm alloy +10mm plastic on 4.2m boat. great handling.No problems at all.
recessed into the hull when built is the correct way to do it as yours were. p.s that's a fancy set of exhaust's you have on your new motor.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Jeff B on July 29, 2015, 10:28:56 AM
What spec is the bottom of 'Stink Nuts'?
Stink nuts has 12mm ali and 11mm plastic.
Yep I'm still learning, we all are.....except a few people that already know everything l-l
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: swifty on July 29, 2015, 15:25:41 PM
Hey Swifty, why did my little 10ft kawasaki 1100 powered boat come second at the Northern districts giant slalon day. The only boat to beat me was a LS2 powered scott, the other 15 were all big boats!!!
The only explanation I can think of is superior driver skill.
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: mohawk on July 29, 2015, 21:04:12 PM
Karls ability behind the wheel has left many of us steering in stund disbelief on occasion  ;D ;D
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Karl on July 30, 2015, 08:20:15 AM
The only explanation I can think of is superior driver skill.
As Mowhawk has pointed out an unlikely explanation!!
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: mohawk on July 30, 2015, 10:09:40 AM
Great , now jeffs guna think its his hull and well never shut him up  hhh

maby it was 2 stroke power karl  b>
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Warwick Marflitt on December 28, 2020, 10:46:05 AM
So 5 years and a Pandemic later! Have any further conclusions been made opinions arrived to. As to Plastic/alloy thickness and its proven real life use advantages/issues???   
Title: Re: fitting plastic can it have a detrimental effect on handling?
Post by: Jocsax on December 28, 2020, 12:11:50 PM
Stinknuts plastic is looking pretty 2nd hand but everyone who pushes it vs pushing a non plastic boat wants plastic pretty quick (canterbury shingle).