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shifter
11-30-2008, 12:13 AM
We are looking at making some major mods to an existing kevlar hull. I want to cut it length wise and rebond the hull.

Is this possible?

Will the structure be ok since the original bond layup (grain/weave) has been cut?

Thanks in advance,
pat W

Offshore Ginger
11-30-2008, 12:37 AM
We are looking at making some major mods to an existing kevlar hull. I want to cut it length wise and rebond the hull.

Is this possible?

Will the structure be ok since the original bond layup (grain/weave) has been cut?

Thanks in advance,
pat W first off what type of hull and yes anything is possible . just curious are you talking rebondining the deck to the hull ?

glassdave
11-30-2008, 12:38 AM
sure its possible but it is a big roll of the dice when you compromise the continuity of the laminate. Being Kevlar makes it a tough one to do, also keep in mind that you will add a fair amount of weight trying to re gain enough structure. What boat are you talking about? Are you trying to narrow a boat up?

Offshore Ginger
11-30-2008, 12:59 AM
sure its possible but it is a big roll of the dice when you compromise the continuity of the laminate. Being Kevlar makes it a tough one to do, also keep in mind that you will add a fair amount of weight trying to re gain enough structure. What boat are you talking about? Are you trying to narrow a boat up?
Dave , just curious why do you feel that being kevlar makes it a tough one to do and just because its kevlar why would you have to compromise the laminate ? I D T S........................:rofl::rofl::rofl:

MOBILEMERCMAN
11-30-2008, 01:03 AM
I've cut out stringers to relocate in a kevlar boat. Like Dave said it is tough. Hard to cut. Then when it is time to grind it is tough again. Furr balls every where. I hope your glass man loves you. Doing that job will likely put a dent in your relationship. Good luck.

Offshore Ginger
11-30-2008, 01:12 AM
I've cut out stringers to relocate in a kevlar boat. Like Dave said it is tough. Hard to cut. Then when it is time to grind it is tough again. Furr balls every where. I hope your glass man loves you. Doing that job will likely put a dent in your relationship. Good luck. I hate to say this but i would rather grind on kevlar all day long opposed to #1708 , carbon fiber , S or E glass and yes it is a little harder to cut , but that goes along with the job .

MOBILEMERCMAN
11-30-2008, 01:19 AM
I hate to say this but i would rather grind on kevlar all day long opposed to #1708 , carbon fiber , S or E glass and yes it is a little harder to cut , but that goes along with the job .

That's good cause it takes all day to grind something that should only take hours. Plus it seems to eat up the tools too.

Sorry Dave and Pat didn't mean to side track.

glassdave
11-30-2008, 01:37 AM
Dave , just curious why do you feel that being kevlar makes it a tough one to do and just because its kevlar why would you have to compromise the laminate ? I D T S........................:rofl::rofl::rofl:

Art the purpose of this thread is to determine the viability of cutting a Kevlar boat in half and bonding it back together not weather it can be done. Can it? well sure. should it? well thats another thing all together. My personal thought is i am assuming its a race boat and will be run to the highest levels. Scarf ratio for a laminate in that area of the boat would leave you a pretty big swath on the inside and the outside of the boat to deal with. Could be a very huge mess and if it developed problems down the road would render the boat worthless. Just not sure if its the best roll of the dice. At this point we'll need a little more info from Pat and see if we can help him pick a direction.

glassdave
11-30-2008, 01:42 AM
Sorry Dave and Pat didn't mean to side track.

Dont mention it Jim, we're all here to learn. All info is welcome and relevant.

Offshore Ginger
11-30-2008, 11:28 AM
So is the hull a cat or ....................:)

AGITATOR
11-30-2008, 11:58 AM
hey ginger do you remember what material my skater is made of just curious

Offshore Ginger
11-30-2008, 03:04 PM
hey ginger do you remember what material my skater is made of just curious Its been a long time and i would say that your boat was built using AME # 4000 and most of the fabric being # 1708 . Funny thing my partner and i at the shop who still works at Skater after 18 years were just talking about the transition of building boats from AME to epoxy at Skater and all the learning curves we went thru while makeing the change.:seeya:

Offshore Ginger
11-30-2008, 03:07 PM
God i love seeing Skater avatars lined up back to back .:)

shifter
11-30-2008, 06:45 PM
It is a vee. I do not plan on cutting the boat completely just through the running surface.

We were looking at putting it into a cnc router and cutting it then bonding the changes back in to the hull.

For a test I thought it would be better to do this than cnc-ing a complete hull from scratch.

In the back of my head I keep thinking the patch/bond is going to fail.

If we take this old hull and extensively modify, test it and splash the plug, is this still considered splashing?

I just do not want to get burried into this project and not be able to sell it when we are done because it is considered a copy.

Thanks for the help so far,

pat W

Offshore Ginger
11-30-2008, 07:18 PM
I have tried to write something three times and have been cut off at the knees .............................................. ART

Offshore Ginger
11-30-2008, 07:34 PM
Shifter - no hull Legally , is considered splashing , unless you make a 10 % change . Shifter consider this as words of past experience and just curious who might be doing your CNC and where is your location ?.:)

AGITATOR
11-30-2008, 08:42 PM
is ame#4000 any good and what type of resin would you repair that with epoxy?????

Offshore Ginger
11-30-2008, 10:27 PM
is ame#4000 any good and what type of resin would you repair that with epoxy????? Hey guy , i mostly use the same resin for big repairs , that Skater uses to build there boats with today and on smaller repairs , dependinng on the size of the repair i would go with West system 105 epoxy resin and 206 slow hardner orrrrrrrrrrr even slower 209 which is extra slow which will give you a lot more pot life and work time . AGITATOR , Douglas Marine uses these products on a every day basis , just my 2 cents .......................... Art:seeya:

glassdave
11-30-2008, 10:31 PM
Artie when did Skater stop using AME4000 and go all epoxy? Or is that what the AME was? cant remember been a while

SHARKEY-IMAGES
11-30-2008, 10:40 PM
Shifter - no hull Legally , is considered splashing , unless you make a 10 % change . Shifter consider this as words of past experience and just curious who might be doing your CNC and where is your location ?.:)

Not any more ......


http://www.ibinews.com/ibinews/newsdesk/20080917155321ibinews.html


Bush signs bill that will protect against "hull splashing"

By IBI Magazine

US President George W Bush yesterday signed into law the Vessel Hull Design Protection Act Amendments (VHDPA) of 2008. The VHDPA Amendments correct a technical issue found in the original VHDPA of 1998. According to a statement from NMMA, the amendments now give boat manufacturers increased protection from intellectual property violations that occur through "hull splashing" or duplicating hulls.

"The VHDPA Amendments recognise the great amount of time and money that goes into developing state-of-the-art vessels," said Thom Dammrich, NMMA president, in the statement. "This new and improved VHDPA is a huge step forward in protecting the intellectual property of boat manufacturers."

Dammrich said that NMMA has been working with the US Congress for six years to clarify the Vessel Hull Design Protection Act of 1998. He said that VHDPA Amendments correct technical issues in the original law which, under certain legal interpretations, allowed boatbuilders to splash other builders' original hulls. "They provide boat manufacturers the full protection originally intended in the 1998 VHDPA," said Dammrich.



(17 October 2008)

Offshore Ginger
11-30-2008, 10:53 PM
Thanks Sharky , i was not aware of that and i guess i am never to old to learn something new and with that in mind ...................... Shifter you have an open hand .:rofl::rofl:

Offshore Ginger
11-30-2008, 11:15 PM
Artie when did Skater stop using AME4000 and go all epoxy? Or is that what the AME was? cant remember been a while Dave i will be talking with Pete this week on a few gas tank repair's that i will be starting and i will ask him when he thought the transition from conventional resin boats to Shell epoxy boat's began ,and no that is not what the AME was . Artie

glassdave
11-30-2008, 11:31 PM
Yea i thought the AME was either a high quality poly or vinylester, wasnt sure. Good stuff at any rate.

SHARKEY-IMAGES
11-30-2008, 11:55 PM
Vinylester

Offshore Ginger
12-01-2008, 12:16 AM
Yea i thought the AME was either a high quality poly or vinylester, wasnt sure. Good stuff at any rate. Dave very good stuff # 4000 #5000 and # (6000) which is mostly used when doing fusion because it is a very thin resin . Take care my friend :seeya:

Offshore Ginger
12-01-2008, 12:20 AM
Vinylester You Dawgggggggggggggggg your on it :rofl::rofl::rofl: now go back to takeing pictures . :rofl::rofl::rofl::leaving:

glassdave
12-01-2008, 12:32 AM
Vinylester

thought it was something like that, thanks.

Hey the pic in you avitar, got a bigger shot of that? Looks like the Point this year. Danny was runnin the heck outta that boat.:D

Steve 1
12-01-2008, 12:38 AM
Nice thread guys I will stop in tomorrow .

SHARKEY-IMAGES
12-01-2008, 12:58 AM
You Dawgggggggggggggggg your on it now go back to takeing pictures .
There were a few things I did before taking photographs .... ;)

http://sharkeyimages.zenfolio.com/p570079324/slideshow




.

http://sharkeyimages.zenfolio.com/img/v4/p871299914.gif

http://sharkeyimages.zenfolio.com/img/v6/p543378400.jpg

http://sharkeyimages.zenfolio.com/img/v6/p645453490.gif

http://sharkeyimages.zenfolio.com/img/v4/p1021295076.gif

shifter
12-01-2008, 01:04 AM
When we are done with the mods it will not be anywhere near the original part and I mean nothing similar. We just need it as a chassis to hold the shape of the new design. I just do not want to spend a fortune on glass to test a prototype.

I can see splashing a cat and getting a cat mold but that is not what we are doing.

There are several gantry mills around us, we are in So Cal the home of hot rodding.

Can you cut it with a skill saw blade? Can we use vinylester or do we have to know the original lay up?

pat W

SHARKEY-IMAGES
12-01-2008, 01:36 AM
If I am not mistaken, vinylester can be used over vinylester, epoxy can be used over vinylester, but vinylester cannot be used over epoxy.

Audiofn
12-01-2008, 09:31 AM
You are correct Sharkey

AGITATOR
12-01-2008, 09:58 AM
thanks guys

Steve 1
12-01-2008, 10:06 AM
Dave AME is Ashland Modified Epoxy is A vinylester They play with the words here this is not an Epoxy by any streach … they react a epoxy base with an Acid (adipic for one) to place some Vinyl groups on the Epoxy molecule then with styrene as the reactive component we simply sweeten to taste with MEKP and use it. Back it the early days they would leave buckets of the old AME 4000 as samples (I was using the Dow 470-36 in those days) I tooled the PP 38 Molds with the AME 5000 and now they have a nice 6000 infusion resin.

Steve 1
12-01-2008, 07:24 PM
Shifter any core in that hull? and Yes you can cut it with a skill saw just screw down a guide and take "small bites" cheap carbide blade will go right through. Do it all the time on repair jobs.

Offshore Ginger
12-01-2008, 08:35 PM
SHIFTER ( Pat ) is the original layup epoxy or ........................ Pat just a suggestion there are some epoxies out there that will give you more work time and the ability to lay up around 6 to 7 layers of glass with no problem . Pat Skater uses an epoxy that is just awesome and made by shell and the work time is unreal . I have just receved 5 gallons of Proset made by West system that MTI uses and the pot life is 90 min at 70 % to try out . i guess what i am trying to say issssssssssssssssss the less time spent grinding to achive structural intergrity is a god send .:sifone:

shifter
12-02-2008, 01:39 AM
Is there a way to tell if it is epoxy or not? There is approx 2 inches of core, I have not taken a measurment it is just an estimate. lots of extra stringers.

I was looking at glassing in a sub structure to support the hull during the mods with the future shape already there. The deck is already gone in the dumpster. I have a feeling if I do not support the hull it will warp when we cut it. We are new to this. This is why I am asking.

I recently made a naca on the cnc as a guide for a rotozip, plus .625. It worked really well but it was a simple 1 inch thick, glass on both sides, penske board.

I can just wood screw the guides to the bottom right?

Thanks again for the input

pat W

Steve, we had to race against your boats in Dubai, I was with M13,M7,M1 in 95/96 that was fun, Abu Dahbi was tough, seemed like 30 boats. Were you there with Doug? Do you still make wooden hulls?

glassdave
12-02-2008, 01:51 AM
Is there a way to tell if it is epoxy or not? There is approx 2 inches of core, I have not taken a measurment it is just an estimate. lots of extra stringers.

I was looking at glassing in a sub structure to support the hull during the mods with the future shape already there. The deck is already gone in the dumpster. I have a feeling if I do not support the hull it will warp when we cut it. We are new to this. This is why I am asking.

I recently made a naca on the cnc as a guide for a rotozip, plus .625. It worked really well but it was a simple 1 inch thick, glass on both sides, penske board.

I can just wood screw the guides to the bottom right?

Thankd again for the input

pat W

Steve, we had to race against your boats in Dubai, I was with M13,M7,M1 in 95/96 that was fun, Abu Dahbi was tough, seemed like 30 boats. Were you there with Doug? Do you still make wooden hulls?


one quick way is if its gel coated it is likely poly. If its a thin coat of paint and right into laminate it is likely epoxy.

Definetly support the hull squarley and securley before you start taking out major structure.

Yes you can screw forms and guides on with any type of dry wall screw or sheet metal screw.

What kind of hull is it? pics? With the talent we have here lately i think we can come up with answers to anything you run across.

shifter
12-02-2008, 02:20 AM
It was an old raceboat, not to sure what, but it is a doner so I cannot complain. Cougar 38 maybe. It has those funny turned up strakes in the bow. It is all white and no deck. I took the measurements so I could make a base drawing and propose changes. I didin't get any photos, camera was dead. It is out of state so I cannot check what it is real easy. 20deg dead rise no steps and a notched transom.

That is all I know so far,

pat W

Offshore Ginger
12-02-2008, 11:00 AM
Pat what year is the boat ? Pat a friend of mine has a 38 and another friend has a 46 and both boat's are made out of conventional resins and i think that your boat is not an epoxy boat but .........you never know and could we see some pics :)

Steve 1
12-02-2008, 12:00 PM
Is there a way to tell if it is epoxy or not? There is approx 2 inches of core, I have not taken a measurment it is just an estimate. lots of extra stringers.

I was looking at glassing in a sub structure to support the hull during the mods with the future shape already there. The deck is already gone in the dumpster. I have a feeling if I do not support the hull it will warp when we cut it. We are new to this. This is why I am asking.

I recently made a naca on the cnc as a guide for a rotozip, plus .625. It worked really well but it was a simple 1 inch thick, glass on both sides, penske board.

I can just wood screw the guides to the bottom right?

Thanks again for the input

pat W

Steve, we had to race against your boats in Dubai, I was with M13,M7,M1 in 95/96 that was fun, Abu Dahbi was tough, seemed like 30 boats. Were you there with Doug? Do you still make wooden hulls?


The Kuwaitis hired me; the prototypes I do are all in wood ..the running One offs are Corecell or Airex I built about 24 of them so far Cats and Vees. A friend of mine got killed in Abu Dhabi right in front of me in a RIB I stopped racing and built boats that killed bad guys (patrol and gun boats) we had about 30 of them in the Gulf then got the bug again!

Doug was a great guy and one of a kind.

shifter
12-02-2008, 12:40 PM
Ginger,

It is an 1985 or 1986. I will get some photos when I make it back to AZ. Was this boat done with a chopper gun? It did not look very good on the inside, the stringers were a little chunky.

Steve,

I was wondering what it would cost not to go this route but to make a prototype out of wood? 44x9x9.

What year were you racing over there?
pat W

Steve 1
12-02-2008, 01:06 PM
Ginger,

It is an 1985 or 1986. I will get some photos when I make it back to AZ. Was this boat done with a chopper gun? It did not look very good on the inside, the stringers were a little chunky.

Steve,

I was wondering what it would cost not to go this route but to make a prototype out of wood? 44x9x9.

What year were you racing over there?
pat W

Running Prototype?

My boats ran 92-95 then we had a death and ran only national races in Kuwait after that I came home in 2000.

shifter
12-02-2008, 01:43 PM
I think that Victory did not run that race something about the not letting the divers up in the chopper smooth on the inside and rough on the outside..... I was there in 95 with M-13.

The boat would want to be a running prototype.

pat W

Offshore Ginger
12-02-2008, 01:54 PM
Pat there is chop involved in there layup and what i saw was mat, but they very well could have used a chopper gun in some part of the build . All in all the old Cougar's were built like a brick $hit house . :seeya:

Steve 1
12-02-2008, 04:02 PM
I think that Victory did not run that race something about the not letting the divers up in the chopper smooth on the inside and rough on the outside..... I was there in 95 with M-13.

The boat would want to be a running prototype.

pat W


That’s right there was a Weather delay in the race we ran an "S" Boat Made the steps that day even with the driver going out to the sea buoy. The Italians wanted to buy my boat and that made me feel good and the homicidal thing went away. I was sitting in the turn right next to Doug as you come out of the Cornish run. Watching the “M” class run.

shifter
12-03-2008, 01:46 AM
We were running against M-1 that race. We tried a major change compared to the sister boat that race. We changed the overall ratio to compensate for the change from v-8 to v 6's. I was working with Serralles on the 3 speeds for Saeed. Kalfans boat had 2-speeds and 500lbs less. They were running 108 inside and 103 outside and we were running 108 all the way around. We were also running the prototype dry-sump #4 drives that race. I have pics of all that somewhere....


Back to today.... What direction would you take? Clean sheet of paper or hotrod an existing hull.

pat W

shifter
12-03-2008, 04:16 AM
found a pic and saved it for Ginger, as you can see.....daunting.

pat W

Offshore Ginger
12-03-2008, 11:15 AM
found a pic and saved it for Ginger, as you can see.....daunting.

pat W Pat l@@ks like a Cougar to me , notiched transom , typical Cougar red bilge and did she come with saddle tanks and if so are you going to reuse them ? Pat very interesting progect .

Steve 1
12-03-2008, 11:58 AM
We were running against M-1 that race. We tried a major change compared to the sister boat that race. We changed the overall ratio to compensate for the change from v-8 to v 6's. I was working with Serralles on the 3 speeds for Saeed. Kalfans boat had 2-speeds and 500lbs less. They were running 108 inside and 103 outside and we were running 108 all the way around. We were also running the prototype dry-sump #4 drives that race. I have pics of all that somewhere....


Back to today.... What direction would you take? Clean sheet of paper or hotrod an existing hull.

pat W

We had 4 boats there that day a couple RIBs and Two Cats The usual games with the scrutinizers I got to keep the canards but the cowlings had to go .we lost I RIB in a rollover (canopy failed) I was going to get Doug to do my motors for the next race which was the next step.

Myself I would just build a new hull it goes quick with what we have nowadays.

shifter
12-03-2008, 01:06 PM
They could not get the tanks out so they cut them out in pieces. The plan is to move the tank under the cockpit. I am still wondering what is under the tanks. Looks like 1/4 ply and hollow/5 ft long.... curtis secret stash.....

I guess if we make all these changes and do not splash it then we are ok. It is more of a proof of concept. What do you guys think about penske board?

Steve,

I would still like to know what kind of money is needed to make a mold the right way. I do not really want to go through all the bother to mod the old hull and the strip it to make a plug out of it.

All of a Quiver had fairings on the deck, were your cowlings the ones that were pointy?

pat W

Steve 1
12-03-2008, 01:33 PM
They could not get the tanks out so they cut them out in pieces. The plan is to move the tank under the cockpit. I am still wondering what is under the tanks. Looks like 1/4 ply and hollow/5 ft long.... curtis secret stash.....

I guess if we make all these changes and do not splash it then we are ok. It is more of a proof of concept. What do you guys think about penske board?

Steve,

I would still like to know what kind of money is needed to make a mold the right way. I do not really want to go through all the bother to mod the old hull and the strip it to make a plug out of it.

All of a Quiver had fairings on the deck, were your cowlings the ones that were pointy?

pat W

Give me a block size of the project LxWxH so I can work out material pricing without getting into your design specifics.

My cowlings were pointed as I was also aside from airflow concerned about the water inpact on them which turned out to be a non issue.

SHARKEY-IMAGES
12-03-2008, 05:28 PM
My cowlings were pointed as I was also aside from airflow concerned about the water inpact on them which turned out to be a non issue.

Something like this ? :D

http://sharkeyimages.zenfolio.com/img/v4/p328953389.jpg

shifter
12-03-2008, 05:52 PM
44 long X 9 foot wide X 5 tall. Maybe 12 wide....

Those are the ones. Shame on you for thinking outside the box.....

pat W

Steve 1
12-03-2008, 05:59 PM
44 long X 9 foot wide X 5 tall. Maybe 12 wide....

Those are the ones. Shame on you for thinking outside the box.....

pat W

I will put something togeather for you!

Steve 1
12-03-2008, 06:21 PM
When they weighed me out I was warned if the boat was 1Kg under they were going to ban me for a year. First off the scale tolerance was more than that so it got my attention.
Second everyone stopped what they were doing and gathered around when they weighed my boat and Plus the unknown distance that the Driver let’s say error to be kind took in extra fuel and finally my calculations based on a simple scale made from a steering ram and a gauge back at the shop and working alone.

I had a ballast system I could adjust to the gram if needed and I had enough time for second thoughts on shaving things that close, like this may hurt in front of the World.

Long and short of it +18 KGs

Offshore Ginger
12-03-2008, 07:21 PM
Shiffter , just curious do you have a drawing of what you might be heading towards as far as a deck ? Pat i have a lot of expierence in this , from adding more freeboard , custom deck's, canopy boats from race to pleasure and just the opposite and if i can be of any assistance as far as ideas , i would be more then happy to help ............ artie - AKA / OFFSHORE GINGER / G.G.

shifter
12-04-2008, 12:50 AM
Arti,

I see that you are homeless can you come to cali or would you want the boat to sleep in?????? :)

We are not glass people so I just need to get some quotes together and I will put it on a plate to the owner. I just reworked another hull and got screwed by the locals so that is why we are looking outside cali. I do not like talking out of my ass so I do my homework. To me this all seemed possible and so far it is.

You guys have been a great help so far.

pat W

Steve 1
12-05-2008, 04:35 PM
Arti,

I see that you are homeless can you come to cali or would you want the boat to sleep in?????? :)

We are not glass people so I just need to get some quotes together and I will put it on a plate to the owner. I just reworked another hull and got screwed by the locals so that is why we are looking outside cali. I do not like talking out of my ass so I do my homework. To me this all seemed possible and so far it is.

You guys have been a great help so far.

pat W

Check Your PM

Offshore Ginger
10-07-2009, 01:15 PM
SHIFTER , i will be sending you a PM.

MikeyFIN
10-08-2009, 06:16 AM
Arti,

I see that you are homeless can you come to cali or would you want the boat to sleep in?????? :)

We are not glass people so I just need to get some quotes together and I will put it on a plate to the owner. I just reworked another hull and got screwed by the locals so that is why we are looking outside cali. I do not like talking out of my ass so I do my homework. To me this all seemed possible and so far it is.

You guys have been a great help so far.

pat W

I would Recommend Fiberglass Services from Sarasota.

Wahoo 214
10-13-2009, 12:44 PM
There is a good thread on the Sunsation site showing how they cut and strechted their 32 into a 38. Might give some ideas on how they cut it and supported the hull while they pieced it back together.

Steve 1
10-13-2009, 04:03 PM
I Always use a pair of I Beams for rails to support my work.