Need some clarity on 'glassin new stringers/deck

[dccordell]

Ok guys, finally have the money saved to get started on replacing my rotten stringers and deck on my old deck boat I acquired at the beginning of summer. I already have it all cut out, motor out, everything...

I want to go ahead and order the stuff from USComposites so it will be there waiting on me when I get home from Alabama in a week or so. I just wanted to check that I'm ordering the right stuff at the correct quantities.

From what I've read, the best stringer replacement material is 3/4" exterior plywood, right? I'm lookin at Lowes, is this what I need? It seems none of them say plainly "3/4" exterior". It is only slightly thinner than 3/4" and rated for exterior.

How about using the same ply, just thinner, for the deck as well?

So many threads on here suggest using different fiberglass materials, but as far as I can tell it would be ok to cover the stringers with the 1708 biaxial, right? One layer or two?

On the deck, would 1.5oz. CSM be ok? I plan to have plenty of support under the deck, so I expect the plywood to be fairly solid. Is the fiberglassing here mostly just for water-proofing?

I think that's enough for this post.. lots of questions!! I just want to make sure I do this the correct way the first time. Don't want to have any issues on the water...

PS - I'm lookin all these materials up on USComposites... is this the best place to buy online as far as prices go? Darn stuff sure isn't cheap (haha!)

 

[ezmobee]

Re: Need some clarity on 'glassin new stringers/deck

That plywood should work well. Others may suggest marine ply. In my opinion, marine ply is a superior product, however it costs 3x as much and that's too high for me. I'm a tin boat guy so I can't comment on your layup schedule. A 3/4" deck will be plenty solid so yes your fiberglassing of that is for waterproofing. US Composites has been awesome for all our members that have used them.

 

[Woodonglass]

Re: Need some clarity on 'glassin new stringers/deck

Welcome to iBoats! You might want to check with your local Lowe's and see if they can order MDO plywood. It is a far superior product than Ext. Grade in that it is FLAT and Stays that way. Has mor Plys and less voids in the plys. It will cost a bit more but Less than Marine grade. It is rated for marine use and does use waterproof glue and better quality wood for it's plys. Your material list is SPOT ON. You did not give the dimensions of your boat but I would say it she is 18-20 ft you will need at least 5 - 10 gallons of resin/epoxy whichever you decide to use. (I would go with the resin) I would also recommend the dispenser pumps, a good matt roller, Gloves, respirator, tyvek suit, goggles etc. Don't forget to have plenty of Acetone on hand for clean-up.

Good Luck and pics are always welcome and helpful!!!!

I'm just sayin...

 

[j_k_bisson]

Re: Need some clarity on 'glassin new stringers/deck

If you are doing stringers and floor you will need at least 7-10 gallons of resin. This is due to the 1708 biax, it sucks it in like a black hole! It sure does drinks it up. I would use 2 layers of 1708 on the stringers. Possibly one layer on my floor. The 1.5oz CSM on the floor is a little light. Try to go with something thicker if not the 1708. The reason for this is you might wear that thin stuff through. Also if you should drop something on it, it might dent and exposed the wood to water. Just some thoughts.

I used Mertons for my epoxy source due to their products do not require me to wear a mask. Non toxic. Made the project way more easier! They where very competive in their prices to. Just another possible source.

I used the 3/4" plywood from Home depot. I had no issues. I do not see any issues with what you are suggesting.

Check out my project is you want to see how it came out. Link in signature.

 

[erikgreen]

Re: Need some clarity on 'glassin new stringers/deck

MDO looks interesting as a product. Have you done a boil test with it?

For those not familiar with it, it's basically a good quality plywood with exterior glue that has surface veneers of MDF, except it's a version of MDF made with phenolic glue that's waterproof.

The thing I'd be worried about is the shear strength of the surface veneers... IE if you glue to it with epoxy, will the veneer separate before the epoxy does? If so, is it much weaker/the same/stronger than a regular wood veneer?

Erik

 

[Yacht Dr.]

Re: Need some clarity on 'glassin new stringers/deck

Hello dccordell..

First off.. safty.. you should allready have a resporator, goggles, ear muffs, full paint/grindind suit and some shaving cream ( the shaving cream works two fold..one for you scruff so the respo works good and two put it on your body when showering will work out the fiberglass ).

Secondly..if your allready trying to get the money to finish..then the medium is more likely your bet.

Marine grade is best of best..and used for transoms Alot because its actually 3/4" .. void free .. has excellent glassing ( air void free lams ) etc..

Ex ply is commonly used for repairs for decks and stringers as long as its used with Proper prep before you try to glass over it ( resin coatings ). Some might find that there EX was not properly prepped and Air intrution occures..therefore creating more expence in the long run for a re-due then just shelling out 80 bucks for a sheet of Marine. You Can make your own marine style grade with resin alone before glassing.


As far as how many layers of glass for stringers ? Depending on the size of the boat.. However I would suggest you use 1.5 oz mat then 3 layers of 1708 ( 17 oz ). Its the First Bond you make that is Most Important.. you can lay on 14 layers of glass..but if your first one didnt bond..the other 13 will not do anything.

I will be the first one to say that I do over-do things..sometimes in extream.. but I will for a Fact be able to tell you that the 2-3 hundred extra in resin/glass will rest ease my mind .

GL and good resto ..

YD.

 

[dude11]

Re: Need some clarity on 'glassin new stringers/deck

Hi,I got my "stuff" at fiberglasssite.com---I found their products to be excellent,priced right ,great service,super fast shipping.Ck'em out!

 

[fish_on_the_deck]

Re: Need some clarity on 'glassin new stringers/deck

The 1.5oz CSM on the floor is a little light. Try to go with something thicker if not the 1708...

I agree! I'd do the 1708 on the deck, but at least a coupel layers of 6oz... think about dropping a sharp anchor on it... that would push right through one thin layer of cloth and expose your wood to rot!

Also... I use uscomposites... great prices by comparison... havent checked fiberglassite.

 

[drewpster]

Re: Need some clarity on 'glassin new stringers/deck

I used 15 gallons of resin to do transom, stringers, deck and seat box reassembly. I had to buy one additional gallon for incidentals and I have most of it left.

I used 1.5 oz. CSM and 18oz. woven roving to do everything. I hear 1708 is great stuff and when I do my big boat i am going to give it a try.

On my stringers- I bedded with PL premium glue, filleted all the corners and rounded all the tops. I used two layers of CSM, a layer of roving, then a layer of CSM to tab the sides. I then capped the stringers with a layer of CSM followed by roving. I then covered everything with a final layer of CSM, roving and finally CSM. This gave me the thickness I needed to meet the bottom of the deck elevation.

Transom- I built it using resin and mat to bond my sheets together. I bedded it using my own PB mix (resin, cabosil, chopped fiber, talc). Filleted everything with the same. Then I tabbed with two layers of CSM and a layer of roving, covered everything with a layer of CSM, layer of roving to add bulk and then covered everything with a final layer of CSM.

Deck- Coated underside with resin and surfboard cloth. Bedded using PB mix and bonded to the stringer tops using stainless screws and epoxy (bonding only) I tabbed the edges using a layer of CSM and roving tape. Then covered using overlapping layers of CSM and roving and topped it off with a final layer of CSM.

Finishes- Bilge is unfinished (no gelcoat or paint). Transom and deck got coated with waxed gelcoat using a roller. Transom got primed and painted after gelcoat was prepped.

Recommedations- GET TAPES WHEN POSSIBLE, saves tons of cutting strips.

nutshell
enjoy
drewp

 

[Woodonglass]

Re: Need some clarity on 'glassin new stringers/deck

Here's some specs on MDO. It is used in Marine use as is HDO.
http://www.pacificwoodlaminates.com/img/PDFs/PlywoodGuide.pdf
I'm just sayin...

 

[swire]

Re: Need some clarity on 'glassin new stringers/deck

I'm getting ready to do the same type of repair job on my 19 1/2 foot fish and ski. There seems to be a lot of different information when it comes to this type of project. Some people say 1 layer of 1708 is strong enough for stringers yet others recommend 3.

When it comes to making stringers out of plywood, what is the best way to join the plywood together to get a stringer long enough? My stringers will be about 15 feet long, plywood is only 8 feet, so how do I make a strong 15 foot stringer?

According to the info on fiberglasssite.com 1 gallon of resin will wet out 4 square yards of biaxial mat 1708. My estimated coverage area is about 150 sq ft, which means I will need over 4 gallons just to wet out the fiberglass. Does anyone have any idea how much resin the wood for the stringers and deck will soak up?

 

[dude11]

Re: Need some clarity on 'glassin new stringers/deck

According to the info on fiberglasssite.com 1 gallon of resin will wet out 4 square yards of biaxial mat 1708. My estimated coverage area is about 150 sq ft, which means I will need over 4 gallons just to wet out the fiberglass. Does anyone have any idea how much resin the wood for the stringers and deck will soak up?

This I do know--words or terms are sometimes taken wrong or not fully understood.When you get ready to wet your whatever,deck,transom,etc.First coat the work with resin and let it dry,then if wanted coat it again,and let it dry.Then wet it,apply cloth,mat or whatever your using and wet it.Sounds crazy,but I missed a step somehow by not fully understanding the process.What you will get if ply doesn't have a first coat is a dry spot in the final product.The reason is dry ply will suck up resin too fast for the mat to bond correctly.Then you get to grind it down and start over.If this isn't up to most folks standard,then by all means correct me. BTW,Mine is a 14'open hull fishing rig.Just the deck and transom and tabbing down one ped.seat,one livewell and it took 4 3/4gal.resin.And I didn't waste any.

 

[series60]

Re: Need some clarity on 'glassin new stringers/deck

Do yourself a favor and read these pages. Short and to the point for most rebuilds. It will tell you how to make the joint for long stringers.

 

[Yacht Dr.]

Re: Need some clarity on 'glassin new stringers/deck

Do yourself a favor and read these pages. Short and to the point for most rebuilds. It will tell you how to make the joint for long stringers.

IMO.. Poly will work with Anything related to any repair on your fiberglass built boat if the PREP work is done correctly ( aside from varnishing or woodworking ).

Epoxy will fail if the prep isnt done correctly....

Marine grade Ply is best..but others can be used in a pinch.

I still think that using 1.5 oz mat first for your lam schedule is Best..

YD.

 

[ondarvr]

Re: Need some clarity on 'glassin new stringers/deck

Like YD said, polyester works fine when doing repairs, In my many years of building parts and doing repairs I don't remember having bond failures like some of the epoxy only crowd always talk about. There are some situations where epoxy will do a better job and should be used, but in repairing 30 year old ski boats its not required.

 

[drewpster]

Re: Need some clarity on 'glassing new stringers/deck

Re: Need some clarity on 'glassing new stringers/deck

I keep a little epoxy around to do jobs that require the best bond. I use it for making fairing puddy and for bonding parts. I used epoxy to bond my battery mount and my seat mounts to the deck. Those parts were then covered with polyester and glass to make them watertight. I did it this way to minimize the amount of fiberglass tabbing around these parts. The idea was to minimize the finishing work needed to hide the tabs.
Epoxy has its place, but poly is best for doing the major work in my opinion.

 

[dccordell]

Re: Need some clarity on 'glassin new stringers/deck

Wow thanks for all of the responses! Sorry I'm a little slow on the reply.. it's been a busy weekend! I think I have a pretty darn good idea of what I need to do to get started. I think uscomposites is still the best in price that I can find so far.
The resin I need is just the EB general purpose type right? I notice it is the cheapest coming in at just over $100/gallon. I suppose I'll start with 10 gallons of resin and probably 20yd of glass.. does that seem way too much or too little? The boat is 18' long and about 7' at the widest point and has 4 stringers.
I would really like to do epoxy but I would like to put the extra money that I'll save on some other part of the boat. There still seems to be mixed reviews on using poly or epoxy so I guess I'll just have to test it myself to find out hah!

I checked out Lowe's today for the 3/4 ply... they didn't have any Ext. 3/4" so guess I'm gonna go try out Home Depot tomorrow. I was just curious about resin prices there... ouch!! Quite a bit higher than usc.. I'll have to ask about the MDO ply too..

How much luck do u guys have on reusing the plastic squeegees to spread the resin around? I'm just wondering how many I should order because they seem to be cheaper on usc than at the local stores, as well as the mixing buckets, rollers, etc...

Thanks for the Boat Builder Central link.. I have actually read quite a bit on their site, it's great!! I guess the most confusing this is reading one thing on that site, and then reading ten other ways to do that same thing here! Just goes to show there is more than one way to get good results (some better than others).

I'll make sure to post pics as I get this project going...

 

[dccordell]

Re: Need some clarity on 'glassin new stringers/deck

So I went ahead and sent in my order to USComposites for 10gal or resin and the fiberglass, then I noticed on their site that more than one 5gal bucket of resin has to be shipped freight and only to commercial locations. Well, that counts me out. So am I limited to only ordering the resin by the gallon? Seems to me that shipping would become outrageous doing that???

I checked FiberglassSite and they won't even ship it in 5gal containers because of the shipping being so high after HazMat fees. So I put in 10 1gal buckets of resin and the shipping for that is $136... wowzer!

So am I missing something here or what? Is there an easier way? I've been searching all over for a place here in town or even a town close by that sells resin but no luck so far. Only the auto shops and that stuff is extremely pricey there! Idk.. kinda bummed about this so far.. I went ahead and sent in my order to usc and selected the option to call for shipping and payment. I'll see what they say over the phone.

Any advice here?

 

[Woodonglass]

Re: Need some clarity on 'glassin new stringers/deck

Hey DC,

Doncha know anyone that has a commercial address that would let you ship to them? Ask some of your friends or relatives there has to be someone that could help you get around this bump in the road.

I'm just sayin...

 

[Yacht Dr.]

Re: Need some clarity on 'glassin new stringers/deck

I dont think there is any way to get around the shipping cost of hazmat.

The only way I can think of is having a buddy that buys in 55 drums and gets it at a Great discount.

But thinking your going to buy from USC or CCP without somebody Absorbing the shipping cost ( we ALL have to pay it ) is more likely not a case about an address..but some money..

There is a reason that resin costs so much..just wait till gas tops 3 bucks again..you will only get your price on resing BYE THE DAY ONLY ..

Go to your nearest boat yard and make some buds .

YD.