laying up 1708 a lot

[WalterG]

I am covering my peeled hull with 1708 biaxial cloth and epoxy. It will take 3 rows of 1708 to get to the waterline or bottom of the keel depending on which way I go.
Is there a best way to go? Start at bottom and overlay the next row would be starting with the shortest piece first 10'8" long, easiest to manipulate. Or start at top and have the overlap with the bottop row over the top. That would probably be the trickiest because the top row is 24ft long.

 

[Woodonglass]

Re: laying up 1708 a lot

I would suggest posting some pics so we can see what you see. Hard to help when we're shooting in the dark.

 

[Yacht Dr.]

Re: laying up 1708 a lot

Hello Walter and Welcome to Iboats ..

Please read this .. http://forums.iboats.com/showthread.php?t=444084

What boat do you have .. Why did you Peel it .. why are you glassing with 1708 ? .. Kinda Thick lam for a peel job IMO.

I would think that even a 1.5 oz mat cover is not needed if you have a proper peel job ( I have never lammed a complete hull with mat .. or even considered 1708 ).

Is there more to this project then your initial post ? ..

NEED PIX .. and more information on what/why your doing ..

YD.

 

[oops!]

Re: laying up 1708 a lot

hi walter.....welcome to iboats !

im not really sure what you are doing and why.

usually if a hull is bad on the outside, 2 layers of csm are more than enough to make the hull good enough to get to where it can be re gelled.

1708 is really heavy stuff for the outside..., unless using the thickness to bring the repair to flush

please post pics and let us in on your thinking.
possibly we can save you a lot of time and money here

cheers
oops

 

[WalterG]

Re: laying up 1708 a lot

Greetings and thanks for the replies.
My boat is a 32ft Nantucket Clipper, sailboat. She was built in 71 and had suffered from many weeping blisters whenever on the dry. The original owner peeled or ground away the gelcoat and outer fiberglass to expose all blisters. She sat in a barn for 10 years and is nice and dry now. I am restoring this boat to maximum strength because I am planning to sail blue water and since she is ground down now I want to have no doubts about what is between me and the ocean. It may be overkill but I'll sleep better. 1708 with epoxy will give me the security I want and hopefully prevent future blister problems as long as my work is good.
There were some places in the keel where resin had not saturated the fabric. I have ground out those places, patched and faired. All of the blisters are ground out, shallow ones I filled with cabosil and epoxy. My 1708 is 27" wide and the hull will take three layers to cover from the bottom of the keel to the remaining gelcoat.
The photos are when I moved it out of the barn then in my yard. I'll load some close shots of the work.

 

[Woodonglass]

Re: laying up 1708 a lot

Well, With OOPS and Yacht Doctor on this, You have two of the best to help you. Good Luck with your project.

 

[Yacht Dr.]

Re: laying up 1708 a lot

1708 will not get you were you want to go.

I see no reason for even a layer of mat on the bottom.

Put 5 coats of IP 2000 and a few coats of VC-17 and your good to go ( after any blister repairs are made ).

I would Love that boat and put my Family on that to Cruise if you know what I'm sayin' ..

YD.

PS. Unless you have pics of a full bottom strip down to the glass ..

PSS. Start researching Interprotect 2000 and its application windows for VC-17. .. thats all you will need if done right

 

[ondarvr]

Re: laying up 1708 a lot

From the pic I see what looks like white and maybe green (?), I assume this is the filler and fairing compound, I just don't see any bare glass.

If they did grind down into or through the first layer of glass then its best to replace it, you don't really need to use 1708 unless they removed a great deal of laminate, but it can be used if you if that's the way you want to go. It will be somewhat tricky to use that fabric upside down though, especially for a rookie, you may end up wearing some of it as it falls off, so keep your head covered.

It sounds like you already have the 1708 though.

You will need to use relatively short lengths of material for a couple of reasons.

1, it?s not going to conform the hull shape all that well when using long lengths.

2, it can be a nightmare to work with that much glass and epoxy at one time.

Doing it from the inside, like in a mold when it was first built, would be somewhat easy to do in full lengths, even with a heavy fabric, but from the outside?..

I think a cloth (10 oz or so) would be plenty, and easier to work with, you could even use two layers if you wanted.

 

[Woodonglass]

Re: laying up 1708 a lot

Not to mention that epoxy could have a problem with the mat attached to the backside of the 1708 and could cause bonding issues.

 

[WalterG]

Re: laying up 1708 a lot

Thanks to all who have chimed in.
I do not know how much fiberglass was removed when it was taken down so I am Ok with adding some thickness. The original owner died after the hull was mostly stripped so I'm dealing with a lot of unknowns. At least he did a smooth job and has made it easy to grind out remaining blisters and areas that sounded thin with resin. Also, this is no racer so weight in the hull isn't a bad thing.
I am planning to apply the biax with backing paper that I have gotten from a local sign company. Nothing sticks to this stuff. I have played with small patches 1.5ftX1.5ft rt angles filling areas that hadn't gotten resin on the keel. Laying the cloth on with the resin already rolled into it seems to work well. The weight and clusminess should be ok on the keel but the strips closer to the water line will be something else. I'm thinking that will require rolling a line of resin the length just below the waterline. apply the cloth and duct tape the top line, roll more epoxy into the cloth and when the 32oz/yd is on it, slap the backing paper on and roll out the bubbles. The backing paper leaves a nice smooth finish.
This is my second boat to rebuild. The first one, (free Ha Ha Ha), needed recoring the entire hull, fore and aft decks. Some wood work too. I did learn to hate balsa coring, how to mix resin and wet down mat, I just never connected rows of cloth. I have always tried to use one piece if possible.
This biax cloth I have is a little different. It has cloth on both sides with the fabric grains angled and sewn at 45 degrees. It is suposed to conform to curves. It is my first time to use it so I'll find out. Our temps are close to 70F most of the day so it should give me a decent work time. I guess if I don't like the way the rows join, I could add some cloth over the joint.

Thanks for all the advice. I'm going to get this thing covered one way or another. One thing about glass, if I screw it up, I got a grinder.
I'll post some more pictures and share the experience.

Walter

 

[ondarvr]

Re: laying up 1708 a lot

1708 refers to the weight and type of product it is, 17 is the weight of the two layers of uni that are laid at 45 degrees (Biax) and then stitched together, the 08 is the CSM (chopped strand mat) that is stitched in place on one side of the Biax. If you have only the two layers of uni then you have a 17 oz biax. or 1700. Not every supplier has the same terminology for their glass though.

Depending on the style of stitching, the product you have will vary in how well it conforms to the surface, again different brands will perform differently.

Epoxy is a little trickier to work with than polyester, it tends to drain out of the glass easier, yet can be more difficult to wet out the glass with, so it kind of gets you from both ends. I?m not sure what the backing paper you plan to use is like, but many times this type of method can make it more difficult, not easier, it may help hold the resin in the glass better though.

 

[oops!]

Re: laying up 1708 a lot

Walter.......

you are dealing with a very difficult situation here.....osmosis. or sometimes called boat pox.

it seems you are doing the full repair correctly.....with a full grind and glass...and an epoxy barrier.

the boat has been sitting for 10 years.....so....it may work..however...it may return....

may i suggest....you keep grinding.....every speck of gell that is left.....is a possible problem....

im gonna shut up and watch now.......and let ondarvr help you with this.....every thing he has said is bang on.....glassing upside down... everything.
i agree with your approach......to re glass as osmosis situation....because you are going with epoxy...(the correct choice for this) you realize...gellcoating is out....your only option is paint. thats not a bad thing....but the only thing.

ondarvr is one of the top pros in north America with this....so you are in the best hands.....

yd suggested some products....i am not aware of them.....Ondarvr will be able to attest to their worth in this application. their is no miracle cure so keep in mind.....this repair may....or may not work.

cheers bud....nice boat.....im watching
oops

 

[WalterG]

Re: laying up 1708 a lot

Thanks for clearing up the biax ID. I do not have 1708 but a 17oz biax. I'm still grinding and filling holes. This is arm breaking business. I'll try to keep up with photos of the process.

Grinding does teach you a lot about how your boat was built. The peel/grind job did remove the gel coat(outer layer under paint), The next thick layer is also blue but filled with fiberglass mat, filler is under that and the grinding stops at the next layer of glass. I am finding some delamination there too. Sometime you come to a point where you have to quit grinding and build it up. That is where I am. Maybe a little more, I'm not doing this again on this boat. I'v got Aerosil/cabosil to fill some of the delamination and maybe an extra layer of biax if it takes too much grinding.

Walter

 

[WalterG]

Re: laying up 1708 a lot

View attachment 119018View attachment 119019View attachment 119020View attachment 119021
My hull is ground down, patched, covered from the top of what will be the bootstripe down with 17oz biax that is well soaked in epoxy. I still have some fairing, sanding and painting left but all the bad glass is now good.
My methods included a combination of applying resin to get tacky on the top line and laying the biax on it to get stuck down with a wet roller, using backing paper to apply smaller pieces and patches then roll over the backing paper, holding the resin and leaving a nice surface and just plain wrestling wet glass in the wind which was the most strenuous by far and ended up being done with backing paper.
The big holes I patched in the keel were over 1"thick. I ground out grooves lengthwise through the holes and alternated between laying in lengths of 17oz cloth, resin, random pieces of heavy fabric and more resin and cabosil. I lost count of how many layers to build up so thick. I tapered out the hole to 12" diameter and finished it out with more biax inside and out.
My cloth laid up in full lengths, 25', 18' and 12' at the bottom of the keel. I had a helper for the longer pieces which went up easily as long as we waited patiently for the resin to get tacky. I can't say enough about how great my helper was. She mixed resin, stayed in front of me supporting the cloth and keeping the top line straight and never complained.
I decided I could do the bottom pieces, 12' long, alone. Big mistake. One side was in the shade. I did it first, applying the resin and let it set for 30 minutes while I wrapped a 2' piece around the back of the keel. The mistake was that the resin on the back piece was wetter than the tacky area and the cloth refused to hold. Every time I was rolling out the hanging area under the front of the keel, the top aft corner would fall. As I ran around to the stern the fwd piont would fall. It kept me running until I used my backing paper to hold it in place. The last piece on the sunny side went up like a dream. There you go, be patient, have good help and stay in the sun.
Next comes fairing and painting.

 

[Yacht Dr.]

Re: laying up 1708 a lot

I still do not see any indication of a full peel job ? .. Am I missing something there in your pics ?

Putting glass on some kinda of filler is potentially a bad idea ( pics show filler on over 50% of the working area ).

Also.. you should get your helper a pair of Safety glasses when working with this stuff ..

I would still recommend using some interprotect 2000 or a few coats of epoxy for your final "barrier" coat before applying your Bottom paint ( still recommend vc-17 from interlux .. best stuff out there for sail boats ).

Oh.. and as far as adding extra weight .. your a displacement hull .. you can only go so fast in the water depending on how much hull you have in the water. Might .. just might be a good thing depending on the hull design .

Keep them pics coming ...

YD.

 

[BWT]

Re: laying up 1708 a lot

Phew, first post in a while for me; Fall is a busy time trying to beat old man Winter I've been meaning to chime in on this but haven't gotten to it until now.. Like YD said I don't think the hull was ever peeled. It's UN-mistakeable in the appearance when it is. Looks more like it was given a good sanding (removed bottom paint, some gel and possibly some old bondo from previous repairs. My initial thought was to go the route of applying a barrier coat, bottom paint and call it done. The IP2000 is an epoxy coating with a high level of platelets (think of them like microscopic shingles) that prevent water permeation. BUT, since the additional glass is already in place lets focus on where we're at to move forward.

I don't think that it's a bad idea that the hull was beefed up especially if you're thinking of doing some blue water cruising, but I think you may have added a little more work for yourself to get the hull where you want it. IMO, from here I would sand the hull down with 60 grit to smooth things out a bit (but most importantly to scuff the surface real well for the next layup). Then, clean the hull and start fairing in the glasswork with some thickened epoxy (my pref is west system and 410 filer). Mix it thick and apply with a trowel (like doing drywall mudding). Go over the entire area with probably 1 heavy coat or 2 medium coats. Then don the bunny suit, respirator and have a good stack of sandpaper (80 grit) handy. Keep the sander moving and level the hull down until it is uniformly smooth. If you're really ambitious the next step would be to long board sand (by hand) the entire hull to get everything fare and dynamic for gliding through the water.

Here you have a fork in the road; either go forward with a barrier coat (IP2000) and bottom paint, or go over the hull with a good paint and call it good. Personally I would just do the bottom paint as the glass and fairing compound were / would both be done with epoxy; kinda a barrier coat in and of itself However to seal the pores of the 410 filler after sanding might not be a bad idea to roll on an un-thinned coat of epoxy (then sand again). Seems like there's an awful lot of sanding involved with bottom jobs BUT, when finished it will look like new (and hopefully stay that way if all the prep prior to glass layup was done)

FYI, one tip I've used for laying up large sheets of glass is to tack the material onto the hull dry using a dusting of 3M spray adhesive. This keeps everything in place, prevents it from falling on your head half wet and it doesn't have any effects / reactions with the resin or epoxy. It's used in resin infusion applications quite a bit..

Hope this helps! Good luck!

~BWT

 

[WalterG]

Re: laying up 1708 a lot

Greetings All,

The description of the hull from the widow of the previous owner was that it was peeled. It was probably more likely ground down but was done very evenly over the entire lower hull. The last picture I posted is what I started with, taken very close to the top work line. Just above the picture would be paint, below that is blue gel coat and you can see fibers of mat in the blue which has been removed. There is some kind of filler layer below the blue which is badly pocked. Before I laid up my biax I sanded down to where I could see more fibers and fill any delamination or blisters. It was easy to tap the surface and hear pockets of delamination. The picture that shows some backing paper is where I sanded deeply into the aft section of the keel into the next layer of glass and built that area up with a second layer of the 17oz biax.
I do have a lot of sanding ahead of me. My pneumatic orbital sander is prepped and ready to go. I have a thickened epoxy product made by a company called Durall that I used on three other projects including my last complete recoring and bottom job of my daysailer and has held up remarkably. It rolls on easily and smooths out nicely so it always looks wet and finishes as hard as porcilin. They make an anti-fouling epoxy bottom paint that contains teflon and I'm planning to use it. The company says it is good for 10 years and they have always been straight with me before. More pictures will come. I'm glad to have gotten the foundation laid before more bad weather has hit. Our temps hit mid 20s last night. This year has gone straight from freezing to floods to 100F to a short nice period back to freezing again. My schedule is to get the bottom finished, engine overhaul finished and reinstalled, rudder built and boat ready to launch by spring.

Walter