Parting out H170 in AZ

[BobbyFunn]

Thanks for answering my questions.

The hydroturf doesn't sound like a solution for me if it retains water. Lots of birds seem to use our boat for target practice on their flybys so I usually have to wipe things down before sailing and we have been getting much more frequent rainfall for the last several years (record high water in Lake Ontario this year). The primary reason I would do it at all would be for increased comfort and sitting in soggy shorts doesn't seem to fit that bill

Sorry to hear about the delam thing.

Seadeck might be better for seating as it is actaully closed-cell. More expensive though. Hydroturf is better for underfoot. In a cooler climate maybe more so. In south Florida even on New years day we can sail barefeet and enjoy a cool wet surface for the feet. The sun will cook the seats dry in no time. Up north, i wouldn't tolerate wetbutt either

When storing the boat is yours mast up? If so take the boom down at the end if the day. That will keep most birds away. Osprys love hanging out on the sail covers and puking fish guts all over, and other birds can hang out on the boom. By eliminating the elevated horizontal hang out they look somewhere else.

Im bummed out about the hydroturf issue so can't recommend anyone do the same unless the color is white.

Super tempted to cut the rubrail off and cut the luran off the entire top section, then pkace FRP over the foam. But that seems like work.

I love the overall 170 design, just that %!&# ACP has got to go.

When it cools down Ill invent a better way to correct the delamination.

I noticed when putting gorilla glue in the bench delamination access holes that using compressed air to blow the glue around caused the space to fill like a balloon, causing further delamination..I suspect that over time the adhesion across the entire deck weakens. I wonder if we can get glue to spread better using a vacuum as if FRP vacuum bagging. Pressurize the luran to break the weak adhesion area, pop a couple holes, then draw it back to the vacumn. Might be hard to gurantee a tight seal or locate vacuum leaks.

 

[Hunter216]

I noticed when putting gorilla glue in the bench delamination access holes that using compressed air to blow the glue around caused the space to fill like a balloon, causing further delamination..I suspect that over time the adhesion across the entire deck weakens. I wonder if we can get glue to spread better using a vacuum as if FRP vacuum bagging. Pressurize the luran to break the weak adhesion area, pop a couple holes, then draw it back to the vacumn. Might be hard to gurantee a tight seal or locate vacuum leaks.

It’s interesting that the air pressure would deform the Luran skin like that but I’ve struggled to get the hatch open on my 216 on really hot days so something is expanding and I’m guessing it’s the Luran.

I can’t visualize how vacuum would spread the glue (need to soak on that for a bit) I can see how it would pull the Luran and foam together but you can push it down with weight so......

 

[BobbyFunn]

I think i have an elegant solution to the "buckle delamination" issue for composite sandwiches. This applies specifically to Hunter's ACP construction, but it would work for almost any laminated composite. The outer surface and the core must still be in good condition. In this scenerio the outer layer is simply debonded from an intact solid core.

Typical Solutions:
1. Remove the outer layer and lay a new outer layer.

2. Drill small holes and inject adhesive between the core and outer layers.

Method one involves high cost of supplies, requires experience with fiberglass layup, and the quality of the repair depends on several factors. This repair is considered the most reliable if not potentially the least attractive. The final appearance depends highly on the skill of the petson making the repair.

Method 2 is less expensive, but also the least reliable since it is difficult to determine how well the injection is distributed between the outer layer and the core. The repair is suitable for small sections. The holes need to be refilled and faired. The entire surface is sanded and faired. Once the holes for injection are made the material is lost and must be replaced.

The solution I propose allows for maximum recovery of the outer layer and maximum access to the adhesion space between the outer layer and the core.

If we assume that the debonding of the laminate is due to buckling and low quality adhesion, then the cure is to remove a small portion of the outer layer so that the layer can expand and contract again after the repair.

The proposal:
A combination of method 1 & 2.

Given an area of delamination, remove approximately 40% of the outer layer in standardized shapes and sizes, attach the main outer layer to the core, then, reattach the standardized cutouts. After filling in the gaps, fair the surface and repaint as desired.

For a 1 square foot surface, five 4" holes will cover 43.6% of the surface. Once the discs are removed they can be reused.

If the five discs per sqft are evenly spaced the remaining "connective" layer is readily accessible for applying adhesive to nearly 100% coverage btween the cutout sections. Once cured the discs can also be reattached with 100% adhesive coverage. The remaining gaps between the main layer and the discs are small and easily leveled.

The repair requires no new laminating material. In the case of a small damaged outer layer a flat section of FRP could be prepared offsite and new 4" discs created.

What could go wrong?
The adhesive and gap filler might either be incompressable or expand more than the original outer layer.

The reattached discs may not set level with the outer layer.

The sandwich is not supposed to be flexible, however, the remaining "connective" layer will flex more than the discs.

Has anyone repaired debonding/delamination in this way?

 

[Hunter216]

For a 1 square foot surface, five 4" holes will cover 43.6% of the surface. Once the discs are removed they can be reused.

I did a little sketch of what I think you are saying. The disc's in the sketch are not centered very well but it provides a scale of what you are proposing. I think you are on to something as removing the disc's would let you see what your doing rather than flying blind squirting stuff in holes. Your proposal would preserve the shape of the surface area while ensuring you get the entire area to be "rebonded" covered with glue. However if the area was flat perhaps easier to remove the entire rectangle?

I would however make one cautionary comment. You would need to be careful not to crack the material left intact after removing the discs while lifting it up to spread glue. (perhaps smaller diameter or fewer discs).

 

[BobbyFunn]

I did a little sketch of what I think you are saying. The disc's in the sketch are not centered very well but it provides a scale of what you are proposing. I think you are on to something as removing the disc's would let you see what your doing rather than flying blind squirting stuff in holes. Your proposal would preserve the shape of the surface area while ensuring you get the entire area to be "rebonded" covered with glue. However if the area was flat perhaps easier to remove the entire rectangle?

I would however make one cautionary comment. You would need to be careful not to crack the material left intact after removing the discs while lifting it up to spread glue. (perhaps smaller diameter or fewer discs).

Thats exactly what i was thinking. The size of the discs and the amount of area hole-sawed off are arbitrary. The goal is to remove as few discs as possible, while having access to the connective layer. The larger the discs or in the extreme case one huge panel, the weaker the connective layer later.

For a square foot, 4 inch cut outs evenly distributed per your sketch will have a minimum connective layer that is about 1 inch wide, and a maximum of about 3 inches. In practice the cutouts would be more or less randomly distibuted to fit the area to be repaired.

If for example the repair area is 2 square feet then 10 4" disc can be used, randomly spread out.

The key to this is using standard size cutouts to "mass produce" the repair.

 

[Hunter216]

The larger the discs or in the extreme case one huge panel, the weaker the connective layer later.

I’m by no means indicating your wrong about making things weaker but I’m having trouble understanding your logic on this point.
On your sq ft example the Luran NOT removed in discs would get reattached to the foam, the discs would get reattached to the foam and the discs would get seam glued back to the Luran not removed so I don’t follow how that would be “stronger” than cutting out a sq ft of Luran, reattaching it to the foam and glueing the seam????

 

[BobbyFunn]

I’m by no means indicating your wrong about making things weaker but I’m having trouble understanding your logic on this point.

I'm wrong often, my logic is suspect, my conclusions are flawed. I should be tested.

I was thinking as if the the main strength comes from the luran not cut off.

Imagine a whole sheet of paper. If there are a bunch of small holes made randomly over the surface, then the forces can be distributed through all connected surfaces. If there is one huge cutout, the forces have to navigate around the hole, cuasing twist.

Take a sheet of paper and cut a huge hole out of it. Take that cut out and divide it into two, Cut out similar size holes spaced out on a separate sheet of paper.

Lay the sheets down on the counter. Pull any two sides out or push in with the big hole paper and youll see it pretzel up no matter where you pull apart.

Do the same with the paper with two smaller holes. The paper will only pretzel in a couple places.

The more holes (same area as original cutout) randomly spaced, the harder it is to find the place to pull the paper so that it pretzels.

Lets say the boat pieces are successfully reattached. It will be very easy for nature to find the force points that will break the repair seam with the huge cutout, more dificult for nature to find the precise location in multiple cutouts.

In an impact or "bending" scenerio, hitting the large single repair may cause a large percentage of the seam to detach. With small peices, only the small section will be damaged since the forces will stop at the seam.

Thats my storyboarding. Im open to real science.

 

[Hunter216]

I'm wrong often, my logic is suspect, my conclusions are flawed. I should be tested.

I was thinking as if the the main strength comes from the luran not cut off.

Imagine a whole sheet of paper. If there are a bunch of small holes made randomly over the surface, then the forces can be distributed through all connected surfaces. If there is one huge cutout, the forces have to navigate around the hole, cuasing twist.

Take a sheet of paper and cut a huge hole out of it. Take that cut out and divide it into two, Cut out similar size holes spaced out on a separate sheet of paper.

Lay the sheets down on the counter. Pull any two sides out or push in with the big hole paper and youll see it pretzel up no matter where you pull apart.

Do the same with the paper with two smaller holes. The paper will only pretzel in a couple places.

The more holes (same area as original cutout) randomly spaced, the harder it is to find the place to pull the paper so that it pretzels.

Lets say the boat pieces are successfully reattached. It will be very easy for nature to find the force points that will break the repair seam with the huge cutout, more dificult for nature to find the precise location in multiple cutouts.

In an impact or "bending" scenerio, hitting the large single repair may cause a large percentage of the seam to detach. With small peices, only the small section will be damaged since the forces will stop at the seam.

Thats my storyboarding. Im open to real science.

So great visualizing description of your logic! I understand where your coming from now.

I am far removed from being a scientist so anything I say is subject to serious BS review

I would say that if you were only dealing with a single layer of any material your logic holds true. However because the Luran would get re-attached to the foam it would again be part of the sandwich and not act as an independent layer as long as delamination does not reoccur. In fact any one of the layers FRP, foam and Luran are not very strong by themselves and would easily deform under loads, combining them is a whole different beast.

You are likely correct to have some concern about the seam in the Luran cracking under load (sort of uncharted territory). However based on your testing of the bonding strength of the PL - Luran - foam I don't believe it will delaminate again so is the MMA glued seam likely to fail. Probably not

To minimize the number of discs to be removed have you given any thought to making some kind of glue spreading device where you could remove a small disc in the delaminated section that lets you insert the applicator "tool" between the Luran and foam? Lets say the applicator is a somewhat flattened stiff tube with holes in the top and bottom areas. You insert the "tool" in the disc cutout and push it into the delaminated area, inject enough PL to fill the tube so it comes out the holes and then move the "tool" around adding more PL so your sure it gets the entire area you can reach saturated. For irregular areas you move the "tool" in and out of the disc cutout. Maybe the PL doesn't lend itself to that idea because its too thick or sets up to fast???

 

[BobbyFunn]

Its been about a month of intense Florida sun on the repaired deck. So far so good. No changes from the first week.

This picture is from Sarasota Bay looking at New Pass. I was out single handing in 5-15 mph winds. Kinda hot to be out, but no regrets. (You are seeing pine needles on the deck)

I studied the areas that bubbled up and have found that areas that have been repaired with Loctite PL3X are still firmly attached. the area on the seat that i fixed with gorrila glue delaminated in one area but not another.

Im thinking the factory adhesive just isnt that great after all this time 15 years?

I wish i had better results with gorilla glue on the bench. I took the time to add moisture and used compress air to blow the glue from one access hole to another. So one area has failed in heat.

When adding the loctite i injected it in 8 directions from each 4" hole (shoved most of the nozzel under the luran eah time), and then used a kabob stick to smear it around and force it a little bit farther back. That seems to be holding up.

Its hard to know if enough gorilla glue was applied. It possible that the compressed air blew it around, but also spread it too thin and possibly just spread it out into random specs or spiderweb like strands.

I would like to do research on luran and MWA adhesives in the foam/luran layer.

Anyone want to donate a hull for the cause?

 

[Shorefun]

Too much work is what I have decided. The construction adhesive is probably not too bad a solution. It is good and sticky and flexible.

Drill small holes and inject something like 5200 or maybe Loctite stuff. You your hands to move the adhesive out further. Do a bunch of spots.
Fill holes with MA300.
Go sailing.

If you want to push the boat hard, you might really want to consider a different boat.

 

[Hunter216]

Its been about a month of intense Florida sun on the repaired deck. So far so good. No changes from the first week.

This picture is from Sarasota Bay looking at New Pass. I was out single handing in 5-15 mph winds. Kinda hot to be out, but no regrets. (You are seeing pine needles on the deck)

View attachment 167425

I studied the areas that bubbled up and have found that areas that have been repaired with Loctite PL3X are still firmly attached. the area on the seat that i fixed with gorrila glue delaminated in one area but not another.

Im thinking the factory adhesive just isnt that great after all this time 15 years?

I wish i had better results with gorilla glue on the bench. I took the time to add moisture and used compress air to blow the glue from one access hole to another. So one area has failed in heat.

When adding the loctite i injected it in 8 directions from each 4" hole (shoved most of the nozzel under the luran eah time), and then used a kabob stick to smear it around and force it a little bit farther back. That seems to be holding up.

Its hard to know if enough gorilla glue was applied. It possible that the compressed air blew it around, but also spread it too thin and possibly just spread it out into random specs or spiderweb like strands.

I would like to do research on luran and MWA adhesives in the foam/luran layer.

Anyone want to donate a hull for the cause?

Good to hear the Loctite areas are holding up. It appears that your testing (initial and now field) are showing that it works to bond Luran to foam. I’m not sure of the temps but after a month of baking and sailing in Florida sun if it’s going to fail it would have by now, after all it is “construction adhesive” with a extensive track record. That’s the stuff I will use if/when I do a repair.

The approach to get the Loctite in place will always come down to how the user wants to approach the job. Personally I would choose to tackle this once and be done so making “injection” sites large enough that I can “see” that I have all the areas coated would be important to me.

Now you gotta work on getting that spinnaker!

 

[BobbyFunn]

Now you gotta work on getting that spinnaker!

This is the deciding factor to keep the boat or not for me. I've determined that a fractional rig without some sort of downwind sail is "incomplete".

What I lack is a bowsprit and a deployment system that could easily be handled by the jib crew. I slobber all over myself looking at the Weta trimarans and the RS Quest. The Weta has a furling spinnaker and the RS boats have a system that pulls the sail down and back into storage.

The factory bowsprit for the 170 is a no-go IMO. I load on the trailer and there is no way that design won't get trashed at the trailer bow stop. I have said before the bow eye for the 170 should have been placed just a foot or so above the waterline so that it can be loaded on a trailer like a powerboat versus rested on the trailer like a keelboat. The trailer is wetted until the middle bunks are sunk, and then the strap pulls the boat up to the bowstop (still working on a system for a wide roller under the bow versus a "mini bunk"). Usually, the bow eye just barely rises above the bow stop until the trailer is pulled completely out. Then the bow angles off about 1 inch away from the bowstop. The factory bowsprite would bang into it and I don't want to be messing with the installation and removal as an added step to go sailing. If the bow eye was in the lower location the bow stop and crank would be lower like a real boat and the crank would pull the boat straight up the trailer and out of the water. This would also open up the area around the bow rub rail for the factory bowsprite; if it didn't also then bang into the mast support.

The newer hunter 18 has the better solution of having the bowsprite cut in to the top deck and fitted in the cuddy cabin. It is retractable and away from the rub rail when retracted.

Its rare to sail downwind anyways for me so it's not a total loss. I still get to go sailing!

 

[BobbyFunn]

Too much work is what I have decided. The construction adhesive is probably not too bad a solution. It is good and sticky and flexible.

Drill small holes and inject something like 5200 or maybe Loctite stuff. You your hands to move the adhesive out further. Do a bunch of spots.
Fill holes with MA300.
Go sailing.

If you want to push the boat hard, you might really want to consider a different boat.

@Shorefun you ever place the MA300 between the foam and the luran? I noticed when I filled some drill holes for the bench the JB weld plastic welder bubbled up. Does the MA300 do that?

 

[Hunter216]

This is the deciding factor to keep the boat or not for me. I've determined that a fractional rig without some sort of downwind sail is "incomplete".

What I lack is a bowsprit and a deployment system that could easily be handled by the jib crew. I slobber all over myself looking at the Weta trimarans and the RS Quest. The Weta has a furling spinnaker and the RS boats have a system that pulls the sail down and back into storage.

The factory bowsprit for the 170 is a no-go IMO. I load on the trailer and there is no way that design won't get trashed at the trailer bow stop. I have said before the bow eye for the 170 should have been placed just a foot or so above the waterline so that it can be loaded on a trailer like a powerboat versus rested on the trailer like a keelboat. The trailer is wetted until the middle bunks are sunk, and then the strap pulls the boat up to the bowstop (still working on a system for a wide roller under the bow versus a "mini bunk"). Usually, the bow eye just barely rises above the bow stop until the trailer is pulled completely out. Then the bow angles off about 1 inch away from the bowstop. The factory bowsprite would bang into it and I don't want to be messing with the installation and removal as an added step to go sailing. If the bow eye was in the lower location the bow stop and crank would be lower like a real boat and the crank would pull the boat straight up the trailer and out of the water. This would also open up the area around the bow rub rail for the factory bowsprite; if it didn't also then bang into the mast support.

The newer hunter 18 has the better solution of having the bowsprite cut in to the top deck and fitted in the cuddy cabin. It is retractable and away from the rub rail when retracted.

Its rare to sail downwind anyways for me so it's not a total loss. I still get to go sailing!

I would agree the spin on the 170 seems to be something of an afterthought. The factory sprit looks pretty messy. Same deal on the 216, sprit retracts which is good but lots of stuff on the foredeck to trip over to. The newer FRP versions are “designed” with the sprit in mind so much cleaner and functional.

That’s being said having the spin on the 216 has made it much more interesting for me. It makes a long downwind slog entertaining as I can broad reach at speed with it. I have had reefed main only on a downwinder and it has convinced me that I’m not going to be flying the spin in heavy air. The sag in the forestay was VERY pronounced with that load. I didn’t want to use the jib so certainly won’t be launching the kite and dismast (sp) or death roll!

At some point along the way I posted a link in here of a guy sailing a 170 that had a patch job from what looked like carbon. The same guy flys a spin off what looks like a boat pole lashed to the front.

Your pretty talented in the MacGuiver area so maybe you could fashion a sprit you could take on and off easily. Lots of old two piece windsurfer masts out there. Maybe use the top half with some guy lines to boweye and somewhere aft???

If your thinking of other boats check this out
http://www.fulcrumspeedworks.com/UFO/

 

[Shorefun]

@Shorefun you ever place the MA300 between the foam and the luran? I noticed when I filled some drill holes for the bench the JB weld plastic welder bubbled up. Does the MA300 do that?

The stuff you are using is different then the MA300, I looked up the MSDS to be sure.

No the MA300 did not cause any reactions to the foam that I noticed. I applied some direct to the foam by accident. I had a long crack in the forward area that I put the MA300 on some strips of fiberglass and slipped it underneath. I wanted some strength in the long crack and I could pick it up enough to do the job. I was concerned that the foam might not respond well to the MA300 since it has that solvent smell to it. For the 15 seconds or so that I was placing the glass with glue the foam stayed solid. It did not appear to react. I know the MA300 gets the Luran slightly 'melted' at the surface pretty quick.
When I plugged the injection holes I also did not see any problems. I also did my best to force the MA300 through the cracks I ground down and did not find any reaction.

I am quite impressed with how the MA300 worked.

 

[BobbyFunn]

I would agree the spin on the 170 seems to be something of an afterthought. The factory sprit looks pretty messy. Same deal on the 216, sprit retracts which is good but lots of stuff on the foredeck to trip over to. The newer FRP versions are “designed” with the sprit in mind so much cleaner and functional.

That’s being said having the spin on the 216 has made it much more interesting for me. It makes a long downwind slog entertaining as I can broad reach at speed with it. I have had reefed main only on a downwinder and it has convinced me that I’m not going to be flying the spin in heavy air. The sag in the forestay was VERY pronounced with that load. I didn’t want to use the jib so certainly won’t be launching the kite and dismast (sp) or death roll!

At some point along the way I posted a link in here of a guy sailing a 170 that had a patch job from what looked like carbon. The same guy flys a spin off what looks like a boat pole lashed to the front.

Your pretty talented in the MacGuiver area so maybe you could fashion a sprit you could take on and off easily. Lots of old two piece windsurfer masts out there. Maybe use the top half with some guy lines to boweye and somewhere aft???

If your thinking of other boats check this out
http://www.fulcrumspeedworks.com/UFO/

I think ive seen that collection of vidoes as well. I think that guy installed backstays and changed his mainsheet to attach to the end of the boom. He looks like he us having fun with a symetrical spinaker.

UFO's! that looks like fun and a sore back the rest of the week.

 

[Hunter216]

UFO's! that looks like fun and a sore back the rest of the week.[/QUOTE

Yep hiking straps are the clue that things are going to be sore the next day

 

[BobbyFunn]

The 170 is back in the garage. Its too hot to be out and I really want to fix the deck and seat warping. The goal is the have the benches and the floor better than new in time to enjoy the fall, winter, spring season.

The Florida sun is merciless. In just 3 months the darker color if the hydroturf ravaged the Luran plastic. The repeated expansion cycles have not only warped the surfaces, but have introduced parallel cracks and discolored the surface.

I have a few observations
The luran expands 3 times as much as fiberglass. The longer the surface, the more expansion there will be.

You may have read in earlier posts that I cut out 4 inch pucks out of the luran, then glued them back. Epoxy with filler was used to fill the cracks. They were all covered with the hydro turf. They all have open cracks, the cool part of this is the cracks are noticeably larger at the front and back of the disk and hairline thickness on the sides. The luran expands and warps the length of the boat. Large flat areas like the deck and benches are super vulnerable. The curved sections are unaffected. The deck and benches arent wide enough to cause issues expanding beam to beam.

It was a mistake to use epoxy with hardener to fill the gap between the 4" pucks and the connecting luran. MMA is the way to go. Every puck is still solidly attached to the foam core, and the luran surrounding the pucks are stuck to the foam. The PL3X is performing great.

The benches were delaminated and fixed during the big deck repair. I drilled three holes, poured gorilla glue in them, hit them with compressed air, then sealed them up with MMA. Those were covered with the hydroturf. They held up well without any cracking. The luran did warp about 3 inches away from the holes, so, even air blown gorrila glue doesnt migrate very far from the drill holes.

The rudder mount and motor mount are still fantastic!

So im working on a repair plan that is starting to look a lot like the original posters picture.

Plan A:
Cut 5 4" pucks per sqft and fix the delamination on the large flat horizontal surfaces. Dont think this will look good since it is hard to get the pucks level and the warped luran probably wont lay flat. I also risk expansion again.

Plan B:
Cut out the large surfaces and put fiberglass down. This will fix the delamination for the large areas, and it will be smooth. The large areas wont expand like luran so i can put the hydroturf back down.

Plan C: Skin entire top deck to foam and resurface with fiberglass.

 

[Hunter216]

Wow
It’s good to know at least that your structural repairs are all good. As you point out it is interesting that all of the cracks are at 90 deg to the length of the boat. I wonder if this has something to do with the normal flexing on the long axis of the hull as you sail. The Luran might have changed state a little due to repeat high temp / cool cycles and is a little more brittle, hence the cracks.

Sounds like you have 3 valid approaches.

If you reapply the hydro turf will you choose a lighter colour or maybe if it’s FRP it wouldn’t matter. The blue is a cool colour!

 

[BobbyFunn]

If you reapply the hydro turf will you choose a lighter colour or maybe if it’s FRP it wouldn’t matter. The blue is a cool colour!

I absolutely will be putting the hydroturf back on. There are a couple more lessons learned here as well.

The 3m spray jets out of the can like webs from spiderman's wrist. I covered both surfaces, but in reality the coverage was just webs. The next time it is applied i will use a brush or roller and use good ole fashioned contact cement. The surface wont be luran anymore so i will have more options.

I think i will cut the large panels off. Everyone who posted earlier on has really good ideas for the fix. Im sketching ideas for the install. I think i know what the "trick" is, sort of.

Before laying the fiberglass down i will seal the luran with packing tape so that the layup bonds to the foam and incidentally touches the luran. I will then cut/sand/remove any extra that touches the luran. At this point im thinking take a grinder and create a "crack" around the fiberglass. This gap between the fiberglass and luran would be repaired with MMA just like the repair documentation. Just not sure of what the bevel between the luran and layup should be, use biaxual tape in a recessed cut?

Ill need to review the repair documents again. I cant just fit the layup on the foam and assume the edges around the layup will stay together.

Also not sure if i should use resin or epoxy. Both are safe for the foam but resin might be better for the surfaces horizontal to the sun.