1980s Coastworker 180 transom core replacement questions/advice sought

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Well, I decided no point wasting time and after getting the kids settled down in bed tonight I got busy with tape measure, marker pen, drill, and jigsaw.

I'll start by saying that the quality of this tub beneath the surface is surprising, but not in a good way.
I'll mention also right now that the people who make these boats now are not the same people who used to build them, so I'm in no way commenting on the brand or suggesting anything other than purely what I am currently finding in my own boat.

So....
The first cut I made was inside one of the rear storage lockers since they're directly above one of the deck support grid bits:

You can see a big crack there and I was able to grip that piece and waggle it around!!
Same on the opposite side, and the bracing piece was actually only still held in place by about 2cm of CSM that hadn't come apart yet.
Didn't take much effort at all to just pull the whole piece out!! So this was evidence that it really hadn't been secured/glassed in properly in the slightest.

Inside this piece there was a bit of foam, but not right through it. As I poked around there, it became apparent that the two main front to back 'rails' that the deck is bonded onto, are just hollow fibreglass section with no foam/wood etc inside, and very badly glassed in.
Most of the bits I had access to had big loose pieces of fibreglass that move around freely when you prod them. It's incredible, and I can only assume has always been like this, because a lot of this stuff doesn't appear to have torn, snapped or whatever.

Here's more examples of what I mean:

I've cut six holes out tonight - two in the rear lockers over broken brace bits, two inside the seat pod, and two on the open deck over the midships braces (also broken). Each hole is roughly about 12-15" by 8-10" or so and gives a lot of access to glass things up nice and strong, and to get dodgy bits out.

I'm certain I'll need to make more holes further forwards, and possibly to enlarge them in some places. Shame to spoil an unscathed deck but needs must, and I have plans for hiding the scars once she's fixed up...

Now this boat is what they describe as 'near unsinkable' and it all comes down to a load of encased buoyancy.
The space beneath the deck is more or less rammed with gallon containers but it's all flawed.
I pulled out a few like this:

Some without lids, and some with pinprick holes which had soaked up a small amount of water. Can only assume they have been holes by moving and being abraded by exposed deck fittings, or sharp bits of fibreglass etc since they're enclosed so they can't have been owner sabotaged really.

I've pulled out maybe 1/4 to 1/3 of the number under there by my reckoning:

Some of the deck has ply in it, other places don't.


It might sound bizarre, but I actually feel a whole lot happier about this now that I've chopped it up a bit.
I can see loads of crappiness where glass work has either come apart over the years, or just never been glassed down in the first place.
IMHO stuff like this just shouldn't come apart, or at least not nearly so much of it like this!!

Don't get me wrong, the deck is very firmly secured in place and it may have always been like this for the most part except for where there are actual cracks and broken bits (as opposed to just not glassed down), but I think it's incredible that it's like this, and am almost excited about the fact that I'll be making it a lot more strong & rigid than it ever was.

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Just waiting for a nice dry evening now when I can start doing some glassing under the deck to strengthen all this junk now.
Kind of excited about doing it!

Sort of surprised that no-one has told me I've done something dumb though or whatever. That's not any sort of 'funny' comment by the way, I just kind of expected some might not like the thought of me cutting holes out of the deck. Doesn't matter either way!

One thing I still need to do is to investigate somehow to see if there is a forward brace across the hull that I can't yet see. My guess is yes, and that this will also need work doing. I don't want to cut random holes as it increases the work I have to do putting it all right again afterwards, so I have to somehow get access or visibility to where it might lie. Hopefully by removing more of the buoyancy tubs from under the deck I'll be able to see, then I can measure and cut the deck accordingly to get just the right level of access for carrying out a repair.

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Hi all

Have a quick question if someone can clarify for me please?

I've finally got to the point where I've begun the actual repair work stage of the boat instead of still being in the break/remove/destroy stage, so in that respect hopefully I've gone over the top of a psychological hill.

I've been glassing up some of the damaged framework beneath the deck and it's been horrible to do in such enclosed spaces (ie reaching in with airline & finger belt sander and getting sleeves full of FG dust etc), but I feel great knowing that bits of the boat that were trashed before are now strong again.

On a couple of the bits I've done, I want to add a bit more glass in places, and I'm slightly unsure about how long you can leave fresh fibreglass before it has to be ground back if adding more.

I suspect it's the case that basically as soon as it's cured, adding more means sanding/grinding the surface, but I'm sort of hoping someone will tell me it's not necessary this soon (ie within a week of adding the existing stuff) as it's a job I totally hate!

Not trying to avoid it if it's necessary - just don't want to do it if there's no real need. Probably wishful thinking though...

Thanks!

 

[Georgesalmon]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

"On a couple of the bits I've done, I want to add a bit more glass in places, and I'm slightly unsure about how long you can leave fresh fibreglass before it has to be ground back if adding more. "

One rule about adding new layers of laminate over cured laminate (as directed by the US Navy) for a primary bond (chemical) is 16 hours. After that the surface must be abraided before adding new laminate and is called a secondary bond. If we missed the primary bond time we would have to scrap the whole part. We did actually have to scrap one hull at tremendous cost. Do I really think that 16 hours max is necessary, no. I do think you could wait somewhat longer than that but not a week. But there must be something to it, we had to stager shifts to accomplish it and there were two US navy (SUPSHIPS) inspectors at our plant during all working times making sure we did it.

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Thanks for the quick reply. Very interesting anecdote to read as well, cheers!

I did what I should have in the first place and googled it after posting that message, and found sites which varied from one to the next in terms of how long they suggested before having to abrade, but all were less than the time I've left it.

Bah! More itchiness on the way then alas....

Whoever invented fibreglass needs a medal, and then a severe beating!

 

[Woodonglass]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

IF you rub your self down with Baby Powder and I mean really rub it in well, prior to grinding, and wear a long sleeve shirt and button up your collar etc. You'll find the itching goes WAY down. What kind of Resin are you using? As stated it's always better to apply succeeding layers as soon as possible. the 16 hour window IS a good one to follow. Basically if you finish laying up at 5 on one day you want to put the next layer of glass on sometime the next morning at the latest.

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Thanks for the info - interesting about the baby powder. Do you know why it is that this helps? I wonder if it just stops the dust from sticking to the skin or something?

A tip my friend gave me is to only wash with cold water after getting the dust on your skin since hot water opens up the pores in your skin and makes it much much worse. Kinda makes sense.

The resin I'm using for the current bits I'm fixing up is this stuff:
http://www.as-composites.co.uk/index.php?main_page=product_info&products_id=1627

It seems to be setting up very nicely. Really does feel good to know that when I look at these parts now they're rock solid without any give at all, compared to hanging loosely from a small flap of torn, badly applied CSM. The more time I work on it now, the more I want to because it's getting closer to having the job done. Probably sounds stupid but it's increasing the excitement again about being a boat owner.

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Ok, time for an update!

The parts that were trashed below the deck are now all repaired and stronger than ever by a LONG way!!!
The outer edge pieces of the framework that had broken loose or completely free were secured in place originally by a single layer of CSM.
They now have a few layers of CSM, roving, and choppies in the corners to strengthen them all, and are very solid indeed.

It's probably a bit of overkill to be honest but I'd rather have more than is needed than have it break up in future since I don't want to be doing this job again - it's been not much fun glassing these bits in such confined spaces I can tell you.

The boat has three points between transom and bow where these parts of the frame taper down to a triangular point, so 6 of them in total. The foremost pair were still stuck down just fine, so I decided while it might have been worth reinforcing them, that since they're ok now I would leave them alone and this avoids cutting panels out from the deck.
Now that the other 4 broken ones are extremely strong, there will be less flex, and this will reduce the odds of the front ones breaking in future. They're for rigidity rather than outright strength, so it's not absolutely critical but I feel a lot happier knowing 4 of the 6 that were broken are now better than new!

So the next step was to check the way that water drains once it gets below the deck (because one way or another, it will). I found that in the repaired areas now they were secure, water was able to pool and I didn't like the idea of this happening. It shouldn't matter but I'd rather have it all drain nicely to the bilge. Stupid design really that no-one thought to enable this in the first place.

I've added drainage holes where necessary, and in fairness it was only a few that were needed. The water now drains to the bilge easily no matter where it is applied beneath the deck. Result. The holes are modest size at about 32mm, and I've put a lot of water through the hull to wash out dust and tiny bits of debris, so hopefully there's nothing that will bung them at any point.

So the access holes cut in the deck need to be repaired now. The way I'm going to do this is to glass some pieces in around the edges of the cut areas which intrude into area, then replace the pieces that were removed. It's unlikely this would be strong enough alone of course so then on the top I'll feather in new glass to make a full strength join again.

Transom is being planned now. I've got 3 sheets of 12mm 8' by 4' marine ply ordered (the same thickness as the original transom was), so ideally I need to start making a big cardboard template for the panels.

What is the norm in terms of the joining of separate layers like this will be? Would they normally just have a layer of resin between the 3 layers? Or would it be best to have a thin layer of glass in between each ply panel? It seemed to have a very thin layer of glass between the ply layers originally, which makes sense as the transom void is 38mm and the combined ply thickness is 36mm.

I presume this helps the 'sandwich' effect that gives strength?

Progress has been slow but steady anyway, and when I can't work outside on the hull itself I'm trying to do things with ancillary bits like instruments etc so there's less to do once the hull is good again.

Another question I have is about a product called Chine Shine - it looks like good stuff for sprucing up the appearance of a dull hull. The hull isn't stained as such except for a bit below the waterline, but generally looks a bit faded and flat, and once the repairs are done I want to make it shiny and smooth again.

Enough waffling for now anyway, the rain has stopped so I can do something!

 

[Woodonglass]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Here in the states we just glue the plywood together with Titebond III wood glue. It's 100% waterproof and strong as heck. If you cant' get that where you are then Resin and CSM will do the trick Bonding the two transom pieces together. Have not heard of Chine Shine.

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Thanks for the info. A quick look on ebay shows I can get hold of the titebond 3 glue easily enough so that's not a problem if need be.

That said, I suppose if I use it, it creates a slight problem - it would mean the new transom panel would be about 2mm on the thin side against the original.

I'm entirely unimpressed with the build quality of the boat in other areas, but thinking about it now, I might need to do it by a layer of csm between each ply layer, in order to create the extra 2mm thickness of the transom, since that's how it originally was.

I certainly wouldn't be following what was done in the factory as a matter of course, since some construction stuff has been done badly, but in this case it might be the thing to do since I otherwise end up with a tiny gap either side of the ply.

Is it right that there would be a benefit in terms of strength to having the csm between ply layers? Would this for instance provide more resistance to torsion on the transom compared to ply alone? There must be a reason that the builders designed it this way originally and that's all I can think of in that respect.

This is chine shine:
http://www.deckhandmarine.co.uk/store/en/hull-cleaners/10-chine-shine.html

I've only heard good things about it so far (that's not just on the retailer's site!).


Something I need to think about with the transom I suppose is fitment of scuppers.
The deck is a self draining one, and originally just has two drain holes at the back, but no actual scupper valves at all. I know this is how it was designed and is no doubt safe enough but I don't like it, and want to fit scupper valves to limit what water gets in. I've absolutely zero knowledge or experience of these on any boats I've owned, and am not sure if it's something I need to get a certain type or do homework about.

Seems to be 3 styles of them commonly available, like these:
http://www.ebay.co.uk/itm/230712252...XX:IT&_trksid=p3984.m1436.l2649#ht_788wt_1270

these:
http://www.ebay.co.uk/itm/Black-Pla...ories_Gear&hash=item1c23041c1f#ht_2249wt_1270

or these:
http://www.ebay.co.uk/itm/Boat-2-7-...sories_Gear&hash=item53e7fd0e50#ht_500wt_1156

I have heard a few complaints about the 'ping pong ball' type ones that they don't always seal right etc, and i've not heard the same about the flap type ones, so I suppose I'd go for one shape or other of those. Be grateful if anyone has any tips on these things in general.

I intend to build a splash well also to help limit water ingress onto the deck, since the transom is much lower where the outboard sits.

 

[Woodonglass]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

I'm thinking that when you, lay the outer layers of CSM and 1708 glass you can get the finished thickness that you want. You will be applying a coat of resin to the wood then a coat of 1.5 oz CSM a layer of 1708 and if needed another layer of CSM and a final layer of 1708

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Yes that would do it, and additionally that outer layer will give a better mechanical bond I think for when I then do the tabbing afterwards.
Thanks

Cannot wait to get on with doing this!

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Ok - done a big clean up on the boat tonight. Removed the last of any mechanical or electrical stuff from the console, removed all the buouyancy tubs that were still out on the deck, removed all the crud, removed the wiring, then jetwashed the whole caboodle to clean it all up.

Looks tons better now and will be a lot easier to work on.

Also investigated the integral fuel tank and I have to say I'm baffled. The tank is too!
There's the residue from some old fuel in there - maybe a cupfull, so I need to clean that out along with some little cruddy bits and a screw that dropped in there. The inside walls of the tank itself are mint though as you can see in this pic:

What I don't understand is how the fuel got from tank to engine. There does not appear to be any outlet other than from the top of the tank, and this makes sense since the outlet from the top had a primer bulb and filter attached, and a few inches of hose that had been cut.
But the weird thing is there's a hinged seat that covers the top of the tank, and there's no way I can see for a fuel hose to not get squashed when the seat is down. So I'm unsure how the fuel line must have run from the outlet back to the engine. Any thoughts on this?

Here's the view from above the tank:

Right hand side hole is the filler hole, middle one is the fuel outlet (long metal tube down into tank, with primer bulb and filter on the top), and the left hand hole is for the fuel gauge sender.

Another question I have is that the sender looks in good nick, but the gauge for it was pretty messy. It's a VDO gauge.
Is it likely I'd be able to use any commonly available fuel gauge to replace the old one, or might I get weird readings because the sender isn't matched to the gauge or something?

Thanks guys.

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Anyone?

Anyway today I removed a couple of last fittings that I'd forgotten about, and had to drill out rusted old boats etc.
Fitted my tacho, trim gauge, and fuel gauge to the console.

Also finally test ran the good one of the two honda BF75's that I acquired some months ago in exchange for my lovely Yam F50.
Aside from a leak in the fuel line that caused air to be sucked in and bad running as a result, the engine ran great. Nice to know it seems to run well with all this effort I'm making elsewhere.

Got one side of the cap riveted back to the hull today too. Was not easy actually but I ran out of rivets so need to stock up to do the other side.

Also, there's a big teak (I think) board that the control box for the engine is bolted to, so I removed this, sanded it and stained it. Looks lovely now, but needs more coats, then some varnish.

The other job I did was to drill a few small drain holes in the big cable conduit that runs in the floor from the console to near the transom. In theory this is bad because of course with a sealed deck that has open scuppers/drains, it means water can now get onto the deck and through it to the hull! In practise, a few 8mm holes are not sufficient to allow any significant amount of water into the hull. There should not be much getting onto the deck anyway (especially once scupper flaps and splash well are added), so this is a non event. The bilge pump will easily cope with any trickle that finds it's way inside.

The reason for doing this is that without these drain holes, water fills up in this conduit where the control cables (electrical) are situated, meaning they'd be submerged a lot of the time, and I really think that's a bad idea for their longevity as there are joins in the cabling and no sealing will prevent eventual water ingress. This work will ensure they're always sitting in air instead of water, with the cost of a tiny potential volume of water getting into the bilge.

Marine ply is getting delivered tomorrow!

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Ok, so now I have a load of really nice plywood for the transom. Need some cardboard to make a template though first!

But on another note, I picked up some chine shine today when I found the local chandlery sold it. ?50 for 5 litres (so maybe $80-90 I guess) of cleaning product is bloody expensive by my standards, but the results speak for themselves I think. You just use a paint roller to roll this stuff on, leave it for 15 minutes, then rinse off with the hose:

I don't think I've ever used anything that works quite so well with such minimal effort, and am genuinely surprised at how well it works.
This will save me hours and hours of scrubbing once the boat is on it's side or upside down for the purpose of tidying up the underneath and filling all the chips and scrapes.

The surface after using this is remarkably smooth and shiny, so it really is impressive stuff. I'm assuming once it's rinsed off it actually burns through to the earth's core, because nothing that is this could can be environmentally friendly at a guess....

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Got a template for the transom boards measured and cut tonight from cardboard, and have now marked it out on the first sheet of ply.
Tomorrow night will hopefully get the first layer cut, and spend some time getting it as a really snug fit.

I've got about 12kg of polyester resin at the moment so as long as the ply is a good snug fit in the transom then I'd hope to not need anywhere near that much for bedding the new panel in, but I'd be grateful to hear feedback from others on the sort of amounts they've had to use, assuming the ply is more or less touching at all the edges, albeit not perfectly flush all round? That's if anyone is still reading this thread anyway.

Another question I've got is about suitable thickeners/fillers for polyester resin. How much thickener is likely to be needed for the sort of resin volumes I'm likely to need to use when bedding in the ply transom core? An idea would be useful so I can plan accordingly. I do have about 3kg of 6mm 'choppies' as well, and these are brilliant for a thick sort of buffer layer, so maybe that'd be more practical for creating a layer around the core, to help secure it and prevent air pockets etc.

Cabosil seems to have been mentioned a lot on threads I've read on here, but it doesn't seem to be that common a product in the UK and is quite costly for a small amount of thickener, so I wondered if there is a suitable but much cheaper alternative?

Many thanks!

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

This seems to be dying a bit of a death.
Never mind.

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Just received 2 big tubs of thickener so am good to go for this recore in terms of materials now.

Here's a few latest pics:

Last night I found that the new core is not thick enough yet at 36mm (from 3x 12mm ply layers). It's not a surprise since I know it still needs to be wrapped in fibreglass and sealed more before being dropped/bonded in. The original seemed to be around 38mm from what I could tell.

The thing that I'm dreading a bit is that once I've added thickness to the core by glassing it, that it's not then going to fit properly in the slot where it currently does fit, and that hours more sanding etc will then be required to facilitate a snug fit. I think that's what you call "tough s**t!" though!!

One thing I'm wary of is re-attaching the original outer skin to the new core.

Easy enough to bond it in place and I've no problem there, but knowing how to get it perfectly flush with the rest of the transom is going to be difficult! This is one thing that certain people have alluded to from the outset with warnings of an outside cut, and ultimately the cosmetics is a secondary concern to me, but having arrived at this point now, I may as well try to do it well if I can.

If I smooth the inside surface of this skin (still has loads of crud attached from when it was removed) so that it sits on the core and is perfectly flush with the remainder of the transom, it will then sit proud once bonded. This is an assumption admittedly, based on the thickness of any layer of resin/peanut butter beneath it causing it to push outwards somewhat.

The assumption here is that it would not necessarily be clamped again the new core with the maximum amount of force possible and as a result the bonding media will make a measurable (if small) extra thickness to the outer skin.

Or perhaps clamping as hard as I'm able to is exactly what is required? This is a question that I would appreciate experienced knowledge on, since it would be nice to get the outer skin flush fitted if at all possible.

If someone could advise on best technique for this I'd be most grateful, thanks!

On a completely different note, I managed to pick a set of BF90 carbs the other day for sensible money as an upgrade to the BF75 I have. It seems from everything the internet has to offer that the carbs are the only difference between BF75 and BF90 of this age, so it's a cheap upgrade that is a 'nice to have' (and still well within spec for the boat).

I've honda if they can confirm this is the case but I'm fairly sure it is. The block/bore & stroke/head/cam/cdi/coils/muffler/compression ratio etc are identical figures & part numbers between these lumps, and the only part numbers that are different so far when I've checked have been carbs and the stickers for the engine cover!

 

[CW180]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

Well, time for a little update. A lot of time & effort have gone into the boat over the last few weeks, and today, it finally got a new transom bonded in.
Still need to replace the outer skin but it feels rock solid, and was a perfect fit! Very pleased with the outcome.

Feels soooo good to have finally reached this stage now:

 

[Woodonglass]

Re: 1980s Coastworker 180 transom core replacement questions/advice sought

I'd say you did an excellent job!!! Using PB should allow you to get the piece of outer skin to align fairly well and your transom should be a BEAST. Overall, I am very impressed with your skills and abilities.