Search on spreader base . . .Quote:
Originally Posted by Westgate
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Search on spreader base . . .Quote:
Originally Posted by Westgate
I spent a few days at the boat this past w-end. I managed to get most of the decks sanded down to gel coat. I left the side decks since these are going to be tackled for a recore. Also started the icebox hatch removal...fun stuff! Started by cutting away the rim using a sawsall and my DA with 40 grit. I wish the paint would grind down as fast as that FRP did. Next I wedged a piece of mold release coated plywood up to the interior surface and then laid 4 layers of glass on top. While this was still pretty green I laid in a piece of "Core" (on a thin layer of thickened) which in this case was just a piece of 3/4" plywood. Prob should have waited for my new balsa core to show up from JD but I doubt this will ever see water so I wasn't too concerned about the material used. After that fully kicked I laid a heavy layer of thickened around both the perimeter of the old hatch as well as the plywood to seal things up (sorry no pic). I will grind this edge down to a nice taper before I lay down three layers of biaxal and do final fairing. I will also remove the ply from the interior and lay down (up?) a few layers of glass to really seal things up. I didn't get to this last stage because it was getting dark and "cold" after 6 PM on Sunday! I have attached a few pictures because everyone likes pictures.
Weather permitting I hope to finish the hatch work and start the recore this coming w-end. I have bad areas along both side decks between the forward berth windows and location of the winches. My windows were leaking before I replaced them last year so this was likely where the water came in. Even though there are some solid sounding areas along both sides I will prob just cut the whole side out and replace it. Then its done and it will be sealed and watertight and I will no longer have to worry about it. I will cut proud of the chainplates leaving the deck intact before digging out the core and filling with thickened (a la Tim Lackey). That way I don't have to be bothered with refitting the chain plate holes and they will never leak! Richard (PO/PO) replaced the foredeck back in 2004ish. It still looks very good. I have some dull sounding deck areas between the back of the forward hatch and the base of the mast. For some reason this troubles me more than the side deck job. I have read that this can be recored using just glass.
What is the collective wisdom about this approach over say a trad recore with balsa??
I also have some possible delaminations on the coachtop. I will investigate these with a drill before proceeding. I believe they are associated with where the bolts for the hand rails went thru the coachtop.
I will let you all know how things go. I know I am going to run into problems somewhere, that's just the way it is:confused:
Andrew
my 2 cents on the core goes like this:
If the Factory had minded their thru deck fastenings and holes the deck would more than likely still be a great shape after 45 years. All our rot was caused by rainwater entering all the nice holes Pearson provided.
Where I went into GOOD deck on A338 the balsa was married totally with the polyester and glass. It was not possible to separate the composite. It showed to me that Baltec (or whatever balsa core is available today) would be perfect with laminating epoxy. It might even be cheaper than pvc foam (Divinylcell) which is very expensive.
If your fastening holes are not sealed per textbook, balsa does 'wick' water - while pvc foam is closed cell.
That foam is marvelous stuff. It is non-friable - you can sand it down to a feather edge and it still holds together. Better than balsa core which is all endgrain. Epoxy sticks great to the foam. It could be useful for other projects besides deckcore.
For instance A338 is going to have an epoxy frp and pvc foam core rudder.
Under water, don't use balsa.
If you can afford the closed cell foam, go with that.
But the balsa (available from Defender) is pretty neat stuff too.
You'll be encapsulating, so it will be perfectly protected for another couple generations!
Have a feeling that the balsa will suck up more epoxy than the closed cell foam will, A consideration given how shocking all this fancy material costs these days.
The price of epoxy is quite a bit. I would guess that using any core material instead of solid glass would save alot of money. I have very little core in my new decks. I am at 7gallons right now. And I will need three more to finish. All of a sudden the balsa looks pretty cheap.
It's off to the boat I go!
This w-end wasn't what I would call productive. Between the rain, wind and cooler temps it was hard to get much done.
Anyway I did manage to take advantage of a warm spell on Sat to lay some fibreglass into the ice hatch. I used 1708 biaxal. I really like working with that stuff. Lays down nice but it does soak up alot of the juice. Anyway the basic box has 3 layers of biax and thena few more on the port side to bring up the level a bit. I also put a layer on the underside. I will prob put one more in there and call it quits (except for fairing).
I was forced inside for pretty much the rest of the time there. I sanded the forward anchor locker in prep fo rpainting w bilgecoat. Later I put down two coats. Nice paint covers well and goes on pretty easily. Next I focused on the strongback. It was really on eyesore. I supported the SB with a 2x4 and then removed the metal reinforcement plate. I then trimmed up the glass with the dremel making a nice clean edge. The glass had been just torn out to install the metal reinforcement plate. Next I sanded down the SB and its supports. This I did not only to rid myself of the paint but to enable me to have a good look at the SB itself to determine if replacement was necessary. Much to my surprise everything looked good. One issue....looks like Pearson's boys filled (well not actually filled!) the gaps between the SB and the supports on both sides with bondo after cutting both suports short. Maybe this was done for a reason but if so it was not apparant to me?? Anyway I will either dig out the bondo and re-glue with thickened or replace the supports with new oak timbers. The SB itself looks in good shape. I will replace the metal support once everything is cleaned and varished.
Spent a bit of time grinding but it was half hearted. I decided not to start the recore but wait for a better forecast.
Here are a few pictures to sweeten the deal!
Andrew
Here are some pics of the SB assembly. Not finished with the sanding but got the majority of the old paint off. Very happy that it looks a bit more shippy..well on its way to looking more shippy. The oak actually looks much nicer than the photos show.
Now I have to do something about the rest of the forepeak:eek:
Andrew
Andrew,
SB looks well fitted and plenty strong!
You put a fair curve back into the roof...fantastic.
Dunno 1708bixal but it looks and sounds (thirsty) like x-mat.
Indeed, great fabric in many ways.
You obviously have fun with the stuff!!!
Thanks Ebb!
Given your level of expertise with these matters why do you think they did not fit those supports better? Friday afternoon, too much wine with lunch?? Do you think that I should take care to flush those supports up. If so what would be the recommendation?
Andrew
Andrew,
I still think that after 45 years the Support structure in Ariels just shrunk.
And I would think that since no glue was used by Pearson on the plywood bulkhead, only screws were used, you know, the bracing and all just settled over time. Naturally the mast being pulled into the cabin by the rigging helped some.
Some thought should be put onto where the StrongBack forces are ending up in that part of the boat. If we were going to design this compression beam from scratch we would probably put a wide band of built-up material all around the edge of the bulkhead against the hull - across the top AND across the bilge. Totally spread the load. Whether we can do this is another thing.
The major beam support cross braces in 338 were terminated onto the V-berth lid. There was no extra bracing or cleats or whatever, except for some frp tabbing of the lid to the bulkhead (and the hull).
Of course the V-berth box structure does somewhat 'spread the load' of the mast compression to the hull. But the Pearson braces can easily deflect the V-berth tops. imco
Modern fiberglass boats are going to end up with prominent hard spots, or vertical ridges from any bulkhead if it bears on the hull with a huge load on it.
Ariels have thicker hulls generally and the overall tabbing of some interior ply structures have locked in support. I didn't notice this vertical inside bulkhead ridge phenomena on 338. Actually there were prominent horizontal hard spots along the hull made by the stringers that distracted my attention.
But we can visually check out where the downward force of the mast ends up inside the boat. Mental arrows.
That's why I added extra plywood on the inside of the V-berth glued to the existing bulkhead. Adding a large cleat. Got in there by jigsawing the top off. I believe this provides direct support for the struts holding the beam up that are terminated on top of the berths. I put on extra tabbing over extra wide fillets. Overbuilt everything in true amateur fashion. But I'm sure the hull shares the load now.
Also added a piece fitted into the bilge and across the step - a natural place because this is the step up into the forward stateroom. I think of it as closing the circle. Maybe it's Druid, or mystical?
Practical?.....no.
I believe everything under the mast should be immobilized and that the whole structure, ply and braces across the roof and in the bilge should be one piece as much as possible.
Thinking wasn't clear in the beginning. I added on. A little here, a little there. I really think now that the whole Pearson bulkhead thingy should have been pulled out in the beginning and a whole mo' better constructed support system put in from scratch. Next time.
Well, we have what we have. It looks like you've got it covered pretty good. Especially if you are epoxy gluing everything together.
Fiberglass boats are monoques - their strength comes from their skin rather than interior framing like wood boats. lobster vs salmon.
I feel any interior framing on my part should be part of this concept. Web frames and attachment points all seamlessly going from one to the other. Interconnected comparments, yea, liketh the inside of the mighty lobster.
The Support Beam is an exception because the mast is a point load. The beam is actually guaranteeing that the cabin roof keeps its arch.
[If the crustacean image is apt, it's funny that the Alberg/swede word for lobster is HUMMER!]
Epoxy and glass, with a little white oak thrown in, makes it, as you show, not a problem and fun to do.:rolleyes:
Thanks for the thoughts Ebb! I like your exo/endo skeletal comparison. As long as our boats don't ever develop a hydrostatic skeleton :eek: we should all be fine (Bio-geek talk!).
I may dig around a bit and see if there are any easy to access points below that I could reinforce. My plan is NOT to rip out the bunk so we will have to see what presents itself.
I'll be sure to keep posting!
Andrew
I notice your bulkworks doesn't have the angled oak beams, Have they been removed? Or is it possible your vessel didn't have them. Installing them would give added support
Yes I have noticed this too. There is no indications that they were ever there (scars, old screw or nail holes sloppy bondo). Arthur is 387 in the run. Do other boats around this have them?
Andrew
A-414 does not have them either.
PS. Looking good Andrew!
I didn't see any scar damage in your photos either.:eek: A-259 has them.
Carl
Just to be clearer - but maybe not apropos:
A338 did have those diagonals, which of course made textbook immovable triangular bracing.
Those white oak braces terminated on the v'berth, and imco the as-built v'berth provided little if any support, being 1/2" plywood with a little cleat under it. You know, they made great effort to immobilize the compression beam but the system was not grounded.
Ultimately the support beam is/was held up by the doorway posts alone.
Those posts terminate on the hull. But they are screwed to the plywood bulkhead. I would say that all together nothing moves that much in this original Pearson setup. But as we know over time it did move.
Might take a worklight to the boat outside if still in the jacks and shine it low angle along the hull where this bulkhead is and see if you have any bumps photographing through. Can also lay a long horizontal batten where you think the bulkhead is to see if there are apparent hollows on either side.
imco we have to think of the mast as a dynamic load on the interior support structure. It's always working, moving, changing, loads could get extreme on certain points of sail. That's why I think it's wise to look at where this load ends up inside the hull. That's all.....