1740

stringer slots cut and test fitting of the stringers done <img src="<>/cool.gif" alt="cool" title="cool" height="15" width="15" />

So while I'm

in there

..... I found a couple of uglies, previous repairs that had long since past their use-by date, so these have been re-done and are now all good.

this is the worst one I encountered....

starboard side of the port hull at the transom.

cleaned up and ready for glassing <img src="<>/grin.gif" alt="grin" title="grin" height="15" width="15" />

if you look closely...... you'll notice a

mark

on the starboard hull, just behind the beam mount...

interesting as it sort of seems about the same age as the damaged section of the port hull but far less severe...

closer shot of the damage ....

me thinks another cat may have been the cause of these two strikes
<img src="<>/smirk.gif" alt="smirk" title="smirk" height="15" width="15" />

regardless of when / where / or whatever, these two impacts have been re-repaired and the hulls are now in a clean tidy condition.....

With the hull repairs all finished I can get back to the deck rebuild.
I added ply plates to the port hull so it matched the starboard hulls design, these were fiddly to do as I didn't remove the stringers from that hull.... Matt had rebuilt this side a few years back and the setup was still reasonably sound, no point in making work for myself, although it probably would have been quicker to rip them out in hind sight.

in this shot you'll notice a couple of major changes.....

1/
the fore decks have been removed <img src="<>/shocked.gif" alt="shocked" title="shocked" height="15" width="15" />

2/
the port hull's centreboard case stiffener has been removed <img src="<>/shocked.gif" alt="shocked" title="shocked" height="15" width="15" />

Item 2....
I wasn't happy with the height of the centreboard case stiffener, it had put a bulge in the deck and subsequently fine cracks had appeared at both the front and rear of the actual case slot.
My deck shape template showed that the case was sitting about 6mm too high, obviously this placed a major strain on the deck in that area.

Item 1
I had a

rattle

in the hull and no matter what I did I couldn't shake what ever it was free nor could I get it to move down enough to be able to physically remove it ....
the deck simply had to come off

and the culprit was......

any wonder I couldn't shake it out <img src="<>/crazy.gif" alt="crazy" title="crazy" height="15" width="15" />

the 3rd reason I removed the foredecks was for the front shroud mounts, both of these had movement, granted it wasn't a huge amount but they should be solid, the starboard hull mount was slightly worse with a distinct click each time it was nudged, The actual fixing is good but the bolts had simply come loose.
They also have a small washer on the nut side and this really isn't big enough to spread the load evenly through the timber sub-frame. A larger plate will replace 2 of the washers and the 3rd bolt will have to do as it is, its simply in-accessible.

foot note:
The front stay mounts have 3 holes for mounting, Being in the fabrication/engineering game I hate this type of connection, odd numbered connections simply don't work as well as even numbered connections, reason being one of the bolts will ALWAYS act as a hinge or lever point on the other bolts....

just sayin
<img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

So where am I up to at the moment.......

all the repairs have been done, and the work on the deck strengthening is completed, and I've made a few minor mods to other sections such as adding 2 stringers to both hulls from the transom plate to the rear beam (one had been damaged purely from being leaned on so they were obviously a tad weak).

I've spent endless hours scraping / chipping excess resin from all over the hulls..... 5 vacuum cleaner bags full to be precise plus a good sized amount of chippings that the vacuum simply couldn't take due to the size <img src="<>/shocked.gif" alt="shocked" title="shocked" height="15" width="15" />
All up.... ~6kgs of

rubbish

has been stripped from both hulls. I have added ~1kg of additional material with my design changes / strengthening.

gotta be happy .... a fitness program where the boat gains a major strength upgrade and yet looses more fat than was added
<img src="<>/grin.gif" alt="grin" title="grin" height="15" width="15" />

Plans for this weekends work, fit new fore decks and rear decks.
<img src="<>/cool.gif" alt="cool" title="cool" height="15" width="15" />

couple of quick ones.....

the new stringers I've fitted to the rear deck area, should also help with the hatch which was just bolted to the ply deck
<img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

closer shot of the centre case stiffeners, this was ~20mins after being glued in

that troublesome front forestay mount that's loose
mutter mutter mutter ......

you can just make out the gap between the resin and the plate which is due to the plate movement.

the other side view......
note the washers that are fitted, any wonder there's movement.

As you can see I'll have to

dig

the top bolt from its grave of resin in order to fix it properly.....
more hours of time on the fiddly stuff
<img src="<>/frown.gif" alt="frown" title="frown" height="15" width="15" />
& naturally.... guess which side I need access to.... yeah that would be the one where I'll need a child sized mit

mutter mutter mutter
<img src="<>/mad.gif" alt="mad" title="mad" height="15" width="15" />

Nice work. Interesting what you say about odd numbered securing on fittings. My diamond wires are attached with 3 rivets after I drilled out an additional hole, but they are more in shear but I never considered the lever action. Fantastic work on the hulls.
I just helped a friend buy a wooden mozzie but is good to see one back to a skeleton.

I work in steel fabrication, so design through to completed work is my pay packet <img src="<>/smile.gif" alt="smile" title="smile" height="15" width="15" />
Everything we manufacture from major steel work to a 'kit shed' all relies on even numbered bolted connections, yeah even those kit sheds that are tek-screwed together use even numbered screwed joints.
There are other factors that come into the equasion such as clamping area and rotational forces but in 99.9% of designs we have to have engineered are all even numbered bolted joints, I cant actually recall ever using an odd numbered connection
<img src="<>/crazy.gif" alt="crazy" title="crazy" height="15" width="15" />

With my front shroud plate, the lowest bolt in the pic has become the 'hinge point', this places a leverage load on the two other bolts.....
Obviously they wont sheer but they will add undue pressure to the weakest part of the connection which in this case is the timber sub-frame, and hence the movement I now have, this movement is

wearing

at the timber holes.....
My plan is to enlarge the clamping area over what it currently is, and by fitting a plate to the nuts side of the timber sub-frame I should dramatically increase the 'grip' the fitting has... this plate will be the same size and shape as the actual fitting
(thankfully there's a good supply of stainless sheet in my shed, this is one of a few fittings that will be re-worked... stay tuned)
<img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

well it took all afternoon but was worth it.....

NB: Washers are under the actual bolt heads now

and the other side......

My new plate glued into place and all nice n tight
<img src="<>/smile.gif" alt="smile" title="smile" height="15" width="15" />

maybe tomorrow I might start to get some decking action.....
<img src="<>/mad.gif" alt="mad" title="mad" height="15" width="15" />

The rear decks are done.... pics to follow <img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

but I noticed something wasn't quite right with the fore decks, so after a bit of investigation......

the deck had dropped down considerably, ~5mm drop between the front beam mount and the forward shroud mounting plate.

Around 30% of the stringer/sub-foam connections had let go so the stringers were basically

floating

other than the connection to the deck.

So I went for a similar plate to do the load bearing for the stringers and to take that load into the sub-foams, the stringers that hadn't let go were cut with a hacksaw blade cut at ~45degrees as seen.
I cut some junky old 12mm ply strips up into the shape of the deck and then zip-tied the stringers to the strips so that they were held in the correct place while the glue set on the new support plates.
Once the glue on the plates has set I'll run a strip of 50mm wide 100gsm cloth across the visible face and onto the hulls so it ties it all together
<img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

I only fitted 3 small stringer supports to each hull as the support at either end is good so it just needed a bit of help in the middle......

Today I'll build up the compressed foam and reshape it to the correct deck profile instead of the banana shape I had, and maybe tomorrow if the family decided that the world isn't about to end....... I might get the foredecks on

must be doing something right.... 1103 views and no-one has told me I'm doing it all wrong

Hi Allister, I can't find your number on my phone, but I'm guessing you've sourced the plywood for your decks.

Just wondered,I need to order some more, but if I'll order a sheet less if your right.

Matt.

for the fore deck and rear deck...... yup <img src="<>/smile.gif" alt="smile" title="smile" height="15" width="15" />

for the main deck..... you better order 1 sheet for me please <img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

txt sent with my number

<img src="<>/cool.gif" alt="cool" title="cool" height="15" width="15" />

rear deck fitted and ready for hatch hole

starboard hull just after foredeck fitting was finished

port hull

the junky old ply was used to press the deck down and hold it on place while I stapled the deck down.
Once its cured I'll cut the excess away and then smooth it into a neat finish......

main decks next w/end ?????? <img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

foredeck and rear decks are from 3mm thick 3ply, the main deck will be 4mm thick 3 ply.
Originally it was all 4mm thick ply over the entire deck area, so the weight of the added plates I've put in is offset by the lighter timber fore and aft decks..... admittedly it isn't a huge saving but it ended up being so close to equal its not worth the argument over the vast strength gain I've achived.

The goal right from the start was to get structural strength back into the boat AND get the weight down to the minimum as best as I can .....
<img src="<>/grin.gif" alt="grin" title="grin" height="15" width="15" />

Still following this forum with interest. Where did you purchase the 3mm ply? We cannot get any in Adelaide.

PM sent....

When I first thought of purchasing Jurassic Karp I did some research of timber availability ..... mainly the differing types of ply and their abilities.
Marine ply, water resistant ply, normal ply, etc etc all supposedly have very different properties, asking a few questions tho came up with very different answers and prices aswell <img src="<>/shocked.gif" alt="shocked" title="shocked" height="15" width="15" />
Eventually I discovered there are some differences in the glues used although not a great deal, more a case of how

watered down

the glue is to its use...... the other main factor was the quality of the timber veneers but the biggest difference came with the actual process of manufacturing, lower grades of ply are just about chucked together leaving gaps and in some cases overlays of the veneers, 'better grades' appear to be laid with more care with only the odd gap between the sheet, we've all seen small gaps in a middle layer mostly they are 1~2mm wide...... the high quality or what we call

marine grade

is basically precision laid quality veneers with no gaps or overlays and a un-watered down glue..... which obviously COSTS !!!!

After talking to 2

old salts

(both boat builders from yesteryear) they both suggested I use the

water resistant

ply as its quality was

good enough

, as it turned out one guy had a sheets left over from his last A-Class build, this was purchased for $25 <img src="<>/grin.gif" alt="grin" title="grin" height="15" width="15" />
I took the sheet to our local cabinet maker for his opinion ( and to be ripped down to size) and he told me that this paticular ply was still available commercially should I need more of it, I did purchase a 2nd sheet as the original sheet had marks that may have caused issues later on... I can supply his details if you want to discuss it further
I can not pick any difference between the old ply and new ply that I have other than the dust that's been rubbed in slightly, the pliability or 'bending' is ever so slightly better in the newer sheet, as a result I used the older sheet for the structural work and the newer sheet went into the curved decks.
<img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

The best quality okoume (Gaboon) plywood available as far as I'm concerned is from Andrew Denman Marine in Tasmania. I have several sheets here, with one going to Pirate, and will be ordering more in the next month or so. Look them up on the net.

When Pirate picks up his sheet, I'm sure there will be a very good review of this plywood. Andrew Denman will ship to the mainland, would have to contact him for freight costs to South Australia, but my last order was actually shipped free to the mainland, I had to pick up from Melbourne.

These sheets are not only excellent quality, but are also 2500mm long sheets, which as you may be aware, results in only 1 scarf being needed for Mozzies and other classes.

I have no affiliation at all with Andrew Denman Marine, but I've had marine plywood from all states on the east coast, and this stuff is the best I've seen and worked with, and its information worth sharing.

http://www.denmanmarine.com.au/

<img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

Yeah I know.......
you've been missing ya daily dose of what's Kingy up to now ? <img src="<>/smirk.gif" alt="smirk" title="smirk" height="15" width="15" />

well not much ......
pulling staples out of the foredecks
and
fitting the main decks.....

Made a couple of minor changes before I fitted the mains, simple stuff really, tig welded nuts to plates and urthaned the plates in place .... eliminates me having to reach through the hull to do up bolts
<img src="<>/grin.gif" alt="grin" title="grin" height="15" width="15" />

All staples are now removed from the foredecks and they have been shapped to the hull and fully sanded.
should be able to start pulling the staples from the mains this w/end ..... mutter mutter mutter ... more bloody staples !!! <img src="<>/mad.gif" alt="mad" title="mad" height="15" width="15" />

NB:
sorry for the pic quality..... dusty shed and Iphone lense <img src="<>/blush.gif" alt="blush" title="blush" height="15" width="15" />

I've had a couple of messages about the tools I've been using, probably more along the lines of what

specialist tools

did I buy.....

Seeing the only 'wood working' tools I owned prior to this rebuild consisted of an axe, sledge hammer & wedges, 2 pro chainsaws and a 70ton log splitter.... none of which are really suitable for 3ply wood
<img src="<>/cry.gif" alt="cry" title="cry" height="15" width="15" />

so here's my list ......
10

GMC bandsaw which cost me $40 & another $39-95 for a new blade ..... mutter mutter mutter

near new 12

tenon saw, cost me $10 at a yard sale
(included a couple of horse rasps aswell)

Number 4 Stanley plane, freebie from #1 son (chippy)

renovator.... borrowed but would be well worth buying ....

staple gun..... had it for years and cant recall the price.

a jigsaw.... had it but its never had a wood blade so $5 for 2 blades at the local hardware store

I've also added an electric plane & a belt sander, neither have seen much use at all so they were a bit of a waste of money.

for the resin side:

plastic cups for mixing in, supermarket, 10 for $1-95

stirring sticks ..... off cuts of ply so freebies

2

paint brushes came from the local two dollar shop, 3 brushes for $2

syringes.... may seem a tad odd but they worked perfectly for injecting resin into tight spots without spilling it everywhere, I also used them for running a bead of resin along the stringers when fitting the decks.
these came from the local Vet and he didn't charge me a cent, he also threw in a couple of 18guage

horse needles

which I used for pricking any air-bubbles I got, not that I got many and I only used 1 needle for this.

I didn't go for the special grooved rollers, I did however use a squeegee made from a piece of 6mm thick plastic, roughly 5

X3" on size and I ran the plane along both edges to get a nice smoooooth vee'd edge, this was an excellent tool for spreading the resin over the ply and then laying the glass cloth into it.....
cost me zip as I cut it out of the side of an old wheelie bin
<img src="<>/grin.gif" alt="grin" title="grin" height="15" width="15" />
ok.... so I'm a tightass.... but what I save means I can spend elsewhere
<img src="<>/cool.gif" alt="cool" title="cool" height="15" width="15" />

the only other thing I've got....... is a massive learning curve, its been a challenge but I've enjoyed every moment so far

watch this space
<img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

Not much of a handy man these days myself, so haven't had much to say, but love watching other people work <img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />.

Probably a bit late now, but am wondering if the technique used for holding fibreglass sheathing in place before applying the resin on large jobs might help. It's held in place with staples gunned through packing strap, then you pull the packing strap up to pull out the staples, some need pulling with pliers still, but some come out clean. Thinking about it probably only works if staples are at the right angle to the packing strap. <img src="<>/confused.gif" alt="confused" title="confused" height="15" width="15" />

Just for the record. That's my trailer ^^ and it works a treat!

Glad to hear that, the old fella said it was great to use aswell.

That marvellous thing called 'hind sight', said I should have run hay-band under each staple, would have made the process much easier and quicker too
a 'zig-zag' pattern with the hay-band would have let me run the staples in a nice straight lines as I did

The removal process was slow to start off but once I had a method then the speed came shortly after, a razor sharp chisel and a pair of wire side cutters got the job done relatively quickly. The chisel was just good enough to pry one end of the staple up slightly and then the side cutters did the rest.... I did one main deck in half the time it took the first foredeck.

Laying the cloth was an easy process, pour the resin onto the ply, smear it around with my wheelie bin squeegee into an even layer, lay the cloth down and then work it into the resin coated ply with that magic squeegee

<img src="<>/wink.gif" alt="wink" title="wink" height="15" width="15" />

Todays task (aside from the family stuff) was to get one hulls deck finished....
excess cut away,
smooth the ply's edge to the hull,
trim the excess away in the front & rear beam slots,
cut the hatch hole,
cut the centreboard slot,
radius the edges of the new decks,
sand the entire deck down,

completed..... now for a reward ..... where's me rum ???