F85SR Concept Boat

I undercoated the floats a couple weeks back.
I add some pics below.

Undercoated Floats

Carbon Fibre Chainplate still needs some attention.

Flush Hatch.

I've sprayed a duster coat over the floats and beams.
Sanding this off will help identify any areas that need further attention prior to top coating.

Not much happening on the boat building front lately as I've been taking care of a few other projects. One of these was converting a rusty old mangle into an etching press. I finished that last week and I am now setting up the frames to start the main hull.

Currently foam planking the first side of the main hull.
It seems 300mm wide strips will do the job. Note I have gone overboard with both battens and screws. My reasoning is that it is much more pleasant carefully screwing on the foam as opposed to filling and sanding. I went this way with the floats and there was very little fairing needed to get a nice straight and fair set of hulls.

The planking is almost done for the port side of the main hull.
Its getting a bit tricky at the bow because the foam won't take the tight curve even after being heated in the oven.
I'll try kerfing the foam in this very tight curve and see how that goes.

I'm laminating just the hull first because leaving the battens for the cabin side and deck off gives better access and keeps the hull surface within reach for the laminating.
The cabin side and deck will be done before moving onto the stbd side.

The kefring worked great. I only had to kerf the keel from the bow back 1200mm.
This gave a very smooth curve. I'm currently busy preparing the foam to take a vacuum for the laminate. I'll post some pics when I get a chance.

I finished laminating the inside of the port side of the main hull today.
Yesterday we laminated transom to frame 9 and today we completed the job up to the bow. In each operation I managed to apply the vacuum well inside the vacuum window specified for the resin and achieve a vacuum of 22 to 25 inches of mercury. This is around the same as the floats and if this continues it should make a pretty good boat.
I'll post some more pics soon.

The kerfing worked as a means of forming the tight curve near the bow.
I used a 4mm circular saw blade to cut 5mm deep slots in the 10mm foam/.
As a precaution I still heated the foam in the oven before shaping.
This is much easier than than correcting a bad shape later.

Just a couple pics of the port side of the main hull.
Note I've not yet installed the battens for the cabin side or deck battens.
Leaving them off until the hull has been laminated allows much easier access.
I'll now go ahead and do the same for the cabin side and deck.

The vacuum bag etc has been removed but the peel ply will stay and just remove
sections as needed as leaving it in place keeps the laminate clean avoiding possible
contamination of area that I may need to bond bulkheads to.

Hi Phill,

whouw great progress and very good work as always.

I like your flush hatches. Would you explain how you made the invisible parts to get them watertight? Are there any drainage channels?

Best Regards, Michel

Michel,
The parts to make them watertight will not be installed until after the floats and beams are joined. Only because it will be easier to do the glassing of the fwd beam to the bulkhead without them being in place.
They are nothing fancy just straight out of the plans.
They are not complete yet but I'll try to remember to take a pic of where they are at and post it so you can see. I will be drilling drainage holes so any water that get past the hatch seal will be caught in a channel and leave via the drainage holes.

Regards,
Phill

Hi Phill,

thanks for this! I have a slight idea how this will work, nut would like to see some pictures. If you allow I will remember you so you don't have to think about it any more and can concentrate on your project.

Many thanks and best regards, Michel

Michel,
Thanks for the reminder.
The pic is of the partially made fitting that will eventually go inside the hatch. The insert sitting on top is made from 2 layers of 5mm corecell foam with a rebate to ensure it is located at exact height in final fitting. It still needs to be sanded and top shaped to match the underside of the hatchand looks pretty poor at this stage but will look right when finished.
Once this is done it needs glassing and this will be done in two steps. Glass the outside while it is in place in the lower fitting with packing tape being used to afford a release so I can make a flange for later glueing together. Then glass the inside. A neoprene seal will be fitted to the top edge.
Keeping it in two parts until fitting beacuse this allows me to tape the lower fitting in place before adding the insert. This is the only way to get access where the flat section meets the hull. Prior to adding the insert would also be the best time to drill the drainage holes.
Any water that comes in the hatch will go into the channel formed by the fitting and exit via drainage holes.

I've laminated the cabin side using 16mm foam so it was thick enough to rebate the windows later. Having the windows fitting near flush would look so much better than them sitting proud of the side.

I've also continued on with the 16mm foam for the cabin top.
The pics show the foam in place. I hope to get to laminating it in the next day or so as I'm looking forward to fitting bulkheads. I may take some time out to further upgrade my vacuum table for the laminating of the bulkheads. It works well but an upgrade should give me a better duty cycle of the vac pump on/off.

Today I laminated the cabin roof and foredeck of the port half of the hull.
I weighed the glass beforehand @ 1775gm and the carbon uni used @ 100gm. So you would expect to use around 1900gm of resin. I managed to wet out the laminate with around 1900gm of resin but by the tine I'd properly wet out the peel ply I had used 2500gms of resin. However the peel ply tends to show any dry areas in the laminate beneath and correction requires more resin. The vacuum and absorption fabric help to correct any areas where there is excess resin.
IT is currently under a vacuum of 25 inches of mercury and with the vacuum pump only coming on for 20 secs every 30mins to maintain the vacuum, leaving the pump on overnight is not a problem.

I pulled all the vacuum consumeables off yesterday and the laminate looks great. Towards the end of the week I should
have a few domestic chores out of the way and be working on the bulkheadS.

It was rather interesting the fun I had laminating the underside of the cabin roof.Leaving the peel ply keeps the laminate clean and there for easy to bond to for the installation of bulkheads etc but the surface is just a little slippery. When setting up to laminate the roof I had to get inside the hull and up near the bow kept sliding into the surface I wanted to laminate. I set up a series of ropes to help avoid this.

Well I just pulled the second half of the companion way bulkhead off the vac table.

That was the last Bulkhead that I needed to make.
BTW:-Looks a bit out of proportion because I make them slightly oversize and use the CNC cut template and a router to trim them to the exact size once laminated.

Now I have to make the **** seat and floor but the vac table is not quite big enough.
Next week I'll drop into the local hardware store for an oversize sheet of MDF. and rig something up temporarily for these.

I'm currently fitting the bulkheads into the port half of the man hull while in the mould.
I'm taking my time and checking they are exactly right.
The other half B/H in the other half of the main hull will have to line up.
Note b/hs are screwed to timber bracing to make sure they don't move while being filleted and glassed in place.
Peel ply still on B/hs and just enough removed from the hull to bed the b/hs in epoxy bog.
Once cured enough peel ply will be removed to fillet and glass in place.

When I built my first boat back in the 80s my attempt to
fillet and glass in the bulkheads was woeful. I took a
piece of 4mm ply and shaped the end of it and then commenced
to try and coax the filleting compound into the joint.
Of course I ended up with a right mess.
I read how it is wise to tape either side of the fillet so you
can remove the tape and the mess prior to glassing.
The other problem that I had was the filleting compound would
squash out of shape.One could wait until cured but that would mean
sanding the fillet to get it smooth enough to take the glass tape
with no air gaps between the two.

These days a very simple and effective method has evolved.

If using 100mm tape I coat 50mm either side of the joint to be
filleted and glassed with resin mixed with slow hardener.

Then I make up the filleting compound with resin with fast hardener.

I deposit the filleting compound in blobs along the joint and run
a bit of rubber 4mm thick and 2.5 inches by 2.5inches with a rounded
corner. The round on the corner is the shape of the fillet that I want.
This rubber tool distributes the compound into the joint and cleans up
the work in the one operation. I then wet out the glass tape on a separate
board and use it to glass the joint.I also apply peel ply an inch or so wider
than the glass used. If doing a few joints by the time I get to glassing
the first one the filleting compound has gelled enough to hold its shape
but still soft enough to take the glass.
Below is a pick of a joint done this way.
The joint is very smooth if you run your hand along it and
very little effort required to fair the edge of the glass tape as the peel ply has done most of the fairing already .
It's a pity my photographic skills didn't also improve along the way.

Yeah your right your photographic skills suck! 😛 Seriously these fillets are absolutely perfect (better than my cornices!) and I think this is the first boat I've seen where I would have no issue running my hand inside hidden recesses with zero fear of getting snagged on a sharp glass needle.
Keep up the good work...just work faster <img src="<>/smile.gif" alt="smile" title="smile" height="15" width="15" />

Mark,
I understand your comments about the cornices. But then I hate putting them up so not surprised they are not perfect.
Building boats on the other hand I really enjoy.

Recently I have been making the flat panels for the * floor and * seat.
I seems like it is taking up a lot of resin and concerned the panels may be heavier than optimal because of this.

Once again I took detailed notes when making the panels and decided to analyse the outcome of the * seat panel.

The * seat all laminated but with peel ply still on weighs 5800gms.

It was made in two sections and joined after because my vacuum table is not long enough to do it in one piece.
It took 120grams of resin to glue them together and glass tape the join with 60gms of glass tape..
Not concerned about this weight as the joined section will be cut out and discarded
when the CMM is fitted but the numbers are needed in the analysis.

So 180gms all up to join to two halves.

Making the panels the glass required to laminate the upper surface 896gms and lower surface 614gms.
Total 1510gms. And I used 2051gms of resin.
The foam weighed a total of 2328gms.

With the finish panel weighing 5.8kg but still covered in resin soaked peel ply.

I weighed a section of peel ply that I removed to do the join and this allowed me to calculate that there is still
approx 318gm to come off the 5800 when the peel ply is removed. leaving 5482gms for the panel.
When you subtract 180gms (joining) 2328gms (foam) and
1510 gms (glass)

So 5482-180(join)-2328(foam)-1368(glass) = 1464 of resin in the laminate to wet out 1510gms of cloth and fill the 1.5mm holes drilled every 30mm.
The laminate on close inspection looks perfect so my concern about resin consumption resulting in a heavier than optimum panel is not something to worry about.

My resin allergy has been causing me some problems so I thought I'd take a break from working on the boat for a couple of days and analysed some weights to pass the
time and cross check what I'm doing.

Crazy waste of time?

Most certainly!

But I found it entertaining.

BTW:- below is a couple of pics of how I have approached the installation of the * floor.
The extra timbers are set up to align the * floor exactly and will be removed before I can install the * seat.

Under the floor.

Thanks for the Pics Phill. Great to see your progress. I hope you can contain the allergy problems.

regards
Nico

PS: I have a few weeks off later this month, so I hope to put some valuable building time in.

Phil,

a boatbuilder I used to do a lot of work with in NZ had resin

sensitivity issues

, he found that if he changed brands with every project that it minimised the issue. If you're still after some help with your mast I should have some time at the end of the week to look at it.

Chris,
Sounds like very good advice.
I have used 4 or 5 diff makes of resin over the years and find they seem to affect me in two different ways depending on the ratio of hardener required.
5:1 cause me to blister where ever they contact my skin.
The 2:1/3:1 resins affect my breathing and airways.

With this project I'm using one brand of resin for the building and a two different brands for the fairing.
One for the rougher fairing and one for superfinefairing.

Your friend makes a good point but I think I've exhausted most of my options.
Now I have to be very careful to limit my exposure and I take a break as well as anti - histamines to help when exposed.

I would certainly appreciate help with the mast if you can spare the time.

Thanks,
Phill

I have now finished installing both the floor and * seat.

Using some pulleys attached to the **** floor and going to an over head beam
I managed to break the hull free of the mould while some friends threaded a webbing strap between the hull and mould battens.

I bought a couple trailer winches off ebay and made up some steelwork
that will allow me to clip them on the 1 ft deep RSJs running down each side of the hull.
This should allowme to pick the hull up and rotate it to work on at any angle right up until it's time to join the foats on.

I pulled the mould apart last night and today a couple friends came around to help roll the hull over. I asked them around just in case the winching system didn't work as expected.
Turns out everything went off smoothly.
One of us wound webbing out of one winch while the other wound the opposite winch in. The hull rolled over and then we just wound both winches out so the hull could settle down on the supports that it will sit on until the outside is glassed.

I am thrilled with how straight and fair the hull half is. At this stage it looks like a light sand prior to glassing is all that will be required.
I must say taking my time heating the foam evenly in an oven and placing the foam with care has really paid off.
I just hope I can replicate these results on the next half.
Below are a couple of pics.

As we are going into summer and the weather is getting warmer I asked some friends around yesterday to help laminate the outside of the hull. I wanted to make sure it could be done and a vacuum achieved within the resin's specified vacuum window.
The previous week I managed to laminate the deck and side down to the gunwale.
As usual I weighed everything that went into both and everything that came out. Just to keep track of how things are going. I managed 21 inches of mercury vacuum on the hull and 25 for the deck.
The end result was a 43% resin content in the deck and a 44.27% resin content in the hull laminate. Both laminates look perfect. I'll post some pics later on when I get them off my camera.

I managed to glass the deck with 3 sections of glass.
An overlap across the deck at a point where and extra piece of glass was required for additional reinforcing.So the join does two jobs at once. The cloth wasn't quite wide enough and so another section had to be added near the gunwale. That area will have to be faired once the wingnet lacing tube is added anyway.
I used drawing pins to hold the glass in place until I had enough resin on the cloth to keep it there. Then the drawing pins were removed. Some pics are below.

Here is a pic of the hull under a vacuum. Unfortunately I didn't take a pick of the deck under vacuum.

I took some time off from boat building and restored a rusty old Mangle and turned it into an Etching Press.
They say a change is as good as a holiday and quite enjoyed the break playing with the welder and lathe in place of glass foam and resin.

I can't wait to get back to the boat now.