building new amas/floats from recycled beachcat hulls

Fairing with a long board5ft/1.5metres, I used spray on quik grip which stuck the sandpaper evenly, my arms are jelly and it was quite a hot day. I wasted some effort/Qcell by using the belt sander before fairing with the longboard , some stuff just has to be done the hard way and there is no way of avoiding it. I think I'm more than half way through, probably 6 hours sanding and 4 Q cell mixes to go. I could spray a weak paint , let it dry , then longboard , then carefully belt sand... maybe later towards the end .

 

A longboard beltsander comes to mind...

Good progress TTLF.

 

Thanks BlueBell, yes a long board belt sander would be nice...but if I make sure I eat plenty of protein, I'll end up a fair bit fitter, who needs a gym..ha.

 

I've had one month off and started this in April, eeek, I've been trying to get to the boat and work on it for a few hours at least twice a week for most of the time and I've put in many 6 hour sessions. Since the fairing started I have lost some gut[for now] , and ran out of q cell just before[..?] finishing, I knew it was going to take longer than expected and spent way too much time on detail and getting the dagger board cases strong enough to semi foil one day, fairing in between layers on the cases was time consuming and overkill, should have used finer matt.
Old multi's recent advise on being honest with what you really want ,need, can afford ,... the statement of requirements, was a timely reminder, the foil thing may well have been folly, unnecessary weight, limited purpose for fast cruising and time/ expense in building foils, one day. You need to be a little obsessive to build ,plans would help contain the urge and the dream flares.
The purpose is to sail solo, be 3 hour fast passage capable, pull up on beaches and hang in shallow protected anchorage, so the double skins and toughness may be worth the weight or wait. Next is a dynel mat about 4 ounce[105 gram] over the hulls to keep the Q cell in and add strength, then 3 coats of epoxy when it's all ready which may require a plastic tent if it takes another month to get there.
There's no going back and it's satisfying work, I don't think that time/productivity efficiency or project management is my long suit...ha . perhaps I can learn from this...best not start the old car project that's waiting when I've finished , but I like it and surely it wont take that long or be expensive...ha.

 

I had a bit of a setback that has taken a week to rectify, one of my microballoon mixes didn't go off. At the time I wasn't too worried and just laid a hot mix over the top...But a week later it was still tacky so I decided to remove the set skin and start again. I still don't know what went wrong, but the law of averages and doing so many small mixes probably explains it. My guess is that I made the mix late afternoon with a fair bit of humidity in the air that hung about with low temps, or a sea mist overnight. or I stuffed up the catalyst ratio somehow ... anyway I 'm nearly back t where I was ..messy business that.
I'm considering chopping out the Hobie 18 hull bottoms ,they' re extra weight and only useful if I hit something offshore[buoyancy bladders will be installed anyway] . I'll be sailing solo so the extra protection is piece of mind but is it worth it? I think it would add 10 to 15 kgs [22to 33lbs ]don't really know mb more,.. in each hull , the hulls are going to end up around 100kgs[220lbs]each. I don't know how important that extra weight is relatively, I'm thinking not very...21 ft long 30 inches tall roughly in not very floaty hobie 16 form forward
if it brought the weight back to 70 kgs each I think it could be worthwhile..
It is so easy to get caught up with racing hype/efficiency, ,weight is anti multi..

 

Dunno mate, 100kg seems a lot of weight for a smallish float, I'd definitely look at putting it on a diet, 60-70 kg sounds more like what you would want.

 

Thanks Corley, They will inevitably put on a little more weight sitting on the mooring for years and loading them on to a trailer, which is an option in a few years, becomes more like hernia material at 100kgs.

 

Going a little stir crazy here, I rang the police this morning, apparently boat building is deemed non essential, now where is the mental health in that, I wear a mask and protective overalls, my resin smell is like a shield of steel, To quote Dr Smith from lost in space," oh the pain"

 

I finally got back to the boat today, one small area on one bow, about a square foot 2mm thick had blistered. After getting rid of it another thin layer underneath was a little chalky,I must have overdone the Q cell ratio and or the mix was going off when I worked it on.
This fairing caper outside is actually quite fun, well doing the sanding anyway, mixing up and applying the Q cell not so much but I rarely cop the fumes.
At some point I'm going to have to call it on the fairing, blending the various underlying shapes could go on for a very long time otherwise. I like the hulls ,it's good to be finally back working on them.
I will go in and remove the bottoms of the H18 hulls, except around the daggerboards, and I'll leave some strips in to act as kind of thwarts/ cross bracing.
It is unnecessary weight and if one hull gets a hole I still have 2 more to keep me afloat.
It also gives me access to the inside of my original joins which are now stringers that I can then detail easily.

 

In the interests of losing weight I cut out most of the bottom of the H18 hulls, by doing so I've created work and probably will save say 7 kgs 15 lbs from each float. There is peace of mind looking carefully at the inside, I'll sikoflex the joins from the inside and detail the fresh cuts that I've made.
I'm now going over the outside skin with a random orbital and getting ready to lay matt and move into the last phase of fairing these hulls. I'll have a go with a flexible long board just to check.
It has given me the chance to cut out and reglue any delam areas.
I did have some issues with some Qcell mixes not taking up the catalyst properly particularly with very light floury mixes. The way to avoid this is to thin first with acetone which will help the catalyst mix.
I will just glass in a couple of the hatches that have been cut out and add some matt to the inside skin to strengthen the deck.
I'll use aluminium angle to edge/ finish the hatches and borrow from wharram the approach to hinges, a cam catch and add a cleat that ties off some dyneema so that the hatch stays battened down in rough weather.
It looks like there is a lot of rocker in the amas but because the forward section is Veed and the aft more rounded I think it will sit fairly flat and not offer much resistance forward at a resting displacement.
I'm a little gobsmacked at how the weight has steadily climbed , hanging 100kgs off each beam set[there will be 12 beams so 18 kgs /36lbs for each] is making me think carefully as to how I can truss that load effectively. But I'm on my 2nd drum of 20 litres of resin and by laying 56 metres of 400 biax at 200mm width as stringers plus beefing up the cases it all makes sense.

For me the it's important to focus on cruising and sea kindly practicality more than outright racing performance, but enjoying the influence and accepting the trade off. When it's finished it should have a waterline of 25ft, 18ft beam and weigh 700kgs /1543.24lbs as a guess loaded with provisions .
I'm re reading old threads again and comprehending a little more each time. Thanks to all that explain and detail their experience and expertise freely.,

ed.. thanks revintage I was just trying to delete the double post ,not your like..ha . hope your tri project is going well..regards

 

Your really making it hard for yourself using Qcell, use microballoons with just enough Qcell to stop slumping.

 

I think we started this off discussing weight. How much does a H18 hull weight?
Now it's up to 100KG - 220#?
You could have done a lot better by making your own strip planked hull. I bet it would have been less than 100#.
Saving 240#.

Then you could have invited me for the launching with out overloading.

PS: 12 beams??????????????

Can we see an overall picture?

 

I've pretty much finished with the Qcell, in theory..ha.., a wipe over thin mix with a fair bit of acetone should do it. I'm pretty sure microballoons are Qcell.
Unless I'm missing something..

 

microballoons are hollow phenolic spheres and q cell is hollow glass spheres, both are used for the same purpose of making a lightweight easy to sand filler when mixed with resin and a little silica to prevent slumping. I think redreuben is confusing q cell with cabosil colloidial silica.