Alan's F-39 Blog

Starting on the Main hull

2011-10-09T03:09:00.000-07:00

I finally found a suitable space to rent to construct the hull and floats. Continuing my back to front build, I have decided to get started on the main hull and leave the floats till later.

Form frames and battens. I made the chipboard form frames some time ago and found that they have all done a little bit of warping/twisting/splaying, and being generally unhelpfull. They are also in 2 parts as the 4'x8' sheets on their own are not tall enough. I have added extra height on some bottoms, and some have extensions on the tops. I have had to spend a lot of time geting them back to upright, flat, sqaure etc.

If I ever did this again, I think I would avoid using chipboard. It is heavy, brittle and prone to distorting. Any money I saved by using this rather than MDF, has probably been spent on expensive jigsaw blades to cut the stuff! Beginning of the planking

I have copied Henny's (fram.nl) method of using battens to temporarily hold the foam rather than clamps but with the addition of a small block on the batten to keep the edges butted up tight together.

I have opted for 9' wide strips, -it does mean a lot of strips to fit, and many seams to be filled, but I found it quicker to thermoform and fit this size rather than struggle with wider pieces. If you give the foam too much heating it tends to expand and distort. I give it just enough to take out the stress and relax enough for the screws to hold it well from behind.

Beam Baking

2010-11-20T04:49:00.000-08:00

I am using a similar arrangement as before, but with an additional 60W bulb. 6 in total. Could really have done with 7 to speed up the process and produce some extra heat.

Bearing in mind that there is 60/70Kg of resin and glass in the beams, it is going to be a slow process to heat them up to 50C. There are 25 plus layers of carbon and glass in places, and the heat is going to take a long time to reach everywhere.

I wanted the hot air to be able to circulate all around the beam, hence the side struts to lift up the cardboard.

Cardboard creation. Unfortunately the heat loss from this was too much, and I had to add a lot of blankets and some old rugs to keep the heat in. Coud have done with another bulb, but would exceed my dimmer switch wattage rating..

Initially the heat distribution was rather poor. The hot air was trapped underneath the beam by the sides of the ladder, and was not getting up to the top surface well (15C difference between top and bottom). I had to add 2 small hot air/cool blower fans (8.99 GBP - Amazon!) in at each end to circulate the air better.

Finally getting up to temp after about 36 hours! The light bulb method is v slow for a big heavy part like this, but on the other hand you do not have to worry about it all going ballistic and frying the thing while you are away. I think the maximum heat you can get from this arrangement with no heat losses would probably be about 60C, which would not do any damage.

Postcuring daggerboard and rudder

2010-11-14T09:01:00.000-08:00

I thought it would be a good to idea to postcure the daggerboard and rudder parts for extra strength, as they are not going to be exposed to much heat when in position. It is not strictly neccessary, as I have not been using slow hardener on these parts. The beams on the otherhand I will have to postcure as I used slow hardener on the multiple layers of carbon UD.

I am reasonably happy with the foil shape. although it has taken more filler/fairing mix than I had hoped for. I used a template CNC cut from the daggerboard DXF file for the final shaping. Strictly speaking I think I should have postcured before filling and fairing. Hope all the filler does not shrink and crack off!

The heat source. 5 x 60W light bulbs plus dimmer switch. I have found this to be very controllable.

Heat source under the board. The bottom edge of the board did get a bit hotter than the top, but on the whole the heat rising up from below was quite well distributed., about 5C difference between top and bottom.

Rather crude cardboard oven. But it did the trick OK ( with a bit of additional room heating to cover the heat loss from the cardboard) . It is suprising how long a large piece like this takes to heat up. (and cool down!) You begin to think that you are not giving it enough heat, but in reality most of it it is being absorbed by the board for the first few hours or so. After that you can begin to actual get the temp up a bit. As the board has a wooden core, I did not want to get it too hot. In the end it had about 24hours at about 45C. (Cure for the resin I am using is 50C for 16 hours.) Hopefully this will be about equivalent.

Oven No:2 for the rudder/sleeve/gudgeons/composite chainplates/bowpole/forestay backet fitting. A smaller volume to heat up, should be a bit quicker hopefully.

Rudder Case

2010-10-22T01:46:00.000-07:00

The rudder case design is such that the rudder blade itself can be raised up and down as neccessary for getting in and out of shallow water. This gives better steering control than the kick back style of rudder where very little of the blade is in actual contact with the water.

Sleeves is made by laminating around the rudder blade itself. Flanges made from some foam cut offs, and will be pulled off after laminating

I think the idea that the sleeve will slide off sideways is a little optomistic. Fortunately because the trailing edge end is open, you can prise the sleeve sides apart slightly. Then I pulled some thin strong string down to the leading edge each side, (breaking the resin/tape seal) -then with a tap from a rubber hammer, it just jolts forward slightly and then could be worked off.

Case off, make sure you get it the right way up for trimming! The top and bottom angles are not the same.

Attaching the tube to the sleeve and getting it parallel and perpendicular is tricky to get right, -get it wrong and have wonky rudder! I thought this set up plus gravity should help, as there is very little in the way of referrence points to tell if it is correct or not.

Final laminations added - now need to cut slots for the gudgeons

Slots for gudgeons. Angle grinder and power file. Very messy- black dust everywhere. (Case shown upside down)

Marine carpet for the case lining? Well I hope so. I asked Ian Farrier what "marine carpet" was, and he directed me here, (but also said that it is no longer available!) :

http://www.office-furniture.com.au/Fabric-Options/Fabric-Options/Front-Runner-Fabric-Range.html

However it still seems to be available in the UK -as shown above . It appears to be the same material (named - Front Runner Fabric) - it matches the description well .But it does seem thinner than I was expecting. In the uncompressed state it is about 3mm thick, but when squashed goes down to about 1.5mm. I may need to use a double layer I think. (Actually IF say do not use 2 layers, rudder would move in sleeve and steering would be spongy/rubbery)

Attaching the steering arm to the case.

Mold for making a removable sleeve. The flange plate is my idea to help pull of the sleeve after laminating.

Sleeve laminated on. These small pieces of cloth are a pain to cut and work with. They keep on lifting off around corners and are prone to distorting badly.

Trial fitting the quadrant, -getting it perpendicular to the pivot pin is important. I am still not entirely happy with the carbon quadrant, and have decided to line the slots with 3mm Aluminium to try and prevent the steering wire from eroding the carbon over time.

Rudder construction

2010-09-16T08:48:00.000-07:00

I had the rudder core CNC shaped, as it was a rather tricky shape to do by hand because of the eliptical tip and reducing thickness down the board. You also need a (curved) rebate for the carbon unidirectional which runs up either side.

The basic core with a rebate for the Carbon unidirectional either side.

The centre HD insert is cut out and then laminated and replaced. This was quite awkward to do, mainly because as soon as you cut out the HD insert, the core is reduced to a twisting floppy piece of foam, and you could quite easily loose the shape.

It would have paid me not to cut all the way up to the top but to leave a brace across to maintain the shape.(alternatively leave the core oversized at the top and trim to final size AFTER glueing back in the HD piece). Getting the insert back centrally is tricky as you cannot do it on a flat table as it just falls through the other side because the rebate edges are higher than the center section of the core.

First layer of cargbon on.

Bagging the first layer of carbon.

Ready for the Carbon UD

One more layer of Carbon all over, then lamination just about finished.

It now joins the daggerboard for the tedious business of final fairing and shaping. I thought I would try and make some guide rails for the final shape, rather than slapping fairing mix on freehand.

Bobstay/Screacher bracket thing.

I opted to buy the Carbon bowpole, (which is sliding fit into the forestay/bowpole sleeve which I made some time ago) but it does need a fitting added. Top part is where the screacher furler will attach, and the lower hole is for the wire from the bobstay fitting attached to the hull on the bow.

The bracket, (made from carbon), and a slot cut in the pole for it to fit into. Bushes will be fitted in the G10 tube later.

Trial fit. Goes in at an angle a butts up against the aft sides of the slots.

Laminated in place, and bushes fitted. I could only just reach inside the pole (with a bare arm) , to get the cloth in place, -ended up with resin stuck under me armpits! Yuck!. Also end cap fitted.

Composite Quadrant

2010-08-09T02:21:00.000-07:00

I thought it would be worthwhile to make a composite quadrant for the steering. (10 inch radius). The one specified in the plans is available, but costs about 150GBP, - has to be adapted and is a lump of bronze weighing about 5Kg! It is a standard quadrant for a pull/pull chain and wire steering system

The basic quadrant shape.

The intention was to have a thick flange around the curve and then carve the slots for the wire into this. A thinner flange down the sides for extra strength. . I will make 2 pieces like this then glue them together. I thought of trying to mold the slots in while making it, but even with vacuum bagging I don't think the carbon would have gone into that sort of shape.

Bagging the carbon. Also making a composite quadrant shelf for the sheave idler.

Glueing up the two halves

The flange at the front turned out not to be thick enough for both the wire and a deep enough slot to stop it slipping out. I had to add some more layers around the curve to compensate for this. Also thickened up the corners, this will allow a larger radius for the wire to go around to the fixings. (Less stress on the wire) The wires will run against the original piece, and the extra layers will just be to allow for a 8mm or so slot. to keep them in position.

Extra layers around the curve and corners. Needs the slots cutting in for the wire , and some fixings for the tentioners to be added on each side

Cutting slots with an angle grinder. Crude but effective. The blade was not thick enough for the slots I wanted, but after cutting the initial slot it is easy to widen it a little by just slightly angling the grinder off the horizontal.

Side terminaters for the wire bonded on.

Finished. The weight with the lightening holes is 1.1Kg, which is a good saving (4Kg) on the weight of the bronze one I could have used.. A sleeve will be bonded into the centre of the quadrant later which attaches to the sleeve/cassette in which the pull up daggerboard rudder blade is held.

I am begining to wonder if the carbon fiber will be eroded away by the constant motion of the wires in the grooves.( It is not very abbrasion reistant unfortunately) It may be neccessary to fill in the slots with a high density resin putty and then recut them!. I had a comment suggesting using Dyneema (synthetic rigging rope?), instead of wire, -this is a possibility I guess as long as the rope does not get to abbraded in the conduits which will lead from the steering pedestal to the quadrant. Rope would certainly be less damaging to the carbon fibre.

Gudgeons and start of rudder

2010-07-20T01:41:00.000-07:00

I thought I would make some of the parts for the steering. I don't know what the final arrangement will be but I will be needing a rudder, sleeve, gudgeons and some sort of rudder web to attach the gudgeons to.

Gudgeon mold and released laminate

More layers inside. Messy and sharp!

Trimmed and cut into 2 slices (on bandsaw)

A piece of modern art - no just trying to get HD fill level. God bless hot glue!

Finished gudgeons.

Cutting foam for the rudder. Cut outs for some of the HD inserts.

The foam sheet I am using is very warped, (and perforated,) so I had to make a good resin proof flat bed to glue the foam blank up on. I want to get the core CNC shaped, and to start with a warped blank would not be good at all!

Ready for glueing. As I don't know if the CNC shaping will be done in one piece, or 2 halves I am just glueing up the two halves at present. It is also more difficult to keep 4 layers plus inserts in the right place. Easier to just do it in 2 layers to start with and then glue these two together later..

The finished rudder blank, ready for shaping. It has taken quite a lot of work altogether. I find glueing up large areas can be problematic, as it is hard to judge the thickness of the glue you are putting on. (I am also admit to being a bit of a messy gluer!)

I had problems because the HD inserts which I glued up seperately from the main board ended up being a fraction thinner than the rest of the board. It means when you glue these in place you have to try to hold them centrally in the board. (The centre glue line of the board is the ideal refference point for the shaping) The board has a bit of flex to it as well. I will have to be careful when laminating that nothing is under any stress or flex.

HD and nomal foam

It would I think have been better to do it all in one piece and vacuum bag it. This would have kept everything in the right place and even. Fortunately the board is over thick by about 5mm per side, which should mean that there will be enough material for the shaping.

I have added an extra area of HD foam around the tip and leading edge, just for strength. If you hit anything under the water, this is the area that will make contact first. first.

I seem to have found a company place which will shape the block for me on a 5-axis CNC machine. We decided to do it in one piece, rather than two. This is mainly because the trailing edge of the finished (slightly undersized) blank is only about 3/4mm wide, -on each half this would reduce to 2mm, at which point the foam is going to disintegrate or get damaged. It also means that you would not have to glue up the two halves and worry about them slipping about.

Daggerboard

2010-06-03T02:38:00.000-07:00

I started the daggerboard about 18 months ago, but gave up on it for a while, partly because it is rather tedious and partly because I was not sure how to maintain the correct profile up and down the board. The core is shaped from Western Red Cedar. Once you have started shaping, there is very little in the way of refference points to keep you on track.

I removed as much material as possible using a router, but this is a bit limited as you get up to the non shaped area. The only refference point I really have is a good center line up and down each side .I thought if I could get the correct profile (at the right angle) on the leading edge and trailing edge, this would at least be a start.

The shape is on a sliding piece of wood that should hold it perpendicular to the side and on the center line aadn at the correct angle..

The trailing edge is straight for about the last 12 inches which is easy to shape.

When I started the daggerboard, I did not know that it was possible to buy a ready made blank, (Phill's Foils,or I think I would have gone for that.option. I had already bought the wood and glued up the board, so I thought I might as well try and finish it. The only plus side is that as the wood has been indoors for about 18 months, it is very well seasoned and lighter now than when I left it before.

I found an interesting article about designing and making foils here: http://www.gurit.com/core/core_picker/download.asp?documenttable=libraryfiles&id=1113 , actually from SP systems who manufacture the Ampreg resin I am using. It seems that for the stiffest board with minimum tip deflection, carbon UD either side of the board is the way to go.

Laminating the Carbon, centered on the widest part of the foil shape. I wish that I had sealed of the wood first as I had some bubble trouble under the UD. Before laminating the rest of the board I sealed the wood off with 2 coats of resin, and this put a stop to that.

To avoid any distortion across the tressels I stood the board on its side before the Carbon UD layers were fully set, and did the same with the glass layers.

The trailing edge is very thin and prone to damage. (especially on the undersized blank.) I think it would only take a small ding on this edge, and there would be wood and water contact. To avoid this I replaced 2 inches of the trailing edge with a HD putty mix.

I would have liked to have done the same on the leading edge, but I should really have done this before shaping. To compensate a bit I have arranged it so that there are 2 layers of glass over the leading edge and also over the tip.

Wrapping the board up.

Board glassed all over. The shape is not yet 100%, but I thought it was best to get the Carbon and glass on first and then do the final tweaking. I am pretty sure that it is a little undersize, and will need a bit of filling and fairing to perfect the shape. Weight wise I reckon it must be in the 18/ 20Kg area. I can just about lift it on and off the tressels on my own.

Sealed holes for the pull up/down lines

Beam/float sleeves and a few repairs

2010-05-14T01:02:00.000-07:00

I was not very happy with the laminates around the bolt on the tip of the beam. When I did the "wraps", I slit the cloth and tucked it around the bolt, but it did not co-operate, and left a lot of air and lumps and bumps. I decided to grind them out and fill with hd putty and patch as well. You then need to recreate a flat surface perpendicular to the bolt, for the nut to tighten up against.

I used the nut and some cut offs of MDF for that. Will be wrapped in plastic tape before use.

I thought I might as well make the float/ beam sleeves while I was at it. Made by wrapping fiberglass around the tip area and then pulling off.

Fairing mixture on the tips to just above the float deck level.

Fairing off the tips and re-drilling the pivot pin access holes in the beam sides. I found that shining a bright lamp down the slots in a darkened room lit up the pivot holes very well underneath the fiberglass. These holes had been sealed of with a foam plug and some hot glue. I was able to drill them very accurately using this method.

Tips faired off.. The geometry is such that the sleeve should not get locked on due to the shape. The tip is tapered up/down and sideways. In fact once you have managed to get the sleeve to move even a couple of mm, the whole thing should then slide off easily. (In theory!)

Resin proofing the tips. Parcel tape and wax. I find that although it is true to say that the resin does not stick to plastic tape, it still needs a bit of a jerk to come off. I may make a couple of handles somewhere on the sleeve to give me something to hold onto when I try to pull them off..

Getting the cloth ready. To be continued....

The bolt on the tip has been a constant nuisance, it is just begging to get damaged or covered in resin!

I made a raised ridge where the sleeve will be trimmed off , it should save me damaging the beam itself, and means there will be less sleeve to try and get off.

The sleeves laminated on.

I glued on the bolt washer on the aft beams with HD putty, but this was not a good idea and just made them harder to get off.

After laminating, none of the sleeves would budge at all.! In the end I bonded on some wooden blocks and used a hammer to tap them off. But before that I did as much as I could to break the seal between the plastic tape and fiberglass. I used a 12V car tyre inflator to pump some air up the sleeve. This broke the resin/fiberglass seal in some places, but not over the tip or down the sides. It is also difficult to get a proper seal around the edge of the sleeve. I used some vacuum bagging rubber tape. Without breaking this resin fiberglass seal first, I very much doubt weather I could have got them off at all.

Wooden blocks bonded on the sides and pointing at the tip.

Success. They are a very tight fit around the beams. When you pull them off, there is a suction/vacuum effect trying to hold them on. A small hole drilled in the tip helps to release them.

Aft beam sleeves finished. And no resin in the bolt threads. FWD beam sleeves are still stuck fast, and the air compressor has broken down. (I may have burned it out by running it from a battery charger, I am not sure.)

Anyway I am awaiting a replacement, as the sleeves will not budge at all without some more releasing under the fiberglass.

Fwd beam sleeves finally finally off! Bastards! What a struggle - hours and hours of agro and frustration! Using compressed air did not work as it is virtually impossible to get a good seal around the sleeve. They would just not come off with tapping alone, (wood blocks got completely mashed with hammering) and in the end I had no option but to try and cut them off, without damaging the beam. Not a happy situation to be in. I am doubly annoyed because my gut instinct when I laminated these on was that they would not come off. The shorter AFT sleeves yes, but not the longer FWD ones. The whole thing is a recipe for disaster. You cannot physically exert enough force to overcome the friction/tightness.

In the end I managed to push an old hacksaw blade partly up the middle of the sides, and then using a Feinmaster type cutter, I made 9 inch slits up the sleeve sides, trying to cut on top of the hacksaw blade. This released the tightness just enough to let me prise open the tops and bottoms with some very thin wedges and push an old bandsaw blade up to the tip in places, thereby breaking the resin/plastic tape seal. Most of the time the blade just tears up the plastic tape and sticks, but I managed to break just enough of it so that it would tap off. The suction/vacuum effect is even stronger on these sleeves, and a hole drilled at the tip definately helps to prevent this.

I have to say nonsense like this really leaves a bitter taste and tarnishes your view of the whole project. You wonder how much punishment you want to take. I now have the pleasure of repairing the sleeves and some of the side layers on the beam itself. As a final insult, the plastic tape came off in 5000 pieces and left most of the stickness behind! Urgh!

On a lighter note thank heavens for Devcon 5-minute epoxy and the Bosch multi-tool!. The epoxy is expensive but very impressive. Within 10/15 minutes of bonding on the wooden blocks I was able to hit them with a small sledge hammer and they did not come off at all. I have had to cut/chisel the blocks off.

The multi-tool is definately my 2nd most usefull piece of kit (after the Black and Decker Power file). You can plunge cut into materials, and it cuts even fresh or thick laminate very well without damage. It is also cheaper then the Feinmaster.

More Beam work

2010-03-03T05:09:00.000-08:00

After fitting the lids, the entire beam needs to be "wrapped" in 2 layers of fiberglass. This has proved to be the hardest task so far, it is partly a physical problem (beam is heavy and awkward to move), and partly a problem of how to "wrap" a curved object in flat cloth, without distortion. As you need access to the recess mould and folding system slots, it ideally needs to be upside down. You also need access all the way around, and yet need to support it.

Dry fitting the cloth in the reccess mould

and folding system slots (Actually I found later that it is easier to cut the slots when the cloth is wet, otherwise it tends to start falling apart.)

I originally intended to try and do it in one shot, but as the top photo shows, this would involve upside down laminating, and having to move the tressels as you go along. In fact you have to cut the cloth so that the overlaps are in positions where you can move the tressels without the beam overbalancing. The alternative is to have to turn over a wet sticky beam half way through laminating, something I wished to avoid. I tried putting it on its side, but it was not very stable, and the cloth around the curved area seems to distort more.

In the end I opted to do it in two stages. Bottom and side overlaps in one stage, and then when dry, turn over and do the top and side overlaps. That way there is no need to move tressels or turn the thing over.The only downside is that because I need to do this wrap 2 times on each beam ( once before the carbon UD and once afterwards ) I shall have to do this lamination 16 times in total!

Bottoms done (FWD beams)

and tops. Now ready for the Carbon UD top and bottom

250lm of Carbon UD. Expensive and really quite heavy. I don't find it particularly easy to work with in practice. The fibres are very densely packed. It is slow to wet out and very difficult to to remove trapped air unless you over saturate it with resin. You can chase bubbles around endlessly. Also if you inadvertently snag a strand on something sharp, you quickly end up with a "bad hair day".

FWD Beam bottoms finished. These are probably the hardest to do. There are XX layers on each, plus all the slots to be cut out. It is difficult to get the cloth in the right position first go. If you try and pull it off for a second attempt, it will unhelpfully pull up the layer underneath and start distorting. With so many layers I have used the slow hardener, to avoid heat build up, but it will have to be postcured at a later date. I am glad that the Aft beams are shorter overall and have fewer layers!

Laminating Carbon UD on the tops

Finished and peel-plyed.

Final wrap of fibreglass over the entire beam. Nearly there . Just some extra layers over the sides to do, then finished for now. Beam fairing will be added later after checking the folding system alignment when beams are attached to the hull.

I have to say that the beams are dissapointingly heavy, (but very solid!) With one across the tressels as above, I can lift the tip end up a few inches with one hand, but the overall weight must be in the 50/60Kg area I would guess. This will make folding/unfolding harder work I think.

I know that a finished F-32 beam with fairing weighs in at about 28Kg, and that according to an email I had from Ian about ready made F-39 beams, that they are " much bigger and stronger" than the F-32 ones

I could not find the exact weight of cloth as specified for the beams and had to use one that was 50g/m2 heavier, (with resin about 100g/m2) . This particular cloth also has slightly course pattern/texture, and even though you have thouroughly wetted the fabric, you still need to add extra resin to fill the pattern/texture, otherwise it will not peel-ply well. I reckon for about 2.5Kg of fabric, I am using about 3Kg of resin/hardener, which is not really very good,- excess weight.

I did have a much nicer cloth from my supplier at one point, but was unable to get any more. It was much smoother, soaked up resin quickly, conformed well around corners and peel-plyed very easily, but fell to bits very easily. I wish now that I had taken the trouble to track down some more of this type.

On the plus side, for the multiple layers of Carbon UD, on the tops and bottom, I managed to use a bit less than 50/50 resin/glass. Generally I find that where you are laminating multiple layers (about 3 or more) you seem to be able to use less that the standard 50/50 ratio.

Most of the overlaps I have made, (and there are quite few) are also a bit wider than neccessary, but the 45/45 cloth I am using tends to disintegrate along the edge when you cut it, so to be on the safe side, you end up making the overlaps bigger. But again more extra weight.

I have also foam filled the beams which has probably added about 6/7 Kg I reckon. The Carbon anchor assembly probably weighed about 6Kg, and Upper folding slot recess about the same.

As I am going to postcure the beams anyway, I wish I had made greater use of the slow hardener, -the mixture is a lot less viscous than the standard hardener mix, there is a longer working time and I think you can use less resin overall. Vacuum bagging would have helped, but would be a very awkward and long winded task. (At a brief look at the plans, there must be over 100 different pieces of fiberglass in a beam altogether, not all full size, but a lot to deal with all the same) . Hopefully if I vacuum bag the hull and floats this will do something to even out the overall weight of the boat.

A few more beam construction photos...

Smoothing off after replacing the "removable" strip ( actually they all came out in about 500 small bits and I had to cut 8 new pieces of foam!)

I have gone to a lot of trouble to try and keep everything smooth and flush at each stage , otherwise you tend to get small seams and patches of air under laminates, and it is also difficult to consolidate the layers nicely. As you add more and more layers, you have more overlaps and patches and a few lumps and bumps etc, and the smoothness/flatness gets lost .It makes getting the last few small air patches/ bubbes out very difficult. Rollers and squeeges tend to miss the dips and hollows.

Pivot pin holes sealed off ready for the all over "wraps" - aft beams

Wraped and ready for the Carbon UD - aft beams. Because I have done the "wrap" in two stages you tend to end up with a messy edge on the underside of the beam each time, drips and runs etc which need to be cleaned up before you can continue.

Carbon UD layers cut to side and laid out in order. Each piece is a different length and starts from a different position. A total of 108 layers required for all 4 beams. Fortunately I only made 1 mistake which was easily rectified.

Preparing the aft beams for the extra side layers. Then all beams finished except for a few small jobs like finding the pivot pin holes again!. The Aft beams are definately lighter than the forward beams, less layers of glass and Carbon overall. It is a long haul from start to finish with the beams and it gets rather monotonous having to do the the same job 4 or 8 ( or 16) times. I am glad they are now finished.

Mast base

2010-01-29T02:28:00.000-08:00

This (part) of the rotating mast base is one of those maddening little pieces that is difficult to get right, because of all the shallow angles. If you get one bit correct and nicely fitting you then find another bit has gone slightly AWOL! Very frustrating.

It did not take too long to make the individual bits, but fitting it all together and working out 'how' to hold the parts in place for welding (without loosing the pin alignment for the sheaves) has been quite tricky. The sheaves are running on a 1/2 inch stainless steel rod. I will drill sideways holes either end of the rod and fit clevis pins to keep everything in place, and allow for replacement of the sheaves if neccessary in the future

Sheaves fitted and now ready for welding.

Beams -Foam fill and top fitting

2010-01-20T01:37:00.000-08:00

I have opted to foam fill the beams with a 2 part expanding polyurethane faom. It will add a bit of weight to each beam unfortnately, but hopefully not too much. I think I have used about 6/7 kilos per beam

It is a bit of a messy and laborious business. If you keep the 2 components at the optimum temerature for maximum expansion (least weight), then you do not get very long ( 45 secs) to mix well. i.e you have to mix lots and lots of small batches. The foam produces exothermic heat on expanding so it expands well, but then has an annoying habit of shrinking back slightly, leaving gaps around where it is touching the inside of the beam sides and bottom. Fortunately the next liquid pour and gravity helps to fill these in.

If you spend too long mxing, this happens! To get the foam into all the nooks and cranies, it reallly needs to be poured in whilst it is still completely liquid.

Here, I am cleaning up. I have tried to keep the foam off the areas that will later be usd as glueing surfaces for the lid.

Ready for the lid. This has been prelaminated already on the inside face.

Lid fitted.

Daggerboard Case continued

2009-12-27T02:51:00.000-08:00

Now the cheek block has been trial fitted to the case, the sides can be joined. The insides has been coated with several layers of antifouling, as this area will be inaccessable once it is joined together.

Glueing together.

More layers of glass are then added along the hardwood sides.

Despite the core of the side panels being made from end grain balsa, this is now a large and pretty heavy piece. I can just about move it around single handed, but I doubt I could lift it.!

Case is now ready to be fitted in the hull at a later date. It will be trimed off at an angle either end to match the hull.

Daggerboard Cheekblock/Some metal parts

2009-11-11T03:01:00.000-08:00

Before putting the daggerboard case sides together, I have to fit a cheek block which will be needed to lower the daggerboard. (Might be worth mentioning that the pairs of holes at the top and bottom of the Barton block, are NOT the same distance apart. I almost ruined the backing plate by not spottig this!)

Cheek block is bolted to a backing plate which is attached to the side of the control line slot

!0 bolts are neede for the plate.The bolts are pushed through from the inner side, and the heads buried in epoxy putty.

I thought I would make some of the simpler Aluminium parts myself. I have had to buy some large blacksmiths drills and some hole-saws to make these parts, but they will also be needed later on to drill matching holes in the hull and beambulkhead flanges.etc

Drilling Aluminium is easier than I thought, even 12mm plate was not too difficult. I already have a small pillar drill which seems up to the task. The cutting and shaping I have had to do is on a small band saw with a bi-metal blade.It is slow going to cut but still easily possible. A bench sander also rounds of corners and edges very easily.

These parts are for the kick- up rudder box. The 4 large holes will have a plastic bush fitted and then a 16mm bolt. Plans specify a 16mm ID by 19mm OD plastic bush, but I found that from Igus GMBH (suplies acetal bushes as used in folding system) that they only have 16mm ID by 18mm OD. So I have drilled 18mm hole and not 19mm. (Could be worth checking that you can get the bush specified Before drilling hole!)

These are the beam bolt backing pads for the folding system - made from 12mm Aluminium plate.

Carbon chainplates and forestay bracket

2009-10-01T03:24:00.000-07:00

Carbon chainplates are formed from a stainless steel thimble and clevis pin, glued to foam strip and covered in multiple layers of Carbon UD and glass

Laminating. Difficult to keep them still!

Finished- will be trimmed to final size and shape later

The forestay bracket also serves as the sleeve for the retracting bowpole.

Attaching the foam and thimble to the carbon tube. (at the correct angle) The bowpole will be a sliding fit into the sleeve.

Building up a cone of foam around the tube

Laminated with multiple layers of Carbon UD

Daggerboard Case

2009-09-30T09:09:00.000-07:00

This can be constructed either from Marine plywood (heavy) or end grain balsa. I was lucky to find a supplier in the UK who would sell individual sheets of balsa. Normally you have to buy a full case which is expensive and more than you actually need. The panels are supplied as 4'x 2' sheets with the balsa blocks attached to a flexible backing scrim.

Assembling the sides. A plywood insert is added in the top section for the compression loading from the mast. 2 layers of glass are laminated either side of the balsa sides. I vacuum bagged the layers after making a small extension for the table, as this is a long piece, and would not quite fit.

After laminating and attaching the down pieces (Ash) , I coated the inside with several layers of epoxy. The down side of balsa is that it would soak up water if there are unfilled gaps or holes.

Photo shows the rope channel for pulling the board up and down. This has been laminated over and sealed, after digging out the balsa around the edge and replacing with solid putty. Before I can do anymore on this I need to find a suitable cheek block....

Beam fairings

2009-09-30T08:26:00.000-07:00

Made using molds traced from Full size patterns and. constructed from foam strips about 25mm wide. It is hard to get them to stay in place. Beacause of the shape of the fairing, (deeper at the outer end than at the inner end) the strips need to bend backwards and forwards, up and down and twist as well.

I ended up having to hot glue each strip to the lower strip and hold every strip in place with screws in every single mold! After that right angled brackets were used from the outside, to hold it all in place, and the screws on the inside removed before laminating. Just make sure there is enough room to get your screwdriver in to get the screws out. By the time the sides have been built up, there is not much space left inside.

The end result is rather "gappy" on the outside. It is virtually impossible to get the strips to align nicely along their entire lengths. I will have to try and squeeze some resin/putty into these gaps later. The shape is not that good either with a lot of ridges to be sanded. I think that there ought be a better way to make these. It has taken a lot of time and the results are not that impressive really. (i.e you have just created more work for yourself!)

After a bit of sanding/fairing they look a bit better. Pity I forgot to put any peel ply on the inside after laminating though..

I am going to leave the beams at this stage for the moment. There is still quite a lot more to do but I am running out of space in my current workshop. Interestingly I had an update to the F-39 plans recently form Ian Farrier, and he mentioned that several builders or potential builders had enquired about purchasing ready made beams from Farrier Marine. I can certainly see the appeal of that. It is too late for me, but if I had a choice I think it would be well worth it.

Beam Tops

2009-09-30T01:25:00.000-07:00

After removing the laminated beams from the mold, tops need to be fitted. These are the 2 aft beams which areslightly shorter at the tip than the forward pair.

The mold for the beam tops is made from the 2 cut-off from the beam mold itself. i.e the opoosite curve
I thought I would vacuum bag these as it only needs a small alteration to the mold to give a flat surface.

The mold is just made from slats running from side to side. I added this piece of 6mm ply to give a surface to bag on.

To hold it in place a few right-angled brackets were needed around the curve. Otherwise the slats were pulled out of the chipboard sides.

Positioning the foam. The black tape is covering another removable strip, which will be dug out from the otherside later on. (Same as in the beam bottom.) The slits for the strip should be completely sealed with putty before laminating. The gap at the front is where the top goes over the reccess mold. The smaller rectangle higher up is where the highest part of the UFSR will go.

Holding the faom in position without screwing from the otherside (will lose vacuum) was a bit tricky. I ran a bead of hot glue right down the sides whilst clamped down, and this was just about enough to hold it in place. ( I did have to use some screws from underneath on the bend, but I put some hot glue down the holes before screwing them in and it did not seem to affect the vacuum too much.)

Vacuum bagging

Oops ..Disaster! I did not seal the slits for the removable strip well enough and the mold itself was too rough.The resin stuck well.

I remained fairly calm under the circumstances else there would be no photos!. I just cut it all up and quietly put it in the bin.It put up a fair old struggle before breaking considering it was less than 24hr old, Even so it is a reminder of how brittle resin can be after it is just cured. I though afterwards that it would have been more economic to smash up the mold and save the part, but it did not occur to me at the time. (So far, I'm glad to say this is the only part I have completely wrecked. I hope it will be the last as well!)

Repaired mold this time totally covered in plastic tape!

Finished beam top.

Carbon anchors postcure

2009-09-25T01:21:00.000-07:00

The carbon anchor strips need to be postcured at this stage. I thought about using my domestic oven for this but found that the temperature was very variable. Ampreg 22 postcure is 16 hours at 50C or 8 hours at 70C. The higher temp is no problem for the resin, but it is too much for the Core cell A foam which I am using. I spoke to SP Systems who manufacture Core cell and they were not keen for the foam to go above about 55C.

I built a simple oven from a box, some light bulbs and a dimmer switch. A couple of old computer fans helped to distribute the heat evenly.

I gave them about 16 hours at 55C. You can certainly tell the difference with this resin as to wether it has been postcured or not. After postcure when the anchors are knocked together they sound very like ceramic/china.

Beams -Carbon Anchors

2009-09-24T09:49:00.000-07:00

Ian Farrier's later beam designs incoporate carbon anchors in place of the usual metal parts.

Getting ready to laminate the assembly. If you don't get the carbon UD started EXACTLY perpendicular across the assembly, each wrap will move sideways until it is falling off the assembly.. The sides help to keep things in their right place to a certain extent.

Anchors peel-plyed and drying. The longer one at the bottom will be made into the carbon anchors for the hull

Each anchor blank needs to be cut ino to 8 strips. The plans say to use a bench saw with a diamond blade, but I found my bench saw was not up to the job really. On top of this it was carving out about 5mm per cut. That would end up turning 35mm of precious anchor into dust! (There is about 20mm of anchor to spare which includes any edge defects). I opted to have them cut by abrasive water jet in the end. It was expensive but worth it, and they turned out very well. Even the foam did not get damaged by cavitation from the cutting jet.

Beam mold continued

2009-09-24T08:27:00.000-07:00

The mold needs to be quite strong and sturdy. By the time it comes to take the beam out of the mold, it is heavy and awkward. I reckon it must be in excess of 20Kg, on top of which they are an awkward shape. (When you lift them up from both ends to get them out, they immedialely try to fall over sideways) I could not get them out of the mold without assistance. Recess mold at far end, as positioned by the template mentioned above.

To make sure I did not have any extra proplems with sticking resin, I opted to entirely line the mold with parcel tape. It could well save a lot of agro, -the last thing you want to have to do is bash the mold around to get the beam out. That would be a sure fire way to upset the alignment.

Mold is about 3m long in total. I put it in the only available space I had, but it would have been a whole lot easier if I could have walked all the way around it more easily.

Mold lined with foam. I chose to line the Recess mold with a loose fit resin proof plastic cover. In practice, when it came to getting the beams out of the mold, it was actually easier to unscrew the Recess mold from underneath and lift it out while still attached to the beam. It could be removed later easily. The central strip towards the outer end of the beam is where 2 cuts have been made. This strip of foam is removed later from underneath for further lamination to be done.

Beams -mold making

2009-09-24T04:59:00.000-07:00

Basic mold is made from 2 sheets of approx 4' x 9' sheet materials 18mm thick. The critical thing with constructing this mold is getting the pivot pin alignment holes in the right place, and perpendicular to the sides of the mold and parallel to each other. The shape and curve of the mold are defined by a template made from the Full Size Patterns (FSP)

I bolted the 2 sheets together before drilling the holes in an attempt to prevent any misalignment. Even so, it is tricky. Plans suggest using a drill press, but in reality humping 2 heavy sheets 4 x 9' around is really not possible. In the end I brought the drill press to the sheets, and then had to try and get it all level and wobble free etc. Infact unless you have a drill press with a deep throat, you cannot actually get near the second hole.
The white tubes are where the pivot pins will go in the final beam. Have to make sure the sides themselves are dead upright and parallel to each other first. otherwise you cannot get the tubes perpendicular and exactly level across the mold.as required. I struggled for several days before I was happy that all was OK.

The template is made from the FSP and is to check the relationship between the pivot pins and the top of the recess mold, which is important for correct beam/float alignment. Also a good check that the pivot pins are in the right place, and that the reccess mold is the correct shape. (Has sloping front and sides, and was a bit tricky to make). Sliding the template across the mold from side to side does at least check that the pins are parallel to each other

Close up shows things look OK

Doorway/passage way

2009-09-20T02:09:00.000-07:00

Both of the Fwd beam bulkheads have doorways in and 1 of the Aft ones has a passage way to allow access to the Aft cabin. A flange is formed around the doorway cut out ( on one side only) - many wraps of UD fiberglass which is bonded to the bulkhead with tape on both sides of the bulkhead . Photo shows the mold for the flange. The peel ply will save me having to sand shiny epoxy later when I need to tape around to the other side..Photo shows Stbd b-head.

Lamination finished and mold removed. (Port b-head).

Finished flange on Stbd FWD beam bulkhead now trimmed to size. This bulkhead now finished and ready for bonding into the hull at a later date. Extra layers have been built up around G10 pivot pin tube.

AFT beam bulkhead with passage way. (Sorry poor photo) Also a flange has been added which runs from the outer edge of the slot across to where the cockpit sea will bond later. Another 12 layers of UD! Beam bulkheads are now quite heavy and awkward to move with all the layers of glass and resin which have been added. Other photos show close up of flange area which is now very thick with solid laminate. Also collection of bulkheads ready for fitting to the hull

Bulkhead lamination

2009-09-20T01:40:00.000-07:00

8 layers of fiberglass are needed over the mold and flanges, each slightly smaller than the one before. Strips of Unidirectional fiberglass (UD) also go in this area and down the outer sides of the bulkhead. Cutting the glass for these shapes is a bit tricky. I made this weird looking template to speed things up.

Laminating the layers. Perhaps I should explain the different resin colours. The resin I am using Ampreg22 comes with different coloured hardeners. Yellow is fast/ Purple is standard and Green is slow. Because of my previously mentioned problems with the distorting plastic on the mold sides, I used slow hardener for these layers. The downside of the slow hardener is that it has to be postcured, whilst standard and fast do not. I prefer to use the standard hardener when ever possible.

Photo shows the UD point reinforcement layers sandwiched in between the other layers. 5 wide strips and 8 narrower ones.

Partially finished bulkhead slot area with the mold removed. A mock up strut seems to go up and down centrally in the slot which is a good sign!

Beam Bulkheads continued...

2009-09-19T03:54:00.000-07:00

Molds reattached to the bulkheads. Despite having tried to keep all the holes in the mold exactly perpendicular to the mold sides, when I came to check it, I found there was sufficient play in the alignment for errors. This little set up was to ensure that the 2 pieces of G10 tube with acetal bushes (lightly tacked to the mold sides) were correctly attached to the mold. Lining the hole with thin sellotape also helped keep the alignment rod tight while the G10 tube was glued on.

Trying to get rods and tubes perpendicular with set squares is a bit difficult as the edge keeps slipping ot the round sides. A couple of straight strips taped on helps to make it more accurate.

Aft beam bulkheads ready for laminating. Molds (which are wider than the panel ) have been blended into the panel with large HD putty fillet around the cutout area.

Beam Bulkheads

2009-09-19T03:21:00.000-07:00

Before laminating the panels for the beam bulkheads, a high density insert is added around the area which will later be cutout.to form the mold for laminating over.

Checking the shape of the prelaminated panel against the Full size patterns. It is very important that the cutout goes back into the exact spot it came from, to which end there are two "ears" on both the cutout and the bulkhead panel..

One off the bulkhead cut out sections. The small hole is the where the stainless steel pivot pin will go later to attach the strut to the bulkhead. The idea here is that the cutout section has spacer plates added either side of it before being reattached to the bulkhead using the "ears" on the cutout. Then it is laminated over either side, before being removed, leaving a slot into which the Upper Folding Strut will pass.

Adding the spacers either side of the cut out section. The white tube and set squares are an attempt to keep all the holes in all the layers correctly aligned, ie perpendicular to the mold. Spacer are MDF sheet .

Cut out has to be made resin proof, to which end I added UHMW Polyethelene sheet either side of the mold, which was held on with tape and hot glue (glue only in areas which would be accessible after lamination!.).
( "Ears" for repositioning on the bulkhead obviously not covered which plastic).

When it came to getting the mold out of the slot it would only be a matter of slitting the tape and breaking the hot glue seal, and the centre section (cutout plus MDF) would pull out leaving the plastic spacers inside the slot which could then be collapsed inward and pulled out easily.

The above worked well except for one disasterous unforseen problem. The plans say to use 8/10mm plstic spacers, but I thought why not use 6mm MDF and 2mm plastic spacers! The problem is that when there is a temperature differential between the two sides of a thin piece of plastic it basically starts to bulge out and distort. With 8 layers of laminate to go over the cutout area, the heat from the curing resin caused the loosely attached plastic sides of the mold to bulge out and distort, which was a serious problem, not least because the carefully position G10 tube would also move (with the plastic sides) and lead to misalignment. All 4 molds were constructed in the same way and where all attached to the bulkheads and glued and screwed in position. They could not be removed without wrecking them. It turned out to be a real headache!

With Ian's advice I got around this problem in the end by lamintaing individual layers on in a cool room using my slow hardener which generates very little exotherm. After the first 3 layers where cured, they where sufficiently strong to stop the plastic sheet from moving. But it was a real pain and dragged out what should have been a straightforward laminating job into several weeks of frustration and agro including some midnight laminating sessions in a chilly room! But there you are, how many times have you been told to "FOLLOW THE PLANS!" . So if the plans say use 8/10mm spacer, you had better do it!

Adding the flanges to the cutout section

Early days

2009-09-18T01:03:00.000-07:00

I originally bought the plans from Farrier Marine in about 2006, but was not in a position to get started until Sept 2007, when I bought the first batch of materials.- fiberglass, peel-ply,release film, breather fabric and vacuum bagging film etc.

I built a 6'x8 laminating table from white furniture board panels from the local DIY store, and a simple rack to hold the rolls.

For a project of this size, I thought it would be worth buying a new vacuum pump, although it was pretty expensive. It is one of the models sold by West System/ Wessex resins. (Actually made by Becker , Model VT 4.8 -and I am sure you could get it cheaper from another source!)

It pulls a vacuum of 25.5Hg/150mbar, which is not terribly strong, but it does however have a high capacity. (i.e it can shift a lot of air quickly) This means that if there is a leak in the vacuum bag ( which there often is), the pump still has some chance of pulling a half decent vacuum. So far even with some badly leaky bags I have never had less than about 24.5Hg, which is plenty strong enough to give a good laminate.

Many pumps with very high vacuums have low capacity and can be overwhelmed by leaks. I bought 2 hoses and 2 breach units, as there are 2 inlets on the pump. With the non return valves on the breach units you can do 2 bags simultaneously, adding the second later on than the first..

As working with fibreglass was new for me, I initially started off vacuum bagging the smaller bulkheads and panels individually. This is rather a slow way to do it though, and as I got more proficient, I was able to cram as many parts as possible onto onto the laminating table. The secret is preparation, you really need everything cut to size and at hand -then there is no panic to get it together before the resin gells.

One of the smaller float bulkheads being vacuum bagged. Rack for rolls. Some finished panels in the corner. As I do not have a resin trap between breach unit and pump, I keep the pump up on a pair of old step laders. The hoses are about 6 feet long, so I should not get resin into the pump, which would be an expensive disaster!