Sunday, January 31, 2010

Bow bulkhead finished

Today it was time to finish the taping of the bow bulkhead.  The most exciting part was the front side bulkhead to deck join, as there is no way to get this join in sight.  I tried to take pictures afterwards, but it was difficult to get the camera in the right position as well.  It seems it is adequately taped however.  I accept it as it is.

The bulkhead to hull side taping was a lot easier and turned out quite well.  This completes the taping af the front bulkhead and a long feared operation can be marked off as done.

Some readers may have wondered lately "he was installing beam mounts, and all of a sudden he switches to a completely different task without finishing what he started".  The thing is, as I suddenly discovered, that in order to finish the front beam mount laminations, I had to finish taping the front bunk top. I have not done any of the top side internal panel taping.  When I was about to tape the front bunk, it was natural to do all the taping left in that area.  I will now continue to tape the bunk tops further aft in the boat and then finish the front  beam mount and front beam bulkhead taping. One side of the daggerboard case taping is also left, and that will be done when the beam mounts are finished and I can roll the hull over again.

Another thing; I have been looking for a supplier of fine multiaxial carbon fabrics for a long time, for the foils for instance, and have not been able to source what I was looking for.  Several suppliers have told me such fabrics are not made.  Today I got mail from Torkil, he found exactly what I was looking for at Formax.  Thank you Torkil!!

Saturday, January 30, 2010

Working in tight quarters

After the messy experience last night, I wondered how I was going to be able to clean up in this cramped compartment in order to be able to do further laminations.  No need to say, I was not too impressed with the quality of the tapes I had made last work night.  I ended up buying the "electrical finger" in the picture below and a few new bits for my straight and angled compressed air mini grinders


After extensive testing of the new equipment, a few f-words and a lot of carbon fibres stuck in my fingers, this is what the forward tape looked like:

And the aft part of the compartment:

The front bulkhead is at this point glued in at the lower third or so, using heavy compression to ensure good bonding in the area mentioned in the last post.  I found it necessary to have better support in the upper part before taping the rest of the front side of the bulkhead as this is partly a "not to be seen without a mirror" taping job. So I prepared the aft side of the bulkhead for taping. This area is huge compared to the front side of this bulkhead, but it still feels quite confined, rolling from side to side and partly supine to reach all the areas.

However, I was able to do some quality taping here. Also, extra reinforcements to the trailer U-bolt area and the front part of the front bunk top was taped in the same session.  My hair is so full of epoxy though, that I have to make an appointment with Helge, my drummer and hairdresser of choice, to fix it.

Then I made another shot on the extremely tight front end of bow web to hull tape, this time using pre wetted tape with peel ply attached manoeuvred into position using a thin piece of foam (no traditional tools such as fingers fit in here).  I was quite happy with the result and think I have managed to make this as strong as the designer can possibly have expected home builders to achieve.

Then I double taped the last piece of bow web to the front bulkhead, this being the roomiest corner of this compartment, it was almost like a walk in the park compared to the other taping.  I didn't peel ply though, it is most tempting to leave everything untouched when it lies flat and not risk to mess it all up again....

This leaves only the front side of the front bulkhead from bow web level and up to be taped the next time I go building, and I have dreaded for this for several months?

Finishing the internal bow area, finally started

I have not been looking forward to this job.  All the time since Jim's awful but correct comments on this post I've been looking for a suitable manner to solve this problem in a structurally sound way without having to dig out everything and then go on with a close to impossible laminating job with uncertain outcome.  Given Jim's comments on how tricky this is, and I totally believe, I was looking for a better way to get a good bond between the bow web, tape and the bulkhead.  My solution was like this (forgot to put the hull in the drawing, you'll just have to imagine):

I laminated the carbon, put the HD inserts in, and placed the bulkhead with a generous layer of micro fibre thickened epoxy on the surface in place.  Then mounted a compression system to keep the bulkhead firmly pressed against the bow web while curing.  I'm not sure this is actually better, but I'm sure this was the good part of what I was able to do that night.  The forward taping between the bow web and the hull was extremely difficult, and I was just not able to place the staggered tapes the way I wanted.  Most of it is where it should be, but there certainly is something to clean up 'til next time...

Port aft beam mount laminated

I also got the port side aft beam mount laminated.  This time a little bit faster, as one tends to get better at doing things when repeated.  (Which means I would probably be able to build an F-22 quite a bit faster if I started over again now.  Which I will definitely not do, but I must admit that I already have started to think about an F32SRX some time in the future....).  New to this side is the clamp on the flat area extension, as I saw imperfections on the other side here due to phenomena described by Isaac Newton centuries ago (it has to be your own mistake until you actually learn something, huh?).  The diagonal brace is just to straighten up the upper folding strut slot, as with this particular beam mount it seemed to want to be very roomy.

The mould was successfully removed and the aft coaming and recess laminate trimmed after this picture was taken.

Flerskrog Trøndelag - board meeting

Last Wednesday, the board of the Norwegian multihull association's northern fraction - Flerskrog Trøndelag - had a meeting in Levanger.  The members of the board met in the workshop to inspect the quality of my work and the progress.  My work so far was approved and good wishes for the rest of the project was offered from Torkil (Corsair 24), Trond Are (TRT 30?) and Arnt (Chairman), all of them experienced multihull builders and sailors.  This was indeed a big relief!;-)

I am also modifying an Eee for a friend that helped me recover a lot of lost Christmas family pictures from a bad SD-card in the family camera.

I might have to make myself one of these as well, to run navigation software (there are somewhere around 200.000 islands along the coast here, and a few of them are under water...), and maybe a music library for slow hours in anchorage...

Friday, January 29, 2010

Aft starboard beam mount taped in

I finally finished the aft beam mount moulds last week. Attached with self tapping screws at the lower end, and screws into the hull side at the gunwale.

Close up of mould.  Every corners between mould and hull or bulkhead to be filled with putty to nice round corners before taping.

All the fabric and UD reinforcements in place.  No way to vacuum this so it is a meticulous job to get everything nice and tight in every corner.

Detail of the upper folding strut bolt hole area with GRP doubler plate taped in.

The outside after removal of mould.

Friday, January 15, 2010

Recess moulds

Somehow, I'm able to spend considerable amount of time on these moulds.  They each consists of five parts cut from 19mm MDF,  using a full size pattern which suggests larger moulds than the holes they are supposed to fit into.  Besides trimming in order to fit they also have to be trimmed and bevelled to fit the curved part of the beam mounts.  Then joined in a way that allows removal after laminating without cutting up the boat.  Then you just have to round the corners, apply releasable surface and find a way to fix them in place and - voila!  Hope to be ready for more laminations real soon.  I'm working on the four mounts more or less simultaneously, here showing the exterior of the aft port mould temporarily fitted using clamps and a spacer:

And the inside of the same, I have not fitted the small piece covering the inside of the "arm".  It is trimmed to fit, but I haven't figured out exactly how to fix that part in place, probably I'll try to just tape it in place with packaging tape and maybe some duct tape on the outside.

Thursday, January 14, 2010

Beam mount taping started

The beam mounts will have to handle really heavy loads, according to the designer up to 4500 kg. Hence, he has done a lot of engineering to make sure they handle those loads.  This means that several reinforcements along load paths have to be laminated accurately and with care.  I have laminated some of the compression load reinforcements so far.  The need of making several moulds in the process means that this takes some time to do.  The newer version beam mounts are made in a way so fewer of simpler moulds have to be used.  This first picture shows the mould for the lower folding strut anchor flange provided with the beam mounts from Farrier Marine in place, and the flange laminated inside.  Just above the "arm", the exterior of the compression pad area is visible.

The first step of the inside laminations of the same area is showed here, opposite side.  This consists of several layers of bi-directional and uni-directional fibres. The area is formed against an outside mould made from full size patterns.

The rear lower folding strut bolting area after trimming flush with the hull:

Compression load path reinforcements added to the rear beam mount:

Last picture today showing port forward beam mount after trimming.  I have spent a few hours making moulds for the hull recesses surrounding the beam mounts, and still need a couple of hours to have them ready and in place.  Then the hull will be closed and the mounts further laminated on the inside, adding several more reinforcements.  It's a lot of work, but I really enjoy effectuating the fine engineering, and it will indeed be very strong and stiff.  Thinking of how Frimann is made, and the fact that she still sails after more than 35 years, makes me laugh from time to time.  This is a totally different story, I suspect this boat will survive anything.

Sunday, January 10, 2010

Beam mounts in the hull

I got all four beam mounts tacked in.  I was very particular on getting the height and lateral placement correct but found that the bulkheads was so correct placed in the first place, that I didn't bother to check the vertical angle and just tacked the mounts firmly to the bulkhead.  The result is almost perfect.Phone camera picture showing aft side of starboard front beam mount tacked to the bulkhead:

Port front beam mount looking aft.

Port front beam mount from the outside.  Note there is no forward lower folding strut flange as seen in blogs from earlier builders like Menno and Jay.  Farrier is developing his design, and I got a middle stage in the beam mount development, now they are even easier to install. 

Now, using the lower folding strut bracket mould provided with the beam mount, I prepared to laminate the aft forward lower beam mount bracket.  This was a good time to adjust the one or so degree vertical misalignment, using a clamp between hull and mould.  I filled the gap between mould and hull with foam from the outside and filled and rounded transitions with epoxy/micro-balloons/silica from the inside. 

Then laminated the lower strut mounting flanges as per plan, using carbon rather than glass (same fabric weights), so they should be very beefy.

Cockpit view:

Thursday, January 07, 2010


It's not hard, but it does take time to trim and adjust everything in order to achieve exact alignment of the beam mounts, much as I have to go in and out of the boat all the time when removing the beam mounts for further trimming.  I guess I was 40 times in and out of the boat tonight.  However, everything is lined up correctly now and I'm ready to mix up some epoxy and stick them in place the next time.

Aft beam mounts with alignment jig:

Front beam mounts with alignment jig:

External view of front port beam mount and alignment jig:

Monday, January 04, 2010

Trial fitting beam mounts

I got the starboard side cutouts done today and was able to start trial fitting the aft beam mounts.  It seems there will be minor trimming of the beam bulkhead cuts needed before installation.  Picture showing aft beam mounts in place, held by beam mount alignment jig.  Hole in hull and bulkhead for starboard front beam mount visible in the background

Sunday, January 03, 2010

Decent start on a new year

I have been able to make a decent start on this year, putting in a couple of working nights already preparing for the beam mount installations.  Only cell-phone built in camera picture quality however, as my camera died in the preparations to the last posting.

First, I had to level the boat in fore and aft and athwartships directions.  I cut my supports to keep the waterline rather than the gunwale line level, so I had to shim up the aft support.  First, to establish the exact position of the gunwale line at the beam bulkheads, I cut holes in the hull at those positions, as much energy was put in to achieve exact positioning of the beam bulkheads and thus their gunwale mark would be the best points to use in my boat.

Then, using extensions out trough these openings and a standard leveller inside to control athwartship alignment, I used a laser leveller to establish exact fore and aft alignment.  Packed up as requires as shown in the next picture.  Then I used a cardboard full size template for the cutout that I made from measures in the plan book, had a single light source several meters away and in combination with the laser leveller transferred the shape to the hull.  I used my oscillating saw to make small cuts each side of the bulkhead to control position of the pattern.  Then cut.

I still wonder about the window, as it seems to have come too close to the front beam mount, even though I am certain that I placed it to the best of my abilities according to plans.  Hmm.

Then I had to laminate the top flange extensions to the aft beam mounts.  This picture showing the beam mounts clamped to a "double mould plate":

And after the mould was removed:

I also had to make up the beam mount alignment jigs.  I cut them from MDF.  Used Guttorm's drill press to make the 3/4" beam mount location holes with a hole saw. 

At last the port side cutouts finished.  I dry fitted the beam mounts, everything seems to fit very well.  Tomorrow I'm going skiing with my son.