Insufficient attention in the class ?

First of all, thanks to the other F36 / F39 builders who have gone through the same process and published their learned lessons. I was convinced that I would not step in the same traps.

Now I know better. Pride comes before the fall.

Lessons learned, stay sharp also at the end of a long building project.

Using the outer ends of the beams as a mold for making the beam sleeves is not very difficult, I made them with vacuum bagging, but releasing them from the beam outer end is another story. I was warned by the experience of other builders who had great difficulties with releasing the sleeves. This helps me a lot executing a well proven releasing procedure to lever off the beam bolt. So I made some wooden beams and placed them over the beam bolt nut with a big washer in between. Connection with the sleeve is with two layers of  (left over)  carbon UD. I prepared the beam outer ends with 5 layers of a mold release wax. I have used this stuff before and had not difficulties with it ……

However, somewhere in this process or in my thinking I made a big mistake and my worst nightmare has become true. The sleeves did not want to loosen. Even with a very brute force they are not prepared to separate from the beam. Of course there is always a plan B, but damn, this feels like a loss. I ended up with making a cut in the underside of the sleeve giving space for some wedges. All four sleeves were more or less glued to the beam at the same spot, the edge between underside and outer end. Coincidence ? or has anyone a smart conclusion …

In retrospect, the preparation with the mold release wax was not good enough. Did I forget this edge ? did I forget it five times ! (I’m not surprised at anything) or should I have used a PVA release agent in addition to the wax. Or using packaging tape in addition to the other mold release stuff which gives then two chances as the tape itself is also able to release. I don’t know. What I do know is that the approach of the four beams at the same time did not prove very clever for such a delicate work. There is no way to adjust the technique and make improvements in the meantime.

What I do know now is that plan B is not a big deal and is a good solution for quick builders. Thus not worth a nightmare 😉

Pffff, a huge relief.

More photo’s of this adventure are here.

Post-curing the beams.

The slow hardener of Ampreg 21, which I used to build the full carbon beams, likes to be post-cured at a moderately elevated temperature of 50 degrees Celsius during 16 hours. To do this I have built an insulated box heated by a simple blow heater.

Start making the box and support for the four beams.

Positioning the beams.

Finishing the box.

Post-curing in progress.

YES! The Beams are finished.

At least structural, which is a great relief. Since my last post in May I’ve spent 570 hours in building these full carbon things. Including the build hours  before May I’ve spent a total of 630 in building the Beams. That is besides my day job.

That being said, I had to introduce myself to my wife again 😉

So, I’m in a hurry because the launch of Fram is now coming seriously in sight.

However, the good progress of construction remains bad for the updates of this website. Hope you understand that.

Have a look at the photo galleries, Beams Interior and Beams Exterior

 

First beam interior finished

First of all my apologies for my silence here lately. I am just too busy with getting my boat finished to publish regular updates.

However, last week I reached another milestone. The first beam interior has been finished and the second is also progressing very well. That sounds not very spectacular but for me it is a big step forward as I was very much  looking against it.

The photo gallery of the beam interior has been updated with a lot of new photos so please have a look.

Dangerous mood

After such a long construction period one must be careful not to make any shortcuts. It remains necessary to keep thinking about the things you do. So, what is wrong in this picture ?

This is the vacuum bag around the final laminate of one of the carbon beam anchors. Rule nr. 1 in vacuum bagging is to put no other parts in the bag except the epoxy laminate. And certainly not a rotatable shaft and bearings that needs to be dismantled again. What a stupid mistake. The epoxy has glued everything firmly together. D!#$* it was a hell of a job and only with brute force, an angle grinder and a hot gas flame the temporary shaft gave up his firmly connection with the carbon anchors.

The image below shows how it has to be done and this experience has put me back on earth again.

Anyhow, at the end I have 4 beam anchor assembly’s ready to put in the beams. And yes, that means I’ve finally started the build of the beams. More about that later.

Daggerboard construction

For a long time I thought I was going to make the daggerboard in the same way as the rudder. So, with the aid of a mold. To which I have just postponed that for some reason. But at the finish of the main hull the appropriate daggerbord case slot must have been created. A good reason at last to make that daggerboard.

I made it almost according to the plans, so with a Western Red Cedar wooden core. But to prevent this core against water penetration in case of a collision with an UFO, or hitting the ground, I made two changes to the plans. First a leading edge with a high density glass fiber core behind, instead of the wood, and second a bottom part with a foam core. In addition to these changes and for structural reason I replaced the wooden core in the leading edge by a glass fiber core.

Photo’s are better than explaining by words. You can find them here.

Enjoy the animated gif of the infusion of the daggerboard.

Rudder construction is nearing completion

With the making of the steering arm the rudder construction is nearing its completion. Click here or in the photo below to open the photo gallery of the construction.

Rudder construction.

After the making of the mold for the rudder blade it is not a lot of extra work to make two rudder blades, as I want an extra one in case of a fatal rudder damage. In fact, I make two complete rudder systems, one spare system in case of a fatal rudder damage.

Next is to decide which rudder system to make. Designer Ian Farrier provides various options for the rudder system.

The main choice is between the underslung rudder (not shown in the drawing) and the daggerboard style rudder. I prefer the latter as this system gives a better steering control for getting in and out shallow waters as it can be raised up and down.

The daggerboard style rudder system comes in three variations, in this drawing called A, B and C. The difference is in the manner in which the rudder blade kicks back should any object be struck.

The rudder option C with the hinged rudder box is only suitable for a steering system with cables and therefore not suitable for me because it does not fit in my chosen transmission steering system. After all, this system requires a fixed connection to the steering arm of which position is not affected by a pivoting movement.

The rudder option B is my preferred rudder system and consists of a two-piece pivoting case and sleeve. Should any object be struck or the rudderblade hits the bottom, the aluminum rudder lock bar will break, allowing the rudder to kick back preventing any more serious damage.

Rudder option A is much simpler but will not kick back should any object be struck. However, the case should split apart down the aft edge (with aluminum bolts sheering) to allow rudder blade to kick back without any damage to the transom. But some damage to the rudder case is likely to occur, which I can confirm from my own experience whith such a system on a F33. Due to the simpler construction this will become my backup and emergency system.

Click in the above picture or here for the photo gallery of the making of the rudder sleeve and case.

Finished rudder blade.

Update with some new photos about the finishing of the rudder blade in the gallery of the rudder construction.

First rudder blade half

The first two rudder blade halves are out of the mold. Click in the image above or here to see the photo gallery of the step by step process of making these blades.