Routine chores.

December 7, 2014

Making composite panels out of 1220×2440 (4’x8′)  foam sheets is an ever returning job. I make all bulkheads and interior panels always in the same way. This is the double layer vacuum infusion system where both laminates on each side of the foam core are infused simultaneously. Working alone it takes me about 3½ hours from start to finish including cutting the materials and preparing the vacuum bag.


In the above image the resin flows from left to right and is halfway the panel. This is relatively simple to do once the principles are understood. However, the devil is in the details and the best way to get it right is to buy my Vacuum Resin Infusion Starters Kit in which the procedure and required materials are fully described.

RI Starters KitBut there are more vacuum based recurring chores, for instance making rounded edges. I use a lot of them, on the outside, like the front edge of the cockpit seats in the image below, or on the edges of interior panels.


By the way, this is not the finished cockpit coaming but the flanges for the cockpit seat back. Anyhow, the rounded edge starts with a partly cut PVC pipe.


The glass fabric for the outer laminate is laid in the pipe.


From left to right, the pre cut foam strips, trapezoidal shape inside smaller than outside width, green bleeder and release film, peel ply, inside glass fabric, the pvc pipe mold,  groomed vacuum bag with one side attached to the mold and at the right two at an earlier moment made half foam tubes.


Foam strips placed with micro bog.


Now ready for the vacuum bag.


Vacuum bag almost closed. This is the tricky part because any resin on the sealant tape will spoil the fun.


Finished and under vacuum, waiting for the cure.


Detail of vacuum tube connection.


A seemingly endless series of chores

December 17, 2012

click for photo gallery

The recent months were marked by a particularly stiff continuing of not the most pleasant chores. One of them the hand-lay-up laminating the molded recesses for the deck hatches and the window rebates and then applying a vacuum bag, which is not my favourite job. This work against the resin clock requires a perfect preparation, work fast, focus on infinity, lots of disposable gloves, some sweat and a slow hardener. But it is almost done now. Only the escape hatch in the foredeck still to do, but somehow I cannot get the right specs and the delivery of the ordered hatch has been delayed.

All these small chores have to been done but are a bit tiresome. However the end is in sight and I look forward to a more visible progress.

Vacuum bagged laminate around the molded hatch recesses

December 3, 2012

Click for photo galery

I choose for a separate laminate around the molded hatch recesses and daggerboardcase opening instead of adding these layers in the vacuum infusion proces. Reason for this is that it is difficult to get the rather thick laminate in the tight corners of the molded recesses. So (for me) it is better to do this in two steps, first the extra layers with wet hand-lay-up finished with the help of the vacuum bag and second (later on) the resin infusion of the whole deck laminate. This is extra work (and time) but I want to be sure to make it structurally sound as the hatch openings are quite large holes in the deck. For these vacuum bagged layers I removed about 1mm of the foam (the bogged area in the photo) with a router to prevent to much local laminate thickness wich would require more fairing work as an unwanted result.

Obligations, having fun or building Fram

September 18, 2011

Besides all kind of obligations there were also a lot of temptations, like enjoying a holiday in Spain, or sailing with Blind Date or with Gary’s F36, or just having family fun, or …. all responsible for the slow progress lately.

And no Gary, I did not fall for your trap to buy that F27 to play with to  induce a further delay to participate in the regattas with my F39 😉

In the mean time I still manage to do some things on Fram and you can find the latest photo’s by clicking the following links:

– Sterntube, now finished with a nice shaped kevlar laminate
– Mainhull, all kinds of small jobs, like the for now finished wingnet flange

Next update is starting with the outside hull laminate (about 6 months later than planned at first 😦

Understanding Vacuum

February 2, 2011

 In the year 2000 when I started to study the possibilities for a DIY boat building project, I was a total composite greenhorn (still too much honor, I knew nothing) and there was almost no information about vacuum infusion except that it was some kind of black magic, operated behind closed doors by some very professional boat building plants.

However, vacuum resin infusion seemed to me the ultimate way of laminating a boat hull and in fact it made my single handed boatbuilding project possible without having any previous composite experience. Vacuum infusion is a defined process that not depends of my initially lack on knowledge and experience and skills for laminating big boat hulls. Now that has been said, think about the following. Vacuum bagging is much more tolerant and can operate even with a not leak proof vacuum bag and at lower vacuum rates, so must be much easier to do. However, being not a defined process, requires experience and skills in the eyes of the novice composite worker because it has to start with a hand-lay-up laminate with all the accompanying tits and bits.  Here is a link to the pro’s and con’s.

For the experienced composite worker it is a piece of cake and is the text above just BS. For the beginner in composites with a high tech composite yacht in mind, the choice for vacuum infusion is a logical one. Just acquire the knowledge and go for it ……

In the composite practice it is necessary to know a little more about the vacuum pump, the use of measuring units and to handle some pitfalls in the field of vacuum. At the start of my composite adventure I had wished there was some more composite related vacuum information available and in such a way I could understand. With vacuum resin infusion the devil is in the details and it is these details that make the difference.

Understanding Vacuum

So, also as a refresher for my own knowledge of the matter, I made a dedicated webpage about vacuum as being seen through my composite glasses (and including two ads as the tower must be kept smoking 😉

The following questions will be answered:

  • What is a vacuum ?
  • Which metric or imperial units are in use ?
  • What is the difference between gauge vacuum and absolute pressure ?
  • How about the vacuum pump, which type or size to use ?
  • Large central vacuum systems or multiple small pumps in the professional plant ?
  • Is a vacuum switch useful ?
  • How out-gassing can spoil the fun ?
  • Why test for leaks ? (includes an ad for the Resin Infusion Starters Kit)
  • Going Hi-Tech with absolute pressure ?
  • Which vacuum pump is best for the vacuum needs in composites ? (includes an ad for vacmobiles vacuum systems)

This is the link to the webpage.  Have fun in studying the information and I hope you liked it. As always I’m happy with your comments, critics and your own experiences.

Vacmobiles vacuum pump for Belgium A&B Yachts

December 29, 2010

The Fram Project is a perfect demo location for the Vacmobiles vacuum equipment. And so it went that Belgium A&B Yachts has taken over my Vacmobiles 20/2 vacuum pump for the application of vacuum infusion in their GT80 project, the construction of a 80 foot Peltzer designed stylish gentlemen’s yacht.

Vacmobiles pump transfer

I’m sure that they will have as much fun using this pump as I’ve had and I’m glad this pump continues in a serious boatbuilding project.

This transfer made it possible that, just on time for Christmas, the Santa Claus delivered the latest model vacuum pump, the Vacmobiles 20/2 Model 2010.

Vacmobiles 20/2 vacuum pump

Compared to the “old” model the new pump is fitted with a solid glass lid for the resin trap.

Solid glass cover

Accepting that the catchpot capacity in the 20/2 machine is relatively small at 2 litres (4 USpints), the new glass lid is good for peace of mind when the machine is used to infuse larger parts. In conjunction with valves or clamps in the vacuum lines to the resin trap, it is now possible to see the resin level and empty the catchpot if need be during the course of an infusion, with minimal disruption to the process if the valves/clamps are correctly sequenced.

Another enhancement is that the previously used camlock connection between the main control manifold and the resin trap has been replaced by an O-ring sealed connection, which is easier to use and seals more reliably.

O-ring connection

Further more the model 2010 has a tougher mounting for the resin trap.  The resin trap body is now supported off the main handle upright. This is a much sturdier design and the bottom cap latches cannot be strained by impacts on the trap body.

Resin trap

Going now serious in vacuum Santa Claus also included an absolute pressure gauge in the Vacmobiles package. More about this later.

Absolute pressure gauge

So with this now up-to-date vacuum equipment I’m completely ready for the New Year. If you want to see this vacuum equipment in action please contact me through the email link at

Stern tube installation.

December 24, 2010

I finally made a decision about what kind of propeller shaft support bracket to choose. The plans calls for the fin or P type but in my view these have some disadvantages. First, it is not made of composite but of steel, bronze or brass . This means a different material that sticks out of the hull with risk of leakage as it is a subject for high forces. To me it also looks quite vulnerable but it has to withstand ropes or netting that can be caught by the propeller but also a stone/rock on the wrong place when drying out.

A  more solid construction is possible with the reinforcement type shaft support, the skeg with build in stern tube. Advantage it is it can be made as a whole with the hull (all composite) but disadvantage is some more drag, more difficult to make and some extra facilities for the water lubrication. I think I can minimize the drag disadvantage by making the skeg as small and thin as possible with a carbon plate as base. The following picture shows the general idea.

Click for photo gallery

Click in the picture for the photo gallery.

The engine page has been updated too and there you can find two photo’s of what can happen with a P- style shaft support bracket when catching a lobster pot rope.

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