Unzipped and reason for satisfaction

Again an excellent result with perfect quality.

Another Milestone

I can say I now have a lot of experience with making airtight vacuum bags. As a matter of fact, within this project this is big hull vacuum bag number 9 and I thought it would be a piece of cake. After all, it is not just a vulnerable foam hull but a foam hull with an airtight internal laminate. And the joins of the Port and Starboard halves are covered with a glass tape. So no worries about air tightness. I thought ……..

After some more changes in the bag and improvements of the hull integrity in the past two weeks it had to happen.

Last weekend, despite the fact the vacuum bag was still not perfect the infusion started at 3.00 PM in the afternoon. There were a few precautions taken to be able to solve possible problems during the infusion and this has worked out satisfactorily. Only the end counts and despite the troublesome preparations it was again a success, a big relief and another milestone in the project. After a evening and night watch during the cure of the resin I went home at 5.00 AM the next morning, tired but with a good and happy feeling.

Click in the video to see how it went.

Furthermore I made a new photo galery in www.fram.nl with the flow prediction simulation and photo’s of the resin infusion process. Please click here or in the simulation image below.

Green boat.

Well, I now have a green boat, but not because of the curing epoxy, but it is still pristine resin distribution mesh behind a floppy vacuum bag.

Long story short, for the first time in my project the vacuum infusion failed, or better said, I could not run the infusion because of two persistent leaks from the inside in the aft beam area. But don’t worry, it appears to be not a big deal, it only causes slight delay.

It has been a looong day that started very hopefully:

Thursday January 5

04.00 AM
There is a violent storm going on and some areas in The Netherlands are fighting against a extremely high water level, the quay on our garden is flooded and my car alarm woke me up. The storm activated the motion sensor of the alarm system in the car. O well, it will be a busy day today, so better get up early.

04.15 AM
I receive an email of Arjen Korevaar of www.Polyworx.com containing the infusion strategy and simulation. He  worked all night to design a perfect but simple infusion strategy. This comes just in time for me to translate this into the dimensions of the runners. It shows a further development of the strategies I have used so far. Yesterday evening I prepared a fore and aft pleat in the resin distribution mesh for the vacuum line on top of the hull, but that was too premature. In this new strategy there are only some single venting ports, just ingenious.

05.00 AM
It is still no winter and the heater is able to heat the workshop to a level of about  20ºC. Yesterday I’ve put the resin in the canteen with the heater high at a temperature of about  23ºC. But before going to work on Fram I have to finish some business things at the office.

The planning for today is fixing the resin distribution mesh, the resin feeder lines, the venting ports, the vacuum bag and putting the whole hull under vacuum. I prefer to let the vacuum alone during the night from Thursday to Friday. The vacuum infusion is planned tomorrow Friday 10.00 AM. and I will be assisted by some helpers including Arjen.

But it went different.

2.00 PM
Still busy with the green resin distribution mesh. I still have to buy some PVC parts for the resin traps, 1″ tube and two valves for the resin feeding line.  A colleague of mine was kind enough to do that for me.

5.00 PM
It looks to become late this evening, so I phone my wife that she don’t have to count on me for supper.

9.45 PM
At 10 PM , the building alarm must be enabled and I phone the security company that enabling the alarm is not possible because I’m still at work. I also phone my wife again saying it will be very late tonight and she don’t have to wait for me.

D-Day, Friday January 6

1.00 AM
Yesterday I tested cheap insulation foam to see if it was not eaten up by epoxy resin. That seems to be not a problem and I now cut the venting ports out of this insulation foam.

I feel annoyed because it looks that I don’t have enough time to get the hull under a vacuum for several hours.

2.00 AM
Finally the resin distribution mesh is done and all the spiral tubes are in place. I prepare two pieces 53′x10′ of vacuum film and put them together to form a 53′x20′m sized vacuum bag. That must be enough to cover the 39′ hull.

6.00 AM
In the area of the fore beams the vacuum bag is too short and need a 5′x3′ extension. The second try of this extension does the job. It looks that the vacuum bag in the area of the aft beam is just wide enough, so in that place no extensions are needed.

10.00 AM
Vacuum bag is still not closed, helpers arrive.

11.30 AM
Vacuum pump is on, but there are a lot of leakages and the vacuum bag around the aft beam flanges is too tight and still needs an extension. Arjen is doing the Port side and I’m making the Satrboard side of the bag extension. The vacuum bag begins to look as a mess, but who cares, only the result counts.1.00 PM
It appears that the plastic valves are not airtight in the closed position. These valves are a bad buy and have to be replaced by the brass ones I normally use. However, I don’t have them and make a temporary seal with some tacky tape and vacuum film.

2.00 PM
Now we are getting some vacuum. My collegue Robert turns out to be the perfect leakage seeker. With unmatched patience and accurateness the one after the another leakage is being solved by him. It turns out that there are some leakages from inside. I thought that would not be possible because the inside is covered by the internal laminate and this has been resin infused too, so this must be airtight. Unfortunately that is not the case, it appears there are some very small holes. The only explanation I can think of is the following:

The fore and aft battens were 18mm. thick,
The foam is 15mm. thick,
So a total thickness of 33mm.
The temporary screws were 30mm, so in theory there is a 3mm play above the screw point.

Now what if the screw was driven to deep in the wood with the screw point just in or above the foam surface. Apparently this has been airtight during the resin infusion of the internal laminate, but leaves a very small hole after removing the screw. This is the only explanation I can think of.

And there are some holes from the inside in the bow tube area. But that is a result of my own stupid fault as I’ve used some temporary screws there without noticing I punctured the internal laminate with them.

4.00 PM
The vacuum is still not more than about 15″Hg, caused by two leakages in the aft beam area and these seems to come from inside as well. The only way to fix that is to give the sealant tape of the vacuum bag an alternative route.

But by now a jetlag feeling is overwhelming me. The alteration of the vacuum bag and putting vacuum on again will take at least another three hours and together with the infusion and geltime requires another 14 hours of me to stay awake. Saturday and Sunday I have other (family) obligations so it is not wise to go on.

But now that I know the cause of the malfunction it is easier for now to give up.

… to be continued …

Single side infusion on a foam hull (mold)

On one of the boat building forums there was a question about the practical aspects of doing a single side infusion and where the foam hull is the airtight mold. This for sure requires a meticulous job on the foam hull, preventing any piercing by screws, or repairing these very thoroughly, and a lot of attention for the bog in the joins between the foam sheets. It is good practice to use as large as possible foam parts to minimize the amount of seams. To be sure that the joint is airtight, I treat them in four stages. The first one is widening the seam with a Dremel tool and routing a V-shape in it. Then I fill these with a thick mixture of epoxy, aerosill and microballoons, the second layer a little thinner and the final layer again a little thinner. Of course this requires extra time, but doing this well is very important for the integrity of the vacuum bag. Taking shortcuts in this phase will lead to the nightmare of not getting enough vacuum for the infusion. In that stage it is too late for making repairs and the decision has to be made to give up the infusion and to go back to the hand-lay-up job.

Of course  the single side infusion on a foam hull requires a closed cell and airtight foam. The A quality Corecell foam is a fine example of such a foam. The thickness I use is 15 mm (5/8″) Thinner will be more difficult and thicker must be easier in regards to making an airtight foam mold.

Have a look at the figures below to get an idea of the (extra) hours for making the foam hull (mold) and to infuse the internal hull laminate.

You can see there is a kind of learning curve. Only the last hull (Main hull port half) is made in the new workshop. The difference in working hours between the cramped workshop in my garage at home and the very comfortable and roomy workshop I have today is not very dramatic. All work has been done on my own. Working with two people is more efficient and I guess will save at least 25%.

This table and other statistics has been updated in this page on www.fram.nl

In the mean time I’m working hard (well, not today  to get the main hull ready for the infusion of the external laminate. I hope to be able to do this in the first week of January 2012

Merry Christmas to all !

Preparations for the construction of the beams.

For this winter I have planned to build the four beams in my garage at home. De beam molds are ready and one of the first parts I need are the upper folding strut recess sides. These are made of pre-made 4mm. thick solid laminate. For the eight pieces and some smaller doublers I vacuum infused a 4′x6′ solid laminate plate.

The low viscosity epoxy resin starts to gel after 300 minutes so there is enough time for a simple version of the infusion setup. Below three photos of the infusion, the first after 15 min, than 1 hour and the bottom one after 1.5 hour.

There are also some new photos in this galery.

Resin Infusion Workshop impressions

About RTM, VARI, SCRIMP, VIP, CVI, vacuum bagging, resin infusion, core materials, resins, gelcoat, fibres, fabrics, peelply, release film, flow media, flow channels, tacky tape, vacuum film, vacuum tubes, spiral runners, mould, mouldless, connections, staples, glue, clamps, valves, injection block, suction cup, by-pass, print through, leaks, ultrasoon leak detector, thermometer, temperature, vacuum pumps, vacuum capacity, air flow, leaks, resin trap, drop test, outgassing, absolute pressure, gauge vacuum, vacuum cleaner, barometer, mbar or “Hg, Darcy’s Law, infusion time, infusion length, viscosity, permeability, pressure difference, infusion strategies, infusion setup, race tracking, flow front, safety, post curing, test panels, flow simulation, RI starters kit, tools, tips, tricks, …….. etc.

I forgot to take more photos during the making of two 4′x8′ sandwich panels by my course participants. These photos were made right after the start of the infusion.  Both panels have a different infusion strategy, resulting in a 4 times faster infusion for the one panel compared to the other panel.

The overalll conclusion of this intersting day was that while the infusion technique is not very difficult to understand one has to do it in practice to see, feel and experience the ease of making a sandwich panel in this way. Key factor for succes is the use of the right materials and knowing the practical applications for them. The goal of this workshop was learning by doing and together with some more tips and tricks be capable to copy this in your own practice.

Thanks guys, I’ve had a nice day !

Flow simulation software.

So far I made three computer flow simulations, the inside of the floats, the outside of the floats and the inside of the main hull. Actually, the developer of the RTM-Worx flow simulation software, Arjen Korevaar of Polyworx, made them and I only did the dumb data input. Anyhow, last time was somewhere in 2007 and now I have to learn the simulation software all over again as I have forgotten all about it. However, if all goes well I must be able to convert the existing 3D model of the port main hull half into a lower (bottom) hull half and an upper (deck) hull half. Next is the input of the various fabrics attributes and then the model is ready for Arjen to determine the runner placing and sizes.

I still have two simulations to do, both outside main hull. First the bottom part and second the deck part after which the virtual boatbuilding regarding the boat hulls is finished.

In the mean time I am fairing the foam hull, filling the outside of the joins with bog and laminating extra reinforcements around the beam bulkhead flanges.

Workshop Vacuum Resin Infusion May 14 2011

Today the Dutch digital sailing magazine Zilt published an article in her 59 edition about building Fram. I think this will generate a lot of traffic to my website www.fram.nl and thus is a good opportunity to announce my intention to organize a workshop resin infusion on Saturday May 14.

In this workshop you will learn the basic principles of resin infusion and hands-on the making of a composite sandwichpanel. The cost for this workshop are € 150,– (only € 50,–if you have purchased the RI kit in the past), this includes a light lunch and the RI Starters Kit, which for this opportunity has been extended with a foam core and the needed special formulated infusion resin. There are hotels in the immediate vicinity of the workshop and I will take care for your transfer from hotel to workshop and back.

Location : Energieweg 6, 1271 ED Huizen (Netherlands)

Program:

• 10.00 am: Infusion strategies, vacuum pumps, resin trap, tubing, consumables, vacuum bag
• 12.00: Lunch
• 1.00 pm: Practical workshop with the making of a composite sandwich panel.

In between or afterwards are enough opportunities to have a look at the Fram project.

Please use the email form below to get more information.

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Understanding Vacuum

 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.

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

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.

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.

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

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.

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.

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

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 http://www.fram.nl/