Saturday, 2 June 2012

The Didi Retro 29 update

We now have the French marine ply at the CNC shop, plus the required cut files, so we can start on that side when the customer is ready for his kit. This will be in a week or so, as his builder has still to complete the garage extension the boat will be built in.

Dudley Dix supplied me with a 3D image he has placed on U Tube, click on the blue link to see it. .

Or you can also find it in the original blog below, with the report by Justin Phillips on the new design.

Soon to be built here in Hout Bay, South Africa.


Friday, 1 June 2012

Testing times for marine outboards

Justin and I decided to do a back to back outboard test using a broard range of old and new motors, the older one is fifty one (51) years old, the newer one about five or six years old?

The motors are a 3.5hp British Seagull, a 4.5 British Seagull, a 5hp Yamaha and a 2.5 Mercury, which will perform best on the same dinghy in the same time period?

 A winters day in South Africa, Justin is ready to be a judge in our very own PBO (practical boat owner) style outboard test.

The venue was Hout Bay Harbour,  the time around 11am, Justin  had brought his 15ft twin hulled GRP dinghy, his 5hp Yamaha was already fixed to the dinghy transom, It has just returned from a full service by the Anchor Boat Shop.

This class of dinghy is well suited to the test, as with two hulls its really stable. The 3.5hp Seagull is on the left and the 4.5hp Seagull on the right.

A similar Mercury 2.5hp to the one used, we found some interesting but not surprising results, the Yamaha 5hp was used first as it was on the boat already. For communication we used a pair of Icom M71 VHF handheld radios on a low setting, plus Justins Garmin V GPS, we then tried each engine to see what kind of top speed we could get?


The actual Mercury 2.5hp we tested was bought some while back in near new condition, I would guess its around ten years old but has very few hours on it. The performance was impressive from such a small motor.

Justin on our return to the slip, we are now two up and loaded with the four outboards, spare fuel and safety gear, this includes the 5hp Yamaha that is pushing us. With the boat empty and running on the far side of the harbour I recorded a speed at 10.1 knots. With that motor off and the smaller Mercury 2.5 hp fitted,  I saw a top speed of 5.6 knots, with just half the power, thats not a bad speed. The speed at a quarter half throttle was still around 4.3 knots.

The test with the two Seagulls prooved little, both had problems running at even half speed, we have been told by John of to check the Villiers carb jets. One was found to be quite blocked, now clean the motor runs well. The other Seagull is now on the bench and when thats running well we will continue the test, so keep an eye open for that blog.

Hout Bay Harbour is a part of the Table Mountain, Karbonkleberg nature conservation zone.

All pictures taken by R McBride, using a Canon G11 digital camera on an auto setting.

My thanks to Justin for the supply of his dinghy, outboard, GPS and for working out how
to do the U Tube from the video he made.


10/06/2012 , we have all motors now running well, Justin will return with his dinghy again and we will complete the test, we just need that same calm weather!

Thursday, 31 May 2012

Teak and Holly boat flooring

I say Teak and Holly but its really Teak and White Ash, which is much more suitable for the job at hand. We will soon offer this ex stock or to special order by air freight, rolled in a cardboard tube.

The sheet is in veneer form and around 1mm thick, its a wood on wood product with a super thin bonding paper in between, thats not visible to the naked eye.

The sheet size is 2440mm x 1220mm ,we can recomend which twin pack lacquers will be the best to use. Remember, with wood flooring you are always walking on the clear finish and never the wood!

How good is that.

Update, the factory is running a test order with phenolic backer, this then gives us a very firm sheet similar to a sheet of Formica, easy to handle and a lot more stable.


Can your digital camera do forty million frames a second?

BBC World Service radio, frequency 12.095khz African Service.

I was listening to an Indian proffesor discusing the last twenty years of his work. I had missed the start of the program but could still grasp a part of what he was saying. What caught my attention was the fact they can record the work as its happening at 40,000,000 pictures per second!

As you can see, there is a central “barrel” portion, and two “forward disks”. The detectors themselves are rectangular, and, as the name implies, segmented into very small pixels about a tenth of a millimeter in size. That’s a lot larger than the pixel size in your digital camera. But this detector can take 40 million pictures a second, keeping the interesting ones and discarding the vast majority.

If we could strip away all the support frames, cooling, electronics, etc. from the pixel detectors, leaving only the detectors themselves, they would have an arrangement sort of like the diagram above.
What I ask can we do with 40 million pictures a second!  thats some camera.

Inside the machine, it passes under a few countries I believe.
The heart of the pixel detector is the readout chip, a silicon microchip specifically designed and fabricated for this detector, in this experiment. The effort to develop the readout chip was led by Roland Horisberger of the Paul Sherer Institut in Villigen, Switzerland. Each chip has over 4000 input channels arranged in a grid; each channel is bump-bonded to a sensor channel. The sensors are also very thin silicon wafers with one surface segmented into pixels. Each pixel channel can sense when a certain minimum amount of charge has been deposited by a passing charged particle, digitizes and time-stamps it, and sends it out onto the readout bus when a trigger signal matching the time stamp is received. All the thousands of readout chips in the detector do this in parallel, ultimately sending the torrent of data out on optical fibers to data acquisition electronics modules in the service cavern adjacent to the main detector cavern.
The PSI group built the central barrel portion of the CMS pixel detector, and the forward disks, which are somewhat more complicated mechanically, were built by a consortium of US universities and Fermilab. The forward disk detectors were assembled at Fermilab and then transported to CERN for final assembly, testing, and now installation.
Read the link for more on this story.
A comment in from a regular blog viewer in England.

That's all very interesting stuff but it must be costing a fortune and is completely unproductive as far as income, it just consumes money. The original idea of such a collider was to learn how to produce atomic fusion, we now have atomic fishion that power out nuke stations but this is a dirty business producing active waste that lasts thousands of years. If they could crack the fusion problem it would lead to unlimited power without the active waste problem so I wonder what they are messing about with pixel detectors for unless its to find out how to get the particles to collide in such mass that they get fusion? It's all terribly technical and employs thousands of boffin's.


Wednesday, 30 May 2012

The adjustment of points on a 4.5hp British Seagull

You can bring your Seagull to me to have it serviced, I now have the back up of a spares supplier, plus the workshop manual. The pictures are of a WSPC **** JJ6 model made in 1976.

The points are accessed by the removal of the top cover of the magneto.

The points are to be found at the end of the spring, set them to 0.20" or  0.50mm.

This is the coil that is charged by the revolving magnets of the magneto. See how new it still looks but the engine is a 1976 model, so all  of 36 years old!

Note, the timing is fixed, only the plug and points can be adjusted. If you change either setting, the timing will advance or retard, depending what you have done.


Hands on boat building by George Buehler

I have never met George but we get on well enough by email and he sent me his must read book Buehlers Backyard Boatbuilding, this is a book for people like me.
Its not technical at all, just down to earth get out your old cloths and tools, then build yourself a boat. George has an ethic which says why use the best and new materials when we can build with recycled or a lower grade material.

From our side we looked at the timber required for the boats keel and hull frames, chosing to use local SA Pine, (radiata species) it was selected and twice treated with a CCA (copper) vacume application. This worked rather well, it saved a stack and we had prime timber to work with.

We recently discussed a much larger boat to the same design, done as a kit set here with all its materials, keel, stem, frames and rudder, we would send the kit boat to the client in Brasil.

Click on the page, it should open large enough to read it? otherwise I can send the scans to you by email.

About May 1999 I was contacted by a guy living in Zambia, he asked  would I build him a 38ft Diesel Duck in wood he asked? Seems he had discovered the TBA and when he asked around, some members recomended myself?

His wife came to see me and we discussed the venture, soon we had the plans and Georges building book, the pricing was done and an agreement made. I am not sure how Neil Rusch, the then editor of SA Yachting came into the picture but he had also done a story on a 50ft version which had been built in South Africa by a husband and wife team.

In the case of the 38ft Diesel Duck and in wood, our build was to be the very first in wood, all the others being made in steel but I have done this process before, use the designers steel boat plans and build a wood/epoxy boat.

When Neil arrived I was setting out in my small factory in Paarden Eiland, I later moved to a much larger shed in Cape Town Harbour to build the actual boat. Neil and I discussed the process and who else could use what I was doing? Costs were low, really low, using local materials for the frames and the first stage planking, then WBP plys, plus epoxies, we still had a materials cost under R80,000, just U$10,000 at todays exchange rate?

This boat was the very start of as this was our first kit, the idea was to sell to fishing communities so that they could self build, their labour was free, the kit low cost and the boat very sea worthy.

The boat was launched and last I saw her was in FBYC waters, her name is Miss Pickles!

The story in more detail is here.


Tuesday, 29 May 2012

Teak wood for sale

We have some of the best FEQ (first european quality)  in stock right now and in Cape Town. Bought to a higher grade and not down to a lower price, we also opted to have it kiln dried with lengths to 2.9mtrs x 50mm thick to 230mm wide.

We have about a half cubic meter, you will need more to do a laid teak deck like the one in the picture!  The boat was to be found at the Antigua Classic Regtta 2012 recently, I was sent the picture but with no name to who took it.


Wanted, the Sansui AU 555a amplifier

This was one of the best amplifiers at the time, I sold the contents of my appartment and the lease agreement to go off sailing back in 1977, I am still playing my vinyl  records using a Yamaha turntable and a Sony multifunction radio. A dedicated amplifier would be best.

Does anyone have a Sansui AU 555a amplifier for me. Naturally it must be in good working condition.

I am in Hout Bay, Cape Town, South Africa, contact me if you can help.


The info on the set follows:

The Integrated Amplifier of PB series which upgraded AU-555 and renewed the description and the design.

The whole page consists of silicon transistors.

The SEPP-ITL-OTL scheme of the pure complimentary darlington circuit which adopted the silicon transistor as the power transistor is adopted.

In order that an electrolytic capacitor may avoid the ill effect which it has on a music signal, as much as possible, using a hardwired-connection circuitry, a capacitor is lessened, and a required fraction makes a circuit impedance high and is using the Mylar capacitor.

Moreover, electrolysis connected the Mylar capacitor to the surely required fraction in parallel, and has improved the high region property.

The triple tone control of Bass, Midrange, and Treble is carried.

Moreover, since it is an it1 step type control, a special NetWare program and a more exact correction of a room acoustic can be performed.

Basics on the Sansui 555 au  amplifier.

Power output: 50 watts per channel into 8 ohms

Harmonic distortion: less than 0.5%
Frequency response: 20 to 80,000Hz
Channel separation: 50dB
Output impedance: 4 to 16 ohms
Dimensions: 15 x 4 3/8 x 10 7/8"

Weight: 17.4ibs

Update, December 7th 2012

This far I have had two replies, one was in South Africa, that was so expensive it was just not acceptable, another comes from Brasil, a nice one owner amp but again the cost to ship will just price it out of where I want to be!


Which is the right marine 2 stroke oil?

My start with two stroke engines as many years ago, it was a 2hp Seagull and that ended up as a swop for a rubber duck dinghy in Rio do Janerio, we needed to get ashore, having an outboard and no dinghy was not going to work?

The picture shows two things, the mix in the plastic rectangular container is just one month old, it was in a brass tank of a 3.5hp British Seagull that one month. When it went into the tank it looked like the freshly mixed fuel in the plastic 5ltr container which was mixed the day before.

In years gone by and with the old style (real) petrol such degrade was not an issue, we could mix and store for ages, is this not the case now?

The mix shown in the open container has gone a dark brown, why? I used some old Mobil marine grade 2 stroke oil I had, its about twenty years old, does it go off?

A friend has recomended I use Shell Nautilus premium outboard  oil, as he has mixed that with unleaded petrol and stored it for many months with out any degrade.

Shell Nautilus is dyed green, so matches the unleaded fuel a little, this helps with later identification of the mixture, the reverse side of the five litre container has the 10:1 British Seagull ratio and also the date I mixed it writen in a black koki pen.
I will let you know how I get on with this Shell oil.


Monday, 28 May 2012

Fishing in Hout Bays local waters

It is not often that my work takes me along one of the capes best scenic drives and on such a perfect day. I was taking a Cape Henry 21 drop keel to the CNC shop, as we will do the packing there.

The Sentinal as seen from Chapmans Peak drive, what a place to live and sail!

Looking down I saw these two trawlers, I thought they  may be pair trawling, as they were so close to each other.

They are in fact inside Chapmans Bay, Hout Bay is to your right.

Fishing here means its very cost effective, as the off  loading port is just out of sight and no more than five miles distant.

On my return it was easy to see they were tending their own nets.

Ring them in and suck them out.

All pictures by R McBride using a Canon G11 on an auto setting with tele focus on some shots. Pictures will enlarge if you click on them.


Mc Bride mum and dad do the TBA regatta

This was a nice flat and calm Easter weekend, enough breeze to sail when it mattered but really fine weather for people like my folks.

Doreen and Rob McBride in Table Bay, the boat is the Endurance 37 named Ocean Cloud, we are just off Granger Bay.


Sunday, 27 May 2012

Are you using LSD?

LSD has been used for some while I am told, news to me really and I have never touched the stuff!

LSD? means Low Sulpher Diesel which now has a low sulpher content of just 50 ppm, which is short for parts per million. The old stuff has a whopping 500 ppm by the way.

I was at the local Shell petrol staion buying unleaded fuel for a back to back outboard test, soon to be published here as a U Tube clip, so keep looking in. We will test a fifty one year old 3.5hp British Seagull outboard against a much newer Yamaha 5hp and a Mercury 2.5hp, plus a British Seagull 4.5hp motor to get a decent cross reference.

LSD? should I change to it?

Justin dug around and found this for starters.

Roy – there alerts for leaking seals, fuel pump problems, and slightly reduced lubricity for LSD with older engines. Yanmar recommends an additive for some of this. While its not a big issue – its not a pure win going to LSD on marine engines yet. I believe from 2014 new marine diesels will be designed for LSD

More on this just now.

Taken from this link

Many thanks!

 Will my old diesel engines run on ultra-low sulfur diesel?
Older vehicles and equipment will run on ultra-low sulfur diesel and will experience a small reduction in particulate matter. Operators of old diesel engines may want to replace gaskets and seals as very old gaskets shrink and leak when running on low sulfur fuels. However, EPA and the Engine Manufacturers Association do not anticipate problems burning ultra-low sulfur diesel in old engines. On the other hand, vehicles and equipment outfitted with new emission control technology ( e.g. diesel vehicles with 2007 model year and later engines can fail if run on the high sulfur diesel fuel). ends.

For myself, I will continue with the old diesel fuel, its best for the engine and its also a lower cost!