Building a Mini Max hydroplane

Readers with a good memory might be able to remember that two years ago Gustav, Asger and I constructed a Mini Max hydroplane in the summer. 

The plan was always to make another one, so each of the boys had their own. 

And last year we completed the second one. 

The construction is really simple, but the boat just looks nice and is a fun project to build. 

Asger decided on the paint scheme for this one and he was determined that it should just be a blazing orange on the top and white inside and on the bottom. 

I had purchased an outboard motor from one of my friends, and we decided to try and make a steering wheel for it so it felt a bit more like a racing boat.

Near our summerhouse, there is an old shop that has been under the same ownership since 1970. They carry basically everything. Form tape recorders (though not modern anymore) to regular dairy products and household items.

The shop is well worth visiting just to see the enormous amounts of weird old stuff for sale. 

Prime examples are: blades for scythes size No 4, made in the Soviet Union, 

400 or so pairs of old rubber boots that are frequently treated with a bit of silicone oil to prevent them from cracking while still in the store. 

And the list goes on!

The orange paint that the boat is painted with is bought at that store. It is an old can since there is no MAL code on it (mandatory from some time in the 1980'ies in Denmark I think)

The colour agent is lead chromate which also sort of fell out of favour a couple of years ago. But that sort of stuff is still available on the shelves of this shop.

We will try to get it stored at the summer house, since it is a lot nearer to the water. Then there is a chance of it to see more action.

 

Gustav testing the steering mechanism.

Asger painting the hull.

Completed paint job.

Statsraad Lehmkuhl details 3, the Boston Teapot Trophy

The Boston Teapot Trophy is a trophy that is awarded to the sail ship that covers the greatest distance over the course of 124 hours.
Why they have chosen that time frame I have no idea of, but as it happens, Statsraad Lehmkuhl has won the trophy 8 times.

Our ship is the current holder of the trophy, and due to that, the actual trophy is sitting on a shelf in the CEO's office.

The trophy itself is a copy of a teapot which was made by Paul Revere (yes, that Paul Revere!). Whenever we hold a meeting in the CEO's room, I find myself drawn to the box that holds the trophy.

Today after the meeting, I quickly snapped a few pictures of the box. I tried a little bit to remove the teapot, but I couldn't see a proper way of doing it, so I stopped before breaking something. While writing this, I got to think of that I think the correct way is to lift out the upper part (the teapot itself), and then remove the base.
I tried to pull a bit at the middle shelf surrounding the teapot.

Technically the trophy isn't part of the ship, but this is my blog, so I decide that it is OK anyway.
According to a link I found, the Trophy was established in 1964

You will be able to find some pictures of the teapot itself in the first link, but here are a couple of other pictures of some details of the box.

I can't see how the box itself is constructed, I mean if it is with secondary wood and veneered shell -or solid wood with blind dovetails. But the overall size of the box is something like 16" x 16" and 8" deep and inside it is lined with some dark blue velvet.
Neither of the screws are clocked which I find a bit strange, after all I am certain that the box was made by someone professional.
The original silver plate on the right hand door has nice engravings, whereas the new silver plate inside the lid has got some not so nice machine type engravings. This is to be expected,as engraving is not something that any goldsmith can do anymore as far as I have understood.
The bracket holding the top of the teapot in place is clearly made with a Forstner bit. I think that is the one detail that look the most out of place to me. Using a Forstner bit is OK to remove the material, but it wouldn't have taken much to take a spade bit of a similar size and ground it to a round shape. Then carefully rounded the bottom of the hole.

Now all this may sound as I am ungrateful for the Trophy which is not the case. Instead I would say that I find it intriguing that after having built stuff myself - I am able to see that not everything that was made 50-60 years ago was better than what could be built today.
Maybe the cabinetmaker tasked with the job had to work on a tight budget because the teapot itself had cost more than anticipated, so a bit had to be saved on the box. Or maybe it was someone who had never heard of clocking screws? We will probably never know.

Silver plate on top of the box.

The closed box.

Hinge stay, new silver plate visible inside the lid.

Description of the inspiration for the trophy. 

Teapot lid holding bracket closed.

Let's just use a Forstner drill, no one will ever notice..

Statsraad Lehmkuhl details 2, braces blocks

This is one of the details that somehow looks incredibly attractive in my eyes.
We have four of those "stations" on the ship. Each consists of 3 blocks of varying sizes, all mounted pivot-able on a common axle.

Each block is for a brace. A brace out here is a line/rope that will pull a yard and thereby altering the angle of a sail in relation to the ships hull. That way you can adjust the sails to perform if you alter the course.

These particular braces blocks are located on the port side on the main deck, and are connected to the three lower sails on the fore mast.

The lower sail is named the "Fore sail", and its brace is "fore brace".
The sail just above is the "Fore lower topsail", and its brace is " fore lower topsail brace"
The third sail from the deck is the "Fore upper topsail", and its brace is "fore upper topsail brace" (what a surprise!)

The block for the fore sail brace is the biggest one, it measures 12" in height, 15.5" in length and it is 4.75" thick.
All three blocks are made out of mahogany.

Port fwd braces blocks station.

After sunset 

The author of this blog 

(we had a pirate cruise for kids today)

Statsraad Lehmkuhl details 1, mast centering blocks

As you might have seen from Don Williams' blog post where he visited the ship, there are an incredible amount of details on this ship.
I will try to see if I can make it a habit to blog about one detail of the ship on a regular basis.

Those details are not necessarily the most important ones in respect of keeping the ship afloat, but they are details that have intrigued and impressed me.

All our masts are the original ones from 1914, they are made out of steel plates that have been rolled to shape and then riveted together, They taper all along the length, and I am still horrified thinking of that in order for those mast to be riveted, it means that someone had to hold a bucking iron on the inside of the mast. Clearly those were the days prior to any interference from occupational hazard inspectors!
Using ear protection was not custom at that time, so I am afraid that the building of this ship and others have caused deafness to a lot of ship yard workers who had to endure the noise from riveting and other operations.

The main mast (the middle one) goes through 3 decks. The main deck, the tween deck and the provisions deck before it is finally seated in the ballast deck.

The mast can be dismounted from the ship, and we do this occasionally for inspection purposes.  I haven't participated in this yet, but I hope that I will be on board next time we have to do it.

Where the mast passes through a deck, it does so in an opening that is a bit larger than the mast, something like 6" larger in diameter.
Today's detail are the small blocks of wood that are later on pressed down to fill out that void, and thereby centering the mast in the hole. The blocks are made out of oak and fits neatly around the mast. The uppermost blocks (where the mast passes through the main deck) are covered with sailcloth/canvas that is painted to make the penetration watertight.

The bottom of the main mast of Statsraad Lehmkuhl

Seated firmly in the ballast deck.

Mast centering blocks seen from below (penetrating the provision deck)

The same blocks seen from above (penetrating the provision deck)

Mast and centering blocks and the provision deck.

The blocks in the tween deck penetration seen from below. 

The covered blocks on the main deck (it is raining)

Notice the figure sewn canvas covering.

A fid for a friend

I am back on the ship, and this time our sailing schedule is to do evening cruises in and out of Bergen, so I have the rare pleasure of a functioning Internet connection that comes with being alongside in our home port.

Some might think that evening cruises are a bit dull, but just like all woodworking can't be ebony inlay, once in a while you need to build the casework that will house the inlay.

These cruises with paying guests are part of our bread and butter, and in addition to providing the ship's foundation with some needed cash to run the ship and keep her well maintained, these cruises actually give the residents of Bergen a sense of ownership of the Statsraad Lehmkuhl.
So it is part of our strategy to be active visible and accessible in our home port for two months of the summer every year. That way people feel proud of the ship and recognizes it and feels that it is "their ship."

The incredible support that we have from the local community can not be overestimated, so it is only fair that we do our part in giving back to the community by doing these small evening cruises.
And just like in woodwork, it is difficult to say that one operation is more important than the other.

Since there are comparatively few tall ships on a world wide basis, often young people who wants to work in this field have a difficult time finding a ship to do it on, we usually have 6-8 volunteers sailing with us, who have completed their basic training on a training ship.
One of these volunteers told me last time I was on board that his birthday was tomorrow, (we discussed it because it was close to the date where I was signing on again).
Now these volunteers get room and board and that is it, but they do an incredible job on board, so I thought that I would make him a small birthday gift.

So a week ago I took the time to head into the shop and I turned a fid for him. It is made out of some dark exotic wood that I once purchased, and I think it might be mahogany, though I am not sure.
Turning a fid was pretty straight forward, and in the end I tried to polish it with some Carnauba wax. I have never tried this before and I was so impressed with the look of the surface that I ended up making yet another fid for him. This time a bit smaller.
He doesn't read this blog, so it will be safe for me to post a picture of the large fid here. I forgot to take pictures of the smaller one.

The large fid has a length of almost 12", and the thickness at the fat end is something like 1.5"
I can't remember the size of the smaller one, and it is already gift wrapped.

Protect the whales

Before leaving to sea last time, I cast two more drafting whales, so I had a full dozen. Once I had done that I painted all of them. First a coat of primer and then followed up by a classic tractor colour: Massey Ferguson light grey.
That made the whales look nice and grey, but I was aiming higher!
I found a bit of white and painted eyes on all of them, and finally a little black made the pupils. I made a couple of whales that were "concentrating" on the task, and I also made a couple of whales who were rolling their eyes.

Since I wasn't going to use the drafting whales a lot, (and because I like making boxes), I decided on making a dedicated storage box so the whales could be protected between the jobs.

I dovetailed a little chest, and glued in a couple of strips to hold up the bottom.
The bottom was fitted with pie shaped compartments, to keep the whales apart to protect them from rubbing against each other.
A loose upper part was made the same way, but not glued in, now the chest could hold all 12 drafting whales.

A set of handles were mortised into the ends of the chest.

I also found a piece of larch wide enough to form the lid, but that was as far as I got that time, so I still need to make a lid and mount it.
Originally my plan was to paint the chest in some sort of marine inspired theme, but so far I would be happy if I just got the project completed.

There are as usual a lot of different projects requiring my attention, and this box is not very high up on the list. Instead stuff like getting the old Volvo Valp through MOT and installing tiles on the roof of the barn near the summer house are top priority. In addition to this there are a couple of confirmations (one of them is Asgers), and two limousine "jobs" with the Volvo Valp for my nephew and for Laura's prom dance.
But at least the whales are all done now :-)

Drafting whales in action.

This little fellow just about had enough.

Holding a batten in place  

Drafting whale storage box.

Casting a set of drafting whales

I have earlier expressed my interest in building a boat on this blog, and I have slowly gathered information from books, blogs, etc. on the process of doing so.
I even purchased a set of drawings for a small lapstrake tender (the "irreducible" by Weston Farmer) and believe it or not - I milled some larch for the project a couple of years ago, so it would be ready whenever I was.

Before building a boat, you are supposed to loft the plans, which is a fancy expression for enlarging the drawings to full size on e.g. a piece of paper.
Boat drawings come with something called a "table of offsets". These represent positions in a coordinate system, and then once all are plotted you connect those dots and that should give the finished plans of the boat.
There is a small but important thing to notice about this dot connecting business though. The lines are not straight lines. So you need a flexible batten to help you draw that curve. Furthermore, the curve is not the same all along its length, so you will need something to hold the batten in place at various points while you adjust it, and then finally you can draw the line.
Those things are known as drafting whales. (drafting ducks, lofting ducks or lofting whales are other names for them).

For a couple of years I have regularly fantasized about casting a set of those. But I wasn't sure how to make a mold that would give a really nice result without trying to learn sand casting, and I didn't want to spend an enormous time on achieving anew skill for this.
A thing that kept holding me back was that I had the idea that those whales had to look really nice. In a way this suddenly became vital for the positive outcome of the planned boat building adventure.

I mean how could I ever present a boat that I had built unless the drafting whales used were perfect? Probably the majority of people who would ever see the boat would immediately demand to see the drafting whales I had used for lofting the plans!
It wouldn't matter if the boat was pretty and tight etc. because clearly those whales were the most important part of it all. Actually the reason why people build boats was probably so they could use their drafting whales.

Finally this time while at home I managed to get a grip on reality, and consider that maybe people wouldn't care if I had used a heavy stone, an old flywheel, a lead ingot or a horse shoe instead of a perfect whale when I laid out the lines. So maybe it would be OK to cast some even if they ended up less than perfect.
It was a daunting thought!

So somehow at a quarter past nine in the evening, I headed into the shop determined to try to make a wooden mold.

A piece of larch was split in the middle on the table saw,  and I quickly sketched the profile of a fat little whale on one side of it. On the adjacent side I sketched the outline as seen from below.
That didn't take long.

Finding a sharp gouge and removing some material was also very fast. In very little time, I suddenly had half a mold.
I held the two sides of the mold together, and traced the whale profile from the first mold to the second piece of wood.
Removing the wood was just as quick, and in just a bit more than an hour I ended up with a decent mold. I couldn't believe that it had taken me several years to gather the courage to do it.

The next day I melted some lead from old tire weights and some sheet lead that I had lying around.
A 3" nail was bent and inserted in the mold. The two parts were clamped together in the vise, and I poured the lead in.

The first whale casting caused a bit of bubbles, because of all the gas that would escape from the charring of the sides of the mold.
The next casting was perfect until I opened the mold too soon.. It broke in two.

After getting an idea of the solidifying time, I ended up making 10 whales. In the end the mold became more and more charred, so the whales started getting a larger and larger back fin.
But it will be no problem to remove this with an ordinary knife.
I plan on painting the whales after removing the surplus lead from them. But that will happen at some point while I am at home.

First half of the mold.

Mold clamped in the vise.

Filled with molted lead (now solidified)

The first whale is the one with a bit of color.

Notice how the back fin gets bigger.

Mini Max hydroplane 2, completing the boat.

After assembling the hull, I had to work with epoxy and fiber glass for the first time in my life in connection with wood.
Technically I got to think of that I have used some before back when I was an apprentice on a reefer ship. It was used to make a temporary repair of a leaking pipe.

First I rounded the edge a bit, and then mixed the epoxy, applied some and put on the glass fiber. It looked really fine for half a minute or so, then the glass fiber mat started to creep up and loosen from the rounded corner.
I added more epoxy and brushed it down again, but to no success.
After a while I concluded that I should have rounded the corner a lot more. So I stopped for the day.
The next day after the epoxy had hardened, I used one of my large rasps (a farriers rasp/file) and made a much larger rounding on all the corners of the hull. I ended up making a rounding with a radius of approximately 3/8". For information, I am using a slow setting epoxy to give me a bit more working time when applying the stuff.

This time the fiber glass stayed in place and it looked good.

After another day, the epoxy had hardened, and I sanded the edges of the mats and also sanded the surface of the hull.

Asger and I helped each other priming the boat. The primer dried quickly, and the next step was to paint the bottom.
We used a real marine primer, but for the top coat I opted for the classic boat color: New Holland agricultural machinery rim white. Conveniently available at our local tractor dealer just up the road.

When the bottom had dried some, we helped each other flipping the boat around, and I painted the top with the white paint. I painted inside the cockpit, and the corners of the hull plus the center stripe.
More waiting time, (I am not that patient when it comes to painting). And it was time to apply the green color.
The first boat was going to be Gustav's boat, and since he had gone to Mette's uncles place to help in the harvest, I had decided the paint scheme. The green was again an agricultural paint (Krone hay and forage equipment) because that is also a product they carry at the local tractor dealer.

Suddenly the boat was completed, and more so, it looked just as I had imagined.

Part of the reason it was to become Gustav's boat was because he had once been given a small 4 hp outboard motor from his uncle, so we had made the motor mounting board a bit longer than described in the plans - to accommodate the long leg of that motor.
Asger also thought that it was a smart move to get the second boat, because that would hopefully mean that all the messing up had been sorted out on the first of the series.

Late that evening, we tested if the paint had dried, - and it had.
It was completely calm without a wind, so Asger and I immediately decided to take the boat for a test.
He found a wet suit, and I mounted the handles at the transom and on the fwd part of the hull, to facilitate moving the boat.

After a slow initial run, I discovered that the throttle could be pressed further to the side, and suddenly the boat was planing, just as it was supposed to do.

All in all a very successful project.
Now we are on the look out for a reasonably priced outboard with 10-15 hp. But given the much nicer weather than normal, all outboard engines have risen considerably in price. But maybe we will get lucky during the winter time.

Ready for the first test of the boat (motor not yet mounted)

Asger mounting the upper part of the hull.

Farriers rasp for rounding corners prior to epoxy and fiber glass.

My younger brother Jens visiting from Japan (being put to work)

Sanding and dusting off at the same time.

Asger priming, cousin Kai and Jens admiring the work.

Boat primed.

Ready to fly.

60'ies inspired paint scheme.

Mini Max Hydroplane 1, assembling the hull.

When I got home I was determined to start building a couple of Mini Max's
I never expected the biggest obstacle to be that the lumberyard had run out of 1/4" plywood. Somehow it took them 3 days to get hold of something so I could carry on with the build.

I also had to call the company where I had ordered some epoxy and glass fiber cloth, because that package hadn't shown up either. And I ordered that a week prior to going home.
I got a less than enthusiastic person on the phone, and as soon as I had explained my reason for contacting them he replied: Oh yes, I know about that package, we have thought about contacting you for some time, because the one item you ordered is out of stock (3" wide fiberglass tape). I had to struggle to stay diplomatic, but we ended up finding a solution to some wider tape and some large square mats instead.
But why for Heavens sake does it have to be that hard to get a little bit of service . I mean they could have mailed me as soon as they got my order explaining that despite the web shop showing the item it was out of stock and they could suggest this or than instead.

A bit of searching in the piles of lumber at home brought forth enough 8" wide larch to build two boats with, and also some narrower stock that I used to make some strips as the plans called for.

Both the boys were really exited about the build and they were able to participate a lot due to a low weight of the individual pieces, and the ease of construction.

The first boat I tried to make exactly according to the plans. But after a little time it became apparent that the plans are not 100% correct.
The two stringers for instance that will form the sides of the cockpit were too tall, but none of this was a real deal breaker. It was more an eye opener to me, that I couldn't make x number of pieces and then assemble it like it was a jigsaw puzzle.


The most difficult thing about the build was indeed the closing of the slit on the lower part of the hull.
I had seen and read various fine solutions on how to overcome this task - so off course I had to invent my own way of doing it. Please see the final pictures for a short guide on how I did it.

I clamped a batten on each underside of the slit, using two clamps for each batten.
With the battens securely in place, I used a clamp on the battens to squeeze the two sides together. It worked just as I had imagined.
The hardest thing is to make sure that the battens don't shift while squeezing them together. This is why each of them has to be secured with two clamps, and off course a piece of wood on the top side to protect the plywood from being marred by a heavy pressure from a clamp.

I made sure to place them a little distance from the slit, so that once it had closed up, I could put screws into the "fore strut".

Asger showing the boat with the top temporarily in place.

Gustav sawing out a paddle, Thomas (friend) watching.

Asger mounting the transom.

Planing a bit of the fore cross piece.

Asger stepping off distances with a divider.

1) Clamp on the fore cross piece

2) Clamp on a batten on each side of the slit (underside)

3) Each batten is held in place by two clamps.

4) Force the battens together using a clamp.

Mini Max hydroplane

Update on the virus warning in the comments:

I just received a mail from the administrator of the Muskoka seaflea page, and they were attacked heavily about a week ago. They have had it all cleared, so it should be safe now. 

Apparently a warning can "hang" in the system until you update your browser?

Quote: "some times the cache on a visitor's browser will hang onto the "warning" until their browsing cache is refreshed"

Thanks to a much better than normal summer (hottest in Denmark in 150 years or so), There might be a real chance of some time spent at the beach.

Gustav has long complained that we haven't got a boat. When I tried to tell him that we could probably get a rowing boat or a small sailing dingy, he looked at me the way only a frustrated teenager can do. The look that clearly tells you that in his opinion you must be living in the 20th century (which happens to be correct for my part)

Sitting out here without a definite woodworking project going on, I started surfing the web for some inspiration. I have always admired those small hydroplanes from the 60'ies. Those on the cover of Popular Mechanics etc. Nice looking cover articles from a time when the western world was pastel coloured - and smoking and drinking was recommended by your local doctor as a perfectly legal way to wind down after a long day at work.

There are a couple of places that has those old designs available as free pdf files for downloading.
I ended up at a place called Muskoka seaflea, they had just the right plan for me.

The incredible Mini Max Hydroplane.

It is made out of two sheets of 1/4" plywood, a bit of regular wood, a little bit of epoxy to seal the edges and that is about it. According to the article, you can build it in two days, or one day if you have some woodworking experience.

Back in the days this little boat could apparently be built for 20$. That figure doesn't quite get you there today, but I have made a loose budget, and I think that I can probably build it for something like 200$. The most expensive stuff being the epoxy and the paint.

We have an old 4 hp outboard engine, and that will have to make do for a start. If it is a success, I might have to look into finding a more powerful motor later on.

I have spent a bit of time figuring out the radius of the curves shown on page 2 of the instructions.
Those old plans can seem a bit vague compared to what is available nowadays, but since they are free you can't really complain. And if it was possible to build one 50 years ago based on those plans - I can't see why we can't do it today.

According to my calculations, the radius of the "fore center strut" is 85.4"
The lower radius of the "fore cross piece" is 86.2"
The upper radius of the "fore cross piece" is 102.1"
We'll have to see if I am correct once I start building the boat.

The plan is off course to get the boys involved. The individual pieces are not very heavy, and today with the possibility of using screws instead of nails, the buys can really play their part.
If all goes as planned, I will be back home Tuesday night, so Wednesday would be a logical starting point with a trip to the lumberyard for some plywood and possibly some screws.

In the free world, it is probably legitimate to let your children play in a speed boat. But guess which country that has regulations for that as well..
But being the less than enthusiastic citizen that I am, I looked at the official page from Søfartsstyrelsen (the Danish equivalent of US Coast Guard) to see if the rules were possible to work around.
The rules state that you have to be 16 and have a speed boat licence if the power of the boat is more than "the square of the length +3".
If the boat is of a planing type and it is shorter than 4 m (~13'), you need to be 16 and have a licence if the engine has more than 19 hp.

So by making a really short hydroplane I elegantly manage to circumvent the regulations, and can let my kids use the boat to their hearts desire. As long as I stay below 19 hp. But given that the design suggests a maximum of 15 hp that shouldn't be a problem.

Has anyone thought about building a boat, or perhaps done it?

Like the title says, Have you ever considered building a boat, or perhaps even done so?

I have often thought about making a small rowing boat. Maybe like a dinghy that used to be hung at the rear of a larger vessel in the davits. Nothing large, actually an 8 or 10 feet boat is kind of what I had in mind.

I don't like sailing much though (I get enough sailing from my work), but building a boat has always had a strange attraction. I like the looks of traditional small boats, and I think that it will be a challenge to build one. The problem would be what I should do with it once I eventually finished it?

If I start a project like that, it deserves to get full attention, so I couldn't just rush it to end up with a boat shaped object.
Off course there are the usual obstacles like other projects that would be fun to make, some horses and a dog that needs to be tended to etc.
But that shouldn't stop anyone from dreaming about future projects.

The "dream boat" will be made out of larch on an oak frame.
Probably planked, but I have also been tempted at times to dream about making one with a smooth outside, all the boards are pressed together edge to edge, and tarred fibres are pressed in between.
In Danish this building method is called "kravel" I don't know the English term for that.