Spyder micromultihull is born



• In 1986, a pair of similar catamarans were built at Chalmers University by two engineering students with previous experience in building boats, they also had the support of a committed and knowledgeable lecturer at the university. The boat building is described on Martin's website, which has a lot of other technical information about constructions.
• Martin continued to develop his catamaran while the other (Juguete II) "stood still" and ended up in Vänern at the turn of the century. I was delighted to take it over in 2008 and quickly realized that it needed care and improvement.
  Scarlattikvarten is created

• Renovations and improvements

  Minor repairs would have been enough, but since I was a boat builder (both wood and plastic) I invested in major renovations that spanned a long time.
  The first thing that was done was to replace some parts at the cockpits. Plywood parts like deck, bench seats and bulkheads were renewed. All grommets was removed and deck sanded clean.
  Other improvements were also made to beam mounts, cockpit protection, etc. All of this received new layers of 160 g twill/epoxy and all penetrations were reassembled with special sealing. The deck was painted with a special version of polyurethane including non-slip powder. New trampoline nets and attachment methods for these were installed. The trailer was improved and received support legs at the front.In order to be able to more easily bring the hull together over the mast beam, stainless steel carriages and bottom supports were manufactured.
• The next major renovation concerned the outside of the hull, where everything was sanded down and covered with new layers of glass/epoxy. Below the waterline, the bottom and stems were reinforced with 400g biax and additional layers around the daggerboard openings were added. The entire hull planking was then covered with 320g Biax/epoxy.
  In order to be able to more easily bring the hull together over the mast beam, stainless steel carriages and bottom supports were manufactured.
• The lower part of the stern and the rudder mounts were changed to avoid some bolt mounts and to be able to grip the stern. The bottom below the waterline was painted with primer epoxy, varnished surfaces with polyurethane and the deck was repainted. A few years later I changed the stern and rudder details again. This time, handles were constructed to be able to get up/down in the sea and that the lower part became an extension of the stern of the hull.
  In order to do mounting of the hull alone etc, I created several aids, i.a. the two stainless carriages that made it easy to move a hull sideways. The Trailer has been improved several times to easily handle the hulls in a safe manner. The trailer now has new tires as well as the carts that the hulls are in.

• A major change was that I built deck plates. They were made from Divinycell H60 with strength calculations from DIAB.
  Edges of the slabs received 4 layers of 600g UD strips, laid one edge at a time with form boards clamped around the divinycell slab. All penetrations consist of fiberglass pipes. The surfaces were first covered with 450g bidiagonal and then with 440g unidirectional fiberglass. Underneath, beams and attachments were made for a new engine nacelle. The nacelle was made of thin Bonucell with 320g biax glass. Mixing paint and building a nacelle
  The underside of deck tiles is painted with primer epoxy only to be able to laminate easily when needed. The upper side is primed with colored epoxy then covered with polyurethane varnish in different colors (dry pigment) and with halanix powder in the last layers. Lamination of new deck
• I discovered a strange damage after a heavy rain. The hulls where ashore with the bow downwards so that water could not run out aft. Water pressure pushed H2O through some micro holes. A similar damage happened a long time ago in the same place (which was fixed) and now I understand how water could get where it shouldn't be. Normally all water drains out of cockpits and "anchor boxes", no damage has occurred in all these years. It affected the bonding between hull planking and lamination on some parts. Externally the hulls were already fully protected.
  Because of this I did an extensive renovation of all the interior surfaces in the cockpits and also in the front cargo spaces. Laminate was removed on the cockpit wall and also on a larger surface outside. These surfaces received new laminates and several others were reinforced. The wooden planking was completely undamaged, but I'd rather do more than minimize repairs

• Tunnel tent

  Many larger works have been done inside a special tent with a tarpaulin that lets in light. It was created to fit the Juguete with all its accessories up on the trailer. If a future new owner of the catamaran would need such a tent, I can imagine a low price.

• Finito once again

  The last thing I did after the boat was taken up in 2023 is to look over some painted surfaces, penetrations and to sand down all the bottom paint. I had tried a type that unfortunately did not work well in our waters.

Questions via mail Hans Nilsson