a cool fat tire cub

Ok....so this doesn't have so much to do about the catamaran but Its always nice to think about alternate forms of transportation......The little Hood River airport is home to about 20 piper cubs that are tucked away in the hangars that line the airstrip.. Also, right down the street from the shop, a nice collection of antique aeroplanes and automobiles can be seen at the new Western Aeroplane and Automobile Museum.

http://www.waaamuseum.org/

laying down the glass

So a Saturday and part of a Sunday finds the port side hull clad in nice smooth glass. Again, peel ply tops the epoxy and glass and makes it possible to work the resin out and helps insure a good bond between the foam and the glass. My process goes like this.....smoothe the foam, skim coat with micro/epoxy mix to fill the foam surface. roll on a good wet coat of epoxy, lay down the glass, roll on another good wet coat of resin, top with peel ply and work the layers down with a bondo spreader from stem to stern.

help....

It's nice to have a little help now and then. 44ft. long lengths of 32oz. tiraxial glass is a bit hard to handle so four extra hands makes the job of laminating go much faster.

laminating the exterior, inboard, port side bow

Here's a photo taken while standing one the inner port side hull looking forward. The hull is laying on its side in three cradles. I wanted to glass the hull sections with continuous lengths of glass from stem to stern and you can see the recess strip created with a power planer that allows the triaxial glass seams to overlap flush.

Checking the fit.

another shot looking back into the port side hull. (The outer hull section is on it's side) the inner port side hull section is hanging from the shop rafters in prep for bonding all the seams with a mix of epoxy, aerosil, micro and a little chopped glass fiber.

bonding the port side hull

Fitting the port side hull halves.

starboard hull hanging in the breeze

Here's a picture of the mold being broken down while the hull is suspended from the shop rafters. Notice the stack of mold forms in the lower right hand corner of the photo.

disassembling the mold

Next step........reaching around and unscrewing all the screws that hold all the stringers onto the mold forms.

lift in process

Here's the hull being lifted off the forms. Notice the plastic strips that were placed along the plank seams to keep excess glue from sticking to the stringers.

lifting the starboard side hull

Finally........time to lift the starboard side hull off the mold. I first used an automotive jack and a length of 2x4 placed under the forward bulkhead and lifted the hull about two inches off the mold. This gave me enough room to slip lifting straps under the hull in three places. Using three chain hoists strapped to the rafters, I then lifted the hull about a foot high to provide access to the screws that hold the stringers to the mold forms.

timing the flow...

sometimes it's possible to get an idea of how things are progressing during an infusion by marking saturation lines and timing the progression. Above, you can see the start, 3 min line and the six min line. ....notice the distance betweent the 3 and the 6 is slightly shorter than the start to 3. That's an indication that the resin is slowing down due to its' increasing viscosity.

another little resin infusion clip

pulling resin into a vacuum bag ( resin infusion) is a lot cleaner than wet layup / bagging but it takes a little practice and a bunch of mistakes to learn how best to set up the flow.

It's easy to dive off the deep end into developing technique and experimentation but it's still hard to beat a simple wet layup that's finished off with a bondo spreader and peel ply. ..........knowing when to use the simplest or quickest methods goes a long way towards insuring you keep the project rolling.

infusion clip

resin infusion with a parrot on your shoulder and a video camera in one hand is a bit of a challenge..........

resin infusion

Here you can see the resin being sucked into the bag. infusion requires a good deal of prep work and if you set things up right, it is a very pleasant technique that minimizes potential contact w/ the resin and it can be very neat to watch......it's just a matter of using 3M77 to tack all your dry glass in place, wrap the part w/ peel ply, decide how to pull your resin, build a periferial vacuum manifold, w/ a resin brake then tap the center so that resin can flow outwards.

In this instance, I din't get a full infusion but it's easy to just tap into the bag where it's dry and repeat the process until you get your part.

Parts do come out really nice when things go right......

infusing the starboard side rinterior rails

here's some prep work involved in doing a resin infusion of the interior side rails....these are 10 inch wide webs that have unidirectional glass on the edges that get's bonded into the interior of the hulls. Infusing with system III Silver tip is difficult at best. I find it to be too viscous but if you use plenty of flow media it's possible.

another shot looking forward ....

Preparing the hull sections:


The inner starboard shell is seen here hanging from the rafters of the shop about 10 inches shy of the final resting place. Since I opted to use the foam strips where the bulkheads meet the hulls, I've got a fair amount of scribing, fitting and trimming to do before I invite my friends over for a big cake decorating icing bag, bonding party.........( come to think of it, I need to make sure that I cut the internal access holes in the forward bulkheads so I don't accidentally bond one of my friends into the forward compartments by mistake)



now mixing the epoxy........


bagging the epoxy in preparation of application to the bulkhead edges.....




oops.................

fitting the inner starboard hull section

After a few hours of winching, strapping, grunting, pulling, pushing and pouting......I managed to wrangle the inner starboard side hull section into the general position over the starboard side hull section. From here, I'll spend some time lowering, marking, cutting, lowering check fitting, re-marking, raising, cutting and trial fitting things in preparation of bonding the two hull sections together.

more inspections....

Tang is seen here inspecting the high density foam section of the starboard bow bulkhead. The stem bulkhead is glassed in on the inside and has only been rough cut for now on the outside. From this section forward, will be solid foam shaped and glassed over to form the bow stems.

dragging the inner starboard side hull half

My inner starboard side hull half had to spend a little time in the cold sitting outside by itself along the side of the shop. I glassed it inside and out and decided that the peel ply would prevent any real UV damage. Since it only had to deal with the low winter time sun of the Pacific Northwest, it didn't seem to be any worse for wear.

Todays challenge will to use three chain hoists, straps, levers inclined planes, rollers, ropes, come-alongs, ratchet straps, and mental telekinesis to position this hull section over the outer hull section that is waiting in the mold.

Starboard side bulkheads

Here's Tang walking the plank beside the outer starboard side hull section. I ran this plank along the center line tops of the mold forms to create a convenient walkway.