The resin is working really well

Researching which resin to use in the beam build led to lots of choices, a big range in pricing, and many opinions. At about 10 gallons in, and 3 of the beam-cores out of the mold, I’m really happy with the DR-5 “toughened” epoxy (and the corresponding EH-102) from Applied Poleramic in Benicia, Ca. Of course it’s a big benefit they’re within an hour’s drive from the shop, but more convincing was the fact they are ‘Farrier friendly’ and reportedly supplied the epoxy for a bunch of the F25 Carbons built in Colorado. They were very helpful over the phone as we talked about options, and I feel I’m using very high quality material at a very reasonable price (well under any West System prices I could find). The ratio is 4:1, which also helps keep the cost down (less hardener needed than some other systems).

The resin and hardener mix easily and are giving a nice long (about an hour) pot-life which is great for the long, repetitive laminations on these early stages of the beams. It takes the fillers well, too, so the putty-making has been straightforward.  Made a second visit to them in February, buying 3 – five gallon buckets this time. While it would be more economical to buy a big barrel, the convenience and ‘progress payments’ of the five gallon size seems right for this. I’m guessing it will be 20-25 gallons total to build the four beams.

For the first beam, I dispensed using the plastic ‘ketsup plungers’ straight from the big bucket. That was a huge drag, as it was difficult to heat the five gallon bucket enough to get a decent flow, plus it being critical to count every stroke. Finally got smart, stopped building for a day, and got the old StickyStuff dispenser pumps going again (they had seized up with encrusted hardener). Messy, tiresome job, but wow, these guys are the new heroes of the workshop!

They look a little funky, but the tank-internals are now clean and the dispensing tubes have been replaced. The unit on the left is a 4:1 mix system, and the right is a 2:1. Now we can make as little as an ounce of mixed epoxy, or very quickly do big pints in quick succession as needed for hand-layup.  Had to call these guys with a question the other day, and they were great.

Aft starboard beam-core came out of the mold the other day, and tonight the first lamination of the 4th beam got underway. Hopefully by next week you’ll see a photo of all four beams lined up on the table starting to get the complex inner web systems underway!

Starting the Aft beams

The forward port beam popped out of the mold much easier. It’s in the front of the photo, getting it’s core-outer wrap layer. On the first beam I wrapped the tape transversely, but it was difficult to get a perfectly flat lie on all surfaces. So we’re trying the second one down the length of the beam instead. The tape is DBM1708 45/45 angles, so I don’t think the orientation matters for strength. Running crosswise on the first one left lots of ridges to sand down.

Now it’s on to the aft beams. Same mold frame, but these two will be a few inches shorter. See the endplate moved inboard a bit at the bottom of the photo. Tomorrow this one gets its bulkheads installed.

Forward Starboard beam is underway

005’s plans were delivered from Farrier Marine 16 years ago; she’s got 3 nice hulls sitting next to each other, but not connected. 2012 is finally the time for the beams!  Spent New Year’s Day building the form out of 3/4″ particle board. In the interest of saving the lower back, we’ve lifted the whole works up about a foot on four heavy blocks – that’s been great so far during lamination.

“Forward Starboard” gets started. Grey foam is 5lb/cubic ft density, yellow is the no-compress 12lb. Diagonal brace tangs will be cut in to floor of beam in yellow section. Beam bolts go thru solid resin seen on the end-plate.

Core layers of DBM1708 tape laminated.

Each lamination step on the beams seems to take about an hour, so weekend days get second (and third) concurrent projects. Starting on the main hatch cover here. Secured the foam to the original hull cutout to get the right arched shaped.

Backing plate inside the instrument pod. planning on tacktick wireless, but Dad thinks I should install a wiring channel just in case. Not a bad idea.


ForwardStarboard released from the mold after bulkheads were installed. Didn’t use enough non-stick tape inside the mold; two spots of resin from seams got the particle board, causing a dumb half hour of careful prying and banging to get the release. All minor dings repaired. Yellow foam horizontal line is the zone for backing plate inside, to handle the trampoline lashing eyes.