Few plans are out there allowing us to have a jump start on a scratch build. I came across Lonewolf (Shockerman) 8 years ago and he generously gave me his plans. I have built half a dozen different permutations of these plans and have recently scaled them to 34" and tweaked the tunnel height/width, tunnel attack, downward force from deck and angled out the sides somewhat aggressively.
I have watched my slomo vids and seen that many cat rolls are initiated with a forward pitch and slight roll - then the water slips up over the deck and initiates the death grip. SO, I thought a slightly outward slant (not unlike a mono bow) would add lift in such a pitch/roll event and so far in the 24" and 12" it has worked great. For the 34" hull, I decreased the angle so as to not add lift to the bow, which if racing near 60, this could increase blow over potential.
This set of plans is pretty simple and requires a good bit of patience; trial and error fitting and some design-as-you-build technique.
Before I started adding CF rod, plate and cloth, it was pretty economical... but now its strong. I have not gotten these plans laser cut, rather I plot them, cut around the parts and paper glue them to the balsa. I use a combination of utility knife and straight edge and bandsaw.
supplies:
3/32" balsa sheets (6" wide by 36" long)
1/32" ply sheets (same dimensions)
1/4" square stock (bass)
3/4" 45 triangle balsa stock 2x36"
1" and 3/4" trailing edge balsa stock 2 each x 36"
5/8" leading edge for wing (front of the tunnel)
CF rod, 1x3mm by 36; Cf plate (1mm) and CF cloth
CA and kicker
West Systems epoxy (I used 205 hardener)
US composites 2 part expanding foam (2lb/cubic ft)
industrial rubber cement (for adding the ply skin to the balsa sheets)
Sandpaper, block
building board 7.5" wide, 2" deep and 36" long wrapped in wax paper
I will be less verbose in the posts but will answer any questions that may arise.
pic 1: dog with a boat for scale. the frame goes together pretty quickly and I recommend using a building board wrapped in wax paper. The flatness is crucial and the closer to the exact tunnel width the better. I forgot the wax paper and thus in pics 3-5 you see I used some CF strands to beef up the corner. then I covered my booboo on the tunnel side with 45 angle balsa. I got the idea from my M1 Super Cat hull.
Pic 5 shows my motor mount CF plate - this will be designed for either twin or single. In fact, I'll be putting in the tubes and motor mounts for twins just in case I want to see how fast I can get her going.
Bookmarks