Top rear fuselage for Shark 45

I am building a Lew McFarland Shark 45 and I need some help with the rear top of the fuselage. Has anyone built a mold for this part of the ship that I can either buy or use? I'd really like to mold this piece, but creating a male and female mold with both convex and concave curves that tapers with the fuselage is just not within my abilities. I could carve this part but I'd like to build serveral of these planes and molding is the obvious choice for repeatability.

Thanks in advance for any help.
Dave Sabon

Dave,
Molding balsa really does not require such a complicated mold plug and definately not a female (mold that is). If you can carve a block of balsa, you can carve a mold from blue foam even quicker. I've done a whole lot of this in the past 5 years give me a call.

Also, we have 2 very good contests up here in the north coming in August. The "Goyet" and the "Meet & Meat", why don't you grab Mr. Brooks and any other SoCal "fodder for slaughter" and make your way north? The air is cleaner up here.

Phil,
Are you saying I can do concave curves, convex curves and taper wihout a male and female molding buck.

Getting to a contest up your way is tough for me due to the 10 hour plus drive. I can usually take Friday off but both Friday and Monday is tough with my work schedule.

I will call you about this molding project.
Dave Sabon

Hey Dave, it was great to meet you at the Palmer Classic. I too am building the RSM Shark. I must say (with no disrespect to Eric) I was quite disappointed with the kit. My ribs were just blanks, no notches cut for spares or landing gear blocks. The turtle deck cannot be molded, without a male/female mold. It must be shaped from a block and hollowed. I have molded the rear decks and fuselage bottoms on my last three planes with no problems at all. but the compound surfaces with convexed and concaved contours of the Shark will need a more elaborate molding jig. I also feel that if you buy a kit and you are required to mold parts, the blocks to make the mold should be included. Not so with the Shark. Please understand, This is not a post to slam Eric or RSM. Eric is one of greats of our hobby and I always look forward to seeing him at the local meets. I know he is always trying to improve his products and I will be buying RSM goods in the future. Larry, NorCal Circle Jerks

Guys,

Get the original magazine article plans and do it that way. That's how I did mine. The RSM's idea of doing it was just more complicated that I wanted to do! Len Neumann has them, but he is at the Nats right now and can't ship anything out for at least another week.

Jim,
Can you explain how it was originally described in that aritcle? Did Lew carve from blocks?
Dave Sabon

Dave,

There was of course a standard block, but to get the upper potion
a piece of one half inch was shaped and planked on the front with other pieces of 1/2 inch to make the canopy section. Then at the rear the 1/2 was added to with other 1/2 inch sheet to make the rudder outline. the rudder was carved out in the middle and ribs were installed. Then the rudder is sheeted with 1/16 or 1/20th and faired into the 1/2 inch. I think the original also had lightening scallops cut into the 1/2 inch wood behind the canopy area that was sheeted over also. I did my block carving after doing all the laminations. That made for a lot of work but I think it got the rear end of it a tad lighter. Watch out for tail heavyness. It's not a giant concern because the elevator is a higher percentage of the wing area than on other designs of the period. Mine did come out tail heavy according to where the RSM plans show the CG but the plane flies just fine with the controls spaced a little narrower at the handle.

Larry,
I'm really not building the RSM kit. I have plans and a lost foam system for the wing and lots of balsa:)
Dave Sabon