Bionic Broomstick
There was some stuff about this particular craft toward the end of the Nomad thread plus a couple of other mentions. Appropriate since the Bionic Broomstick is a trial horse for a couple of concepts central to developing Nomad which is where my heart lies.
BB was originally conceived as just a down dirty and cheap way to test out some ideas on rigs and rudders. But it has taken on a life of its own even though it’s not something I’d use regularly, suffering greatly in comparison to a solo canoe in a number of important particulars,
Unfortunately work is going to be sidelined for a couple of months while I recover from shoulder surgery but before that happens I pulled the pieces out from under the house and took a few pictures to cogitate on while recovering. The assembled pieces weigh in at 80# even, still lacking sail and a few odd bits, am pretty happy with the weight except for the main hull at close to 55# will be a little challenging to load on car top. Assembly is pretty quick and easy, center of gravity falls just about under the heel of the mast and is pretty easy to pick up and scrunch around,
There will be two different rigs to trial out, a cambered panel bidirectional junk based on past work and a cambered panel jib based on Chris L’s Snelsons Canoe work. I’d hate to give up on the cambered junk after having spent so much time on the thing but if the cambered jib works out it is a winner hands down. I really look forward to finding out, it’s just going to take a little time.
Skip
Well, that’s the first bass boat I’ve ever seen that doesn’t have 200 hp hanging off the transom. 😉
Damn, shoulder injuries seem to be all the rage here on the forum - best wishes for a speedy recovery. I’m really interested in all the experiments planned for the Broomstick - these are things we’ve all mused about for many years, its about time they are tried out.
WOW! Looking good, Skip.
Tetrahedrific! Can’t wait to see more.
best,
chris
Hi Skip!!
How is your beam attached to your main hull and to the ama? It seems to me that you could end up on both ends with very high loads, not so much in torsion (your ama is so short that whatever the main hull pitch angle, the ama will follow), but in “bending”. I guess your ama is your leeboard, right? In that case, lateral load applied at the bottom of the ama (with a substantial lever arm, since it is fairly deep and the hydrodynamic forces will be quite lower than the beam attachment) will try to “rip off” the ama from the beam, which is attached to it on a very small length, due to the narrowness of the ama.
Wha d’ya tink?
On the other hand, I most likely over engineered mine, by adding “triangulation” sticks, from fairly low on the leeside of the ama, to the beams, about 18” more inwards than the top of the ama…
I am looking forward to some sailing videos…
Cheers,
Laurent
PS; after extensive rebuilt (daggerboards trunks, beams ends to fit in main hull sockets), in not so good repair conditions (a gazebo tent in equatorial rain does not cut it to make epoxy resin repairs…), I am almost ready to go sailing again!!! When I say “almost ready to go sailing again”, my wife laughs…. I wonder why…
Hi Skip!!
How is your beam attached to your main hull and to the ama? It seems to me that you could end up on both ends with very high loads, not so much in torsion (your ama is so short that whatever the main hull pitch angle, the ama will follow), but in “bending”. I guess your ama is your leeboard, right? In that case, lateral load applied at the bottom of the ama (with a substantial lever arm, since it is fairly deep and the hydrodynamic forces will be quite lower than the beam attachment) will try to “rip off” the ama from the beam, which is attached to it on a very small length, due to the narrowness of the ama.
There is a molded socket that fits over each end of the beam and is epoxied and glassed to hull and float respectfully, will post a close up later. The sockets are about 12” long and held together via the diagonal lines from hull ends to beam/float connection. Predecessor ACDC relied on fairly flimsy pvc struts and stayed together.
I am looking forward to some sailing videos..
.
No more than I am to providing them 😉
PS; after extensive rebuilt (daggerboards trunks, beams ends to fit in main hull sockets), in not so good repair conditions (a gazebo tent in equatorial rain does not cut it to make epoxy resin repairs…), I am almost ready to go sailing again!!! When I say “almost ready to go sailing again”, my wife laughs…. I wonder why…
I’d ask Susie but would have a hard time helping her up off the floor with just one working arm 😉
cheers,
Skip
Good to see BB developing, lots of interesting design ideas here. It all looks well thought out. The overall simplicity of the configuration obviously appeals to me, you initial designs where the inspiration for my minimal proa. I like your rudders, does the bow rudder lock or are linked and counter rotating? They look well engineered for good hydrodynamics. With the black ‘camouflage’ vaka (looks like you have a similar plan for the ama) BB will create quite an illusion on the water. I will be interested to see how the ama works out, very unusual but the concept sounds logical.
We should start a new forum for proa nuts with shoulder injuries, it is a real downer particularly in the hight of the season. Sounds like you plan to cognitate proas while you recover, never wasted time, I look forward to a flurry of posts with more great innovation.
Anyway good luck with the shoulder, hope it goes well and BB is afloat soon
Tink
wait…I thought this WAS the forum for proa nuts with shoulder injuries.
feel better soon…
Hi Tink,
Hope your shoulder is well mended, wouldn’t do to have both of us out at same time 😉
The rudders aren’t linked, just steered with a push pull stick, the forward one clips into a bracket on the seat edge to fix in place. May play with turning a degree or two to see what happens, but that’s way down the list.
Rudders themselves will retract and extend on a continuous line that runs along the top of the push/pull sticks. Adjusting the depth of forward rudder is possible but I’m biased towards having the thing full up, we’ll see.
Attached is a picture of the beam sockets I promised Laurent.
Cheers,
Skip
Hi Tink,
Hope your shoulder is well mended, wouldn’t do to have both of us out at same time 😉
fixed good enough to sail on Saturday but just back from the consultant and he is not happy with the movement, may require an operation, not happy with that. Off for more physio in an hour
The rudders aren’t linked, just steered with a push pull stick, the forward one clips into a bracket on the seat edge to fix in place. May play with turning a degree or two to see what happens, but that’s way down the list.
Rudders themselves will retract and extend on a continuous line that runs along the top of the push/pull sticks. Adjusting the depth of forward rudder is possible but I’m biased towards having the thing full up, we’ll see.
Cheers,
Skip
Sounds well sorted, boy have you got me thinking. Your setup is ideal for the counter rotating rudder which worked on TP02. If I hack a 8’-10’ off each end of TP03 and fit removable counter rotating rudders I solve my storage issues.
Picture of TP02 with his counter rotating rudders, ignore the possible next step bit
Tink
Finally getting close!
Got all the done bits out together and no great surprises in assembly. Time and approaching rain shut things down a little earlier than I wanted, but was nice to see it all together.
Really happy with the rudders, go up and down easily, stay in place, at least statically, feel good “steering”.
Not that hard for one guy to set things up but there will definitely be a trailer in the mix, hull is just a little too heavy for an old fart like me to car top and there’s just too many pieces. And this is before the wing is done.
Roll up boom works fairly well considering the general roughness of the build, looks like reefing will be a stop and do it rather than furling on the fly but suspect that Nomad will be easier with better build and a little experience. Biggest issue is the clunky two part battens screwed thru the sail, a real sewn sail with batten pockets should be an order of magnitude or two better.
Will still be a while before we hit the water, several little bits to be done yet plus the trailer and wing sail. Also a few weeks from being released by the doctor and more importantly my wife.
Skip
New image format rocks!
That is one cool mock up. I love the sail. The whole thing is tensegritastic.
That is one cool mock up. I love the sail. The whole thing is tensegritastic.
It owes a lot to Snelson’s Canoe
The rudders alone are a breakthrough (if they work). 😉 This is really going to be a very cool proa test bed.
But to hell with the boat, I want to see more of the cool structure with chevron patterned planking and stone masonry columns!
I’m glad the image uploading is working out. I increased the max image upload count from 3 to 6, it seems like the new server can handle it easily.
Looks very cool Skip
Good luck getting the shoulder signed off by the wife. Really looking forward to hearing how this wonderfully thought out boat fairs on the water
Tink
But to hell with the boat, I want to see more of the cool structure with chevron patterned planking and stone masonry columns!
Always try to keep the Editor happy, my first thought was the chevron reference was to thread #150 😉
Image attached of front of the house. Hyperboloid structure of the A/C support an indication of my geometric obsession. Proa content, wind chimes at the stairs made from zero temper alum tubing (my fault, didn’t look that close when ordering) for telescoping beams on P52.
More proa content, was going to finish up tripod, cam and follower bits for BB today but too dang cold outside, picture is where it’s at today.
Skip