Of course I have read all the archive threads on this topic and done extenxive search on the internet (http://www.bisect.com and http://www.splitbits.net) http://www.swaylocks.com/cgi-bin/discussion/archive.cgi/read/9519 but nobody seems to have really done it. I want to shape a tilled board myself, I don’t care for patents or anything…I am European and need a board to travel…there aren’t any blanks available but blue/white/purple construktion foam is cheap where I live (cause it gets cold and everybody needs to isolate his/her house anyways…) There is no sea where I live (it’s Austria actually). I just need to know if anybody has already done this at home or if I have to test out everything for myself. Pictures would help me a lot since understanding techtalk in english is rather hard for me. I am not looking for a high performance board (as my surfing isn’t really top as you can imagine…) something like a rather thick round board split in two parts would be fine. Doesn’t need to be light either…only portable [smile]) thanks Marcus
As long as cost is no object, anything is possible. To manufacture something accurately that can be dismantled and assembled, and be structurally sound, is more than the average boardmaker can do. I’ve done it with 5 metre wings, but the cost was just a little outrageous. I’m glad I was getting paid to do it.
well…cost is the main drive behind the thing (I want to save on airline fees and travel easier) but OTOH…I am not the most demanding surfer on the planet…I am only 70kg too… I got my hands on some carbone tubes (broken freestyle paddles)… aluminium tubes are no problem either… it will be epoxy anyways.
If you know a bit about structure, basic moulding and surfboards then have ago. Emphasise structure though, I wouldn’t want the board to snap under the pressure of my first wave at an idylic location. And I’m only 60kg. Have fun. I’ll be interested to hear of your success.
I will give it a try soon… only…does anybody know more details about the pope bisect? apparently his earlier boards didn’t work out quite well. I want to built mine out of blue foam and epoxy… Maybe somebody has the dimensions of the aluminium tubes pope uses? thicknes, lengt and diameter? When he splits built boards does he integrate some more strukture like ribs or anything into the halfs? Or will glueing the outer tube in the foam (and a base rip on the joint) work? Maybe use two tubes? Maybe I should first make the connection between the two halfes and when it’s good start shaping the board… cheers Marcus
Good idea, do all the connection work before shaping. If you are making the main joining beams on or around the stringer make sure it is solidly connected to the stringer, both sides would be good, with perhaps some smaller alignment joints at the rail. The wings we made were hollow with ribs, all the strength is in the main beam. Don’t know whether it’s any help but on the centre of a 5 metre wing, two spans of 2.5m, the beam join overlap was about 300mm. Good luck, I wish I was you at the moment, sounds like a really fun project. Greg.
something like this http://fluid.kajakworld.at/zeug/baord.jpg was on my mind… but maybe I don’t need a stringer, it is going to be epoxy anyways. How would I get all this strukture into the foam? cutting the foam open, putting everything in and then start chaping doesn’t sound too good…I would have all the expoy between parts which would make shaping a lot harder. Maybe only 2 tubes with a base rib wout be sufficiant? Building a second rib in the board is another complicated task, I would have to cut the blank again. Most force will be on the joint and the tubes meeting the first rib anyways… I should be enough to put the tubes about 20cm in every half. (how would Pope introduce a second rib in a retrofittet board?) I would cut out the baserip, glue in the tubes, heat them up and shove them into the halfs and then glue them in the new holes with some epoxy and microballons. my final thoughs (add if you fell I am wrong) blue foam, no stringer, two tubes (about a qarter from the middle each), two base ribs and some kind of hinge to attache the halfes after the board is finished. Where can I find the patent for the pope boards online? maybe there are some drawings included… I’d love to invite you over for building… [smile]) cheers Marcus 
The look of the diagram is good, but I would like to point out my reservations. I’m just trying to give constructive critisism, hope that’s okay. I like the foam you are using, and epoxy can overide the use of a stringer. But this is not a full length structure, so the pressures on the joining tubes and ribs is pretty critical. 200mm either side of the joint sounds sufficient, but if it were me I would be connecting those tubes to the deck and bottom skins with some sort of connecting rib section, or at least something that won’t compress easily, high density foam or something. This should also extend beyond the end of the tubes, just to relieve the stress wider. If you can incorporate these into the foam before shaping it would be good. I know it might make shaping a little more difficult, but the end product would be much more structurally sound. Do you plan on glassing the full board as one, and then cutting and integrating the open joins, or what? Manufacturing and installing the full tube/rib section before shaping would ensure perfect tube alignment and board shape alignment if done this way. I’m in Colorado at the moment, so I doubt I can help first hand, although I’d like to. When you decide what you are going to do, or have more questions, drop another post here. If you want we could email. Hope this helps. Greg.
The look of the diagram is good, but I would like to point out my >reservations. I’m just trying to give constructive critisism, hope that’s >okay. Thats EXACLY what I am looking for.>>>I like the foam you are using, and epoxy can overide the use of a stringer. >But this is not a full length structure, so the pressures on the joining >tubes and ribs is pretty critical. 200mm either side of the joint sounds >sufficient, but if it were me I would be connecting those tubes to the deck >and bottom skins with some sort of connecting rib section, or at least >something that won’t compress easily, high density foam or something. This >should also extend beyond the end of the tubes, just to relieve the stress >wider. >If you can incorporate these into the foam before shaping it would be good. >I know it might make shaping a little more difficult, but the end product >would be much more structurally sound. Shaping lower and higher density foam in one peace is what I want to avoid most. Then I’d rather shape the full board first and cut out a 300mm*800mm foam block from the middle to built my strukture into this and glue the whole block including the tubes and link tubes back in…when everything is alligned I can cut the foam to the edges and start glassing the whole thing in one process. This way I don’t have to shape over ribs and difficult foam. It also means 400mm solid strukture in every half. Might even be overkill for a max 8’ epoxy minimali or eggshape? The form is the next thing I have to decide on, this is going to be an even harder struggle…any ideas? [smile]) Pope might have some kind of ready module and routs out foam of a tiled board to glue in his thing…but routing out a precise peace from the glassed hull might turns out quite impossible and the endresult is no different to my way. 2 >Do you plan on glassing the full board as one, and then cutting and >integrating the open joins, or what? Manufacturing and installing the full >tube/rib section before shaping would ensure perfect tube alignment and board >shape alignment if done this way. First I planed to put in the connection first…but the way I described above seems better to me.>>>I’m in Colorado at the moment, so I doubt I can help first hand, although I’d >like to. When you decide what you are going to do, or have more questions, >drop another post here. If you want we could email. Joining me was just a joke…remember, I am in Austria (not Australia) just 600km away from the next ocean…but munichs river waves are only 300km to go…and with 29.90€ airline tickets and a splitboard I will spent more weekends in Biaritz [wink]) We can mail if you want (heavyweather@gmx.at) and I will post the results on the board when I am done, but maybe somebody else wants to join brains and give some input. regards Marcus
instead of tubes how about having a structure looking similar to tapered star pegs… i agree with greg about fixing it to the skin of the board too http://www.feraldave.com/sprays.htm 
Hey Marcus, sounds like you are well on the way to getting it done, both in your head and with your hands. Lucky I didn’t take a guess at your nationality, I would have been way off. Having not surfed for a while I definitely get inspiration from people like you. I’m glad you have found surfing and boardmaking, and I hope you enjoy the experience as much as we all do. Sounds like you have some previous composite experience. The only other manufacturing advice I could give is to be neat and thorough. And obviously be as accurate as you can with the shaping and glassing, particularly where blending the strength to the form. Good luck and post your future developments here, I’m sure I am not the only person who is interested to see how it turns out. Greg.
I have been thinking about this question with an emphasis on ease of alignment and such. I believe you could make it much simpler. Those tube-like assemblies would just be a monster to get aligned without tons of time and effort. What if the board halves were joined with what amounts to a couple of long stringers with cylindrical uprights (from deck to bottom) on each end. You need most of your strength to keep the board from buckling, so you don’t need to worry as much about side to side strength. Plus you could make the assemblies extend as far fore and aft as you see fit to improve rigidity or ease construction. It would be easy to do with lengthwise routed slots, joined by two bores with the fabbed up channel/hole assembly (carbon?) epoxied in place before bisecting. You would probably put one on each side of the centerline. The pieces to fit in the channels would then slip into the slots to both resist buckling and hold the halves to one another longitudinally. It would sort of be two dogbones holding it together if viewed from the deck or bottom. Of course there’d be some difficulty with the butt joint where the halves joined, and I believe you’d want some kind of segmented semi-bulkhead at the join. It might be worth cutting clean through the entire board, then milling out the foam for a given depth on either side of the join, scribing to shape and cutting out a solid, flat piece of material for each void, and epoxying them in place flush. You could probably just join everything up for the final glue-up with some wax paper in between the adjacent bulkhead faces at the join and mop up the mess on the outside before it sets. I should sketch this up as ably as in the earlier post, but it’s after work, I’m lazy, and I wouldn’t want to be drafting under the influence. [hiccup] Hope you get the picture I’m trying to describe and good luck!
Good to hear some other input Churchill. You mention the difficulty of aligning the tubes. This is not difficult at all when the above mentioned tubes are inserted and integrated as one piece, before the board is cut in two. Actually it guarantees perfect alignment on assembly with a very simple tube connection. As I understand it, this is the way Marcus plans on doing it, please correct me if I’m wrong Marcus. Early prototype wing sections I worked on used the tube principle, and for limited production prototypes, not unlike this project, was very effective and time, weight and cost efficient. I am not an engineer and will never claim to be, I’ve just had lots of practical, hands-on experience. I’m very open to logical, progressive suggestion. Look forward to hearing more from everyone. I hope none of you are engineers. In my experience, if you want something complicated and difficult to manufacture, ask an engineer to design it!!! Sorry, joke only…don’t start abusing me!!! Greg.