Now that, that is *absolutely* the way to do this :-) Good stuff! And, yes, so satisfying. I love how much better we're getting at this!
Vinay On Tue, Jul 26, 2011 at 4:52 PM, Steve Upstill <[email protected]> wrote: > I won't argue one way or another on the beveling issue, but I will > counterpoint your experience with mine: I used a skilsaw with a nice long > blade, which cut through the polyiso like butter. Since you have to cut a > straight line anyway, it was only marginally more effort to set the angle on > the saw and go that way. The head-scratching and equivocation about where to > put the bevels was MUCH more overhead. On my second yurt, we used a tablesaw, > which I'm kind of keen to do again. > > ...and I echo your experience about having everything fit together: AAAHHH!!! > > Cheers, > Steve > -- > [T]he unreasonable success of mathematics in the natural sciences... > is a wonderful gift which we neither understand nor deserve. > -- Eugene Wigner > > > On Jul 26, 2011, at 1:56 AM, Vinay Gupta (Hexayurt Shelter Project) wrote: > >> Extremely useful, Steve, thank you. If that bears out and all works, >> we should put this email on the Wiki for people who want to go down >> the bevel route. >> >> I've gotta say that the time I manually beveled several hexayurts >> using a craft knife and a wooden guide was about the worst of hexayurt >> construction - massive amounts of irritating fiberglass dust, >> constantly resharpening the craft knife on a little sharpener (one of >> the little pocket jobs with two crossed ceramic rods) and so on. >> >> Then I put the hexayurts together, and they fitted like injection >> moulded plastic parts: practically *clicked* together. But the >> process, with the tooling and expertise I had at the time (this is >> 2006) just wasn't worth it. Satisfying results, somewhat stronger, >> probably, but not enough to be worth recommending as the standard >> approach. In general I've tended to advise the least work, least risk >> hexayurt, and now we've got a wider community of practice and a lot >> more expertise available (i.e. it doesn't all have to fit into *my* >> head any more) I'm glad to see bevels and the H13 and possibly a big >> dome etc. all coming back into play as options for the more >> technically ambitious builder. >> >> Do take pictures and blog/post/document. It's how people learn. Video, >> too, even low quality video, is incredibly useful for propagating >> ideas, so if you can, shoot some too! >> >> Thanks for sharing the work, >> >> Vinay >> >> On Tue, Jul 26, 2011 at 6:31 AM, Steve Upstill <[email protected]> wrote: >>> I just dug out this recipe for how exactly to cut the panels of an H12 >>> hexayurt. On my second go-round I still did a bit of head-scratching and >>> hemming and hawing and STILL had to redo some of my cuts, so I resolved to >>> make it all explicit. This takes you through making the cuts, then to doing >>> the taping. >>> >>> The reason I'm sending this to the group rather than posting it in a more >>> permanent place is to get someone else involved in debugging. I'm somewhat >>> concerned that the endgame (that is, taping the joints) is a) clear enough >>> and b) NOT WRONG. So, anybody care to kibbitz? >>> >>> Don't know if this will help anybody, but it's my stab at contributing to >>> the body of documentation. Take it for what it's worth. >>> >>> Cheers, >>> Steve >>> -- >>> Activity should never be confused with progress. >>> -- Peter Allport >>> >>> ORIENTATION >>> >>> You're going to be building a hexayurt from twelve 4 x 8 foot panels. Six >>> of them will stand up on the ground (short edge up) to form a hexagonal >>> wall. The roof will be formed from six triangles that are 8 feet at the >>> base. You get these by cutting the other six panels diagonally into right >>> triangles, then joining them on their 8' edges to form six isoceles >>> triangles. When these sit on top of the wall, they come together at a point >>> to form a hexagonal cone. >>> >>> >>> BEVELLING THEORY >>> >>> The ideal surface we are shooting for has walls that are exactly 4x8 in >>> size. Since our walls have thickness, the panels need to be bevelled, so >>> that the thickness of the walls proceeds inward from this ideal surface. >>> Similarly for the ceiling panels. If you remember that the bevels are >>> always "inside" the ideal surface, it makes understanding things a little >>> easier. In fact, here's a rule: the INSIDE surface of the panels will >>> always get the most cut out of it with the bevel. The OUTSIDE surface >>> shouldn't be cut by the bevel at all. The bevel should make a sharp corner >>> exactly at the edge of the outside surface. >>> >>> CUTTING >>> The walls are easy: take six panels and bevel ONE LONG SIDE AND BOTH SHORT >>> SIDES on a 30° bevel. THE BEVEL SHOULD GO INWARD IN THE SAME DIRECTION FOR >>> ALL THREE SIDES. Ideally, the saw kerf should all be on the edge and not >>> cut into the outside surface. You get quality points for picking wall >>> panels that have dings in the edge (especially the long edge) and bevelling >>> so that the ding gets cut away. >>> >>> The roof panels are slightly more complicated. The short edges of the >>> panels you start with--which will join the tops of the walls--will also be >>> cut at 30°. The edges where the roof triangles join--the hypoteneuse of the >>> diagonally-cut triangles--are ideally bevelled at 14.4°. Call it 15. >>> >>> >>> This is how the roof panels are cut. The darkest surfaces are the INSIDE, >>> with the bevel cut into them. The lightest surfaces are the original edges. >>> The medium-gray surfaces are the cut bevel. >>> >>> 1) Bevel both short edges of all six panels to 30°. Once again, make sure >>> that the bevels cut only the inside face and the edge, leaving the outside >>> face intact. >>> >>> 2) This is important: Divide the panels into two sets of three. Mark the >>> OUTSIDE surface of the first three with a diagonal line that runs from >>> right to left. REVERSE THIS FOR THE OTHER THREE: mark the outside surface >>> with a diagonal running from left to right. Now cut all six panels along >>> the line. Quality points for cutting them right down the middle so that >>> each half loses the same amount. (NB: if it's not clear to you why you have >>> to cut three in one direction and three in the other, lay six panels out on >>> the ground abutting along their long edges. Now conceptually join them at >>> their edges, then imagine how to cut five isosceles triangles out in such a >>> way as to leave one right triangle from each end to form the sixth. See how >>> the diagonals alternate from one sheet to the next?) >>> >>> 3) Bevel the diagonals to 15°. Again, only the inside surface gets cut, >>> leaving the outside surfaces as right triangles exactly 4 and 8 feet on a >>> leg (minus the diagonal kerf). At this point it wouldn't hurt to spray a >>> bit of paint or otherwise mark the inside (say) surfaces of all your >>> pieces. It's fairly obvious what the inside of the wall panels is, but it's >>> not at all obvious what the inside surface of the roof pieces is, and you >>> CAN go astray in the next steps, so make it easier on yourself and mark >>> them. >>> >>> Now you're ready to assemble the walls and roof. You've got eighteen >>> panels--six rectangles and twelve triangles--with, among them, 60 exposed, >>> MOOP-y polyiso edges, so get to work taping those up. >>> >>> Now that you've got a crapload of pieces with no exposed polyiso, take a >>> break and ponder on joining the wall panels: your goal, in hinging two >>> panels together, is to make sure that when the joint/hinge is formed, the >>> two-panel edge that runs across the join is flat (no "jump" at the joint >>> between panels) and straight (it doesn't deflect at the joint). These are >>> the two factors that make the yurt dodgy to assemble, and there is some >>> "wiggle room" to control, so you want to get those right. Best to do that >>> by backing this transverse edge up against a straight edge or surface while >>> taping. >>> >>> Here's what you need to know about making a folding yurt: if you imagine >>> the thing assembled, then going around the circumference from one panel to >>> another, you have to ALTERNATE putting the hinge on the inside and the >>> outside. If you do this rigorously--for both the wall pieces and the roof >>> pieces--you can hinge all six wall panels into a single folding stack, and >>> the roof triangles into two such stacks. The reason you want the roof >>> panels in two pieces is to fold them into two right-triangular bundles that >>> you can lay next to each other in a rectangle (think about it). Keep your >>> head about you, though: if you expect them to nest perfectly for shipping >>> in a perfect rectangular bundle, you need to build the individual isosceles >>> roof triangles--on the edge that joins unbeveled edges straight down the >>> middle--three hinged/taped on the inside and three on the outside. >>> >>> You now know what you need to know to assemble the walls. (Need I mention >>> that the unbeveled edges need to be all lined up when you're done? That's >>> the base, you know...) Go forth and tape: come back when you emerge with a >>> single, satisfying, end-hinged stack of 4x8 panels that all sit on the flat >>> side. >>> >>> Now, the roof: Note that each of the three original, rectangular panels >>> that turned into one your two roof sets (three with left-to-right >>> diagonals, three with right-to-left, remember) produces two identical right >>> triangles, so you now have two sets of six. Pair them up, one triangle from >>> each set, and join them along their long, unbevelled edges to form >>> isosceles triangles with an 8' base (2 of 4' each, right?) and the kerfs >>> around the outside going inward--or outward--as long as each pair is >>> consistent. MAKE SURE THAT YOU'RE JOINING INSIDE FACES TO INSIDE FACES--or, >>> equivalently, that the bevels all go inward. That still leaves you free to >>> choose which side to tape: again, for folding purposes, three of these >>> joints should be taped on the inside and three on the outside. You can then >>> take three like-hinged (inside or outside) triangles and tape THEM together >>> on the OTHER side: the three that are taped on the inside will join >>> together with outside hinges, and vice versa. VOILA! two sets of six right >>> triangles that fold up to perfectly nest to form a rectangular bundle. >>> >>> Now, take your bundles and your tarp to a local parking lot or something >>> and practice putting it together. Not only does this debug your execution >>> of all the above, it gives you some practice that will come in handy on the >>> Playa. Handy suggestion: when the building is put up, locate it >>> appropriately on the tarp, and when you're happy with it take a magic >>> marker and draw where the corners go. >>> >>> Finally, two more tips: if you intend to run your fabulous, strong, 6" >>> bidirectional filament tape up and over your yurt, you will find it very >>> difficult to do. These buildings are not small, and they're taller than you >>> are by quite a bit. I had a bit of trouble the first year, and my plan for >>> the second year (undebugged, frankly), is to get two paint rollers (just >>> the wire-frame things that the actual rollers fit on, not the rollers >>> themselves) and some long extensions for manipulating the tape rolls over >>> the top of the yurt. >>> >>> The second tip concerns teardown: ripping the tape off your roof can be a >>> real hassle (see previous paragraph). But if you lay some, say, 50-lb. >>> fishing monofilament in the joints that you're going to tape, making sure >>> you can get to it afterward and that it's sticking through the bifi, then >>> you can use it to CUT your bifi exactly where it needs to be cut for >>> disassembly. >>> >>> There ya go. I hope I got it all right. >>> >>> Cheers, >>> Steve >>> >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "hexayurt" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]. >>> For more options, visit this group at >>> http://groups.google.com/group/hexayurt?hl=en. >>> >>> >>> >> >> >> >> -- >> Vinay Gupta >> Free Science and Engineering in the Global Public Interest >> >> http://hexayurt.com - free/open next generation human sheltering >> http://hexayurt.com/plan - the whole systems, big picture vision >> >> "In the midst of winter, I finally learned that there was in me an >> invincible summer" - Albert Camus >> >> Twitter/Skype/Gizmo/Gtalk/AIM: hexayurt >> UK Cell : +44 (0) 7500 895568 / USA VOIP (+1) 775-743-1851 >> >> -- >> You received this message because you are subscribed to the Google Groups >> "hexayurt" group. >> To post to this group, send email to [email protected]. >> To unsubscribe from this group, send email to >> [email protected]. >> For more options, visit this group at >> http://groups.google.com/group/hexayurt?hl=en. >> > > -- > You received this message because you are subscribed to the Google Groups > "hexayurt" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/hexayurt?hl=en. > > -- Vinay Gupta Free Science and Engineering in the Global Public Interest http://hexayurt.com - free/open next generation human sheltering http://hexayurt.com/plan - the whole systems, big picture vision "In the midst of winter, I finally learned that there was in me an invincible summer" - Albert Camus Twitter/Skype/Gizmo/Gtalk/AIM: hexayurt UK Cell : +44 (0) 7500 895568 / USA VOIP (+1) 775-743-1851 -- You received this message because you are subscribed to the Google Groups "hexayurt" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/hexayurt?hl=en.
