2009-12-26

composite tech for velo'shell


4.6:

. long clear fairings get VERY hot .
. the reason for the valley down the middle
is so you can see despite having
a leg covering while leaning back .
. minimizing knee bend (maximizing ankle work)
will help visibility too .
. for the main frame, I use PVC tubing:
flexible to allow some 'give' for potholes
. bent using a heat gun:
heat small sections and use a jig .

1. In the yellow pages, look under plastics.
Any sign making supplies shop
will carry coroplast,
but charge a premium for it.
2. after an election,
check for large signs being tossed
in the dumpsters of the losing candidates
3. Foam board at Staples and Office Max
(foam core with plastic front and rear panels)
. stiffer than coroplast; Expensive, but sturdy.
4.6: construction ideas

. I used wire rope clamps
to secure the ends of the aluminum wire to make a hoop
. I didn't use a jig to make the hoops
and later wished I had.

(Most coroplast is 4mm,
and is more difficult to work with .)
4.7: proj.mobi/dog.guard/sum of recent web:
. facebook coro'shell site has links? they weren't obvious .
best new tech ideas:
. alum clothesline for ribbing,
and bolted square 2"alum to flat angles .

4.11: tech.mobi/aluminum contouring:
. one way to get aluminum to bend into curves like a boat
is to use bundles of thinner pieces,
like the ones in the screen kit
4.22:
. when they are bound with string many times,
they will bend without kinking or wrinkling .

4.11: mobi/trike/xt fairing:
. the small lexan fairing would be a good base
for attaching fiberglass rods,
or the screen kit beams laminated .
. walmart online may show cheap tents
for extending the strong xt .

fairing supplies(eu):

. polystyrene as core material
Polystyrene comes in large blocks
and is normally used to form large structures
such as wings, control surfaces, etc.
If you are building a plans-built airplane
you will build a large portion out of this material.
Polystyrene can be cut with a knife, saw,
or "hot-wired" into the shape of an airfoil.
You can find plans for a "hot-wire" device
in the Rutan booklet
Mouldless Composite Sandwich Homebuilt Aircraft Construction
available from supply companies.
. on being informed that I was building an aircraft,
Indspec Chemical Corp. refused to sell me
any glue other than Penacolite Adhesive G-1131
. not all blind rivets are pop rivets .

something to help build a tent

A one-man tunnel tent
Two all-around zippers allow a
middle part to be opened.
The zippers are made waterproof
by specially designed storm flaps.
The integral mosquito net
can be closed separately.
Five loops on the back
hold the insulating mat in place.
We manufacture a wide range of
patented Tensegrity and Geodesic structures
using our own tarp fasteners, "Grip Clips."
All Shelter Systems' structures are "shingled,"
with the panels overlapping each other
to make a totally waterproof
and yet breathable shelter.
. made with a strong, tear-resistant fabric
and non-puncturing tarp fasteners.
The poles of the dome are made of PVC, a thermo plastic,
which gets stiffer with the cold.
Poles may be kept warm by
wrapping them in a blanket
with large bottles of boiling water.

4.12: tech.mobi/beam connectors:

. the way to connect aluminum beams geodesically
is drill the ends
and sew them with metal wire for pull
and then wrap the joint with parachute cord,
or other rope like nylon .
. then glob the rope together
by smearing it construction caulking .
. since the beams can be joined at any angle
in any number,
this can form a web of any shape .

. another form of beam lamination or sandwiching
is when the layers come from various directions,
so that where there is a joint,
one vector is being attached from both sides
by another vector .

4.22: web.mobi/shell/parts suppliers:
tents and flag poles!

GPX 4-person Backpacking Dome Ten
flag poles are another local
. by using a superflex pole (fiberglass)
the sides poles can be bowed apart
by a top pole that fits in a pocket sewed to both side poles .
. these pockets look are T shaped,
with the top of the T sewed around the side poles .
. this'll give me a cheap source of many fiberglass rods,
so the velo'shell can be kick-tuff!

6ft x 1/4" white fiberglass rod e140037
/ $2.40 ea + (Oversized Shipping)
Bike Flag Bracket:
Silver plated stamped steel e140038 / $1.80
-- these brackets can hold the rods in ways that are either removable
or can be constructed modularly:
here is a rod pocket that can be bolted to other things,
strong where strength is sorely needed .
oversized shipping costs:
For small products we can ship by USPS using Priority Mail ONLY.
Up to 2 lbs. $11.25
each extra lbs. $.75
Pole 6' to 8' $24.00
each extra pole $1.00
. you'll want to ask how much each pole costs,
for 10 poles the shipping is
45.25/10 = 4.52 per pole;
so the real cost is 7 per pole ok .

. a strong hollow tube will be easy to connect by drilled holes
$23.7 per 10ft x 1"(1/8 wall)
Can be used with flexible fittings (tube fitting section).
UV stabilized, can be used outside.
Item is priced per foot;
sold in 8' intervals only.
ABS is foam core and more flexible than PVC
so it will warp in the sun.
[. maybe it would do ok with reflectix shell over it?]
PVC is easy to work with in the same manner as ABS,
but if you buy foam core, you will have the same problems.
You can buy PVC in solid core.
If you don't use the cleaner, the joints will come apart.
stopped using ABS here over 30 years ago.
PVC is stronger and holds up better then ABS.
. not only will it warp, but it also changes
length with temperature more than metals .
. they say to be sure you get a good grade (see markings)
so perhaps tampa bay felt cheated by fakes .
. never thread the abs?
it backs your threads with nothign but foam;
reminds me that drilling foam core
may be another source of weakness .
could drill larger than needed,
and make an epoxy neck .

Compositech (3830 E 44th St Ste 538, 85713 )
(520) 584-8780
Harrington Ind Plastics Inc (4141 E Tennessee St Ste 137, 85714)
(520) 745-8433
Fiber Tech USA Llc (1517 N Wilmot Rd Ste 105, 85712)
(520) 546-7892
astm D2661 Specification for Acrylonitrile-Butadiene-Styrene (ABS)
Schedule 40 Plastic Drain, Waste, and Vent Pipe and Fittings

Aluminum slip-on pipe fittings
secured to pipe with a set screw .
Aluminum Schedule 40 Pipe, 3/4" ft/$5.35
Aluminum Bundle - 6 of 6', 1" /$157.22
Aluminum Bundle - 6 of 6', 1-1/4" /$193.30
Aluminum Bundle - 6 of 6', 1-1/2" / $221.65
Kee Klamp: Galvanized steel slip-on pipe fittings.

walmart` fiberglass rods
4.24: aq.gear/walmart#kolb&speedway:
4 camp pads /$5.88 -- for shell
wire galvanized yoursymmetry.com`14guage 100ft/$3.47
8 fiberglass poles, 6ft with safety flags /$4.96
4.25: sci.gear/mobi/flag.pole`adhesion:
. how is flag on pole?
fabric pocket glued on, and flag sewed to pocket .
. also notice the metal clip is pounded into place
so it stays on by a compression fit -- the fiberglass is tough .

4.23: hub caps: [obs except composite ideas]
. the hubs can be cut from high-density foam
and with the scraps of foam,
strips of these can be used as backing
like 2ndary washers, so that each cap
is held into place by 3 points,
where each point is a strip and a region of hub,
sandwiching 1..3 spokes .
. then paint dayglo orange
. to complicate things,
use fabric to cover the screws;
sew on a fabric from the radius
up near the screw locations,
then finish off with some spray-on adhesive .
. the paint will then cover the threads and gloss the fabric .
4.27: mobi/trike/hubs/alum or .com:
. hubs can be reinforced with aluminum flashing over hub
may also be commercial hubcaps for aerodynamics .
4.27: trike/hub`caps:
. hubs are complicated by quick release doesn't rotate
so hub has to clear it,
. the foam can be like a doughnut,
with its hole filled by aluminum flashing circle
that can have tabs
that are bent down and then out again
to fit snugly within the foam hole .

4.30: gear/composites/rattle-free hinge:
. could make a rattle-free hinge by
using rope binding wo matrix .

4.30: proj.trike/shell design/ [safety tip]
rods and adhesives have silicates:
. rods and adhesives have silicates
{epoxy use, fiberglass-cutting} needs the air.filter
-- both involve epoxy(silicates).

proj.trike/shell design/knots:
. this reminds of a boyscout trick,
I should check a manual similar to theirs
for more tech with tied branches:
use 3 tied poles to form a
pole with a knotch at the end .
. that knotched pole is bound to the faring`horz'tube,
the knotches are bound to the shell`s top poles .


composites/overview

mobi/trike`shell/materials selection:
fiber-matrix
5.12: composite tech:
. here is foam but used as a mold for fiber-epoxy,
Zote foam from Mark Mueller at Windwrap Fairings
. he used contact cement on zotefoam to itself and to velcro .

5.23: foam
. could use art`gift/apt`bedroom`floor.mat
as stronger version of shell than the camping mat .

5.28: foam/stays round:
. the roundness of the shell around the wheel wells
can come from the shell if something stiff is used as the skin,
such as the camping mats .

6.5:
. in addition to tent fly, try fabric store .
rip-stop nylon fabric

8.30: todo.gear/composites/foam shade:
. mobi foam may need cover from sun
see kite place for carbonate finish sheets,
and kevlar thread .-- see how this is uv protected .

tech.gear/composites/rod-structuring

5.3: pull.ropes:
. instead of relying on shear-grip alone,
when doing rod-composite structures,
also use rope along the length of the rods,
as is used for holding the sanctum together;
eg, when making an H-shape,
you would run rope along the horz.rod,
tying the two verts together .
5.6:
. when the joints are being bundled by a composite,
there will be several layers;
and the pull.ropes can be applied between the 2nd and 3rd layers
-- atleast it shouldn't be under the first layer,
because it would get in the way of the composite making the most
densely fibrous contact possible to the rod .
5.15: pull.ropes for bows:
. string comes up to rod pocket into a seam
like when a drawstring is closing a pouch
. how is rod`pullstring following the curved rod of a bow?
the strongest and easiest is to bring string to both pockets;
then wind a double helix around the rod .
. to be modular, keep a metal ring between pocket and pull.string
perhaps fashioned from galv'wire .
[23: . but a pocket will give the string more support, less wear .]
. alt'ly,
a piece of strap is folded to form both a pocket and double loop
then a loop for each helix
then make pull strings wrap around the pocket to reinforce its stitching .

5.25: pull.ropes/strategic placement:
. both pull.ropes should be in both loops to pull them evenly .
[5.28: they should be symmetrical,
but the can go through just one loop .]

5.25: pull.ropes/loop reinforcement:
. to reinforce the pull.rope`loop, keeping them open,
even after bundling T-joint with fiber-epoxy,
leave in each loop a bike brake cable housing
(or if need larger for both pull.ropes to fit,
then use some rubber hose from tire pump)
. the housing may help keep the fibers from cutting eachother .

5.6:
. keep in mind that epoxy is brittle like aluminum,
so it should only be involved in situations where flexing is minimized;
that's why, altho' aluminum is stronger per weight than steel,
this is so only in tubes that are of larger diameters,
offering greater triangulatory resistance;
so,
you don't want to try making a filler out of very thin rods:
keep the compositing action near the joints
where thickness can be built up relative to the surface area .
5.12:
. to minimize dependence on testing epoxy strength,
the primary strength should come from the stitching
like a tent holds poles together .
. the epoxy will be there just to protect the threads from wear .

5.25: overlapping rods
. when overlapping poles to make an extension
and using a composite binding (rope with epoxy or caulk)
then reduction of wiggle room could be sufficiently done
simply by addition of a 3rd rod to the bundle .
5.30:
. 2 rods can fit in one al'beam at the same time;
so, they can be like female-female connectors .
5.31:
. while the pull.ropes will keep overlapping rods from lengthening,
the overlap-joint must somehow prevent shortening .
. when using the one al'beam as a female-female connector,
the way to do this is to make the al'beam longer than the overlap,
so that each end of the al'beam will allow only one rod .
. the pinched part is wrapped in fiber-matrix
both to prevent the al'beam ends from being a cutting hazard,
and to strengthen the fragile crimped aluminum .

5.31: overlapping rods/nylon.strap:
. is there some nylon.strap-version of an overlap-joint:
. T-joints (the kind using strings) on both ends of both rods,
could use their pull.ropes to provide both the usual pull-apart resistance,
and a push resistance: the ends that are near the overlap,
their pull.rope loops would share a rope .
. a joint specialized for overlaps could be like this:
a 3" strap uses 1" loop back to form a pocket,
and then another 1" strap is sewed on the part of the longer strap
where there is no pocket .
. the short side of the pocket should include a pull.rope loop .
. a nylon.strap joint could also be useful in conjunction with an
al'beam fe-fe connection by filling this sewed strap piece with matrix
instead winding a matrix-slathered string around the al'beam ends .


5.3: gear/composites/shell-to-rod attachment:

5.24:
. the shell is partially nylon like a tent for toughness,
and then also some sort of insulation for reflecting desert heat .
. this insulation can be either foam mats
(as for placing under sleeping bags, or at a stand-up station)
or it can be reflectix, which is not as tough, but great at insulating .
. the foam can be arranged like plates on a rhino,
then along the cracks of these plates are wide bands of nylon fabric;
this gives a lot of surface for many connections .
5.3:
. the mat is sewed to cloth with stitches 1/2inch apart
-- the same as its thickness .

5.24:
. there is not eno' strength along the rod to epoxify the flange .
-- that fact nixes this idea:
5.3: "(
. the insulation is attached to fiberglass rods by a composite flange:
. the general flange pattern is to form a pocket of several epoxied layers
on both sides of the the rod,
perhaps also gluing the rod to the fabric,
but leaving edges unglued for easy sewing to the mat or other flanges .
-- if smearing the entire pocket with epoxy to strengthen the threads
then the flange could not easily be reused
in case the shell or was damaged or the threads broken .
) .

5.24:
. attaching foam to anything by stitching is very labor intensive;
that fact nixes an any idea that shell should get some of it strength
from triangulating the rigidity of the foam;
eg:
5.3:
. "(. the rear cone [mobi/trike`shell/tailbox] can get strength from
the rigidity of its own camping mat panels .
)

5.6: rod-structuring/application of the matrix:

5.24:
. for some rod-to-rod connections it is better to use fiber-epoxy
than to sew pockets together;
this is where technique of applying the epoxy
can be critical to the strength of the joint .
5.6:
. once the epoxy or other matrix is mixed,
simply wad strips or strings of fiber into the mix,
then after working it in,
slide down fiber with pinched fingers to wring out the excess,
and apply to joints that are already held together with a wire tie .
. practice ahead of time winding the string in place,
keeping in mind that it has to be very tight,
so it is the fiber that is filling up most of the volume,
not your matrix (the epoxy) .
. pre-knot the end of the string,
and then when the winding is done,
use that knot to catch a clamp to weight the end down .
5.12:
. the test can be part of the manufacture
by making pockets that tightly fit pole via sewing
and pole is slathered with epoxy to see how holds to fabric,
then pockets are sewn together .
-- re: 5.3: try the epoxy on practice parts first .

rod & beam structuring:
5.12:
. the design is extensible and repairable in layers
. the core is a flimsy pole,
while stiffening can be done incrementally by
splinting on layers of aluminum.beam
. if an aluminum.beam is bent then it may be floppy
but the shell will still be usable until home for repairs .
5.24:
. a network of aluminum.beam is also useful for
minimizing the effects of a cutting gash
such as when caught on something while in motion
or during a vandalism attempt .
. when a network joint can be floppy
it can be constructed by stapling the ends together
with a twisted ring of wire .
. if stiffness is needed, then the joint can be bolted,
and/or reinforced with epoxy-fiber .

5.25: aluminum.beam triples:
. the aluminum beams can be triple bundled
to form h-structs at their ends;
ie, during a T-struct with the bottom being a triple,
and the top being a rod,
the concavity at the end of the triple will fit around the rod .
. the triple can be stapled around a rod by wire loop,
then goop with flashing caulk
then cover goop wih bundles of rope loops around the triple .
. picture the triple with the rod taking the place of the middle beam
about a centimeter deep, so there is room to have
bindings around the triple on both sides of the rod .
. the staple goes through at a 1/4inch below the rod,
and also just above the rod,
the middle beam above the rod is not connected by the staple
but is there simply to provide filler to prevent collapse
during bundling of the beams above the rod .

5.27: aluminum.wire
. sculpting the fenders can be easier with the aluminum clothesline wire
. twisting wire can make random networks .
. a bit of epoxy to hold the twist on its base,
and then the whole net is kept in place by fabric sewed onto it .

5.28: sewing with string:
. sewing needle for string ?
can be done by small loop of thread holding string,
and using an awl to widen holes .

rod-structuring/nylon straps/T-joint
5.24:
. the most important pocket is holding 2 rods in a T-structure,
where the base of the T is part of a bow,
so that pocket is also got a pair of loops for the pull.ropes on the bow .
5.16:
. a T-shaped rod connection can be done with a single strap,
doubled to form 3 loops:
. form loop for rod connectiong to bow;
run the strap down the bow`s rod and then back up
to form the loop for the top pull.string;
then run the strap back up to bow`rod`end
and down the bottom side of the bow`rod,
ending the strap with a loop the bottom pull.string .
finally, the sandwich of strapping around the bow`rod is stitched shut .
5.24:
. a major design variation at this point
is whether to create a T-joint is strong eno to
keep the top from breaking and sagging,
or instead design it with the sag built-in,
so that the top rod is hanging in a loop that is tangling from the bow`tip .
. yet another version is to be both dangling
and resting in the corner formed by the bow's rod and its string:
here the same loop that holds the bow`string could hold the T-crossing rod .
5.30:
. this is an improvement on, the T-joint:
. the previous version tried to do the whole joint with just one strap;
but for getting the cross-loop near the end of the pocket,
that meant that the piece was too thick to machine-sew in some places
meaning that it took longer, and the result was loose or messy .
. the new method just uses some rope in place of the cross-pocket:
just sew a pocket with loops at the end for the pull.ropes,
but wherever you want a cross-loop, leave a couple of 1-ft ropes
that are perp to the pocket's stitching on the sides
and are inside the pocket so they get run over by the stitching .
. alt'ly or additionally,
the loops of the rope can be sticking out of the stitching,
so it has a P-shape .
. bring the ends of the rope outside the pocket
to insure that the rope got run over by the stitching multiple times .

rod-structuring/nylon straps:
5.24:
. if you did need the pocket to adhere to the rods
then one way to make sure the pocket hugs tightly during epoxy cure
is to wrap string around the drying pocket;
when that dries, then the string can be removed
and another layer of fabric-epoxy applied .
. if you have slow-curing epoxy,
then you might try doing all the layers at once .

5.15:
. the design should not allow the parts to press directly on the stitching;
eg, if you have a wide nylon band,
then you could double-fold it to make a pocket where
2 of the 3 sides are held by fabric alone rather than stitching .
5.16:
. a single 1"-wide strap fits around a pole,
to make the joints for connecting string to rod,
which is good for making a stand-alone bow;
but, consider how the joint lets the bow points attach to other rods,
in the case of the TT-struct that is extending the chair`back,
there is a perp horz' which has the same need as the pull.rope
only the sheath is larger to fit a rod .

5.24:
. at one point in the design (the top rim of the clam`bottom),
there is a need for some rods to be bound overlapping,
in order to form one long rod out of 3 shorter ones .
. this can be done without having to know how much overlap is needed,
like so:
. 2 of the rods come together at the back to form the tailbox`top,
these are then fed through the loops of the TT-struct
extending from the chair`back .
. a bow is made for the front, which has a version of bow`string in the middle,
so that rather than looking like a D,
it's as if an H had its top verts bent inward to connect with eachother .
. this can be done with a system of pull.ropes that not only keep the pockets on,
but also help keep a couple of mid-way bands suspended in place .
. with the front and rear subsystems in place,
it becomes readily apparent how much they overlap .
. the entire tear-shaped struct can be pull.roped to keep the overlaps together .

5.30: rod-structuring/nylon straps/X-joint:
. the x-joint is has no 3-sided pocket,
it's just 2 perp loops stapled together like so:
a 2" strap is viewd vert'ly;
a 1" strap is placed parallel 1/4" from the top;
the sides of them are sewn together -- to hold a vert.rod .
. the bottom edge of the 2"strap is flipped around
to be aligned with its top edge;
and then these edges are sewn together -- to hold a horz.rod .

gear/composites/rod-in-tube/pull-rope doubles as anchor.line:
5.30:
. instead of having a pull.rope joint at bottom of seat`back`s extension.rod,
attach its top pull.ropes to the bottom of seat or to some other point on trike
so that the pull rope will both keep the top`T-joint on its rod,
and also keep the rod in seat`tube .



6.15: gear/composites/metal chemistry of copper with aluminum:
. Copper is PLUS 0.34 volts OVER Hydrogen.
Aluminum is negative 1.7 volts UNDER Hydrogen,
that is 2.04 apart with Copper the anode,
therefore copper would be sacrificed to the aluminum.
However, if chlorides from salt air is around,
then the aluminum will also be corroded.
Properly sealed, preferable dichromate sealed,
aluminum is non conductive and hence zero with respect to hydrogen.

11.16: gear/composites/sewing plastic sheet:
. to sew plastic into shell or tents etc,
use foam strip as shim to reduce leak
and allow wider stitching (fewer hand-stitches) .

gear/composites/nylon.strap/overview
gear/composites/nylon.strap/pull.rope buckle:
6.5:
. make things easy to take apart
by adding a buckle into the pull ropes:
. instead of pulling end-to-end pockets,
each end`pocket is pull-roped to the loop of a buckled belt .
. buckles with adjustable straps can also make it easier to
get a good pull.rope`tension .

9.6.2: gear/composite/nylon.strap/al'beam to rod

. the al'beam triple could have a nylon.strap joint
-- easier to reproduce than fiber-matrix;
here is for one or more al'beams
that don't interlock with rod:

. make a pocket for al'beam like for the belt`loops on jeans:
the beam is like the belt in this model;
the straps are perp to the belt .
. the strap that is holding the belt loops together (the pocket strap)
has loops on either end, like the usual T-joint:
one for pull.ropes, the other for a rod .

. to interlock triple.beam with rod,
replace rod's loop with a full wrap-around -- an exact T-joint,
only the construction differs to accomodate
the beams not fitting the usual strap pocket like a rod can .
. either use wider strap's (3" as in car seatbelts)
or first sew thin straps together like this ++-++ ,
then bend in half and sew the tips of the crossbars together .

. to keep sandwich from sliding
drill beams and rivet with wire twist .

. the strap joint has to be strong eno'
to crumple al'beam before it can penetrate driver .

. when a triple beam is arranged to interlock with a rod,
drill 2 holes so that one hole is just beyond the inner beam,
and the other hole is a half inch under the first;
ie, solidly going through all 3 beams .
. putting the tie this wqy reinforces the area contacting rod .

ripstop sheet

6.5: summary:
. best is ripstop polyester with a polycarbonate resin finish.
(originally by icarex)
cheapest is blemished ripstop nylon at kite store .

. tutorial on Sewing ripstop nylon

types:

CORDURA¨
Ultra-Lightweight Woven CORDURA¨ Fabrics Made with INVISTAª
Type 335C High Tenacity Nylon
* pack cloths, ripstops, dobbysÉparachute fabric strength, ultimate lightweight
Type 480 and 485 High Tenacity Polyester
* best-in-class performance at value price
n.amer suppliers:
http://www.jennisfabrics.com/JEnnisFabrics/faq.jef#searching
http://www.emtexinc.com/
http://www.consoltex.com/pages/brands.aspx?lang=EN-CA
http://www.buschassociates.com/products.php
http://www.brookwoodcos.com/rg_division.html
http://www.bdadye.com/specifications.html
http://www.bpf-llc.com/specifications.html

fabric and thread weights:
There is the weight per area of fabric {usa: raw oz, uk: finished gsm};
-- gsm: grams per square metre --
and there is also a 'denier' ('d')
'denier' was originally grams per nine kilometres of thread.
[a high-d thread is thick or dense]
Thus we have the well-known 1000 d and 500 d Cordura fabrics,
the 210 d Packcloth,
and the 70 d tent fly fabric .
[a high-d thread with low fabric weight has a loose weave]
--
. usa's raw oz per sq.yard, means the actual weight depends on the coatings
used for durability, rainproofing, etc .

materials caveats:
. neon colors do not fare well in the sunlight
. For added UV protection in the sun,
spray fabric lightly with Armor All
(used on dashboard of car)

www.tufflight.com/icarex.html:
We seal the seams and edges for fuel proofing and durability with CA, epoxy, or Goop
. Goop can safely be thinned for brushing with laquer thinner.
5.6:
polycarbonate-toughened fabrics lose toughness when adhered with solvents.
. polycarb'fabric can be very tough on sewing machines .

3m77 is example of changing formula for lower voc content
replaces some carcinogen with acetone -- not good for same targets .
there are actually 2 3M-77 formulas - the "Classic" one that contains dimethyl ether
and the new one that contains acetone

polycarbonate sheet

gear/composites/polycarb (polycarbonate farings)

6.6:
. the faring is made of 'carb (polycarbonate)
and it's supposed to have reflectix glued to it;
but, polycarbonate loses toughness when adhered with solvents?
should rethink the use of spray-on adhesive:
maybe use caulk, esp'ly silicon? that may not stick to well to 'carb;
a greenhouse.text said it does work with al'tape and silicon,
but just as a window sealant .
GE SilPruf Silicone Sealant (Polycarbonate Compatible)
GE silicone 2, its used for aquariums and food prep areas in resturants.
(one silicone has "mineral spirits, and Xylene, is that ok?)
. don't clean with either ammonia or bleach; use soap rinsed with acid .

. some construction silicones may be ok for 'carb but not stick that well .
http://books.google.com/books?id=dSQ8cS5WXpcC&pg=PA516

. the most important thing is that the reflectix`surface be fixed,
so that the al' doesn't rub off;
in that case, the gentlest thing for the al'
is to spray-glue it to the plastic sheet,
and then staple-stitch it to the faring .
. drilling is one thing 'carb is really tolerant of .
. make the staples alligned with the wind .

. the al'tape can help both with curving the reflectix,
and attaching it to the faring`edges .

polycarbonate adhesives are formulated free of volatile organic compounds (VOC)
for better air quality and yet provide high strength bond
for polycarbonate and other thermoplastics.

. could it be painted to provide shade?
It is UV blocking already, but you can paint the inside with a plastic paint.
-- Garry :www.utahtrikes.com/ 05/26/2009 09:07:08 PM

. use of spray adhesive
8.11.7/aq.gear/ace hardware/elmer's multi-purpose spray adhesive
. the spray adhesive has many of the evils not meant for polycarb's,
but perhaps it may be used in undo-mode:
spray it on the reflectix, wait for the voc's to boil off,
then applying it to the polycarb will not be dangerous .

. to give it perm'tack, it may also be ok to spray 'carb strategically,
just as you would cut it, making holes only where the remaining web is
strongly triangulated: like an small blots every 6", about 3" from the edge .
. then again,
what if the 'carb is porous wrt to voc's?
putting just a dot on, the solvent might spread
surprisingly beyond the dot .

advice from the maker:
http://www.hobby-greenhouse.com/lexan.htm

Chemicals to avoid include:
. benzene, gasoline, acetone, and carbontetrachloride,
formulae containing petroleum based solvents (Deep Woods mosquito repellant)
etc --. 'carb can turn opaque and become brittle, losing toughness .
materials to watch:
. vinyl -- used as covers for greenhouse .

Drilling: Drill with a high-speed steel or carbide-tipped twist drill.
Drill holes slightly larger than the fastener to allow for expansion and contraction
(e.g., drill a 1/4" hole for a 3/16" screw).
Place holes at twice the fastener diameter
or 1/2" from the edge of the sheet, whichever is greater.

11.16: trike/shell/faring/uv shield:
. good way to get good fit over faring is
pieces of nylon glued and smothered with epoxy;
it's not in contact with the carbonate:
it gets stapled over reflectix .

staple stitching
gear/composites/staple stitching
6.17: summary:
. foam camping mats are light and tough;
but, the mat is too thick to machine-sew;
however, it can be easily stapled:
. 18 guage wire is 1.2mm thick, 50ft /$1.9,
http://www.acehardwareoutlet.com (sku#50598)
is a replacement for paperclip wire,
but the aluminum is a bit softer .
. staple-stitching is more convenient than hand-sewing with rope;
because, while a sewing needle for rope is not easy to come by,
staples serve as their own needles, though for most situations
you may need to use an awl or scissors point to start the hole .

. the 2 major stitching styles are:
1: the foam-wide staple grabs the foam
and then on the other side,
gets twisted with the ends of adjacent staples .
2: the hair-pin staple stradles a backer wire,
and then twists around itself .

. the use of thicker wire; eg, 14guage galvanized
(walmart/yoursymmetry.com's 100ft/3.47)
allows the design of undoable stitches:
it's stiff eno' so that you can form the ends of the stitches into
loops that can be laced with string,
or hooks that can grab string or rods .

. if staples will be eroding one of the "(fabrics) involved;
(as when a foam hub`cap is stapled to the spokes of a wheel)
then consider adding an additional layer of fabric
(as when spokes are laced with string
that the staples can twist around)

. if pieces of fabric are arranged in a way that cannot be machine-sewed,
the job of hand sewing can be replaced by stapling;
before the pieces are to be assembled,
prep them by sewing a tube of fabric along their edges
(eg, fold the fabric's edge over
and sew that fold in place)
then fill all the edge tubes with backer wire
which can be straddled by hairpin staples .

6.2: foam:

. staples on foam can be both very strong and look neat on the outside
by using the sewing mach's stitching tech:
instead of looping around the fabric,
the stitch loops around a thread on the other side .
. on the outside along where the staples will be,
is a wire that can either be run continuously
or in segments from a series of shallow wide staples .
. from the outside pushed inward are narrow deep staples,
that straddle the outer [backer] wire,
and then on the other side,
they twist around a nearby rod, beam, or spoke .

6.4: avoiding spokes:
. if concerned that the wire will erode the spokes,
then foam can be on one side with a catch-wire[*] on the outside,
and a catch-rope on the other side of the spokes .
so then long staples come in around the catch-wire,
through the foam, past the spokes,
and finally are wrapped around the catch-rope on the other side of the spokes .
(*: a backer wire, like the backer thread provided by a bobbin spool)

6.5: fabric:
. a metal grommet is the ring in a fabric that reinforces the edge,
as for lacing holes in a shoe;
. to reinforce woven fabric cheaply, use wire and the sewing.mach:
. sew loop all along the edges, ie, fold-over for a neat edge,
but do it widely, so that a wire can be sent through the loop .
. with wires on all edges, there can be staples that go around that wire,
while one prong of the staple goes through the fabric .
. both prongs then bend around something the panel is being attached to .

al'beam (aluminum composites)

gear/composites/al'beam

6.4: twin-beam triangulation:
. to curve a vert.beam around some obstacle,
have the vert spawn a diagonal on the way up,
and then a horz.beam at the top will have 2 points to attach to .

6.14: dooring:
. a door`frame and it's threshold`frame can be made from al'beams
connected by shaped wire:
the wire is shaped like a paperclip bent into a right.angle;
and also bent in such a way that it creates a friction fit
between the wire form and inside of an al'beam .
. reinforcing this formed-wire connector is a caulk filling
and/or a fabric covering .
. the hinge can be part of the formed-wire joint:
. for the joints making up the hinge`side of the threshold`frame,
one end of the wire comes out of the joint
and follows close by along the z-axis -- where the hinge should be .
. when this is done for both the near and far corners,
there can be overlap that is bound together
-- forming the core of the hinge .
. the fabric that is forming the panel of the door
can then be wrapped around this core .
. to be more modular,
a hinge`core.wire can be built into the frames of
both the door and the threshold;
and then these cores can be bound by wire spirals .
. the door can thus be repaneled independent of the hinge .

bows of fiberglass rod

gear/composites/bow
6.22: gear/composites/bow/multi-string.bow:
. with a single string, as normally defines the bow,
the bending of the rod can only occur in one way for a given size of rod:
depending on the length between the attachment points .
. the shape can be further modified by using more than one string:
mark the 4ft rod at every ft for mark#0..4,
the left string is mark#0 - mark#2,
the middle string is mark#1 - mark#3,
the right string is mark#2 - mark#4 .
. this can take the shape from "(u) towards "(o) .
. in the making of vehicle structures,
it allows a rod to be bent without having the string being in the way as much,
because the shape is more like "(C) than "(D);
eg, there can be a bow under the seat
and extending far up each side,
without requiring the driver to duck under a string .
. this multiplicity of bow strings
can be taken to a continuum
by using just one string on a bow in a sock,
so that when the string is pulled taut,
both the string and the rod are pulled into a curve .
. a discrete version of the continuous sock,
is to knot a 1...4-inch loop in the string every 6...12 inches,
then while stringing the bow, also wrap the loops around the bow
as was done with the sock .

10.28: web.mobi/trike/shell/fire-resistant fabric:

Topps Safety Apparel Inc.
P.O. Box 750, 2516 E. State Road 14 Rochester, IN 46975
Phone: (574) 223-4311 or (800) 348-2990

Flame Resistant Industrial Apparel
Fabric Content: DuPont NOMEX¨ IIIA aramid (93% NOMEX - 5% KEVLAR - 2%Carbon).
Characteristics: Inherently flame resistant anti-static fabric
engineered to reduce "nuisance" static.
Self-extinguishing, will not ignite, melt, drip or burn.

Fabric Content: INDURA¨ (100% Flame Resistant Cotton).
Characteristics: 100% cotton treated with a permanent flame resistant finish.

FIREWEAR¨ 55%FFRª (Fibrous Flame Retardant Fiber) - 45% Cotton.
The FFRª Fiber is designed to emit a noncombustible gas
through microscopic pores in the fiber when the fiber is exposed to flame.

FIREWEAR¨ FFR Fabrics are trademarks of Springs Industries, Inc.
Fabric Content: TUFFWELD¨ (60% Lenzing FRª - 40% Kevlar¨).
protection against constant weld spark spatter.

TuffWeld¨ is a registered trademark of Southern Mills, Inc.
40% PBI¨ - 60% Kevlar¨).
PBI¨ - KEVLAR¨ blended fabrics have excellent flame resistance
and are self-extinguishing. Does not burn, melt or drip.
Pbi Gold¨ is a registered trademark of Hoechst Celanese Corporation.
Topps¨ garments meet all requirements of the
NFPA 1975 Standard on Station/Work Uniforms for Fire Fighters, 1999 edition.
Topps¨ Flame Resistant Garments meet the performance requirements for
protective clothing as governed by
OSHA Rules 29 CFR, Part 1910.269
and ASTM F1506-1994.
10.29: proj.trike/shell/screen-foam composite:
. another way to prevent mold and reinforce shell
is to patch-work al'screen stapled to foam
so it better resists tearing from knives or dogs .

11.16: trike/shell/cheap vs easy-to-work materials:
. cheaper than fire-resistant plastic-board
is finding way to apply al'flashing to edges
need a crimper to make edges safe, and neat way of stapling it to the foam .

11.28: trike/shell/toughskins epoxified fabric plates on foam:
. another way to reduce vulnerability to flames and cuts
is to do a fiberglass construction in a paneled or semirigid way:
. start with tent construction,
use foam for insulation and contouring,
then use plates of epoxified fabric over that .
. paneling is like when sidewalk concrete is separated
into sections that can mov randomly without cracking randomly
-- keeps the fiberglassing tough .
. another view is the recipe for thorn-proofing jeans:
it was something like tough-as-nails, a chewy adhesive,
that would bend with the fabric .



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