This has been a long time since I last wrote this and I haven't added anything new. The links at the bottom are probably no longer available but then again.
Introduction
It is also important to emphasize that this booklet is on experiments on making components, and is not intended to be the last or only best way of doing this sort of thing, only a collection of experiments, examples, observations as well as suggestions relating to this type of work.
I wrote this booklet as a result of my own needs for more than one reason one being that I have no machine shop, both expensive and require a lot of space, and I had to find a way to have all the parts I needed to finish or start interesting projects .Add to this that I very often needed parts that wont rust or corrode and keeping weight down is not usually a loss of advantage. If you are like me you will tend to like to save money as well and if so, you will also keep lots of old parts around. Only to be annoyed by the fact that the shafting on that really nice motor wont fit that really nice pump, gearbox or what have you. Of course sometimes you need lots of one type of a special part. One of the things I like about making composite parts is that most everything doesn't need to be very rugged or heavy to hold the required precision, I even use modeling clay quite often. You may have noticed that I try not to include to much on the free information that you will get any ways when you get the catalogs or buy the resins and materials but a quick review might be a good idea to make sure you look into them.
You may be aware of how an almost all composite gasoline motor has been made with considerable weight savings as well as composite and ceramic guns but both of these uses have needed to use ceramics or metal in areas of extreme heat such as piston tops and metal liners. It seams conceivable that the do it yourself could also do this sort of thing by using precision tubing, if long term wear resistance is not a concern, in some cases even Teflon as a liner could be considered. This might mean finding precision metal rod that would fit the tubing to assure its straightness and also serve as a piston. I have mentioned some on hydraulic cylinders in this booklet. Also sports cars have used fiberglass springs with improved performance over steel springs reported for them.
Its important to keep in mind the directional strength of fibers with carbon fiber often sold with a tensile strength of 450.000 psi wile the tensile strength of the steel used in bolts is often about 125.000 psi tensile. With the much less common cutlery steel about 225.000 psi tensile with the carbon fiber much less in weight but steel is strong in all directions and that means you need at least 2 layers of carbon fiber to go in both directions when you are replacing a metal plate. This directional nature is less of a disadvantage when you are using carbon fiber reinforced rods or wherever the loading can be directional, this is where composites really outperform metals at their best.
SOME GENERAL INFORMATION FOR BEGINNERS
While it might be possible to start this hobby with only about 20.00 to 30.00 $ if all you buy is the silicone resin and either some polyurethane or epoxy in small quantities. However I don’t recommend this, as it will always end up costing you more, as extra small quantities are usually very inflated in price.
I usually do not recommend using fiberglass resins to mold your parts both
because of how it shrinks and tends to warp your molds and this is very bad
for gears. If you chose to use epoxies, try the types that are used in boat
building because they are also used with fiberglass and be poured like fiberglass
resins. Epoxy's have a tendency to be brittle but you can still get reasonably
good gears and other parts from it, with the advantage of course, that it
can also be used with all of the same reinforcements typical of fiberglass.
However with other fibers with often even better result .If you chose to
use the polyurethane’s and these also are available as 2 part mixes
similar to the epoxies. But they are not brittle and can cast gears, that
are similar to the regular plastic ones found in toys, however polyurethane
has more than one hardness available so you will find that the harder resin
might be best for gears. Use of the softer may be better for belts and rollers
and yes you can add reinforcement to this as is especially desirable for
making belts. But because of the dark color of both the Kevlar fiber and
the type of polyurethane I have worked with, "mine was black "it is difficult
to tell when anything is thoroughly saturated in resin. Polyurethane will
keep well before the containers are opened but are more difficult to store
after they are opened but their is some tricks you can try to prolong this
storage life such as purging the opened containers with nitrogen. I have
read will work, so I suppose pumping the air out of previously opened containers
might work. If your epoxies start to crystallize from storage, just putting
them in hot water will often recover the epoxy so they are easy to keep for
many years, much longer than the clamed shelf life due to this recoverability
and I have done this often with epoxy's I have kept.
SOME MORE ON MATERIALS AND STRENGTH
Aircraft aluminum 7075 the strongest alloy is about 78.000 psi and tends to be extra subject to corrosion partly because of its high zinc content.
E-glass the most common kind is 160.000 psi, S-glass is 225,000 psi
Spectra would be interesting to work with but has less ability to bond to the resin but some work has been done with treating it with plasma to get it to better bond with resins .Its about 1/3 stronger than Kevlar
Zylon or PBO appears to have twice the strength of Kevlar but I have little information on it. And I only found out about it on the Internet.
Not sure how they might ever be used in resin composites but its amazing
what is clamed for carbon nanotubes, big time extreme strength.
Kevlar is about 200.000 psi but more than one type is available, and it should become easy to note that one reason it is stronger is because its weight is so much less. This fiber is yellow, unusually hard to cut somewhat fireproof but downgraded by sunlight's ultraviolet it makes parts that have good tenacity but less compressive strength than carbon fiber. Carbon fiber is a black but easy to cut fiber and is electrically conductive but resists sunlight's damage, when it breaks it forms dangerous splinters. Douglas Fir is about 40.000 psi tensile but one needs to remember that wood is made up of many tiny tubes and as tubing forms of materials generally always add to the strength of a material, it has extra strength for that reason. Makes me wonder what advantages you could get by having micro tubes in composite rods and tubes.
Double the spacing of 2 fiberglass layers by using a foam core and the material gets nearly 4 times stronger and nearly 8 times stiffer
Stiffness is another mater. Just as its easy to visualize trying to double
the strength of a thin steel cable using a bunch of elastic bands, just after
the steel breaks the elastic bands start to show their strength and the fact
that both were able to support the same loading loses meaning. I have read
that it is differences in stiffness, which is why using fiberglass to reinforce
a wooden boat hull is less effective than you would expect. Carbon fiber
would work better for this because of its greater stiffness. Also the use
of fiberglass resin is considered a mistake on wood both because it lets
moisture through and doesn't bond all that well, but epoxy is clamed to perform
well. Sometimes thermal expansion is important and its interesting that carbon
fiber is near zero lengthwise. Woven fibers can lose a little extra strength
because of how the strands must go over and under each other rather in a
strength line, as is the case with unidirectional materials
COLLECTED TIPS AND IDEAS TO TRY
If you plan to make a mold in silicone rubber for round shafting, as I have done, it may make most sense to do a number of different sizes in one mold, to get more stiffness from a wider mold. And make sure at least one edge of your mold is precisely smooth and straight so that it will push against a straight piece of metal so you will know its also straight. The bottom of your mold must also be very flat, but because you must make this mold by pouring the silicone in from the top you would need to use a flat surface to cover your mold. To get mine very flat I usually use strips or pieces of old glass coated with mold release, as I have found some pour-able RTV silicones can stick to glass. Also it helps to make all the sides of the molds with straight pieces of metal, and all of the same height pieces. I have gotten good results from such molds and it is easiest to make them with all of the fibers going in the one direction. I do not knew at this time if wrapping at least some of the fibers around the outside might improve strength and will have to look into this and update my site later on.
I don't at this time have enough experience to say if these types of rods
may be best for some applications over using rods made by alternating the
fibers at 45 deg to each other.
My own experiments, crude as they were, didn't seam to give rods of the same
strength when wrapping the fibers at 45 deg to each other. It may be that
to gain torsional strength you must lose some lengthwise strength and vice
versa, besides making them with alternating layers was more difficult, especially
for tiny rods. While good torsional strength is attained by wrapping the
fibers at 45 deg angles in alternate layers, I don't have enough experience
to say how well this compares with metals in this use because of its greater
volume and whether or not this extra volume might be important, i.e. larger
shafts need larger bearings .
However if space is not important, and because forming a tube usually gives even better performance, you could consider wrapping the fibers around a tubing that could be removable by chemical or other means.. For example aluminum tubing is often removed by either sodium hydroxide or hydrochloric acid solution. Unlike solid rods where one can at least, occasionally get away with loading, all in one direction , I cant see making tubing without the alternating 45 deg or some other choice to prevent it from splitting into fragments, easy to imagine how flimsy a thin walled tube would be without this alternating or some other reinforcement.
I haven't yet tried all the ways of adding a bearing like surface to carbon fiber shafting as I don't think it would wear well if used in oil less bearings without a thin metal cover. So for this you could try fine tubing or gluing, a oil less bearing onto the shaft, that will fit inside of another bearing. Of course ball bearings should be good without this, and do remember to take advantage of composites directional strength advantages, as I have illustrated elsewhere.
Sometimes for inexpensive parts for applications that are not to critical, it can make more sense to make and test to destruction the part you intend to use with a simple set up you can make yourself, to see if it’s strong enough.
It might be interesting to experiment with waxes made from for example organic acids like stearic acid so that a chemical like sodium hydroxide can dissolve it. Organic acids such as stearic can be made by reacting an acid solution on a soap solutions.
Do look into jewelers wax's as these are already sold as wax rods of various diameters, modeling clay like waxes, carving waxes, casting waxes even a water soluble wax and more that are useful in all sorts of ways for temporary jigs and forms. Dental clinics also use many of these waxes also for lost wax casting. A process where wax is carved or molded into rubber molds finished up and then placed into a plaster casting. The whole thing is then baked to evaporate the wax and then the fossil like cavity is used to cast bronze, silver or gold, and yes parts as well can be made this way. A possible example of such a use would be using wax rods to assemble into what you might want for a hydraulics fitting or piece and them casting it all in resin to later melt out the wax leaving numerous tubes into the casting as needed.
Try making your own friction bearings by wrapping the shaft with wire, I would prefer if something better than copper or brass wire were available such as some alloy that is best for this application, but I really don't know. One I have treated the wire with babit as a solder thinking it could help but didn't do any tests. Its important to remember about how dissimilar metals can cause accelerated corrosion but its usually not too bad on stainless shafting but like steel, aluminum shafting is especially likely to corrode and seize.
To make a bearing in just epoxy as this has been done to mold rudder bearings for boats, grease the shaft that you are to surround with the bearing mix of epoxy and graphite. Graphite is added for the same reason its used in lubricants .I wish I knew the recommended amount and if a coarse graphite is best over the very fine powder and putty like mixes might be except able. When I mold gears I will often add graphite to the epoxy thinking it might make the gear teeth have some lubricant like properties but am unsure if this helps but I also like to use graphite as a black pigment any ways.
When making gear molds chose models that are thicker because plastic are often weaker than metal so you may want to make up for this by molding your plastic gears as thicker than needed for metal. You often see extra thickness in commercially made plastic gears designed for heavy use for this reason. I usually add milled fiberglass and milled Kevlar might be a good idea but keep it pour able to increase the strength of both the gear and its teeth.
Because it is recommended that you will need to use vacuum to remove air bubbles from the silicone mold making material before its poured. Maybe look into using old refrigerator pumps to do this, as they are really not that hard to hock up. Just follow the two thermostat wires and replace with a regular switch, obviously for this application you no longer need it to turn on only when its necessary to keep your food cold
The cheapest resin filler I have used is made from processed mud and seams to work really well. Make this by mixing the mud with water so all the larger particles can settle out, then after a short period of time pour off the water containing the smaller particles and dry and burn in a fire to oxidize all organic’s. Yes you should try the other fillers such as milled fiberglass, thixotropic silica, micro spheres, talcum powder and etc. but this one excels in cheapness if you don't mind it being heavy, brown and hard to sand.
On pigments, try if you can to get pure pigments because some of the additives that are added to keep them as liquid pastes can cause other problems or restrict the use of the pigment to only one type of resin. Unfortunately some pigments lose handling advantages if they are not with the liquid additives, fortunately some pigments such as the graphite powder that I also use for bearings also makes a good black pigment and is sold as a pure powder. Silver and copper powders are also extra good and versatile. An example of a pigment I have had trouble with is titanium oxide, not because of the pigment but because of its liquid additive, having been only for fiberglass resin, would turn epoxy yellow with time. Yes you can with simple chemistry make your own pigments this is because of the reality of what paint really is, its just a glue filled with a pigment with most everything else just a mater of performance and what you want it for. I have tried making my own pigments and depending on what compounds you intend to make some will need to be used in much greater amounts. It seams to be a possibility that its possible to have some pigments also serve to add strength as is the case with adding milled Kevlar for one type of yellow, however note that its sunlight resistance is not great.
If you are concerned about the appearance of the parts you intent to mold, and for many castings this is reasonable, do as I do and use the epoxy's that are also used as a varnish and is clamed that one coat equals 50 of the ordinary varnish. This is sold as a 2-part mix and is very clear so that pigments will work well with it. Many commercial epoxies’ are slightly colored and as a result will require far more pigment and will still usually show a trace of the original color. I got my clear epoxy from Home Hardware, sold as a coating material. However I suspect its strength may not be as good? as resins designed for structural applications, I really don’t know.
Molding electronics panel’s, this is something I haven't yet tried and still hope too but felt I should mention it here any ways in case some of you do want to try this as a way to mold electronics panels. Its by using small rubber peace's with placements or raised surfaces for holes and cutouts for meters etc. in standardized sizes so they can be arranged, similar to the way printers type is for laying out a news paper, and then molded over with resin and or fiberglass. By the way I have used this method to mold ornamental concrete panel's with good looking results, both because I can forever change the mold designs as needed and because it can cost a lot less than what a single large mold will in some cases. I have looked into the idea of molding, into the mold patterns, small magnets or magnetic material to help with holding the pieces in place. But this probably would not be necessary if the mold pieces are reasonably thick, and you do not need to do vertical moldings, as may be the case with concrete moldings.
Don't forget to try working with pour able polyurethane's instead of just epoxy's to mold components as this material can range from rubber like to rigid plastic like and is very good in the silicone molds you can make and use. Its possible the silicone molds may last longer with this and it also has negligible shrinkage. Yes you can mold belts with this material by adding Kevlar fiber into it onto a mold also made of the belt. I have done this by making a mold somewhat like a loop by laying the belt on its side and sealing it around on the outside by using a soft jewelers wax but clay should work. Use a large loop of thin plastic or paper to save wasting silicone or do as I did and just put various sizes one inside each other and just make a mold of them all at once
I haven't had much chance to experiment with making fiber reinforced cable chain and you can see this sort of cable chain in some catalogs with some claims about its advantages such as being quieter and rust resistant. If you plan to try making these, it’s conceivable that you could use the sprockets themselves as a jig but I question how well. Its also reasonable to expect that you are likely to chose kevlar soaked in polyurethane resin, similar to what you would use to mold belts. As to be expected it’s hard to see when Kevlar is saturated with polyurethane, as both are so opaque. If you plan to do this, by wrapping your strands around short piece’s of composite rod. Remember not to just wrap it around them, as it will just become unstable, instead wrap it half way around and through a hole in the side of the shaft similar to what is used for cotter pins.
kevlar is better when it doesn't need to be pulled to be wrapped around jigs . A definite plus because then you have less tendency to pull the jigs out of precision
One of the ways I have used to cut down on the use of my RTV (room temperature vulcanizing) silicone mold making materials, is to coat the model with more than one layer, much like adding more than one layer of paint till it is reasonably thick. Then using your regular store bought silicone that is used for caulking, to glue sand or some other material, that a resin will bond to, then continue to finish with fiberglass cloth in epoxy to form a hard outer shell. However you should remember that the use of the regular silicone caulking compound can cause a shrinkage if applied in a thick layer, as I had had problems with this method when I tried to replace a lot of the RTV pourable silicone with it. In other words its not so good to do this for molds that can be poured all at one time and that require an at lest moderate thickness. Its more ridged when you have a hard shell attached, so do make sure if you model is not terribly complex, or so that your mold comes apart into lots of smaller pieces that can be bolted or clamped together.
I have also experimented with a similar method as a way to bond Portland cement to wood and to add new cement to old by using just the epoxy sometimes with fiberglass cloth as well. And then when still tacky or with a thixotropic thickener added apply dry sand to these surfaces that the cement will bond to. However the moisture resistance of epoxy is a great help to hold in the moisture so the newly applied cement won’t dry out. It also seams to cause destruction on one of my cement sculptures due in part because of the freeze thaw conditions of Canada and I expect because of the moisture resistance of the epoxy layer. Its interesting that the bond actually held and it was the cement itself that broke apart in layers
I have used casting resins to make electrical connectors and it should work well for making electrical adapters as well. Doing this I have found it important to seal up all small holes on the side that you intent to pour the resin, I usually make a thick putty mix with epoxy to carefully cover all these small openings. Also adding such things as micro spheres and milled fiberglass powder can really help to keep the resin from flowing into or out of any remaining small cracks or holes. In fact I usually wouldn’t dare, not include the fillers, and get good results and very little leaks when I use lots. The added strength, fire resistance or what have you, can be a bonus with fillers anywise. This is similar to why Portland cement will not flow through small holes and cracks because of all the gravel it contains. If you plan to use fiberglass resin, you may need to consider if your resin contains a wax, that wile it gives a tack free surface it also interferes with any additional layers ability to bond well. With fiberglass resins its often better to have a still tacky surface for the best bond with any extra-added resin. For other types of connectors you may need to consider the use of wax to coat or fill pieces, so you can later, if needed, remove the wax, perhaps by melting it off.
Mold releases, you will soon note that I often prefer to use a thin layer
of grease to hold on a sheet of aluminum foil as my preferred method largely
because it works so well on surfaces that are simple. I don't have to wait
for surfaces to dry as is the case with polyvinyl alcohol, or apply layers
of wax that and both are hard to see if they cover completely. Sometimes
it’s also an advantage to use aluminum foil as it can be used to
build up a surface so that when it is removed peaces are not so tight when
re assembled. And aluminum is usually easily removed, when it is difficult
you can use either sodium hydroxide or mild acid to remove it. I do recommend
you experiment with the other mold releases that are available so you will
become better able to decide what to use for what. Maybe remember to consider
trying internal mold releases that are added to resins to help in mold release
.I haven't tested these myself.
SOME NOTES FOR RECYCLING FOR PARTS
I found it interesting just how accurate your average aluminum door frame tubing is when I compared it with the accuracy of a bough ten aluminum yard stick, it was actually not as good as the door frame tubing. This is an interesting note for how using just junk can actually be suitable to do precision jobs, but its still wise to inspect all materials first .
All of the below information on using acids do find out more on how to safely use these before you do such as wear rubber gloves and always keeping a wash bottle filled with water near by as well as some baking soda for neutralizing the last traces.
If you want to separate regular steel from stainless, try using a 50% solution of nitric acid as this will eat all the regular steel and leave the stainless. Also a quick way to test for magnetic stainless rather than waiting for it to rust, as it is also undamaged by the nitric acid.
Try separating regular steel from brass or bronze by using a dilute sulfuric acid solution or copper salt but this will leave metallic copper powder
A neat way to shrink metal shafting is by using acids. Nitric plus 1 of water for regular steel and use a nitric plus 1 to 4 of hydrochloric acid mix for eating stainless. Hold your shafting vertically straight up or down into the acid mix till its diameter is decreased to what you need. I and people I show this to on eating a penny or similar item are usually quite surprised at how far you can go and still have it remain readable as an example of how evenly acids can do this.
Of course its neat for etching your name into metals by first coating with wax paint or tape and then scribe your name through this surface so the acid will only eat those areas.
You can experiment with the use of acid to sharpen files and blades by coating one side with a tape or wax that could be for example pushed into the backs of all the small teeth of a file. I first found out about this by chance when I had old files that were thick with grease and dirt that I had in acid to make ferrous sulfate. I also once used it to cut holes in hardened steel and noticed that when the acid got to the other side of the metal that was covered with tape it produced a remarkably sharp blade. Of course to use waxes you need to keep everything cool and some types of jewelers modeling clay like waxes would be best but glues, varnishes, etc. could be tried. A nitric plus hydrofluoric acid will even eat tungsten carbide but is especially toxic and will also eat glass.
Save those old floppy drives as they have some very nice short pieces of stainless shafting and a few small bearings that are useful
STUFF I WANTED TO TRY OR DO MORE TESTS ON
Please note that I am mentioning this without the slightest idea on how many experiments, or who has done work on this or if any such products are on the market
An interesting experiment I once did by accident was to make molten silver by igniting a mixture of sodium nitrate and silver cyanide. Makes me wonder if its possible to produce mixture that will produce molten bronze or other metal mixes this or a similar way. Thermites are good way to produce molten steel but uses iron oxide and aluminum powder in a mix. This will also work for nickel and other similar metals by substituting their oxides and producing alloys is simple by just mixing different metals. This mix produces a little over 2000 C but would be a lot hotter if the boiling point of aluminum oxide were more and of course under pressure it is. Try not to make anything explosive
I did some experiments substituting metal solder and metal fiber in place of fiberglass in resin with some results. I was interested because metal fiber could be bent into shapes and remain that way till sintered with a flux and solder, maybe zinc. Mostly I was interested in finding out what could be done with a metal like woods metal. Such as used in fire sprinklers or a similar alloy because these metals are about as hard as pewter, but melt at a remarkably low temperature, actually less than the boiling point of water. I wanted to experiment using these as solder for very fine metal fiber but I had trouble finding anything suitable and have only had courser heavier wire to experiment with. It would also be interesting what fibers could be coated with a film of metal that the solder will bond to. All of this could make a reusable reinforcement that could on heating be shaped into other shapes as needed.
Metal putty's by mixing a metal powder in solder similar to amalgams with mercury are something I wanted to experiment more with to see if it could be good for such things as fixing radiators or for body fill for cars because being putty it wont run off. You can make your metal powders for example by using iron to reduce a copper containing solution to give a fine copper powder.
I didn't have the chance to try making paste resistors by mixing different ratios of conductive powders into epoxy and then testing how well it could work, but expect some applications may give except able results for custom made circuit boards. I’ll let everyone know how well this works, when I get time to test it myself
WHERE TO BUY
I have gotten most of my fiberglass strand from a company that uses it to manufacture piping and usually this form can be the cheapest kind of fiberglass you can buy based on weight. At the time I bought mine it was about 1/2 the cost of the cheapest fiberglass cloth. I really had no source of Kevlar strands and had to obtain mine by unraveling a piece of Kevlar cloth .I expect it should be easier now to obtain it as single strands now and I have seen Edmund Scientific selling it in spools.
As is usually the case, the web is the best place to find suppliers but jut in case it might help I have included addresses I have found, used , or like along with a few random ones
These are probably all out of date.
SMALL GEARS ETC.
Low cost plastic gears etc.http://www.servolink.com
Boston Gear 14 Hayward Street Quincy, MA 02171 USA. E-mail boston.gear@industry.net ph(617)479-6238 web at http://www.industry.net/boston.gear , may no longer be around as I couldn't find them with this url .
W.M.Berg, Inc.NY USA http://www.wmberg.com ph (516) 596-1700 fax (516) 599-3274
RESINS , FIBERS ETC.
East Coast Model Center 17 Glen Stewart Drive Stratford , Prince Edward Island ,Canada C1A 8X9 order@ecnc.com 1-800-839-3262 B:\kevlar cord address.htm
. Aircraft Spruce and Specialty Co 225 Airport Circle, Corona, CA 91720 Phone (909) 372-9555 Fax (909) 372-0555 E-mail info@aircraft-spruce.com http://www.aircraftspruce.com They have or have had a really big catalog and sell all sorts of stuff for home built aircraft including resins, fabrics etc.
FiberGlast Developments Corporation, 95 Mosier Parkway, Brookvill Ohio, 45309 1-800-330-6368 http://www.fiberglast.com/ Of course as the name suggests they sell fiberglass, kevlar, resins, and they are where I first got some pour able polyurethane resins to mold rollers and belts etc.
Judge Enterprises 726 Gail Avenue Sunnyvale, CA 94086 Phone (408) 736-2067 Fax (408) 736-2095 E-mail 559519858@msn.com B:\Carbon fiber laminates.htm They sell a composite board with micro spheres core to use in model car making etc.
Shopman incorporated. 5101 Georgia Avenue. West Palm Beach, FL 33405 (561) 588-1258 shopmanfl@aol.com http://www.shopmaninc.comThe have marine industrial-composite materials as well as polyurethane resin, mold making compounds etc. To home hobbyists and professionals
A web site concerning composites
http://composite.about.com/industry/composite/index.htm
Silicones, Inc. 211 Woodbine Street. P.O. Box 363 High Point, NC 27261 Phone (910) 886-7122 This Company sells room temperature vulcanizing RTV mold making rubber compounds. This material is great for making molds for just about any resin or cement mix. They have various types that are best for different uses. Expect prices typically near 10.00 a qt or more, when in gallon quantities but you can buy smaller amounts
Mondo-tronics Inc. 524 San Anselmo Ave. 107-13 San Anselmo CA 94960 Order Toll Free 800-374-5764 Phone 414-455-9330 Fax 415-455-9333 E-mail info@mondo.com Web They sell memory alloy Muscle wires and related http://www.robotstore.com/
Atochem Sensors Inc. P.O. Box 799 Valley Forge, PA 19482-0799 for piezo film, hope they are still around. This is the film that will bend with an electric current is applied so you can make micro small fans, valves etc.
Measurement Specialties Inc. Tel (610) 650 1580 Fax (610) 650 1509 e-mail dhalvors@msiusa.com web site http://www.msiusa.com/sensors.htm On piezo film
Campbell Tools Company. 2100 Selma Rd. Springfield, Ohio 45505 ph(513) 322-8562 http://www.campbelltools.com This company is where I got all my precision brass tubing and miniature taps and dies etc.
Lapidary Journal 60 Chestnut Ave. Ste 201 Devon PA 19333-1312 (215) 293-0564 http://lapidaryjournal.com This is a magazine that supplies addresses for suppliers of jewelry making supplies including waxes, places to buy sell scrap gold etc.
My Address Dale Trynor, St. George N.B. E5C 3J8 , dalet@nbnet.nb.ca