大卡司总部地址:制作10英尺的风力发电机组（5）

Once the resin seems hard then remove the C clamps and the nut in the center. Use a chisel or a screw driver to gently pry around the lid untill it breaks loose.

Once the lid comes off you can usually turn the mold upside down and the stator will just fall out. If not then turn the mold upside down and tap on it with a hammer or pry gently at the edge of the stator. It should come out easily.

Use a file or a sander (or both) to clean up the edges of the stator. The inside diameter must be pretty clean because there's not a lot of extra room between this hole and the wheel hub which will exist inside it.

It's nice if you do drill the 3 holes for the studs that hold the stator to the wind turbine before you do the welding on the frame, then you can clamp the stator bracket to the stator on center and drill 1/2" holes right through it. If you do it this way, it's very important that the center hole of the stator be just about perfectly centered with the stator bracket. Also be sure to have the 3 holes come out between coils - preferably with the 3 wires coming out between the same two holes. You don't want to hit copper with the drill bit!
If you've allready welded up the frame then you can center the stator on the wind turbine frame against the stator bracket and clamp it there - and drill through the holes.

The magnets are so strong they can be tricky to seperate off the stack. The best way is to place the stack on a wooden workbench and hold the stack firmly. Then grasp one magnet firmly with the other hand and slide it off. (you'll not be able to just pull them apart, you have to 'shear' them apart)

Now we can place the first magnet on the bottom magnet rotor. The template is pinned to it and made of wood or Aluminum so it won't move. But the magnet is strongly attracted to the steel disk so we need to hold that down with one hand. While firmly gripping the magnet in the other hand, bring it towards the edge of the rotor and 'slide' it into the slot. (don't just try to put it down on - it will pull out of your hand and hit the rotor hard - possibly breaking the magnet!)

The magnets need to be spaced around the disk with alternating poles facing up. All magnets have two poles, a North and a South. Opposite poles (North and South) attract one another, like poles repel. It doesn't matter how we put the first magnet down so long as things alternate from there. The safe way to place the rest of the magnets is as follows: Hold the magnet rotor down firmly to the work bench with one hand which should be placed over the magnet that's next to the one you're about to place. Then, holding the next magnet firmly, bring it over your hand which is holding down the rotor. If the bottom of the magnet in your hand is repelling the one on the rotor, then slide it into the slot carefully in it's current position. (Because we know that if the bottom of the one in your hand is repelling the top of the one on the rotor then we have like poles facing each other, so the one in your hand has the opposite pole facing up as the one on the magnet rotor)

Once all the magnets are placed on the first rotor you can remove the pins and pry the template off. Do this carefully so the magnets don't slide around.
回复 引用TOP
hog

论坛元老

48#
 发表于 2010-8-30 13:22 | 只看该作者

Run a bead of thin viscosity cyanocrylate glue (Super Glue) down both sides of each magnet. Large bottles (2oz usually) are available at most hobby stores. It's also handy to have 'accelerator' which will force the glue to harden immediately. The accelerator usually comes in a small spray bottle. We don't rely on this glue to hold the magnets down forever, it's a temporary means to keep things in place till we finish the casting. If cyanocrylate glue is not available then other glues should also work fine. Epoxy would probably be fine it just takes longer to dry.

I expect you could skip this part all together, but I believe it offers some insurance that our magnets will never fly out. Also - if the resin cracks this will keep things together for us. Take a roll of fiberglass drywall tape (this stuff is sticky on one side) and cut the roll with a razor knife so that you can peel off a strip of the tape about 1/2" wide.

Wrap the tape around the magnets several times. Be sure that none of the tape sticks up above the top of the magnets.

Now that the first magnet rotor is finished, drive a nail somewhere in a wall in a high/safe place and hang it there. It's a somewhat dangerous thing and should be kept in a safe place.
回复 引用TOP
hog

论坛元老

49#
 发表于 2010-8-30 13:22 | 只看该作者

Now to begin the second magnet rotor. Put the template on it so that the 4 holes line up and one of the slots lines up with the marks we made earlier. This assures us that the magnets we place will be facing each other when the rotors are assembled. The top of the first magnet on this rotor must be the opposite pole as the top of the first magnet we placed on the first rotor. In other words, the two surfaces facing one another must attract one another. Once you get the first magnet down, follow the same proceedure as you did with the first magnet rotor.

Check your work!
You can easily double check your work now. Find a small magnet and hold it in your hand (dont turn it over - hold it in the same position always for the testing). Each magnet rotor has one magnet (the 1st one we placed) between the marks we made. The test magnet should attract this magnet on one magnet rotor, and repel it on the other. Then we can go around each magnet rotor and the test magnet should attract one magnet, repel the next one, attract the next one etc. If you made a mistake, you need to knock loose the offending magnets, put the template back on and get them right. Once all the magnets are placed and the tape is wrapped around them it's a good idea to clean the magnets and the rotors one more time with laquer thinner to make sure there's no grease. This will help the resin stick to the magnets.

Cut out two rings from fiberglass mat, or fabric. They should be 12" in diameter, with a 6.5" diameter hole in the center.

Grease the mold everywhere (Except on the bottom - that's not necessary). A good mold release is car wax, or Johns** wood wax. We've also used shortening from the kitchen and axel grease (axel grease is kind of gross and messy but it works). Grease it really well especially the first time you use the mold. The first coat tends to soak into the wood but after several applicati** it gets better. The point here is to make the mold greasy so the resin won't stick to it. Once all the parts are greased well then run a bead of caulk around the outside of the 12.5" hole in the mold. Also run a thin bead around the outside of the 1/2" thick 6.5" diameter disk. If it's not still there, stick the 1/4" drill bit in the center hole, we'll need this for alignment.
回复 引用TOP
hog

论坛元老

50#
 发表于 2010-8-30 13:22 | 只看该作者

Drop one of the magnet rotors into the mold carefully. It fit nicely on the smaller 2.75" disk in the center of the mold so that the magnet rotor is a good fit and about pefectly centered.

Put the 6.5" diameter disk down. The drill bit will serve to center it on the disk. The side that we've run caulk around should face down and we need to press it down onto the magnet rotor. The caulk will assure that no resin can run under it.

We use polyester resin to cast the rotors. We get this stuff from almost any autoparts store. It's best to buy it by the gallon (it takes about exactly one gallon to build this whole machine). It comes with hardener in small plastic tubes.