Monday, January 16, 2017

Basic Pivot for Whirligig or Weathervane

Basic Pivot for Whirligig or Weathervane

    In this post I wanted to go into more detail about the whirligig or weathervane pivot and how it is put together. The diagram below is intended as a basic guide and can be adjusted in size or scale according to the size whirligig or weathervane that you're creating. 

    For basic demonstration purposes this is a basic 12 inch pivot for whirligig or weathervane. Were using a heavy screw with threads that only go halfway up and a non-tapered shaft. The type of screw head does not matter as it will be cut off once the screw is installed in the vertical mounting board. Screw the screw into the vertical mounting board just enough to cover the threats. Making sure to keep shaft of screw vertical. It may be necessary to drill a pilot hole to help keep the screw straight, as this is what your project is going to pivot on. This should leave the upper half of the screw without threats exposed. Then using a Dremel tool (with appropriate safety goggles and other protective equipment) use a cutoff blade to cut off the screw head and a grinding bit to either round the top of the screw shaft or grind a concave dimple. Once you've completed your vertical board with pivot it is time to create the horizontal part of your pivot. 
    One of the important things to take in consideration before drilling a hole is the metal or plastic sleeve that will fit inside the hole. The metal or plastic sleeve should fit tightly in the hole but the screw should fit closely but not so tight as to inhibit the upper part of the pivot from rotating. Any wobbling in the rotation of the upper pivot will simply create excessive wear and erratic movements.
    At the bottom of the hole place a 1/4" hunting shot (slingshot ammo found in the sporting good section) or a small ball bearing, or BB depending on the size hole being used for the vertical shaft. The basic reason for placing the metal ball at the bottom of the hole is to prevent metal rubbing against wood and to reduce friction as the upper pivot rotates. Using a metal ball that is slightly larger than the metal or plastic sleeve and then placing the metal sleeve on top of the metal ball in the hole will help keep the metal ball in place.
     Using wood stock that is approximately 1/2" X 1/2" X 12" long measure 3 inches from one end and drill a hole.  Where you position the whole will depend on how you want the pivot to react to the wind. The closer you position the hole to the center, the more erratic the pivot will act. The closer to the end you position the whole the greater the force that will be applied not only to the pivot reacting to the wind, but also to the pivot itself. I have found that a quarter of the total distance gives a good balance to the pivot and does not put excessive strain on the pivot. 
    Once you have the metal ball and sleeve in place the two parts to the pivot should be ready to go together. You can put a small amount of graphite lubricant at the bottom of the hole before you put the two together. 

There you have it a basic pivot to mount your whirligig or weathervane on. For this and other ideas please be sure and check out our website www.nevadacrafter.com and our blog's at http://craft44.blogspot.com/ and http://nevadacrafter.blogspot.com/ and http://3dpenideas.blogspot.com/
    If you have any questions please be sure and post those questions to the blog and I will try to answer them as promptly as I can.

Friday, January 13, 2017

Spacewalking astronaut and space capsule weathervane

Spacewalking astronaut and space capsule weathervane


   So the idea or concept was to create an astronaut walking in space. At first the design seemed to be simple, but as I researched it more I quickly realized that I could take the design to whatever level of detail that I wanted. For presentation purposes I have chosen a simpler design than what an actual astronaut and space capsule would look like. It may be possible to create lifelike replicas but as this project would be exposed to the elements I chose to keep it simple. This way if the weathervane should become damaged it would be easy to make repairs. 
    I chose a weathervane design to minimize moving parts but also decided to add what is referred to as a wobble effect. This is done by adding a part of the design to a spring, metal band, or spring wire. In this case I'm using spring steel wire as the astronauts tether. The bouncing around motion that the astronaut will give in the wind will add to the illusion of someone actually walking in space. 
    The space capsule is actually cut out of 1/2" wood stock and the lower flame is notched so as to fit over the side part of the pivot. The thicker Woodstock allows you to make a more secure attachment to the pivot and the overlapping flame at the bottom will give it a more three-dimensional appearance. It should also be noted that I have intentionally left off the country of origin insignia on the side of the space capsule. This is so that you can put your own insignia on the side of the space capsule such as an American flag or some other countries insignia. 
    The pivot itself is a basic design and you can refer to the pivot design at the bottom of the following post. windmillhorses-weathervane-whirligig 


For this and other great ideas be sure and check out our website www.nevadacrafter.com
and some of our other blogs such as
http://craft44.blogspot.com/
and
http://nevadacrafter.blogspot.com/


Tuesday, January 3, 2017

Lubricating whirligigs and other mechanical projects

Lubricating a whirligig or mechanical project with moving parts.

    Lubricating whirligigs or mechanical projects can be a challenge. The materials you work with can vary from metal to wood and even plastic. Add to this a project that is exposed to the outdoor elements, wind, rain, dust, dirt and even the unexpected squirrel.
    The basic challenge is to keep moving parts moving and there are a few basic rules that you need to consider when you're creating mechanical art.
    The first rule of thumb that I was taught long ago, is to always try and work with like materials. Putting a moving metal part against a wooden part will always result in the wooden part eventually being worn away. Putting plastic or nylon parts in between will help lengthen the life span of your mechanical wonder, but will have to be periodically replaced. And always try to keep lubricated parts sealed when possible. Always use washers and spacers when possible to keep metal parts from rubbing against wooden parts. 
    As for the lubricants themselves, my go to lubricant has always been a pencil. The graphite used to make the pencil lead makes a perfect lubricant. Rubbing a pencil lead on a propeller shaft works wonders and is resistant to most weather conditions. Liquid graphite can also be used when you have metal to metal surfaces, such as brass tubing and brass welding rods used for propeller shafts or other metal to metal parts. 
    As you're creating these projects you should always keep in mind to create projects that can be disassembled. This will make it easy for the owner not only to periodically lubricate moving parts but also make any repairs or replace any worn parts that need replacing. Another option is to also include in your projects lubricating holes, as shown in the diagram above. These are holes or tubing that allow you to lubricate the moving part without disassembling and are usually mounted on the bottom side prevent collecting dust or water. 
    White lithium grease is also an optional lubricant. Normally used on bike chains and other outdoor moving parts such as door hinges. It also is extremely weather resistant and has the added advantage of being in a spray form. 
    The next lubricant is actually a solid and usually in the form of nylon washers. But as I have found over the years nylon washers and metal bearings can be very expensive to use. Using crazy straws and washers cut from milk jugs will work but keep in mind most plastics are designed to be biodegradable and may not last very long if exposed to sunlight. Crazy straws dipped in a pot of boiling water will immediately straighten and as long as they are cut to length and hidden inside the whirligig or project they will last quite a long time. Add some graphite lubricant and they will undoubtedly outperform most expectations. Also keep in mind when using plastic or even brass tubing you will want to keep the sizes close fitting. A loose moving part will wear much faster.
   
    I hope these tips on lubricating your mechanical art are of help. Please be sure and visit our website www.nevadacrafter.com for more tips and ideas on your next craft project.