DoctorDraco asked:

This was the 2nd place plane at the 2008 KY state science olympiad competition. This flight was about 1:41 and managed to pull 2nd place. Our top tier (my) plane, managed to get first with 2:05:73, but I did not film it because we thought we had screwed it up (our first flight was like 20 seconds). :\ It also should have been around 2:30 (stupid 26 ft gym ceiling!), but during its descent, it managed to fly under an air vent that was turned on, and it was pushed down about 7-10 ft. Overall, our 3 teams got 1st, 2nd, and 4th. The team that scored fourth did something dumb again. dupont Manual 2008 KY State Competition Electric Vehicle: youtube.com dupont Manual 2008 KY State Competition Robot Ramble 1: youtube.com dupont Manual 2008 KY State Competition Robot Ramble 2: youtube.com

Josh Elkins asked:




When starting out in the world of rc planes one of the decisions you need to make is what kind of plane to get. Besides what model of plane is going to be the best for a beginner we need to look at whether that model should be gas or electric powered.

For me there is no question that a beginner rc pilot should start out with an electric plane and here is why:

1. Price. Electric planes are far cheaper than gas planes. Just the motor for a gas plane can cost more than an electric plane. Then you still need the transmitter, servos, batteries, etc.

2. What’s in the box. Most beginner electric planes come with everything you need to get started flying. Plane, transmitter and batteries. Nearly all gas planes are in kit form. You have to build the plane and purchase all the parts separately. This is why they are so much more expensive.

3. You don’t have to build it. Most electric planes are made from Styrofoam or plastic and come fully assembled or need almost no assembly. You can be ready to fly just about as soon as the battery is done charging. Gas planes are almost made up exclusively of wood and need full assembly.

4. Ease of use. An electric motor is far easier to use than a gas one. You turn on the power and that’s it. Gas powered motors require you to add the fuel and tune the motor before you can fly. It’s a lot more work.

5. Emotional involvement. Why do I say that you might ask? We get more emotionally involved with something we have made ourselves versus something we purchased already made. Believe it or not many beginner pilots who have started with a plane they assembled themselves are reluctant to fly it. As a beginner pilot you are going to crash your first plane and no one wants to destroy something they have spent so much time building.

Electric planes are the way to go for a beginner rc pilot. Price, ease of use, and what you get in the box make it much easier and cheaper for a beginner to get started in the world of rc planes. Good luck and happy flying.

?Angie? asked:


What’s the best wing design for a balsa wood plane? Anyone? What other variables would help a plane fly?

pandaman434 asked:

Balsa wood plane that my aunt gave me + my sis so we built it and started to fly it =]

Paul Grossman asked:




Drive across any city in the U.S. and you will see a broad range of ideas on what constitutes a picket fence. This is true because so many people are given information on the fly about building fences. The result is usually the same – a sagging, snaking, tonguing or leaning fence. With the cost of the average fence at about $22.00 per foot this is a sad result that no homeowner should have to live with.

One of the first design flaws in fence building is to believe that the vertical supports ( usually 4x4x8 treated pine ) can be set on eight-foot centers. This never works, unless cross braced, which adds additional cost to the design. The load is too great for the span and the fence eventually sags.  Always set your fence on six-foot centers with at least 2.5 feet of concrete at each vertical. We will assume your fence is on level ground, since hilly ground usually requires a professional.

Now, let’s line out the material we will need to build a 30 foot fence, as an example. The entire frame of our fence will be cut from 2x4x12 treated pine ( TP ). We will allow four six-foot lengths (which will be explained later) between each vertical so we will need to buy two 2x4x12’s for each space between our verticals. If your fence is running 30 feet, you will need 30/6 = 5 spaces x 2 = 10 ( 2x4x12 ) TP for the frame and six 4x4x8 TP for the verticals. Your count is one more vertical than the spaces between verticals. Always sketch your construction design before getting material. A picture is definitely worth a thousand words.

A good estimate for your cement is one 80 lb sack of ready mix or sacrete for every two verticals. However, it is better to under cut this amount so that you don’t lug those 80 lb bags back to the lumberyard. You can always figure what you need easier than you can return what you don’t need and storing cement is never a good idea. Below is the procedure for building a fence that should last 30 plus years. Every piece of wood should be TP – treated pine. 

1. Your initial fence vertical layout center should be about six inches off of your property line. This allows 1.75 inches of 4×4 backdrop plus .75 inches of your picket width backdrop toward the property line. This gives you 3.5 inches left away from the property line. Always check your local ordinances to find the minimum distance from the property line and if you need a permit. Also, make sure you call your local utilities to mark any lines that might be in your digging path. I have found it is better to talk with your neighbor and discuss your fence beforehand so they can give their feedback before you invest so much money and time.

2. Layout your fence using a strong nylon twine that can handle a sturdy pull. The layout is done by using stakes that you can purchase pre-made or make yourself from 2×2 pine. Just cut an angle end on a two-foot stake and drive it down using a small sledgehammer. You will need enough stakes to run the length of your fence with one at every 30 feet. The twine will be stretched between stakes and used to mark the vertical 4×4 edges, while maintaining a straight fence. Once the twine is secured, go to an end and line sight your twine making sure it is straight. Your eyes are accurate to 1/32 of an inch longwise and about 1/8 of an inch front wise. 

3. Your vertical 4×4’s will flush right to the edge of the twine without touching it. Given the width of a 4×4, the twine acts as a way of keeping each vertical perfectly flush with each other. Remember, flush means that if you where to look down a line of verticals, they would all become one at the same time. That is, they are all in the same plane. Plumb means vertically level with gravity – requires two directions of leveling and level means horizontally level with gravity. So, our fence must be plumb, level and flush to look right, like most things in construction.

4. We have staked out our fence line with twine, checked property distance to the line and got an okay from utilities to start digging. Measure 2.5 feet from the bottom of your posthole digger up and mark a good visible line on the digger to indicate the depth of your holes. Remember, your twine is running across the centers of your holes. Cut several pieces of twine to tie to your stretched line at six-foot intervals thus marking your hole centers or use a black marker. Tip: It is easier to lay your 2x4x12’s end to end directly under your twine, place your measuring tape at one end and layout where your hole centers will be on the wood. Now, walk the line and tie your pieces of twine to the stretched twine directly above each layout. Once you have your string pieces tied to the line remove the wood to dig your holes.

5. Place your digger directly over the marked line at center and drop your posthole digger with a little force to mark the ground where the hole is to be set. Make sure the digger is turned in such a way as to not cut the twine. Remember, we are flushing the verticals to the center of the holes so the hole should be large enough to backset the vertical by 1.75 inches. A good rule is to dig more hole toward you so there will be enough hole to move the vertical. Use a single stake to keep the line away from the hole while digging. Start your dig slowly scribing the hole as exactly as possible. Remember, the posthole digger is being directed by gravity, so let it drop straight down while you add your speed to it. Dig all your holes and drop a vertical into each hole – they will lean against the holes. Check each vertical for flushing to the line and plumb (vertically level in two directions), making sure you have enough hole to move your post if needed. Re – measure the distance between each hole with a single 2x4x12 by laying it inside the hole edges and make sure each hole is in the right position. It is also a good idea to walk to one end and view the holes longwise to see if everything looks straight.

6. Now, we set the verticals. You do have a wheel barrel, right? You will need a medium sized barrel. One that can hold about four 80lb bags of cement mix. You won’t be putting 4 bags in the barrel at a time, but with the water you will need about the same volume. Wet the bottom of the barrel with about 2 inches of water and put one bag of ready mix concrete mix in the barrel. Wet the entire bag with water and take your hoe and split the bag while spraying a small amount of water on the bag. This keeps the concrete dust to a minimum. Dump the bag slowly into the barrel and turn it over to remove the remaining paper. The hoe is a very necessary tool that you will use to rake the concrete while applying the water. Work the cement with the hoe making sure to get the bottom and edges of the barrel, while spraying your water. The consistency of the mix should be wet enough to pour but dry enough to shovel. Use a pointed shovel and dump one shovel at a time of mix into the hole while shaking the vertical. This makes the cement flow evenly around the vertical and level with the hole. A very necessary tool to have, when needed, is a long pry bar ( about 25lbs ) that you can insert between the vertical and the hole, at the bottom of the hole, to flush the vertical to the twine. Ideally, the vertical should be plumb ( vertically level in two directions – level from the south and level from the west – opposing 90 degree angles ). Don’t get confused with plumbing vs leveling. A plumbed object points toward the center of the earth and a leveled object is 90 degrees away from plumb or plumb is straight up and down and level is straight across plumb. Your verticals will be set right when they are about 1/8 of an inch from the twine, parallel to the twine ( flush ) and plumb. Put enough cement to fill the hole and surround the vertical slightly piled up. Smooth the cement with the back of the shovel around the vertical. If your verticals are set right, they should all become one when viewed longwise. Let the cement setup for about three days or so.

7. Framing your fence requires building load and wind sheer support. Load is the weight of the fence straight down and wind sheer is the force exerted by wind directly against the fence. It stands to reason the load will always be the same but wind sheer depends on where you live. If your fence is set in a windy environment, then wind sheer plays a big factor in shaping the fence. Inadequate wind sheer support causes a snaking effect when looking longwise down the fence. Seen a lot of snaked fences in my time and so have you. Another adverse factor confronting your fence is, what I call, cupping. Have you ever seen a fence picket that looks like a spoon, that is, the picket bows vertically and takes on a spoon look. This is caused from improper nailing or picket fastening. Well, Mother Nature will cup any wood just from repeated wetting and drying overtime. So, regardless of low or high wind sheer, it is better to supply cross frame support for your fence to prevent the snaking effect of wind or rain.

8. There are two methods of laying out pickets that I have used in fences – string leveling at the top and 1×4 leveling at the bottom. The string method is best when the ground is level since it guarantees each picket is at the same height. The 1×4 is better used on un-level ground since you can stair step the pickets off of each 1×4 regardless of the terrain. So, we will use the string method for our fence.

 

9. You should have about 5.5 feet of 4×4 above ground to work with. We are assuming your ground is level ( which is seldom the case ), so the cuts made on each vertical will be level. Start at one end of your fence and set a picket against the vertical to get the height of 4×4 cut. The picket is 6 feet long, but it is better to use an actual picket than measuring. The picket should be only 6 inches above the horizontal top 2x4x12 and about 1 inch off of the ground, so use the picket to find where the 4×4 vertical must be cut to ensure, along with the top 2×4, that it is 6 inches higher. Refer to picture 1 for a look at the frame side of the fence. Once you have the height you want, mark an arrow pointing to it. We will pull off of this mark to level all of the verticals. Drive a six-penny nail on the mark to hold enough twine tension for about 30 feet with 20 lbs of pull. Set your twine on the nail and run about 30 feet of twine level against the verticals. You can purchase line levels for very little. Get four or so, to show levels down the length of the line. Note: It is always a good idea to view any line longwise from one end to ensure no sags. Once your twine is level, mark each vertical where the twine crosses it. This will be the cut to make all verticals the same height. Now, remove the twine and using a tri-square, make square marks ( 90 degree off vertical ) in two opposing directions on each vertical where your marks were made. You can skill saw the square marks to cut the verticals or chain saw them. Using the skill is better since you must get a flat surface on the top of the vertical. It takes some practice, but turn your skill perpendicular to the vertical, cut one square mark at full saw depth and then cut the other square mark at full saw depth. This will leave a small amount of 4×4 that you can hand saw out to remove the excess 4×4 top. Make sure you get a flat, level cut since your top rail ( 2x4x12 ) will be placed face down on the vertical tops. Finish all of the verticals and view them longwise to see if they are flush, that is, they disappear from view at the same time.

10. If everything is right, each vertical will support your top rail plumb, level and flush. Place your 2x4x12 on top of the verticals, face down, and make necessary cuts to overlap the top rail at the center of the verticals. If you have a perfect layout, you should not need to cut any of the top rails, but this is not usually the case. Once the top rails are set on the verticals end to end, fasten them down with 3.5 inch deck screws or 16 penny galvanized nails. The deck screws are more expensive but will not move out with age whereas the nails will. The only nails I use in fencing are those holding the pickets against the fence. If you use deck screws, make sure they are the inset hex head type since you will need a lot of torque to drive them down. Depending on which side your pickets will go, flush the top rail on the picket side to get good surface for the pickets. The top rail is part of the wind sheer support for the fence to keep it from snaking. The pickets will ride just six inches above the top rail, thus preventing what I call ‘tongue effect’. ‘Tongue effect’ is when you can look down a fence longwise and see one picket top headed north and another headed south, caused by allowing too much picket above the top rail.

11. Now may be the time to ask yourself which side of the fence to put the pickets on. It is never a good idea or look to reverse a fence, unless it is against another fence or impossible to picket. It has become somewhat popular, in the last 20 years, to reverse fence sheathing, showing the frame side to the public. This not only depreciates the value of your property, but it gives ready access to anyone to climb over the fence with little effort. Remember, the purpose of the fence is to provide not only privacy but security as well. Another reason to keep the frame side on the property side is that it allows the owner access to the frame to handle repairs and load problems in the future. From the point of decor, your property has much better curb appeal and the frame rails running on the inside allow you to use them for potting plants, party cup holders or just about anything you need.

12. Getting back to the frame, we have the top rail finished, so the next important rail is the load-bearing rail just under the top rail. This rail runs edgewise underneath and against the top rail. Its purpose is to provide load-bearing support to the pickets, keeping the top rail from bowing with gravity. Measure between each pair of verticals and cut a 2x4x12 to fit snug against the verticals edgewise. You should get two rails per each 2x4x12. We will use the excess from the 2x4x12 cuts as jackleg supports. The complete top rail including the load support will look like an I – beam with the exception that the load support is set flush with the picket side of the fence. This gives added wind shear and nailing support to the fence. Toenail 3 deck screws at each end of the load supports, making sure you countersink the heads on the fence side. This allows the pickets to flow against the rail smoothly. Once the load rails are secure, drive screws through the top rail and into the load support rail drawing them together as one. Use the remaining left over cuts, from the top rails, as jacklegs that will go under the top rail load supports. Again, secure your jacklegs underneath each end of the load rails with three deck screws at cross patterns. The complete top rail is virtually impossible to overload since it is actually a truss. It also is a sheer support from cross winds and drying that would eventually turn your fence into a snake.

13. The next important rail is the middle load bearer. This rail runs exactly like the top load bearer between every two verticals. It runs flush with the picket side of the fence to support the pickets. This rail not only adds load support, but great nailing surface and some sheer support as well. Use your jacklegs at each end of the middle rail with the same deck ***** pattern.

14. The final rail support is the bottom sheer support rail. This rail runs between verticals turned face down just like the top rail. Run the bottom rail about six inches off the ground level. It is supported by jacklegs and toe nailed deck screws. Remember to flush to the picket side of the fence, which is the same for all rails.

That is the complete frame for our picket fence. The next job will be sheathing the frame with our pickets.

15. We will use the string method to picket our fence. Your picket will be fastened at one end of the fence about 3/4 inch above the ground, with 1.5 inch galvanized wood screws. Use only two, one at the top and one at the bottom. You may need to adjust your picket and the screws are easy to remove. Before you fasten the picket, plumb it with your level placed on one side of the picket, lengthwise. As you fasten pickets to the frame you will need to occasionally check plumb to ensure your course is running correctly. Like most wood, pickets are at times cut irregularly, which forces the builder to make necessary adjustments. Adjustments to correct pickets are done gradually. That is, if you check plumb and find out that your last picket needs to move left at the top to correct the run, then you move the bottom of the next picket slightly right. Continue to do this until the course of pickets return to plumb. This is why you should always check your plumb about ever 4 or 5 pickets.

16. Drive a six-penny nail straight down through the top of your fastened picket, leaving enough nail exposed to tie your twine to. Tie the twine to the nail and drive the nail down until the twine touches the top of the picket. The twine will be your top guide while laying out the pickets. Unravel enough twine to run about 30 feet of pickets and fasten another picket to the fence, the same as the first. Make sure it is plumb and set about 3/4 inch above the ground. Drive another top nail into this picket, leaving enough nail exposed to tie the twine to. Loop the twine around the nail twice and with your left hand ( if you are laying out left to right ) pull the twine while pulling the loop with your right hand. The twine should be taunt enough to be straight when view longwise. Usually about 20 lbs of pull does the job. Place your line levels at different locations along the twine to check level.  Adjust the line to the proper level and tie it off on the exposed nail.  Since we are using top line to level our fence, don’t worry about the ground below the fence if it drops at different points.  You will just need to add more dirt to low areas after your fence is finished.  If the ground is too high at areas you will need to shovel the dirt away to allow the bottom run.  If it is a dramatic change in ground level then reset both pickets until you get what you like.  Sometimes you just have to split the difference between digging or resetting the pickets.  Visualize what your completed fence will look like and then make your decision.

17. It saves a lot of work to have a nail gun when hanging your pickets; however, whether by hand or by nail gun, you will work from your starter picket to the finish, placing three nails through the pickets at the top, middle and bottom rails. If you are using treated wood for your pickets, they must be set tight against one another to ensure a privacy fence. Treated pickets will shrink over 2 years some 15 to 20 percent. This will increase your fence gap dramatically. So, unless you are using completely cured TP pickets, you must set them tight against one another – no gap. I have seen homeowners gap TP pickets about a quarter inch, only to have a 2-inch gap result in 2 to 3 years! Hardly a privacy fence!  Set each picket about 1/16th of an inch below the top line, making sure to never touch the line since this will change your level.

18. After setting your pickets, it is a good design to run a 1×4 footer directly over the bottom of the fence, placing a single ***** through the footer into each picket. This accomplishes two things. It draws the bottom of the fence into a nice tight single plane and it also protects the bottom the fence from weed eater wear. You can use this banding technique anywhere you wish on the fence to straighten tongue effect or draw pickets into a single plane, using a 1×2. Just be careful to use the proper length *****. You should never have exposed ***** ends on the other side of the fence. This becomes an accident waiting to happen. Check the opposite side of the fence for any exposed nails or screws.

19. That’s it for your fence. Except for capping off the last vertical with trim. A single picket can be used to trim the last vertical, if needed. Don’t forget to treat your fence with a good water sealer after it dries. This is usually about 2 to 3 months after install.  Finally, if you used completely dry TP pickets, treat the fence before it rains since they will swell with moisture.  To see pictures of our fence, please visit http://alphalane.com.

Norman Stanley asked:




A common problem for golfers is the correct use of the fairway wood. Many amateur players try to lift the ball into the air rather than let the loft of the club do it.

Tip one; let the club do it’s job. Engineers and very clever people design these clubs to perform a set of particular actions, getting the golf ball airborne is one of them.

Fairway woods are incredibly useful clubs performing a variety of tasks from the obvious like hitting the ball from the fairway to driving off the tee, from getting you out of the cabbage to chipping from the edge of the green.

Learn to swing your fairway wood and you will have a useful ally in your golf game.

For this article we shall concentrate on the most common aspect of the fairway wood and that is the second shot from the fairway into, and hopefully onto, the green.

Visualise this; the club will sweep the ball from the turf without taking a divot. A slight bruising of the grass is all that you want, the club face will connect with the ball at the bottom of its arc, the lofted face will cause the ball to rise into the air and fly down the fairway.

Set up to the ball in the manner of your driver with a stance slightly wider than your shoulders, this gives you a firm basis for your swing. Your spine will will be tilted slightly to the right to accomodate the fact that your right hand is lower down on the club.

The ball is played from just inside your left heel and so your sternum or breastbone will be behind the ball by a couple of inches.You can check this initial positioning in a mirror at home so it becomes natural on the course.

To begin the swing take the club back close to the ground. Practice the move by placing another ball a few inches behind your target ball and pushing it away with your club head. The swing arc is wide and fairly shallow and tempo is all important. Start practising at half speed to achieve the right technique.

The down swing will return low and wide, the club head will brush the grass and be fully at the bottom of its arc when it impacts the ball. Remember, no divots. If you are taking a divot it means the club is striking the ball on the downward direction, this will cause it to pop up violently losing forward momentum or you will scud it into the ground. Neither of which is desirable.

Develop a sense of hitting the ball down the fairway, not up into the air. After impact allow your arms to extend through the shot along the target line. This should help keep the club square at impact meaning a straighter, more accurate shot.

As mentioned earlier in the article tempo or timing is crucial to consistency with the fairway wood so practice sweeping the grass without the pressure of hitting a ball and even hum a little tune which helps you swing rythmically. It can become the most natural of movements. Good luck and good golf to you.