The method is disclosed for producing relatively pure ammonium paratungstate from an impure tungsten solution. The method involves first adding hexamethylenetetramine to the tungsten solution and adjusting the pH to from about 1.0 to about 2.0 with a mineral acid to form a first precipitate of a tungsten hexamethylenetetramine product, which is then separated from its mother liquor. The precipitate is then slurried in water and the pH adjusted to from about 7.0 to about 8.5 with ammonia to dissolve the precipitate. The resulting solution is then adjusted to from about 1.0 to about 2.0 with a mineral acid to form a second precipitate of the tungsten hexamethylenetetramine product which is then separated from its mother liquor. The second precipitate is then slurried in a solution of water and sufficient ammonia to form ammonium paratungstate which crystallizes out on evaporation of the slurry. The ammonium paratungstate is then separated from its mother liquor.

Tungsten Powder Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-powder.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

Darts tuning is meant to determine a setup for your darts that fits your throw. When I am talking about setup I mean the flight/shaft system of the dart. This system is responsible for the aerodynamic behavior of your darts. It must meet the requirements of darts physics (see the technics section for a closer look at this). The main parameter for determining the correct flight/shaft system for you is the angle at which the dart sticks in the board. Unfortunately you can only see this angle when you are playing on a steel tip board. If you are playing only soft tip then you should switch to a steel board for darts tuning.

correct board angle

The correct angle is within 10 to 60 degrees. Just like in the picture above. The more consistent this angle is, the better. For instance, if every dart of your 3 dart series sticks in a different angle then something is wrong. Most likely does your dart wobble considerably, which can only be reduced by serious practicing. However, using a bigger flight shape will also help here as it adds stability.

Generally, bigger flights ("standard" shape or bigger) will give a greater angle, while smaller flights (such as "pear" shape) will give smaller angles. Note that when you are doing darts tuning always use the same shaft for comparison between flight shapes. Shaft length and shaft material have a strong effect on the flight/shaft system.

Also note that shaft weight (or even flight weight!) also have influence on this angle. The heavier the shaft or flight is, the smaller the angle will be. This is important when you decide whether you will use nylon or the heavier aluminum or titan shafts. The shaft rings can also influence this, as they make the shaft heavier.

Darts tuning needs work and patience. It should be done over a couple of days to eliminate possible daily variances in your throw. A good starting setup for darts tuning is middle length nylon shafts with "standard" size flights. From this initial setup you can continue working, depending on whether your angle is too big or too small.

Tungsten Alloy Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-alloy.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

Spinning means that your dart rotates (spins) when you throw it. Some players that have noticed this spin are concerned whether this is okay or a bad thing.

I don't think that spin is a bad thing. It is an additional source for errors, as it is an additional movement, but on the other hand spin also adds stability. In my point of view these two things eliminate each other, so there is no use worrying about it. In no case should you try to consciously make your darts spin or consciously try to eliminate spin.

Spinning has nothing to do with darts tuning. It is not determined or influenced by the flight/shaft system. It is determined by your personal throw.

Tungsten Alloy Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-alloy.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn

There are some options for outs with 2 darts left in hand. A dart thower need to respectiving single's  treble and take right way. The first region from 101 to 110 contains 4 numbers that can be shot out with 2 darts over the bull's eye. Here we go :( Trebles, doubles, singles: T20: treble 20D20: double 20 20: single 20 orT13: treble 13D13: double 1313: single 13and so on...)

2Dart Outs 110 - 101

T20 - D15 means: first dart treble 20 second dart double 15 (no third dart given: 2-dart out shot)

110 best option T20 - D2

107 best option T19 - D25

104 best option T18 - D25

101 best option T17 - D25

2Dart outs 100 - 71

Within this big range all numbers require a treble + a double. This table is pretty much like the usual "out charts" you might know, with the one exception that I give more variations when possible. For a better understanding of outs it will be very helpful if you compare these options with those options given for 3-dart outs. If there are differences, try to understand why!

100 best option T20 - D20

98     best option T20 - D19

97     best option T19 - D20

96     best option T20 - D18

95     best option T19 - D19

94     best option T18 - D20

93     best option T19 - D18

92     best option T20 - D16

.....

This is the "magic" number range. If you want to have a "guaranteed" dart at a double then you have to go for the single that leaves bull's eye.

Tungsten Alloy Manufacturer & Supplier: Chinatungsten Online - http://www.tungsten-alloy.com
Tel.: 86 592 5129696; Fax: 86 592 5129797
Email: sales@chinatungsten.com
Tungsten & Molybdenum Information Bank: http://i.chinatungsten.com
Tungsten News & Tungsten Prices, 3G Version: http://3g.chinatungsten.com
Molybdenum News & Molybdenum Price: http://news.molybdenum.com.cn