Tip 1: How to thread

When repairing furniture and various household goods, in the course of the work, often need to connect parts of structures by means of threaded connections.Tapping the thread quality in the home, labor-intensive and requires the skills of occupation, but this problem is solved.
you need
  • To work needed: a vise, file, taps, dies, wrenches, lube and desire.
thread - is, in essence, a spiral groove is cut into the outer or inner cylindrical surface.It is used primarily for connecting various parts to each other.In engineering can be used to convert a translational motion to rotary motion and vice versa.There are two types of thread such as metric, with an angle of 60 ° Profile and pipe with an angle of 55 °.
in Metric thread diameter and thread pitch measurements in millimeters.In designating metric thread used alphanumeric marking, for example M8h1,5.The figure of eight corresponds to the diameter of the thread, and the thread pitch is 1.5, the distance between the coils.In
inch thread, measurements are in inches and the number of threads per inch.One inch equals 2.54 cm. For example, write down 1 inch thread 1/4 ".
Thread cutting.
to cut external threads need to take the correct size plate and prepare the workpiece, and in particular,workpiece pick a certain diameter. The diameter of the workpiece for threading determined by the table. In practice, for cutting, such as thread diameter M6 needs rod section 5.92 mm, that is about one-tenth of a millimeter smaller thread M8, harvesting must have a diameter of 79 mm.
Here's an example excerpt from the table diameters of cores for metric threads:

thread diameter / stem diameter (mm) - 5 / 4.92; 6 / 5.92; 8 / 7.9, 10/9,9; 12 / 11.88; 16 / 15.88; 20 / 19.86; 24 / 23,86
After selection of the workpiece, it is clamped in a vise, a file is removed from the end of the chamfer for proper call dies, clamping and rotationallymovements tapped without forgetting to lubricate machine parts oil.
Dies for thread cutting.
internal thread cut tap.Pre-drilled holes must be smaller diameter of the thread you need.Extract from the table diameters of drill bits for drilling holes is shown below.

thread diameter / hole diameter (mm) - 2 / 1.6;3 / 2.5;4 / 3.3;5 / 4.2;6 / 5.0;8 / 6.7;10 / 8.4;12 / 10.2;16 / 13.9;20 / 17.4;24 / 20,9
for tapping into the part you need two taps, roughing and finishing.

Just stifle detail in Teskey and rotational movements with slight pressure threaded rough tap, tap periodically lubricating engine oil, and then do the finishing pass.The thread is ready for use.
Taps for tapping.

Tip 2: How to cut an internal thread

Many years ago, when the era of fasteners just begun, making the nuts is a task feasible only for the master of high qualification.Today, cutting internal thread is a routine operation.Nevertheless, for its high-quality performance you need to have certain knowledge and skills.
How to cut an internal thread
you need
  • Electric drill, set of drills and taps, thread gauge, caliper, table sizes metric threads.
Determine the parameters of the thread, which will narezatSuschestvuet many kinds of threads, but often we have to deal with the metric, which is characterized by two parameters - the diameter and pitch.If there is a screw, which should be cut at an internal thread , measure the parameters.Thread diameter is measured with a caliper, step - rezbomerom.Unless rezbomerom thread pitch can be measured by the following method.Push the bolt thread to a blank sheet of paper and rolling it to the thread is printed on the sheet.Count how many turns is over a certain length and divide the length by the number of turns.The resulting value will be indicative of the thread pitch.Pick on a table near the size of a standard metric threads step value.
Determine the diameter and depth of holes to be performed by determining the diameter of the cutting rezbyDlya use the same table on which defines a standard step.Seeking parameter is usually denoted by d1 or D1.Esli thread is cut in recess, it is necessary to identify and drill hole depth.It must be greater than the depth of threading a certain value, which depends on the construction of the tap.Measure the length of the blade (suction) of the tap and add it to the required thread depth.This will be necessary drilling depth of the hole.
Drill correct diameter to the desired diameter of the existing drill glubinuEsli does not coincide with the diameter of the hole defined in the table, grab near the diameter of the drill.However, keep in mind that the difference between the diameter of the drill hole and the standard size should not be substantial compared to the thread pitch.Drill a hole, make it a small chamfer drill larger diameter.
Cut thread to fix a tap in this knob, insert it in the hole, and firmly holding the tap to the hole and give it a rotary motion.Thus try to maintain a perpendicular position of the tap relative to the workpiece surface.When the tap is safe to introduce in the hole, you can restrict a rotational movement.
If the tap has two versions - finishing and roughing - first rough cut thread tap, and then finishing.
Helpful Hint
to facilitate threading into the hole you can drop a few drops of engine oil.

When tapping occasionally unscrew the tap to remove the chips.
For better thread do turn knob 180 ° clockwise and then 90 ° against.Thanks to this long is cut chips and reduces stress on the knob.
  • as the threaded tap