Advice 1: How to find the length of the spring

The length of wire from which the sweet spring, is much more the length of the spring. To find out the length of this wire, besides ruining the spring, unwinding it. It is enough to perform the calculation.
How to find the length of the spring
You will need
  • - spring;
  • - caliper;
  • vise;
  • - protective gloves;
  • protection sunglasses;
  • calculator.
Measure the diameter of the spring in a compressed state with the help of Vernier caliper. Don't add to it much effort to it, otherwise it will shrink, which distort the measurement result to decrease. It is best to measure the diameter in several places, and then find the arithmetic mean of the measurement results according to the following formula:D=(D1+D2+D3+...+Dn)/n, where D is the average diameter, mm, D1...Dn - measurements, mm n -number of measurements (dimensionless value).
Find the length of the circumference of a single turn according to the following formula:l=πD, where l is the circumference in mm, π is the number PI, D is the diameter of a single turn (mm).In fact, the revolution has not the form of circle, and oval (due to the fact that the wire has a nonzero diameter, and each coil even in the compressed state has a diagonal longitudinal section), but the elongation due to this so small that it can be ignored.
Count the number of turns of the spring (not necessarily in a fully decompressed state). Not to be mistaken, you can use when counting turns of the elastic strip, for example, of flexible plastic material. With each leap from round to round it will make a distinct click. Enough to count the number of clicks and add to them one (with the last round of the strip will come off almost silently, because they will not hit next).
Multiply the circumference of one coil to the number of turns:L=lN, where L is the length of the wire from which the retinue spring, mm, l - the circumference of one loop, mm, N is the number of turns of the spring (dimensionless value).
If necessary, use protective gloves. Compress the spring and open your not sharply, and smoothly. Protect the eye.
Useful advice
Compressing a strong spring, be careful as it can slip and cause injury. Very strong springs are better measured in the uncompressed or slightly compressed state, despite the fact that the accuracy is somewhat reduced. Take particular care if used to compress a vise or other mechanical devices.

Advice 2 : How to change the springs in the couch

Repair furniture at home is a difficult task, but doable. On the one hand, specialist furniture is guaranteed to fix a broken sofa. But on the other hand, the overall delivery of the furniture to the repair shop - a very troublesome and expensive task. With a strong desire to repair the sofa at home on their own.
How to change the springs in the couch
You will need
  • - wrench;
  • - flat screwdriver;
  • - pliers;
  • - a knife for the foam;
  • - new foam.
Before you begin to repair, prepare the necessary space. To repair happened quickly and efficiently, prepare all the necessary tools and a set of new springs to replace. Remove the rug or carpet, put a thick and dense film to protect the flooring from accidental fall of a heavy tool or item of the design of the sofa.
Start disassembly of the sofa with detaching sidewalls. Wrench Unscrew the mounting, possibly holding them from free fall.
Any convenient way to label the parts of the folding cushion of the planes on the right and left in order after repair to collect them in the correct order. Disassemble the mechanisms.
Continue disassembly of the sofa, alternately disengaging the seat back. If you have the pallet, you need to dismantle it.
To remove the covers, use a pair of pliers and pull the bracket. Avoid strong jerks, try to do everything carefully. Otherwise, you can damage or even rip the fabric covers.
Proceed to repair the spring box, pre-pulling the mattress. Take a damp cloth to remove dust and wood chips, which are usually present in abundance at the site of attachment of the spring unit to the bottom of the sofa.
Test all sofa springs. This can be done without dismantling, but experts still recommended to pull out the entire unit and to determine the suitability for further use each spring separately.
A broken spring will remove it with pliers. Installing new, use furniture foam and dense old blanket for greater elasticity of the spring unit and increases the operating life. To do this, take a knife, cut the foam and stuff them spring unit, and then cover with a blanket and secure it around the perimeter with a hammer and 30-40 mm nails so that the blanket was as close as possible and collected the springs, not allowing them to fall in different directions. This removes the main cause of breakage or excessive stretching of the cushion springs - their asynchronous work.
Is the advice useful?