Is commonly in use during soldering, welding – in case if the
hand/fixing device is missing, or when there is a need to keep something
a long time (glue work). Actually it is the well-known device named as a
forth hand (even if it is called as a third hand). Thåre is no drawing
available, because it is not needed. Everything is shown on the picture.
We should take the base construction with certain large weight.
Cross-shaped construction should be prepared on beforehand using the
pipes D=8 mm, which needs to be inserted in base. There are balls
welded, on the edges of construction. Then should be inserted the next
pipe of D=6 mm, the next pipe of D=4mm. The last pipe is of diameter,
selected due to the reason that it will be applied as a clench. Normally
I use the typical clamps from voltage tester. As usually, magnifier lens
should be fixed to the middle joint, or another magnifying device. So I
use the common magnifier which was in sell for grandmother, to hand-knit
the socks. But there is needed to make a frame, using pipe which has
been cut in longitude direction.
While manufacturing joints, please keep even distance between holes. Put two semi-finished parts together in vice-grip, the drill holes, having fixed the parts. After that, make the parts shaped.
The diameters of the holes are not specified here, it depends on ball sizes you have available. Diameters of the balls are of reducing values from joint to joint, similar to situation with diameters of pipes. The main condition is – to avoid the tight contact of pipe to hole edges.