Tin dispensers for home construction.
When soldering larger projects, it is not practical to have the spool of tin laying around. It will either roll off the table, or it will not unroll fast enough. Some companies like Conrad or Reichelt offer solder unroll stands. But these are rather expensive and these unroller stands can easily be made at home with some scrap wood and metal. Look at my own tin unrollers below.
Version one: the Flak.
The construction is easy:
Now mount the spool of tin on the stand. The bent nail is needed to prevent the spool from slipping off the
support when unrolling too fast. Look at the side of the unroller.
Many times, the tin will tend to roll back when you let go of it. Therefore I took a piece of thick solid copperwire. I bent it into shape as can be seen on both pictures. In essence, it's an eyelet, supported by two beams of copper. The tin goes through the eyelet, which prevents the tin from unrolling in an uncontrolled way.
The picture on the right was taken with the flash. The tin-guide is now better in view. You can also see a second purpose for the unrolling guide: when in rest, the tin-wire is wrapped one turn around it, so that the spool is locked and cannot unroll due to random actions on the workbench.
You figure out why this model is called the "model Flak". ;o)
New, leadfree, solder.
Lately I acquired new RoHS compliant solder. It doesn't contain lead so it's a pain in the neck to solder. And
the spools are from another supplier: Edsyn.
Edsyn ship their tin on compact spools. At least: more compact than the spools made by Felder and Stannol. Felder spools have a core with a bore of 25.4 mm. Whereas Edsyn cores have a bore of just 11 mm. So the Edsyn cores do not mate with the Flak solder unroller stands. Time for a new design!
Version two: the twin towers.
On the right, you see the new design. I called it 'Twin Towers' as a small tribute to the two World Trade
Center towers that are no more. The design of this solder unroller is extremely simple. It's made of one piece
of construction plywood and two pieces of aluminium pipe.
What we see in the picture is, from bottom to top:
Construction of the twin towers.
On the left, we see the base of the Twin Towers solder unroller. Simpler than this, things cannot be made. You
only need three parts of scrap material and a power tool with a suitable drill. Commence as follows:
Above, you see the Twin Towers loaded with one (left) and two spools of tin (right). The towers are not
finished yet. We still need some kind of wire control. So I made the double rectangular wire guide. This will
allow the wire to move freely in the vertical plane.
Again, the wire guide is made of solid copper wire, 1.3 mm in diameter. After bending the wire and soldering the braces, two small holes were drilled in the side of the plywood. The wires snugly fit these holes and no glue is neede to fix them.
As you can see, I applied an offset to the position of the wire guide. Otherwise the right sided spool had difficulties rotating. Or I would have had to make a second wire guide and mount that on the opposite edge.
I did a preliminary test and the spools rotate very easily. The tin comes off the spools without any effort. The only disadvantage of this design might be wire entanglement. What will happen if the bottom windings of a spool are removed and the spools rotates back a few millimeters? The the upper windings get a bit loose from the coil and they might fall down, thereby entangling the spool.
This was a real problem at Ushio where we used 0.03 mm Tungsten wire on large spools. I doubt, however, that this will happen with solder wire of 1 mm thickness. Time will tell...
Page created June 2000,