[drew Pilcher] needs a durable custom coil, coreless and completely flat on the side. Of course, the coil can be wound by hand, but it needs some extra help to reliably make a perfect coil with thin wire and many layers. Happily, [drew] shared his way of doing so. Perhaps not surprisingly, the key to making repeatable, high-quality coils is good preparation and tools.
The most important part is to be able to rotate the reel for winding without taking your hands off the workpiece. To achieve this, a cheap, nameless electric drill and foot pedal (made of the trigger device of the drill) form the basis of [drew] DIY winder. In order to manufacture the coil accurately, the number of turns must also be calculated. Thankfully, there is a simple solution; [drew] use Amazon’s cheap digital turn counter. This economical device uses magnets and sensors, so [drew] only needs to clamp the magnets on the side of the drill chuck.
Careful wrapping and free use of Ca glue will help ensure good results.
The spool is the part of the wire that is wound together to form a coil and then needs to be removed from the coil. To do this, drew used brass shafts, metal washers, and some plastic gaskets. A thin layer of grease is applied to the surface of the valve element to help ensure the final correct separation.
In order to actually make the coil, [drew] suggests using some amplification methods and providing CA glue. Wrap the wires as clean and tight as possible, and apply CA glue during the process to fix the items. This requires some practice, but if the operation is correct, it is possible to really clean the winding.
For thick coils with many layers, CA glue can bond them together well, but for smaller coils [drew] likes to finally coat them with a layer of two-component epoxy resin. After setting, remove the valve core and push out the inner core as gently as possible.
What was the result? A tightly wound, durable coil with very flat sides. This is what drew needs for his upcoming Coil Gun project. You want to know what’s going on? Here you can see the basics covered.
