NAMBA Propwash Web October 2022.pub

PROPWASH 14 October 2022 Rewinding the Aquacraft Motor By Lohring Miller NAMBA Safety Chairman One of the big differences in the P limited class this Nationals was changing from a spec motor class to a dimension- ally specified motor class. This was similar to the difference between the IMPBA sportsman outboard class and the NAMBA stock outboard class. Though the outside looks the same for both, it’s what’s inside that counts. Because of this we now have rewound motors starting to appear. People are worried because this means electrically modified motors will be needed and they don’t understand how to do this or whether it will be expensive. I decided to research the subject and see if I could rewind a motor. There are some great threads at https://forums.offshoreelectrics.com/forumdisplay.php?143- Motor-Talk by the master rewinder himself, Don Huff. Don was also instrumental in helping me understand the process and was very patient in explaining my misunderstandings. This article is a simplified version as it applies to the pile of fried Aquacraft UL-1 motors I’ve collected over the years. My first try is to simply get more copper in the motor with the same magnet coil pattern. Some Definitions:  Stator – Laminated steel piece inside the housing  Rotor – The shaft and magnet assembly inside the stator  Stator slots – the space the wire bundles go in  Stator teeth – the fingers in the stator the wire wraps around  Bundle – The group of wires that form the coils  Coil – the group of wires that go around one or more teeth  Concentrated wind – the wire wraps around one tooth  Distributed wind – the wire wraps around more than one tooth  Leg – the coils for each of the phases that come from the speed control Wye (Star) and Delta configurations – how the legs, labeled L1, L2, & L3 are connected; see picture