Hi, I'm new to this forum and this topic. I'm a keen windsurfer but live inland and often get fed up when there is little wind or gusty marginal inland wind. So the electric surfboard is a dream toy for me. I've been watching the Onean board (still a pre-order product) as it seems to offer the best value for money at 3450 euros.
In the meantime the DIYer in me is looking to build one like others on here. I'm still not sure whether to go the jet pump route or the propeller-on-a-pod route (like Matthias_S). Currently I'm favoring the propeller but I'm unsure about sourcing a planetary reduction gearbox. The Neugart is expensive but I've found these by Banebots:
Banebots Building Block Series 220 Planetary gearbox
http://www.andymark.com/product-p/am-2879.htm
Banebots P80 Gearbox
http://www.robotshop.com/uk/banebots-p80-single-cim-gearbox-4.html
They are much cheaper at around $80 to $100 and both are available in several reduction ratios, but I'd be interested in either the 4:1 or 16:1. Probably the 16:1 so I can use a higher KV motor (higher RPM), for example a water cooled inrunner such as the SKYRC Proteus Water Cooled X524 600KV motor. Also both are advertised as being able to handle a 'recommended' maximum torque of 85 ft-lb or approximately 115 Nm. As a comparison the Neugart PLE080 at 4:1 quotes 115Nm nominal and 184Nm maximum, and the Neugart PLE080 at 16:1 quotes 120Nm nominal and 192Nm maximum.
If Banebots mean nominal when they use the phrase 'recommended maximum' then they are indeed equivalent to the Neugart. I'm just wondering how they can achieve an equivalent product for a much lower price, surely the quality is poorer or is it just that other manufactures charge a premium for a niche product? Has anyone any thoughts? I'm thinking that it might just be worth taking a punt on the Banebots gearbox...
Anyway it's really early days for me on this project, I've not purchased anything yet :? well apart from my existing windsurfing boards

. This topic is great and has been the single most useful resource on the internet for me, so thanks guys. The 'failures' are as useful to hear about as the success stories.