Thanks for the kind words, Phil.
Dan, do you have any preferred waterproof switches in mind (uk preferably)?
I don't have any I can specifically recommend, but would suggest you start your journey at your local full-service hobby shop devoted to R/C (radio-controlled) models. That's how I tumbled to my favored Deans connectors and while at the shop I saw a number of smallish, waterproof switches that could be easily adapted and mounted to mount on a frame tube or fork blade with a cable tie. Most R/C cars are subject to the same environments as bicycles with extremes of heat, cold, vibration, wet and mud so they are well hardened against all those to ensure reliability over time and many cycles of ab/use. The kind of switch I have in mind is used to switch between battery packs, so is pretty ideal for purpose. Here is a YouTube video showing this sort of switch:
https://www.youtube.com/watch?v=yBQ4hZi0PaU Pricey at a suggested retail of nearly USD$40, they are available on eBay for about $10ppd, not so far away from a DIY solution where you have to buy the switch, pump it full of high-dielectric grease ad/or pot the electrics in epoxy, rig a boot for it, then mount it inverted by a means you create. Here's a purchase link:
https://www.ebay.com/itm/SkyRC-Power-Switch-MCU-on-off-Controlled-for-LiPo-NiMH-Battery-Voltage-RC-Car-/182742498135?_trksid=p2349526.m4383.l4275.c10#viTabs_0Available also from UK sources, I'm not endorsing this switch directly but as a type to look for; there's many options from the R/C realm that would do equally well.
I'm pretty good at making things work (chartered engineer mech/elec)
You should do fine especially with your background, Phil. So long as one is facile at wiring and the most basic circuitry it is an easy project. If you can also solder it is a bonus toward making reliable connections, particularly when paired with some heat-shrink tubing.
...but don't believe in reinventing things when others have obviously trodden the path previously.
A wise man! No need to reinvent the wheel.
Also are you still happy with the cycle2charge set up and has it delivered a decent slow speed output?
So far, it (I have two) has proven to work as well in practice as my other solutions (one The Plug 2+, three B&M e-werks), but at a fraction of the price. I oddly enough do miss the reassurance of a visual "ready to charge" indicator as shown by my The Plug 2+. I used it as a quick indicator of over-demand to see if the battery of the device I plugged in was drawing more power than the charger could supply. The Cycle2Charge just sits there and does what it does with no self-indication; my devices supply that with their own charging indicators. Again, as a practical matter it makes no difference and I have long ago pre-vetted the devices I plan to charge using "shop" tools -- digital-numeric indicators of voltage requirements and current draw, so it is just a visual I liked and now miss that really no longer does anything in practice. I remember reading an article that said "bouncing light" displays and shiny objects tend to fascinate primitive peoples, so perhaps that's why I like them too.
All kidding aside, the Cycle2Charge has done well for me in providing a useful charge at a usefully low speed as well as at my normal day and touring cruising speeds and seems to usefully limit maximum output when screaming downhill at higher speeds.
Do keep in mind, however, that no charging unit is going to work as superbly at lower speeds as it will at higher ones. The speed that translates to maximum output is just not there and we don't have a lot of power to work with anyway. I really want a 3-phase dynohub. It has already arrived in some sidewall dyamos and looks to be coming soon to naben(hub)dynamos, but we're not there just yet. Limited charging power at slow speeds was a major reason behind my "charging trailer" concept: If I was going to an area so remote for so long a time I needed a trailer to ensure self-sufficiency, then it was a good bet I would be going at slower speeds on difficult terrain and would have a challenge meeting power demands on devices (i.e. my GPS) I would be using more and longer. Since I couldn't take a second bicycle with charging system, I appropriated the trailer for those needs figuring if it was going along for the ride, it might as well pay its way. Solar also helped in this respect and I have found it to be a great augmentation for dyno-power, but not yet a consistent substitute for long-term use alone. I used solar exclusively as my off-grid means for self-generating power during my 4-month 2014 European double-crossing along with a large pile and a couple smaller ones. It worked, but a key to it working well was the summer season and my periodic stays in lodging to top up the batteries from mains power*. As mentioned earlier, the Li-Po battery in my solar panel required a full 12 hours of bright sunshine to bring from empty to full charge. Needless to say, it is easy to get the procedural aspects of a charging scheme wrong at first and it takes awhile to fully integrate it into a fuller touring lifestyle to a point where it becomes second-nature. As with any aspect of CampLife™, once you get it down, then it takes surprisingly little time or effort ecause you've already made the behavioral modifications to integrate it.
I would prefer to spend 60 euro on a charger than more than double that on the Igaro D2, although I'm happy to buy the Igaro if it provides a better solution
There is something else to keep in mind wrt on-bike chargers and that is integration -- or the deliberate lack of it. I prefer an integrated solution that remains on a single bike and is somewhat resistant to casual theft so I like units that bolt on in some way. The alternative to that is a unit you can quickly remove and stow or even transfer to another bike to maximize your value and the utility of the unit. Aesthetics come into play here somewhere as well, as does function. If you have a stem cap you really like -- some folks prefer ones with snap-in analog watches or temperature gauges (i.e.
https://stemcaptain.com/ ), then replacing that with a charging head and port can be problematic. You also want something that isn't going to put a strain on the wiring leading to or from it, so it pays to put some thought into how those wires connect and lead and whether/if it is important for you to be able to charge in the rain. With my TTTP2+, I can charge in the rain by installing it with the port pointing rearward and fitting a little "rain bonnet" I made. The Cycle2Charge's plastic cap itself allows in-rain charging provided you orient the port on the "down" side of any drips. The e-Werks are the best in this regard by virtue of their screw-together waterproof leads that have the option of terminating in a USB port wherever you choose to place it. I prefer to carry my gadgets in my waterproof handlebar bag while they are charging. This means using a "just right" length of USB lead so it is not so long as to result in a voltage drop, yet long enough to snake under my Ortlieb's over-cap to prevent rainwater (and in my case, dust) following the lead inside. There's a lot more than just output and minimum charging speeds to think about when selecting a charger, and it does pay to put some thought into the particulars before splashing out for one. Everyone's needs and requirements are different, so what works well for me in my (sometimes extreme) requirements might never come into play for someone else. Reading a lot, asking questions in advance and then sharing the good and bad after go a long way toward advancing the field because makers in this rapidly evolving market segment are pretty responsive. You can almost count on your carefully selected purchase to be completely eclipsed in efficiency and convenience in no more than four years and likely in two or less. You have to be content to pay your money for a good-enough/best solution now and then figure it will work as it does until the gap in efficiency becomes large enough to upgrade. This is a key reason why I prefer separate solutions to integrated ones so I can upgrade as needed with minimal fuss and cost. The reason behind my prejudices against embedded batteries is a little different. Those units are often sealed so when a battery begins to noticeably lose storage capacity after a couple years, it is all downhill until it becomes wholly unusable. Embedded-battery units don't continue to work as well as when they are new and when they have declined to a noticeable degree you have to replace an otherwise well-functioning unit prematurely and yet another bit of electronica goes into the waste stream.
So, hopefully some questions answered and further food for thought.
All the best,
Dan.
* I have found most lodgings lack mains outlets in sufficient numbers to charge all my gadgets in the limited time I'm staying (i.e. overnight) and I hate setting the alarm several times in the middle of the night to swap items in/out for charging serially. My solution has been to (also) carry a travel charger with multiple outlets so I can charge/top-off more than one gadget at the same time. I also carry a socket adapter so I can swap a light bulb in a room fixture for another mains outlet. Just remember most lamps are switched, so be sure you're getting power before plugging in and going to sleep or you'll awaken to find nothing has happened!
It also helps to buy gadgets that allow for quick-charging so you can make the most of power when it is available. Of course, this means carrying the dedicated charging transformer that makes it possible! With many high-powered gadgets, having to revert to standard USB charging levels of only 500mA can easily extend charging times by a factor of 2-3, even 4x. The same holds true when charging from a bicycle dyno-charger. Very few offer more than 500mA/0.5A effective output, at least during most of the time/speeds you use them while touring with a heavy load in mixed terrain. If a gadget seems to take forever to charge on a bike (provided it charges at all), it is because it is charging at a lower rate than one is used to with its dedicated mains charger. Just another factor to keep in mind.
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Apologies for any typos in the above; I think I corrected most of them in editing after posting. I typed this on my phone roadside and outdoors in bright sunlight, so I may have missed something. Communications and journaling are yet another topic for the touring cyclist (see:
http://thorncyclesforum.co.uk/index.php?board=33.0 ). I have a folding USB Bluetooth keyboard I love dearly, but the usual solution for my "production" phone typing is the stylus on my Note 4 (the last Note to be available with a user-replaceable battery). The stylus is much faster than thumb-texting and doesn't aggravate my De Quervain's tenosynovitis.
