Apple Mac Mini M2 SL (Super Légère)

Partially inspired by the Snazzy labs M1 build (which made the smallest Mini possible) , another case mod for the M2 Mac Mini, this time focused on weight and power options. A failed attempt at creating a OSX based do-it-all mobile compute module.
While the Snazzy build went for a minimal size desktop, removing the original rear panel to reduce empty space, my build retained it for simplicity and as a result, still has empty space inside. Where the Snazzy build used a total of 6 separate 3D printed parts, I did it with one- a single housing sleeve with integrated antenna holder and mounting points. While the result is significantly larger than the Snazzy labs, the aim was light weight over small size.

Mini SL Ready to install with antenna already in Sleeve

I have been using Macs since almost the beginning. I started using an iPad as my daily device for meetings and I started using stick PCs as a way of adding a full computer to my bag with minimal weight gain(replacing a laptop). Sometimes I need access to specialist PC software, sometimes its just desktop Outlook or Excel.
The stick PC was successful in the day, while it could be slow, when addressing a certain need, speed isn’t vital. The let downs were lack of storage, no internal network port and limited USB ports and power.

MiniSL alongside (its competition) the Mele PC

As I downsized my laptop to the excellent (but slow) Macbook 12″, I needed a better compute device to replace both the stick PC and a virtual PC. I moved to a NUC at this stage, selecting the new 7th gen i3 with its low TDP which allowed smaller PSUs. While the NUC added weight compared to a stick PC it gave me lots of power, storage, HDMI 2.0 (unusual at the time) and powerful USB ports (doubling as a USB Charger). It has served me well for 6 years, it found use not only directly connected to an iPad but also to drop places and remote into (I often need to be on two air-gapped networks).

Always looking for better solutions and the possibility of moving to OSX, I started considering replacing the NUC. Some of its failings are Duet display- while once reliable is completely unreliable now on PC. Getting connected to the NUC other than via remote desktop can be challenging. The NUC was also stuck on windows 10, while not really an issue, it highlights that its an aging machine.

Choosing a Mini
When the M2 came out, I did look at whether it would replace my quad core i7 2012 mini but the prices of apple storage is insane. In my view a desktop should have sufficient internal storage, its completely ridiculous that my 2012 Mini came with more storage than the 2023 Mini (it came with the base 500GB drive, most selected the 1TB Fusion drive option at that time). My 2012 mini now has 8TB of internal storage (in the form of 2 x 4TB Samsung SSDs). The limitations in what virtual machines the M2 can run is also a serious issue for for my main machine. I need to run not just Windows but other VMs for appliances and OS. So storage and processor ruled it out as a primary machine.

Some of the things I hate in the design of the M2 as a desktop make it a great mobile device- the lack of expansion makes for small components. It became easy to select the base mini for my intended use as a mobile unit. . The smallest processor reduces powering issues, the base storage limits cost (for something I am hacking)and its is the best value. I did consider an old M1 with its slightly lower power consumption, slightly lower cost but I didn’t think it was worth it for a much older machine.

This is a first print from a 3D design, so not without flaws/observations! I am actually quite happy it didn’t need any modifications at all. It was designed in Autocad and printed using MJF technology with PA12 material at a commercial lab (Weerg). It features the same mounting points as the Apple chassis and the mounting points have guide holes for a M2.5 tap (so its held in place with the standard two PCB screws.
The housing includes a sleeve above the speaker for the antenna.
While my initial thoughts were to retain the fan, after running the Mini as a bare PCB for a few weeks and watching temperatures, I decided to delete the fan as it was running so cool.
I decided to keep the heatsink shroud and match the housing to it, the intent being that hot air would exit from the case rather than circulating inside.

MiniSL with its exposed heatsink

For powering the mini, I wanted a solution that gave easy access to power and didn’t add weight. There were 3 main powering solutions that I chose.

POE- where I work and at home I have easy access to PoE+. While 60W PoE++ exists, its not common on switches and PoE extractors tend to be physically larger, I therefore used a 12V 2A PoE extractor (30W).

USB-C PD- I have to carry a usb-C power supply as it is, and I generally carry an Anker PD-1, which is 30W and super light. I found USB Power cables that break out USB-C to either 12V or 15V. I used 15V as this is a more common PSU Specification.

Battery- To use in my van, and potentially mobile, I wanted to be able to run on lithium 12V batteries (so up to 14.6V)

Power is terminated on a 0B Lemo chassis connector. I use a lot of these connectors in my van and for other 12V power connections. This one is 15V and the wrong gender (compared to my personal standard) so I used 0B as opposed to my usual 1B, which prevents accidents. Its a very nice compact, locking connector with excellent cable strain relief and reliability.

The LED is relocated to the side of the heatsink, held on with 3M VHB tape. The plastic holder requires a little trimming. This allows the LED to be viewed via the cooling vents.

Results- Weight
More than size, the aim of this project is light weight. Coming in under the NUC makes it a rough success. I say rough because the NUC has an M2 SSD and twin RAM slots, so it should be heavier. The Mini I suspect is a little porky due to the relatively large heatsink, I have forgotten what the Nuc one looks like but I think its probably smaller and the NUC therefore more fan dependent.Its also only a rough success in that the MiniSL is 1.8x the weight of the Mele, yes the SL has more than 1.8x the performance but CPU/GPU aside otherwise they are similar. Same 256GB Storage/8GB RAM, Both have WiFI 6 and BT5 (with mini slightly better spec), both dual 4k output, both passive cooling (although the Mele won’t overheat). The Mele also has a much more practical Micro SD card storage expansion (the SL needing a USB stick to achieve the same which is a pain when throwing in a bag). It lacks one USB-C port (and thunderbolt + Alt mode displayport)

The MiniSL now weighs less than the aluminium housing of the standard Mini!

Bare Weights
Mele PC bare weight 188g

Mac Mini M2SL bare weight- 344g

Custom 7th Gen i3 NUC bare weight- 406g

2017 Macbook 12″ no PSU- 937g

Standard Mac Mini M2 (Apple specified weight)- 1180g

Just the Mac Mini Chassis, the aluminium, no PSU, no power light, empty shell -497g

MiniSL powered with Belkin 45W adapter- 15V PD

Mains Powered Weights
Mele PC weight based on already carrying a USB-C charger for the ipad- 188g

Mac Mini M2SL with cable based on already carrying a USB-C charger for the ipad- 389g

Mac Mini M2SL with Dual output PSU and cable- 476g

2017 NUC i3 with PSU- 580g

PoE+ Powered MiniSL- 12V 2A PoE extractor

PoE Powered Weights
Mele PC with PoE+ PSU- 242g

Mac Mini M2SL with PoE+ PSU- 475g

(virtually the same as with a Mains PSU, slightly higher cable weight due to using a 2-part cable for DC powering flexibility)

Results -Power
USB-C is really quite cool as a universal power supply and a generational jump over the 5V USB-A power. I already have lots of devices that use USB-A as a common power supply, sometimes with DC-DC conversion to get up to 12V. With USB-C one simply needs the right cable and a PSU that will output what is needed (and unfortunately some don’t). I had to upgrade the Anker PD1(which doesn’t work properly at 12V for either the Mini-SL or the Mele) to a Belkin dual output 45W adapter. This powers the Mini happily in all scenarios.

One sole issue with multiport PSUs is some drop power when re-negotiating. I have a Quad output RavPower charger, which works great but if anything new connections or disconnections are made it will drop power briefly, which will cause the MiniSL to reboot.


PoE power was partially successful, partial fail. On PoE the MiniSL boots and will run for days. I can even max out the processor and its fine. If however, I run Geekbench it will brown out several minutes into the CPU test. It does not seem able to provide enough power for tasks which use both CPU and GPU.

Results- practicality and functionality
A combination of Apple Silicon and Ventura is just not practical for me. Even some OSX apps don’t install.Lots of playing around with windows ARM reveal that to be a real mixed bag. Its pre-release software (so no blame to be laid at Microsoft’s door). While I understand the differences (and this is a metaphor not a direct comparison) its a bit like going back to emulators rather than virtual machines. Some stuff works but its hit and miss and some vital software I just can’t run.

I have roughly the same hit rate installing a windows app with Wine as I do with windows Arm. Some installers just won’t run on ARM due to dependencies and/or the checking of dependencies. Anything requiring drivers is a no-go.
For me the end result is a powerful cool running machine with no real use case.
After creating this MiniSL, I bought the Mele PC, which while a lot slower, is a lot lighter, was a lot cheaper, will run anything I need. It also runs perfectly from PoE. It will become my main mobile compute device.
I keep my Mojave 2012 quad core i7 with its dual internal 4TB SSDs and 16GB RAM as my day to day office machine! Its flexibility trumps the speed of the M2 for me.

The Mini will become a bit of a laptop replacement for use in specific use cases and as a PoE media player. I expect it to get a fair amount of use as a desktop for the van.

For anyone that wants to replicate
This housing sleeve can easily be printed by downloading the STL and sending it to a printer. All it takes to install a Mini to the case is a M2.5 tap and a PCB with the DC presented on a connector of some sort. I did not modify the case in any other way.

A word of warning to anyone who wants to try this.  The power button has a thin ribbon cable that runs by the corner of the shield.  Its easy to catch this when manhandling it in and out of the case.  i broke mine!  Set to auto power up now (after I booted it by shorting the switch).  I recommend re-routing the cable away from the corner as it can now pass in the void where the PSU was. I managed to replace the Apple cable with a generic 0.5mm pitch 6-pin ZIF cable as the part seems completely impossible to find.

STL Link

Eurovan- LED Third Brake Light Conversion

Solving the problem you didnt realise you had!

I have curtains on the back window and you always had to manoeuvre the curtain around the 3rd brake light. Not that complicated but I was looking at swapping the curtains to the Van-X ones, which are stretch curtains. A quick measure up suggested that the 3rd brake light was going to be a real issue with the Van-X curtains.

The problem. The original rear cover mounted to the light housing blocking the curtains. LED board in the foreground.

I have been doing a bit of 3d printing recently, so after doing a bit of examining of the brake light unit, I realised that if I could put a LED board where the Hella reflector board clips in, I could make the curtains fit.

First off I found a 3rd bake light LED replacement that had an LED board the right size. Using an off the shelf module just seems so much easier as I know it meets all the right brightness requirements. I found a “GSRECY Red Lens Rear High Level Centre Stop Tail Third Brake Stop Llight Lamp For Transit MK7 2006-2013” on amazon.

Transit LED board on 3D printed back plate compared to the original Hella bulb unit.

I then designed a 3d printed backplate to mount as the Hella reflector board does and to accept the new board. It had a raised section to allow the board to mount without the cables getting in the way. I designed clips to hold the board in place (but the top ones hit the red perspex so I had to remove them and glue the board. There is a cable access hole with a cover on the back side (to make the cables exit flat against the panel) and some loops for zip ties.

Its all printed using MJF printing.

Back of the plate with the two locating areas to mount into the original clips.

The board clips in nicely and makes the 3rd brake light just the right depth for the curtains. It is attached just with butt splices, would rather have incorporated some form of connector but couldnt think of a way to make that work.

The final installation. Messed up when attaching and forgot the heatshrink so the cable could have been a bit cleaner! The original rear cover locating pins now remove.

Solar Part iii

We had a wonderfully unseasonal bit of weather at the weekend, so I took advantage and fitted the new solar panel.

250 Watts of Panasonic HIT

Its a Panasonic HIT 250w panel, which happens to be a perfect size to go on the central section of the roof. It replaces the 4 x 50w Lensun semi flex panels I had on before. The Lensuns lasted about 2.5 years after which two of them delaminated and lost their top cover. Underneath they were a sticky rubber, causing dirt and water to stick to them. I lost one out of each series string (two series strings in parallel) so the performance took a real hit.

Time took its toll on the 4x 50W Lensun panels. Having lost their top cover, water would pool on them and they lost a lot of power. Obviously the two knackered panels are in the centre.

I chose the Panasonic panel for their width and after the experience with Semi-flex panels, I wanted to try a rigid panel. It hit my power and size requirements (same or more than the lensun in terms of power and baiscally the same size). It has a useful 44v output (similar to the lensun parallel/series arrangemnent) helping to keep feed cable sizes small.

I used the Photonic universe mounting brackets/wind deflectors to mount them. I wanted a wide mounting surface and to stop wind going under the panels, both from a cabin noise and from a flight risk point of view. Using the brackets was not a simple task at all. They are designed only for 600mm panels, so I had to use two pairs cut to length (which took quite a while with a hacksaw).

I used some of the spare off cuts to make central brackets (both to hold panels but also to give them some central support). I also added some front support brackets, as side brackets get a solid

The roof is curved, and more at the front. The two bracket halves are at angles and I had to enongate the bolt holes in them to allow for some angling.

The main contacting parts of the brackets and the side brakcets are all bonded on with Plexus MA310 structural adhesive, which is recomended for use with the ASA roof . Where I still had some space to fill due to the angle of the roof , I used Sikaflex 512 to fill the remaining gaps. All the bonding areas were sanded and degreased first.

I was concerned with the extra weight (15kg panel) and compared to the lensuns, I did put the panel much lower on the roof so more of the weight moves around the pivot point. The struts seem to handle it ok. They can’t hold it at the part open state (but they couldn’t before either). It goes all the way up and stays but think there is a reduction in tension now and I can pull the roof down a lot more easliy (it needed a bit of a tug before).

Of course the rigid panels add a small amount of height compared toi the lensun panels before. I hope the neater roof will have less wind noise and be more robust though.

Winnebago table Mk.3 (freestanding)

Another long term project that I think is possibly at a conclusion. The hunt had been on for a table solution that doesn’t require taking part of the bed (I like to sleep in . . . .). It seemed a waste to have this table in the van that couldn’t be used outside of the van.

My Mk2 solution was to replace the old single leg with two off the shelf fold down table legs. These could be used either in the normal way in the van or in combination with some bolt on legs.

I am a fan of the 15mm rod system that gets used for video gear. I discovered it years ago when i used them to make a motorbike stand!

For Mk.2 I created a pair of legs using 2 x 400mm +300mm rods. I added bracing with two 200mm rods and the end caps from the 400mm rods. The legs have generic 15mm rubber stoppers/feet. To start with I used Smallrig tube clamps mounted to a carbon fibre interface plate and mounted to the table.

The end result wasn’t entirely stable, primarily due to the off the peg legs which had way too much side to side movement. I decided that there was mileage in the original idea and worked on MK3. The clamps I had used had a very small contact patch so had movement in them too, so I looked for a better clamp.

I found what looked like a more stable mount in the Smallrig dual clamp (1943), which is designed to take a dual rod but I didn’t let that small detail bother me. It seemed to offer a flat mount and 3 mounting points. When it arrived I found that one mounting point has a recess, so I found 2mm washers to space that out. Another washer to fit in the tube socket for another bolt and hacksaw the dual mount in half! Mounted to the table with bolts and structural adhesive and it seemed more stable but the other end was still wobbly so I ordered up another set of rods and another two dual mounts.

The end result, I put 3 leg mounts on one end, so I can use either a single or dual leg in the van or 4 legs out of the van. 700mm legs with 400/300mm rods joined. Sockets from 1943 clamps cut in half and fitted with stainless knurled m5 knob.

Two side bracing bars from 2 x 200mm rods and Smallrig 1104 90 degree brackets. The 1104 brackets have one of the two bolts replaced with an allen key bolt so that only the clamp for the upright is adjustable. Mounting clamps for all rods fitted to the underside of the table.

Another Eurovan new switch plate.

A lot of the eurovan blogs out there end up having a new switch plate of some sort! Times change and we need new fuctions. After getting mine, I originally modified the original by cutting in a couple of switches for the fridge and fitting 12V, USB chargning and a switch in place of the redundant 110v outlets.

My issue with this set up was primarilly that the USB and 12v cables were by the opening part of the fridge door, which always lead to cables trapped in the door. I could have re-hinged the door but the door was correct as the passenger could open it and get at drinks while we were moving. I also didn’t have a switch setup for my router (which lives under the sink)

The secondary issue is that in these coronavirus times the van is my shed office. To plug in my laptop I currently have to plug in USB-C into a modified cigarette lighter unit and plug that into my 12v outlets. It is not only a bit ungainly but I also keep running out of outlets on this side of the van (using another for wifi link and another for a NUC). I wanted to install a modified USB-C adapter

I started CADing up the plate probably 2 years ago and it got re-picked up every now and again. Everytime slightly different. I wanted to get a proffesionally made plate from the cad made out of metal but getting someone to do it was problematic. In the end I gave up. Something composite and home made is a bit more in keeping with the van anyway!

Made some carbon fibre plate and transfered all the measurements from my cad to the plate by hand. Took my time and tried to get all the holes as accurate as possible with a handheld drill and a dremel. Should really use a pillar drill but I have too many tools for my flat as it is! One of the nice things of composites is they are a lot easier to cut than metal.

Not sure what everyone else finds but my Winnebago framework is far from square. Plate had to be taller on the left to the right. My plate also has a straight line from one side to the other, which shows the bow in the metal work! Its also not flat as they never bothered to sand down the welds. . .

Left to right my plate ends up with

  • 2 x 12v direct power outlets on Lemo 1B
  • Switched Dual USB A power outlets with volt meter. Dual USB-C outlets with top delivering 30w for laptops, lower 18w for phones etc. (Its a pass through connector connected to an Anker charger modified to convert from cigarette lighter to cable input)
  • Gap for future sockets
  • Locking power switch for van 4G wifi router and associated bits
  • Fridge power
  • Livello 9-LED LPG monitor
  • Stock test switch
  • Stock levels board but with LED holes for water only
  • Water pump switch

I was tempted to get rid of the factory meters completly but seemed silly to chuck it away when i would have to recreate its functions for the water. The voltage and LPG are now hidden away as they serve no function any more.

Winnebago Gas struts in EU

I struggled to find all this info, so hopefully this will help others

Pop Top Struts

Mine was fitted with Nitrolift GS10-22-300-350. This tells you it has 10mm shaft, 300mm stroke and a 350mm body with a 22mm body diameter. It does not tell you about the rod ends or the force. The ends are 13mm ball sockets (which on nitrolift fit an M8 thread). The length of the ball sockets is 30mm from end to ball centre. In the UK SGS sell these and the socket is code B14.

Choosing a force. . .

What I found is that the stock seems to be 100lbf (444N). Heavy duty ones are sold at 110lbf (490N) and 120lbf (533N).

First off I got a standard which was dumb as I have solar on the roof. I had no idea what was fitted to my van initially and they were stronger than 444N.

I probably have about 10kg on my roof so second attempt was a 500N (112lbf). This works out much better but they still struggle to hold in the partially open state. I would go for 533N at least next time.

There are YouTube videos that show how to compress the struts with a ratchet strap and a prussic loop (loop of rope) this is really easy to do. Propping the roof is the bit that takes the longest (just finding something a good length). I used some camera rods with some books to space it all out.

Kitchen unit struts

The original struts had markings:


Google says this is a 40lbf (178N) strut with a 2″stroke- length between 5.5″ and 7.5″ (140-190mm). Think its 10mm ball ends, 6mm rod diameter, note that length includes ball ends.

At the time I got the van the struts had completly failed and I couldn’t find a direct replacement. I went for some a little shorter that were easily available on ebay and moved the mounting points. These were 80N small kitchen struts. They kept the lid open (apart from on a slope).

Eventually I put a magnetic knife block on the top so up-rated the struts and went back to the longer length.

I can’t find a UK 51mm stroke unit. Closest is under or over (40 , 60mm). Note that lengths of nitrolift units don’t include the ends.

Nitrolift GS6-15-60-100 rated at 160N (160mm long, 60mm stroke)

Plastic 10mm M6 ball end – 18mm length end to cetre. (complete length 196mm)

I managed to install these with the brackets back in the original hole. Took a bit of force to get them on due to the extra lenght. Work fine now, top does not raise by itself but will hold at any opening.

The knife block actually holds the knifes even over bumps etc. The block I bought wasn’t up to the job so I bought some Neodymium magnets of the same size, glued them on top of the existing cheap ferrite magnets and added spacers.

Roof Vent

Another of the Winnebago Eurovan issues. . .

Like many others I had issues with a broken roof vent. When I got it, the roof leaked like a sieve and the mounting points for the middle chair used to fill up with water. Inspection showed many issues. The hinges had rusted completly through in some places, so it didn’t shut at the front. The latch at the back was also repaired and so it didn’t shut at the back properly either.

First thing was to fix the hinges

At this point it was kind of usable, but still leaked, just at more managable level. It still had to be taped shut most of the time, which was a pain. Sometimes would start coming off driving, couldn’t open without removing etc. etc.

I hunted for a replacement. Tried everywhere to find something of the same footprint without luck. I had seen posts from others where they had fit larger, RV style hatches. I even had one delivered but returned it because it was a) really plasticy and flimsy (not that the original is sturdy) b) would add about 100mm which further limits what carparks I can get into.

There are things that are nice about the original vent. Its lightweight (I measured at 1.3kg with trim)and its low profile at about 20-25mm high.

Roll forward a year and I found a new contender. The Lewmar Low Profile marine hatch, size 20. This is roughly the same size, claims a 25mm height (which is only partly true as it doesn’t shut flat by design) and has a stated 2.3kg weight. It is much sturdier than the old one and has a 8mm thick acrylic top. I am sure you also hear the difference in sound transmission but perhaps I imagine it. It has a nice locking position partially open and then a friction hinge that holds it at any position (it goes a fully flat). It has a tinted glass so lets more light into the van (both a good and bad thing!)

Due to the thickness of the trim on the old one, the Lewmar actually presents more open area but its thinner, to such a degree that the bolt holes are not covered by the roof plastic, as such it takes an interface plate to mount it.

First was to take the old one out, much easier than I expected, gentle pull and out it came (remove internal trim first)

First created a temporary wooden interface plate out of scrap ply. It was basically the same size as the old vent with a cutout for the new. It allowed me to drill the 4 holes in the roof and do a test fit. It was a good idea as I decided it was too small, made it about a 10mm bigger on front and back to give a reasonable bonding surface. The original vent had only 10mm or so.

The final plate, constructed out of carbon fibre at the larger size. It is bolted on left and right and bonded all the way around to the PSA roof using Plexus MA310 structural adhesive. The vent is then stuck and bolted to the interface plate using Sikaflex.

My struts for holding the roof up are currently at 500N (112lbf) which work fine for opening the roof but still struggle at holding it open at the safety strap height.

2020 update, finally made an internal trim for it. Basically an interference fit and a carbon fibre plate as normal.

Solar (pt2)

So onto phase two and almost complete redesign of the charging, storage and generation system.

As with a lot of this build, cash flow dictated a step by step upgrade and even after all this time, some of my planning wasn’t very forward thinking. . . .

Step one was to get more visibility on what the solar panels were doing. I knew it wasn’t enough but I needed to know more. I went with the Victron Energy 75/15 Smart solar MPPT controller. This gives historic monitoring and Bluetooth display of generation, voltages etc. On phones and Macs (not PCs weirdly). They have a fully configurable charge profile (for lead acid/Lithium) which worked with future upgrades.

Next up was the solar panels. I wanted more, the question was how to fit more on the roof. I found that Lensun sell semi-flexible 50W panels that are roughly the same length as the width of the central section on the roof. This allows me to easily go to 200w and I connected the panels in a series/parallel config (48V system). Parallel panels are meant to be more resistant to shading, series gives you an earlier start to charging, combination hopes to surf the middle ground!

There were other reasons I went with the Lensun. Having previously had a cheap ebay panel, I wanted a higher quality panel but still wanted to stay with the semi-flexible panels. The semi-flexible panels are notorious for not being the most reliable but they are lightweight and low profile. Lightweight means less issues with the roof struts (think they would need upgrading for extra weight). The lensun claim a better construction and do have aluminium backing. They have a golf ball type surface which they claim helps keep them clean, which for the dusty environments the van sees is important to me. The junction box also appears much more robust. The cheap ebay panels have a junction box with a thin profile and I was always concerned that wind and vibration may be one of the faliure modes for these panels. The lensun panels have a much wider flatter box.

Without any doubt the traditional glass panels are more robust but the cost of additional height and weight.

I went the messy above, clean below install route. I have seen lots of beautiful roof install pics where the solar cables go straight through the roof and are dressed inside. I wanted to keep a single roof penetration and keep wiring inside the van invisible, so it’s not invisible on the roof!

In retrospect, I would have installed them all lower allowing for me to fit 300w by covering my broken roof vent (as an option, still looking at ways to get that working again).

I have seen others fit 300w on these vans but only by fitting the panels over the gutters rather than between them. The gutters and roof hatch otherwise limit you.

Next step was storage. The flooded lead acid 110AH battery was massively struggling to give out anything like its 1320Wh plate figure. A guess would put its real capacity more like 500Wh.

I read more and more into the Lithium batteries and although the cost is high £1000, the promise of a true 1kWh+ storage in the same space with less weight was alluring. The other factors are the reduction in round trip energy. In lead acid charging the last % is wasteful, so lots of the solar energy is lost. With lithium it more or less all goes back so your overall solar energy requirement drops. I found a bloke selling off 130Ah lithium Reion batteries from a failed EV project for £300 so I bit his hand off.

So at this stage I had updated the solar, solar charger, battery. Next was dealing with the charging and monitoring. I had done one winter trip with the lithium and relied on just turning alternator charging on and off with guess work as to charge times. Far from ideal. At this point we are in the world of trying to integrate a third party Lithium battery into a Victron Energy system. The solar charger worked fine but one has to find a way to make a BMS for the Reion.

I went the option of using the Victron Lithium split charge relay Cyrix-Li-ct and installed their BMV-712 battery monitor to use as a BMS. This has a relay output. Initial idea was to set this to cut the alternator charging when the capacity reached 95% (using the solar to do the remainder). Unfortunately you can set the relay to work on low state of charge but not high. Instead the relay is set so that it disconnects if the battery hits its float voltage and if that happens, it won’t start charging again unless the voltage drops considerably (level can be set)

So far I pretty much manage to run on solar alone for most of the year, I have a switch to disconnect the split charge that is generally turned off apart from winter months.  I have generated nearly 700wh/day in summer, can struggle to hit 100 in winter.  The fridge is circa 2-300wh.

And that for now is that! Some wiring modifications were included as well but I will cover that separately

A little review of the Winnebago Eurovan

A lot is said of the Winnebago eurovan and I want to address a few bits of it. There are a lot of things that I think Winnebago did well and lots which is not so good.

The gas (LPG) tank


The roof

-Much hated there is lots wrong but there are also some really good points.

-Canvas tent

Probably as much the age of the van as anything else but I really like having a canvas as opposed to a nylon tent. It’s the same with real tents, canvas is great because it breaths but awful because its heavy (if your hiking). Works better to me than a modern tent.

Windows in the canvas tent

I don’t know why no-one else seems to get this right. Big windows that open to reveal a mosquito net beneath. Van lights attract bugs, this seems like a no-brainier. Unfortunately if you look at lots of modern pop-top tents they dont have this instead having a useless see-through layer under the window (I suppose they allow light not wind but getting air in is also useful).

The 3 big windows are also surprisingly not common.

The roof vent also seems like a nice idea but poorly implemented. I looked to swap for another modern vent but they are all 100m high. The original one is more a sunroof type vent, no extra height and this is really important to me.

Yes, the actual plastic roof is poorly done. I remain unconvinced whether elevating only the van and not the cab is the best idea. Mine is craceds as many are. They don’t latch down nicely.

Insulation (or lack therof)

It seems there are some real differences between how the brits and the yanks build campervans. In the UK, insulating a van is something that is done first, everything has insulation. Aircon and heating? Much less common. Yanks seem to be the other way around. I was always planning on having a heater and it is seriously useful. My van actually has broken cab heating, so the rear heater is actually useful for warming the van up generally too!

The aircon has been a nightmare but at times really useful.

Build quality (or lack thereof)

The van is put together with metal self-tapping screws. No threaded inserts etc. If something is bolted through a surface then the bolt on the other side is not captive. If it goes through the floorpan, it takes two people to remove a bolt, one either side. No bolts have Mylar inserts when they should.

Lots of bolts have self tapping into plastic (heating vents etc) which just fails.


This really does follow the build section. The wiring additions are poorly done with no proper colour coding (black, green or purple are the colours). Tracing wiring is very diffult and mine isn’t wired as per the winnebago diagram (similar but clearly varied over the years slightly.

Off grid capability

The LPG tank is awesome. Can still travel on the Eurostar. Filling with gas is super cheap and lasts ages (even in winter). No issues with different bottles in other countries. If really going to need to top up abroad bring LPG adapters. Building an off-grid setup today, solar and compressor fridges are where most of us go but this wasn’t an option back then.

The tank is kind of dangerous today. Very easy to over fill even if you follow the (misleading) eurovan manual. Apparently there were warnings on the tank at one point. New tanks stop filling automatically, these old ones do not.  I am not sure its possible to actually fill it up the way intended in a petrol station (involves opening an overflow valve).  I watch the meter now (which I had to replace).


Easy to remove, sliding rock& roll bed!  Hits a lot of points for flexibility, even if its not the best implemented in the world.  I didn’t realise until I had the van that the bed just rolls forward and out on wheels!  Not done it yet but makes putting a motorbike in the back a possibilitu


much hated and really not complete.  The rear wardrobe has dual sliding doors and a door always seems to be in your way.  Wardrobe good for hanging a few small bits only.  See build threads

Middle lower cupboard is deep but awkward

middle bathroom cupboard has no shelves.

Front cupboard doesnt open if the bed is down.