2017-11-02: Gas tank – part 1

I suspect there will be many parts to this series…

After much debate, we decided to go with an externally mounted, refillable gas  tank. This one came from Gasit in the UK, and it’s about 20 litres.

The gas fittings look reasonably straightforward, given that we’ve not done this sort of thing before, but we’ve already hit our first snag, which is that the space under the chassis where this tank is designed to be mounted is slightly different to most, so the standard mounting brackets won’t fit. So we’re having some steel angles fabricated to provide secure mounting points. More on this to come.

The space where we’re mounting the tank, and measurements for the custom angles we need to get made up.

In the meantime, we’re preparing the tank to be fitted, by spraying it with a coating of Underbody Seal paint, which is pretty gross stuff, but apparently should protect it from chips and dirt that’s thrown up off the road. Many more challenges on this front to come, I’m sure.

Spraying the gas tank with Underbody Seal paint
The strange tacky, textured tarry finish

2017-10-29: Recognisable furniture

Some things in the van that look a bit like furniture!

This weekend, we’ve made some satisfying progress in the van, with a few new things going in that make it look a lot more like a home.

The two base units that form the support for the bed are largely complete, bar a few doors. That means we have a functioning bed, a bench seat, and some fixed storage too.

We ordered some foam for the mattress, which we’ve chopped up and covered in stockinette (a stretchy, loosely-woven lining that protects the foam and helps a mattress cover slide over it).

Amy sewing stockinette linings over the foam mattress sections

We also ordered some table legs, and we’ve been trying out different methods for supporting the table top, and making the conversion from bed to bench + table manageable.

And we also have one more piece of finished furniture installed – the overhead cabinets on the passenger side (above the bench), made out of birch ply, with doors supported on gas struts, and a felt lining on the inside of the cabinet.

The gas struts hold the cabinet doors both open and closed, which means no need for latches.

In a way, the van looks quite similar to the state it was in back in August, but this is one iteration on, with mistakes corrected for, some lessons learned and everything that much more well-considered.

2017-10-19: Overhead shelf in the cab

One of the first jobs we did after we bought the van was to remove the bulkhead. We toyed with the idea of joining the cab area to the back of the van by installing swivel seats, but that’s an expensive conversion, and we liked the idea of having what amounts to a separate room in the cab. Our current plan is to have a ‘soft divide’ – likely some kind of insulating curtain, that we can draw across behind the seats, and otherwise leave the cab pretty much standard.

However, there’s a lot of vertical space above the seats that we wanted to make use of, so we fitted a shelf, faced with a wall at the back that forms a partial bulkhead above our heads.

Shelf as seen from the back of the van, with stuff holes for duvets and pillows

The shelf is made from 9mm hardwood ply, and it’s supported at the front and sides on oak battens, which are bolted onto existing attachment points on the cab body.

We used oak because these supporting battens have to take a significant weight, and softwood wouldn’t be up to the task. Also, we knew the frame would be visible, so we wanted something that looked good. Fortunately, the particular plywood we’re using here, while not the high-grade birch ply, does have one nice face, which matches the oak quite well.

Oak support frame underneath the shelf

The shelf is supported by the back by the partial bulkhead, made of 12mm birch ply, which itself hangs from bolts rivnutted to the frame of the van.

We intend to use this area to stuff in bedding when our bed is not in use, so the large cavernous space is idea. We don’t need to worry about things rolling about, and all we had to do to provide access was cut a couple of large stuff holes, with rounded edges (using a roundover bit on the router).

On the passenger side, we also mounted our MT-50 solar controller monitor, which gives us some live info on the state of the battery, power draw, and the performance of the panels.

2017-10-12: Insulation woes

Fortunately, the fine particulates in this insulation board are all organic and GM-free

The last time I wrote about fitting insulation was back in May, and it feels like the job has been dragging on since then. When you look at the YouTube videos, you see time-lapses of people fitting insulation over the course of a weekend. Maybe we could have achieved that if we’d known exactly what we were doing before we started, but we didn’t, so … tough luck, I guess.

To be fair, we haven’t spent all the intervening time fitting insulation, but every weekend, pretty much, we’ve been doing part of the job, just enough to progress some other part of the job: fitting the bench bed, or the shelf above the cab.

But the main source of frustration has been the endless trips to Screwfix to buy more materials – and in particular, expanding foam. This van eats the stuff.  A quick check of my van expenditure spreadsheet reveals we have bought this many cans of expanding foam:

That’s 14 cans.

They’re 750ml each, and the packaging states the contents will expand to 35 times the original capacity. So – ignoring wastage, of which there has been a fair amount – I calculate we’ve sprayed over 26 litres of foam into the cracks and crevices of this van.

Anyway, we’re almost done.

Insulation is one of the most controversial topics on the van conversion forums, with many a certainty bandied around. Our original plan was to use rigid board for the bulk of the insulation, with expanding foam to fill the gaps. I still think that was a pretty solid plan, but I wish I’d known at the time we’d by spraying this much of the stuff.

2017-08-06: Bench bed and cladding test

We’ve been busy on various jobs since I last wrote, mostly trying to get some basic components built in prototype form for we can take the van on a short trip and test some things out.

Almost every design/build problem in the van is a chicken and egg problem. And we tie ourselves in knots trying to decide which part to commit to, so that we can move on. The interaction of furniture, cladding, and electrical supply is one such problem.

Since we had to start somewhere, we took the passenger side of the van as a low risk first step.

Bench bed

I started by building a simple bed frame. It’s mostly self supporting, with the legs nearest the wall bolted to the van body using rivnuts.

Bench/bed frame

I set the frontmost legs back from he edge of the bench so that, when seated, you can swing your legs back. The front and sides will be panelled with ply, as will the top. For now, we have a piece of MDF on top to use as a test. The front edge of the bench has a 2cm lip which will form the middle (longitudinal) support for the bed. The other half of the bed will be removable, with one edgeand resting on this lip, and the far side resting on a lip on cabinets (still to be built) on the other side of the van.

Structure of the bench largely complete

Cladding

Once the bench was complete, we spent many hours figuring out how the cladding could work. The van walls are curved, and flexible plywood could conform to the curve, but there are very few places where it could be pinned back to the walls, risking it flapping around, unsupported, or ‘drumming’ when on the move. So we decided to build a flat frame for the middle section of the wall, onto which one large sheet of flat ply can be fastened.

To clad that section, we re-used some of the 5mm plywood that was in the van when we bought it , cutting out holes for the task lights and USB sockets. It feels pretty solid, so we’ll see how it works on our trip in a couple of weeks.

One wall section insulated, with electrical supply, and framing up ready for cladding

2017-07-09: Fitting roof light and fan

We fitted the fan and the roof light this weekend. Each job took a whole afternoon.

I started with with the Maxxfan. I didn’t take many photos because the whole job was a bit stressy and I wasn’t sure it was going to work. I needed to concentrate.

The Maxxfan is great – we were pleased with it straight out of the box. The plastic is not flimsy, installation is well thought out and it looks good. It is designed so that you can fix a retaining ‘flange’ to the roof and then the machine itself screws onto the flange later. This means you can easily remove the machine for repair without having to phaff about with the bit that holds it onto the roof. Likewise, the decorative bit inside that hides wires etc gets screwed in place independently.

This is a bonus for us because we don’t yet know what we are going to clad the van with, and how thick the roof will be. So we can still drive about with the fan fixed in and worry about trim later.

Caravan bits are designed for flat roofs. The sprinter doesn’t have a flat roof in any direction – it has bobbly bits which can’t be avoided.

I started by trying to draw the 40cm square  for both the roof light and the fan on the ceiling of the van where we wanted the holes to be.

This was very difficult, (rulers too long/ short/ bendy, neck and arms hurting, right angles never matched up).

marking the roof light square inside the van

I got fed up in the end and using a punch, made some discrete mini dents (one at each corner) then got up on the roof and using the dents as a guide measured the 40cm square again (much easier on the roof).

Here’s the square for the fan:

The square marked out for the fan (close to the back of the van)

 

And here is square for the roof light

The 40cm square for the roof light, near the front of the van

Then I cut out some squares of some plastic stuff we had hanging about at home that we found on a skip. (Andrew know what it’s actually called – Andrew: it’s called expanded PVC). it’s bendy, about 6mm thick and can be carved easily with a Stanley knife. The squares matched the flange for the roof light  (variable widths) and the fan  (same width all the way around) and also had a 40cm square hole cut in the middle.

The plastic insert for the roof light

Next I carved bits out of the plastic insert to correspond to the bumps on the roof. Each cut is at about a 45 degree angle or more to accommodate the roof shape at best as possible.

Then I sanded the plastic and cleaned it with degreaser.

The following photos and account are mainly the roof light, but I’ve slipped in a couple of photos from the fan where I didn’t have the equivalent roof light photo.

We were pretty disappointed with the roof light when it arrived. It was advertised as white but is in fact more magnolia coloured. It feels flimsy, and the installation needs you to have determined the thickness of your roof.

The roof light. (No forced ventilation so it doesn’t whistle when we drive)

I sellotaped a bin liner inside the van to catch the worst of the metal filings, and a bit of cardboard on the roof to try and stop them getting under the solar panels.

The bin liner sellotaped inside the van to catch metal filings (fan)

Then the noisy bit!

Up on the roof again, I drilled a hole in each corner  (10mm bit) for the jigsaw bit to start in. Then I cut the four lines.

To minimise vibration I put duck tape across each cut I had made when I finished that side of the square. It also stopped the cut out falling into the van.

I didn’t bother with masking tape on the plate of the jigsaw because everything is going to be covered with sealant. We have a cheap  £40 jigsaw from Machine Mart and it did the job fine. Going over the bumps was noisy, wobbly and a bit tricky, but I found if I kept the front of the base plate pressed down where possible while keeping it level, it didn’t matter too much that the back end was in the air and the blade coped ok.

Hole cut for the roof light

The bit of cardboard didn’t work – the filings got everywhere. So after filing down the edges I hoovered the whole roof and everywhere else and removed the bin liner carefully.

I sanded the edges and a little way around the opening, cleaned with degreaser,  painted Hammerite primer on the bare metal edges and had a cup of tea.

Then I stuck butyl tape (see in the picture above) around the opening to seal the plastic insert to the roof.

Butyl tape stuck around the hole for the roof light

The tape was 20mm wide so in some places I used two strips. You can cut it with a Stanley knife. It’s like chewing gum.

Then I put the plastic insert on the top of the tape:

My plastic insert on top of the butyl tape.

I used Sikaflex Caravan Sealant 512 (also pictured in earlier photo) to seal all the way round and fill any gaps between the insert and the bumps on the roof.

This sealant sets (stops being sticky) but stays rubbery. I think the butyl tape doesn’t set (the bag it came in was not airtight at all). Ordinary bathroom silicone sealant which I intended to use originally dissolves the butyl tape and turns it into a slimy mess (lucky I tested it first).

Now the insert was in place I wanted to get everything tightened up together before the sealant set.

In the case of the fan, I put a continuous square of butyl tape on top of the plastic insert and the provided roof insert is then screwed (using about 20 screws) through the metal of the van roof. We also cut four bars of wood and clamped them inside the van so that the screws went into wood after they had gone through the roof (the sandwich of materials went like this from top to bottom: maxxfan plastic roof insert, butyl tape, my homemade plastic insert, butyl tape, roof metal, wood) Then I sealed all around the edges and over the screw heads in a big smeary mess.

The fan in place and fixed to the plastic flange insert that has been screwed to the roof  – you can just see the screws.

The bits of wood that we used inside the van were a last minute decision when we realised how the screws just poked randomly through the roof.  They aren’t totally necessary. In retrospect it would be better to make something neater and smaller in advance (like we did for the roof light).

In this picture the fan has already been lowered into the plastic fixing flange in the roof hole.

The roof light was slightly different. Since repairing or replacing the roof light involves removing the entire thing- the seal needs to be less permanent.

I applied a thick bead of Sika Lastomer 710 as per instructions to the underside of the roof light. and eased it into the hole. This stuff stays flexible and sticky, like the butyl tape.

This picture shows the underside:

Underside of roof light

It is supposed to have a clearance of 2-3mm all the way round. (my hole was a titchy bit tight but its almost impossible to re-jigsaw a cut and filing more than 1mm off a cut edge isn’t feasible either, so i’ll just have to hope its OK).

I used about half the tube of Sikaflex and it bulged out nicely from under the plastic so I know I got a good seal, but it was a bit messy clearing the excess away.

Roof light sealed into place

Off the roof and into the van now.

Here is the bit that fits inside the van:

Roof light plastic insert fits inside the van.

Andrew had earlier made a 40cm square out of 12mm plywood, 50mm deep and held together with small metal brackets at the corners: you can see it in the video at the end but I forgot to photograph it.

This filled the gap inside the van between the bit of the roof light that sticks through the hole you’ve cut and the bit of plastic inside the van (way more complicated and fiddly than the maxxfan). You are supposed to measure the gap between the inside of the roof and the cladding of your van to calculate how much to chop off the plastic bit inside the van.

We haven’t insulated or cladded the van yet so we had no idea about this. The maximum depth the plastic can extend to without leaving a gap is 60mm anyway and since our celotex insulation is 50mm, Andrew thought the wooden frame should be 50mm deep. Turns out that this was a perfect guess.

The plastic bit that fits inside the van and is supposed to slot inside the plastic square poking down through the hole. The screws marry up and their plastic surrounds butt up against each other. This is what braces the inside part and outside part and holds the roof light in place.

Yep- we thought it was all rather flimsy too. So the wooden frame is to prevent too much compression.

Roof light stuck onto roof and inner plastic flange screwed into place from inside the van to pull it down onto the roof and tighten the seal. Wooden frame sandwiched between the two parts.

Later you clip the rather hideous peachy plastic trim to the plastic bit I’ve just screwed into place. Won’t be doing that till we’ve cladded the van inside.

Decorative trim that goes inside. Nasty mottled beige blackout blind and a useful fly screen.

Next I went back onto the roof and attempted to clear up the bulgy bits of sealant. Not very successfully – it looked rather a mess.

This bit wasn’t too bad. You can just see the plastic insert I made.
This was the worst bit – where I tried to clear excess Sika Lastomer, I disturbed the not quite set Sikaflex sealant I had applied around my plastic insert

Here are the tools I needed for the job.

Ladder, Towel, Jigsaw with metal blade, Drill and 10mm drill bit for metal,  extension cable, hoover, ear muffs, googles, Hammerite paint and small brush, metal file, Sharpie, ruler, set square, tape measure, pencil, punch and hammer, duck tape, masking tape, large bin liner, paper towel, degreaser (strong detergent), sandpaper, butyl tape (20mm X  9 metres was plenty) SikaLastomer 710, Sika Caraven sealant 512, caulking gun, screw drivers, a few bits of wood and angle brackets and a couple of large clamps, a sheet of 6mm plastic, Stanley knife.

Tools for cutting the hole in the roof

Here is the Plastic insert I made, Sikaflex caravan sealant 512, Sika Lastomer 710,

The plastic insert I made, Sikaflex, SikaLastomer and butyl tape.

Here’s the video:

 

 

 

 

2017-07-02: Starting the electrical install

This weekend, we started running cables and mounting components so we can get the electrical systems hooked up. We already have the solar panels on the roof, and the battery fitted under the passenger seat. We also have a fair amount of conduit routed through the side panels of the van so we can run cable from front to back (e.g. from the fusebox to the ceiling lights or rearmost USB sockets).

Green lights are always a good sign. We are now successfully charging our battery from our solar panels. Very exciting.

Nothing at this stage is fixed, but we need to commit to some decisions so we can continue the build. So it’s a delicate balancing act of deciding where things should go, while leaving options for us to change our minds. In practical terms, that means:

  • Making prototype mounting boards and boxes for components roughly out of MDF to test out placement and design before rebuilding them properly in nicer plywood.
  • Making some educated guesses about where we want wires to emerge, and cutting cables to length.
  • Wherever possible running wires – cut to a generous length – through conduit so we have some flexibility in exactly how we place the end components (lights, sockets, appliances, etc.).

Our electrical system starts in the area immediately behind the cab. It’s something of a no-mans land that in many conversions would just be wasted space. We’re hoping this will be a space-efficient placement. The main elements are:

  • Leisure battery in the passenger bench seat base (with space for a second battery in the other half of this seat base if we need to expand)
  • Solar controller on a board mounted to back of passenger seat base (with space for some other components we might add later, such as a battery-to-battery changer, inverter, or mains power charger)
  • 12V fusebox and distribution mounted to back of driver’s seat base.

By separating the ‘power in’  (solar, alternator, shore/hookup power) and ‘power out’ (12V circuits) into 2 areas, we have more space to mount components without intruding into the main living space of the van.


Meanwhile, the insulation installation continues, as we desperately try to clear our house of bulky building materials.

We’re getting through cans of expanding foam at an alarming rate.

2017-06-25: Solar panels

 

Another big job done this weekend, and one we faced with some trepidation – installing the solar panels. While they’re not yet wired up, they are now mounted on the roof. It’s a very tight fit up there, as we want to fit 2 large panels (1m x 1.3m) as well as a roof light and fan.

Cleaning and polishing the roof. Our last chance before we cover it with solar panels.

We had measured the available space, and checked for obstructions both inside and outside, but until you start the job, there are no guaranteees. Sure enough, we soon discovered our first brackets supplied with the panels didn’t  quite fit between the raised ledges that run down the edge of the roof. So we had to mount the brackets on the inside of the aluminium frame of each panel. Mounting to the panel was easy, but when it came to mounting them to the roof, the brackets were underneath the panels.
This was the easy bit, before we had to deal with misaligned holes and bolts in hard-to-reach places
 

Aluminium angle brackets mounted underneath the panels. The only way to fit them on our roof
Fabricating some spreader plates to go on the inside of the roof skin, to spread the load in case of an upward force in the panels
Spreader plates. The clear goo is the CT1 adhesive

So we had to lay the panels where we intended to place them, mark all the holes with a pencil, move the panels aside, drill holes and then hope they all lined up. 

As well as M6 bolts (2 per bracket, 4 brackets per panel) fastened with locknuts, we also glued each bracket down with CT1 adhesive and fabricated some aluminium spreader plates to spread the load on the inside of the roof. 

We also made some progress buying materials we need to fit the rooflight and fan, installing more insulation, and treating more rust we found on the roof.