A Brit builds a cedar stripped teardrop

[MikeG2]

Zero idea, but grossly cool.

Yes, it is (the album, I mean). Dark Side of the Moon, by Pink Floyd.

 

[Tony Latham]

Dark Side of the Moon, by Pink Floyd.

Extra-extra cool.

T

 

[MikeG2]

I'll give this another go. If I end up talking to myself, I'll just stop.

-

We'd got to the point where I offered the sides into place for the first time.

I knew as soon as I lowered them onto the floor that we had a problem:

The frame isn't straight. The back end is 22mm down. I can't work with that, so the guy who made it is coming up to have a look, and will probably have to put it in a press. So, there'll be another hiatus.

Those of you following along closely will note that the frames/ walls don't sit ON the chassis. They sit outside the chassis, covering it, with the weight being born on a "shelf", which forms part of the floor structure.

I called the fabricator and told him of the problem. I then went off for a few days on a 400 mile bike ride around Norfolk, and whilst I was away he came up to my house and straightened the chassis. He did it fairly well, but not perfectly. I asked him to come back, but was wrapped up re-rendering the house and so was unable to photograph the process. It involved a big RSJ, some clamps, some spacers, and a bottle jack, and they did a decent job. When I could grab a moment, I could then start putting everything together.

One of the issues I have mulled over in the early hours when trying to sleep, is that there is no reference locating the frames on the chassis, and in relation to each other. Here's the front and back of the frame when it's roughly in the correct location, to show you what I mean. They just don't align with anything:

That's front and back respectively.


Whilst I am sure I could get over small discrepancies, obviously it would be easier if things were parallel, square, and symmetrical. I came to the decision that the bulkhead between the sleeping area and the kitchen would be the best way to control everything, because so long as it was right angles to both sides then I would know where everything was correctly in relation to everything else. So, I set about making that bulkhead. I started with 6mm ply, and noted immediately that it was out of square:

I trued that up, and then used a pair of pinch sticks to get the exact distance between the walls and transfer it to the ply:

 

[MikeG2]

When I cut the ply out, I also cut a batten to the exact same length, marked it up loudly, and will use that for reference later. The ply had to be shaped around some bits and pieces (note the pattern), but once dry fitted I could immediately square up the walls:

I spent a long time measuring and checking square, to make sure everything was absolutely spot on. I made a 3:4:5 square especially for the purpose.

I quickly realised that the ply was too bendy to be reliable for the task of positioning the frames accurately, so decided to add the framing to it to stiffen it up. In another departure from the normal the insulated envelope of the teardrop doesn't follow the line of the outside. There is little point insulating the galley area, and there is good reason to insulate between the galley and the sleeping area (particularly for noise from the fridge, but also to keep the warmth generated by the fridge out of the bedroom)........so the bulkhead in question is insulated, hence the framing.

At this point I realised that one of the sides of the straightened chassis wasn't straight enough. Here's the gap with a wedge in it:

That's getting on for 4mm. OK, that's a damn sight better than the 22mm we started with, but too thick to deal with just with the sealant. As it was the weekend and I had no choice, I decided to have a go at it myself. I laid a big piece of green oak on some packers, and with 3 clamps I squeezed the frame up to the oak:

About 25mm of bending produced a result, but an immeasurably small one. I tried again, with bigger packers, and had to use a spanner on the clamps to get enough pressure on them:

Eventually, I achieved a dramatic improvement:

However, that created a bend elsewhere, so I spent some while chasing smaller and smaller bends along the frame using the same technique:

That took a couple of hours of stuffing about, but I got everything to within coo-ee of straight. It cost me a G clamp, which failed impressively under load.

 

[MikeG2]

After that, I made final preparations for fixing the frames permanently. Little things like allowing for welds:

........by chamfering part of the frame away:

Having stiffened up the bulkhead with the frame, I was able to do a final dry fit of the side walls to their exact locations. I clamped them in place, and set about marking for the bolt holes which would locate and secure them. I sharpened up a short piece of threaded rod, pushed it through the holes in the frame, and tapped it with a hammer to produce a centre mark:

I had to do that because I couldn't get a drill near a few of the holes from the underside of the trailer. There's just stuff in the way. I could then use the centre mark to drill a pilot hole, then a recess for the head of the carriage bolts, and finally the 9mm bolt holes:

I gunked everything up carefully:

I am specifically using this adhesive because it is low modulous, (flexible), watertight, gap-filling, sticky as ****, and it lasts forever. If there is going to be any movement, it will be between the bodywork and the chassis, so a flexible adhesive seems sensible. Anyway, the first side was soon in place:

Next came the bulkhead:

Naturally, I forgot to take a photo of the second side in place. You'll just have to take my word for it. Everything was then secured with M8 stainless steel bolts, albeit with temporary mild steel nuts. I found the box of stainless Nyloc nuts as soon as I had finished tightening the last temporary one. Ho hum.

On to the floor. I did lots of sawing, chiselling, marking and measuring, and eventually had the floor frame ready for fitting:

I've said it before, and I'll say it again: there'll be no butt joints on this job. They're just not robust enough.

 

[MikeG2]

This was a particularly awkward joint to chop out in situ:

Nonetheless, it all went together OK, and was bedded down in the same black gunk as holds the frame down:

All glued and pinned, and finally clamped down ( I don't want anything squeaking!!):

Once the insulation and ply are in place, then coach bolts will squeeze the whole lot down to the chassis.

Here's a general view of the scene:

 

[KCStudly]

Just finished going through your build thread and am enjoying it immensely! The organic form of your interior cabinet and shelf face frames is inspirational art and craftsmanship. If you have more pics and care to delve into that aspect of your build I, and I'm sure others, would surely appreciate it.

I, too, felt compelled to straighten my home built trailer frame after welding. Got it pretty close, too, using similar hydraulic methods. One of my side walls had a little wing up at the base where the laminated galley wall end cap had some stresses built in, so, after making the upper portion if the wall match my template, I glued an oversized wedge/shim under that end of the wall and worked the excess back to flat and true.

Please keep posting. I did that a lot when I was more active, and I found that it helped in many ways. Helped me review and organize my work process and quality (sometimes I, or others, would see things in the photos that I didn't see in person at the end of a long day). Having people offer suggestions in real time was useful on more occasions than I can count. Don't worry if you don't get a bunch of comments at first, you're doing a great job, both in building and documenting, that people will comment, share and cross reference.

 

[Tony Latham]

Any rough guess on what the green oak timber weighs?

Tony

 

[MikeG2]

Any rough guess on what the green oak timber weighs?

Tony

Probably only around 100kg. I've made stuff for this house out of oak pieces weighing nearly 500 kg (half a ton).

 

[MikeG2]

......The organic form of your interior cabinet and shelf face frames is inspirational art and craftsmanship. If you have more pics and care to delve into that aspect of your build I, and I'm sure others, would surely appreciate it.....

I'll get to that in due course. It was something I really enjoyed doing, and there are quite a few photos of the process.

 

[MikeG2]

The floor is insulated as per all the other outside surfaces. Here is the 25mm Celotex held down well against the expansion of the PU glue holding it in place:

After de-clamping, and filling the gaps with foam:

I have something of a confession to make. I waste an inordinate amount of time in every single project I do trying to work out which piece of stock to use for which particular part. The first bit of floor here was easy:

..........but the two silly little bits either side of the well held me up for hours. I ended up drawing all of the remaining bits I needed and all of the remaining stock of 1/2" ply I had, and after printing it, cut everything out so that there could be no more (internal) conversation on the matter. I drive myself absolutely nuts with this behaviour. Nonetheless, this time there was a way I could have cut things out which would have meant running out of ply, so I guess it was somewhat justified.

In the meantime, whilst distracted, I took delivery of a pair of brackets which will support the forward end of the corner steadies (jacks). Remember the little brackets I cut off a while back?:

Drilling the appropriate holes for riveting them in place cost me two 3.5mm drill bits. After a deal of frustration trying to drill the holes with the brackets loose, I eventually decided to adhere the brackets in place, and then drill the holes once everything had gone off. The approach worked, but it was a tedious and frustrating job:

The above photo shows the brackets propped in place whilst the Hippo 3 set overnight. At the same time, I glued the Celotex into the bulkhead that separates the sleeping area from the kitchen. This is a change from the normal practice with teardrops, but I want to entirely isolate the sleeping area:

Eventually, I was confident enough with my cutting decisions that I was able to complete the fixed part of the floor. You can actually see one of my drawings for what-is-cut-from-where in the following photo:

The next major task was the well. This hangs below the floor of the trailer, and so is designed to be made of phenolic ply. It's going to get wet and muddy, no doubt. The thing is, I was determined to make all the joins of the box with dovetails. I wonder whether the material has ever been dovetailed before!!

It was a bit of a pig. Obviously, it's impossible to use a chisel. That didn't leave me much choice but to use a rasp. It's many a long year since I made dovetails with a rasp. I didn't mind sawing the stuff, because obviously a saw can be re-sharpened:

Rasping without breaking out the far edge is a bit of a discipline. I rasped down to the line on both slides.........but on a slope:

 

[MikeG2]

This left a mound in the middle, which then got filed flat:

You also couldn't do trial fits, for fear of breaking off layers when dismantling if any part was a little too tight. To be fair, this is my approach in proper wood too. I'd barely offer the parts together just to check I hadn't made a major cock-up:

Instead of gluing with PU, I had long decided to use Hippo 3, as I imagined this box might be subject to some flexing. PU is a bit brittle, but Hippo 3 is flexible:

It took literally days to make a single box. Please, for your own sanity, don't rush to dovetail phenolic ply, and don't rush to use a rasp instead of a chisel for ordinary dovetails! Eventually, though, it was finished:

Whilst that was curing I made the frame for the removable hatch over the well. This has to be pretty strong as it is under our hips as we sleep. This probably doesn't need explanation:

 

[MikeG2]

Here's the completed frame of the well cover:

By now the Hippo 3 had dried in the well box, so I slapped some waterproofing Black Jack on the joints:

I'll be bedding some angle over those joints later. When that dried, I offered it up in place:

It didn't fit because of some welds in the corners of the chassis opening. That meant rounding over the corners with a belt sander:

.....and then re-Black-Jacking. Look how well those dovetails worked out!!

I offered it in place again, but prevented it from going down more than an inch or two, as I realised it would be virtually impossible to get it back out again. I was only slightly confident it would fit, but nonetheless, gunked up all of the steel with Hippo 3, and dropped it in place:

Yay!!

There were some funny little gaps between the box and the support straps:

I loaded up the box with half a dozen 2" paving slabs:

And then wedged the straps up tight to the underside of the box.

I test fitted the well hatch:

That was actually out of order, as I test fitted that prior to fitting the well box.........otherwise the astute of you would have worked out that removing the lid would be a **** of a task. Anyway, all was well.

The next frame was the horizontal element of the bulkhead:

 

[MikeG2]

That's very carefully glued and screwed. One of the purposes of this bulkhead is to isolate the sleeping area from the kitchen both for smells, and for potential gas leaks, so there was lots of PU glue everywhere to make sure that there was no air path through anywhere. I then insulated it:

Next, I completed the bulkhead by applying the top sheet of ply to the shelf element, and then framing up the remaining vertical piece, gluing and screwing it in place, then insulating and ply-ing it:

I then glued on the remaining face of 6mm ply:

 

[MikeG2]

On to the roof!!!

I started by using a spline (an offcut from the endless piles of Douglas fir I ripped up months ago) to mark out the key positions of the profile, like where curves started and stopped, and where the bulkhead was located, so that I could plan the ply join locations for the roof. What I really wanted to avoid was joints between sheets on the tightest curve. So, here's the spline:

I then took this to a scaffold board, just because it was convenient, and played with it a bit until I was happy:

I realised that I would lose easy access to the sleeping area when the roof went up, which could make bolting the floor down a more awkward job.......so I spent a while under the trailer drilling up through all the various holes. Some of them were too close to the chassis to allow use of a cordless, so I ended up using a brace. I also gunked up around the well whilst I was under there:

I also realised it would be easier to do the roof if I could stand inside, so I needed the well lid in place. To that end, I fixed on some nylon strap handles. They'll do until I think of something better:

Back to the roof.....

From 6mm ply of the walls and bulkhead, all the action now involves 3mm ply. I clamped 3 sheets together and cut them all to the same length. This is one of those moments where you check the measurement and marking out obsessively, 3 or 4 times. Once you get this far you are committed:

If there was any one moment in the build of this teardrop that I have thought about over and over, and perhaps worried about a little, it was bending the roof over the tight curve. I hadn't bought expensive bendy ply......just normal 3mm poplar ply........so trying it around the bend was quite tense.

Phew!! It didn't even creak.

 

[MikeG2]

I cut a few of the roof timbers to length, drilled a screw hole at each end sinking the head some 25 or 30mm, and began the glue-up of the first couple of bits of ply. I had 2 roof timbers which were wider than the normal 25mm, to deal with joins between the ply sheets:

I glued and pinned, and fixed the first roof timbers....by braille. It went well.

That feels like quite a moment. I even got to lie inside it for the first time. It felt very roomy.

 

[TD Gnome]

Awesome job! This is past construction into art, you sir have mad woodworking skilz!

 

[groys02]

My first time seeing your build thread. Very impressive!

 

[MikeG2]

The roof timbers on the tightest part of the curved roof needed (I felt) a little relief in the middle to help them sit flat. I roughed out (and I mean ROUGH) a shallow groove up the middle so that they had 2 points of registration rather than one:

A couple of the "joists" (spars?) were a little difficult to mark on the inside to give me a clue as to where to fire the nails. Turns out, if you park it under the light, there is no issue:

We ran out of shavings for lighting our fire, so I needed a quick planing project. The bottom roof timber, where it meets the floor and the frame, provided an ideal candidate, so I bent one of the Cedar finishing strips into place and held it however I could:

......and used it to mark up the pair of timbers at the bottom front edge of the roof:

Then started planing:

A quick glue-up ensued:

 

[MikeG2]

At this point, I took a couple of months out to work on the house.

My focus then moved to the galley (kitchen). The galley floor isn't a simple thing, because I had decided on a fairly substantial, but shallow, storage area below the floor proper. This was to throw up some awkward details and junctions. I started with my last pieces of phenolic ply, and made a very simple box/ tray:

The big deal with this detail is the presence of the "corner steadies" (jacks). The storage had to allow them to work unimpeded. Here's a dry fit (before and after):

That allowed me to accurately measure the depths, and make a central divider:

Its walls, and particularly the central divider, act as support for the proper floor. So, the next task was to cut out the floor itself from some 12mm ply, and create two access hatches:

Those hatches aren't the same size. By making one bigger than the other, I was able to take the off-cut from the bigger hatch and trim it to act as the hatch for the smaller hole. I didn't order much spare ply, so can't afford unnecessary wastage. Here it is dry-fitted in situ:

I glued some strips along the long edges and left them clamped overnight. These will support the lids:

Here's the "after" photo:

I did a quick check of the fitting of the fridge, which determines the rest of the kitchen layout: