Building an ultra ultra lightweight <span class="highlight">caravan</span>. Tips welcome

Submitted: Thursday, Nov 12, 2015 at 00:34

ThreadID: 130865 Views:6178 Replies:11 FollowUps:19

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eaglefree

Some time ago I revealed here we purchased a Detour camper trailer to be towed by our VW style Subaru powered Panther trike. Well we did that, made some modification to make life better (toilet on the drawbar etc) but after 18 months and some medical restriction we are selling our camper and embarking upon building our own caravan.
Vw style trike have a problem, that being their towing GVM weight cannot go over 250 kgms or 300 kgm with brakes. The reason is simple, the front wheel wants to rise off the ground. I've towed a GUPPY caravan for a short time with ease at 600 kgms loaded but as I'm now retired I want to stick to the trikes safe abilities.

250 kgms isn't much eh. So I decided to not have brakes on the van. For the last month my wife and I have been designing and ordering parts, steel etc. You name it. The van internal design results in the external dimensions. We settled for two single beds with a narrow aisle between, a small kitchenette and the surprise...a shower and porta potti.

So far we have purchased the solid axle (21 kgms with hubs), two 10" alloy wheels (8 kgms each) and two trailer springs (12 kgms) total 49 kgms. The middle section of the axle could be replaced with tube to lose 10 kgms but not at this early stage. Reason being, 250kgms loaded and hoping for 199kgms or less tare weight means the van will be vulnerable to side winds. Low centre of gravity is essential as is minimal height of the van itself.

A note about the suspension. I desired torsion suspension but went away from the idea. Most are designed for 13" wheels or larger diameter. I weighed a 14" wheel from my Hyundai car and it weighed 18 kgms- 10 kgms more than my alloy 10". So the extra expense wasn't justified.

I've chosen steel as my frame material...why? because I can weld steel lol. Also it "gives" with flex and wont crack like aluminium. Again being retired cost is a big issue. So I've ordered my steel. I had to hunt around for 13x13x1,6mm square tube which weighs only 500 grams per metre. Drawbar is 50x25x2.5mm with 10mm rod strengthener under it. Floor...6mm marine ply. Sounds thin eh. But the 13x13 tube under it will be no more than 160mm apart. I just couldn't spare the weight factor of 9mm or 12mm ply. 2 sheets of 12mm ply could weigh 40 or more kgms. The ply has been prepared. The underside has had 2 coats of acrylic outdoor paint, two coats of waterproof paint and a further 2 coats of outdoor paint.

There will be a built in "rollbar". But it isn't a rollbar just a bar more solid than the rest of the frame. I'm experienced in building "cage" type framework so relevant crossbracing will be done so the strength will also come from the cage final assembly.

200 kgms tare is a real challenge. However there has been some surprises. The acrylic shower tray weighed only 1.6 kgms with a porta potti section. The acrylic sink and basin was 1.5 kgms and is 700mmx310mm size. Windows- Odyssey windows weigh a couple of kgms each, we'll have 3. Our single vent with 12V fan incorporated weighs little. Water- We settled for a 43 litre 800mm long 220mm square unit. I know what you're thinking. Lots of weight. But we don't have to fill it up. But we can if stationary for some time.
We decided on a 12V pump for the camp shower and kitchen sink. A 25mm tap natural drainage from the tank will be used to fill buckets needed for the submersible camp pump. A 20 litre hot water camping bag will be used for hot water, add it to cold water in a bucket, place bucket on porta potti and have a nice shower.
Access hatches. 3 will be purchased of the type we use our own sheeting to complete. Two for under the bed storage and one large square one for ease of porta potti access to empty it. Aluminium hatches ones are heavy.Again we don't want to bust our backs lifting it in and out of the van. Off cuts of exterior wall sheeting will be sort and new roof cladding.
Rear door access. Doors are heavy. Eventually we found a door off a pop top van that weighs 8 kgms. Its 630mm wide but only 1427 high meaning a bit of a head dip as we enter the van. Cost $50. We had to drive to Canberra from Euroa to collect it lol. but worth it. Pine will be used a lot inside the van for bed frames etc. Clothes will be hung in clothes hangers, the type made with material and hung from the ceiling. Lightweight auto carpet weighs little for the ceiling and walls 3mm veneer board. We are on target to make the under 200 kgms limit.
Then we'll have only 50 kgms for- fridge (Weaco cf-17 weighs 17kgms plus food), water, bedding, clothes, lightweight plates, butane cooker, lightweight chairs, power from the trike at this stage. Again, all a challenge.

Hope I haven't given you all a sense that I know it all- I don't. Just that most of the decisions have already been made. But am open to ideas anyway. cheers Tony[img]

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Dimensions external 3275x1850x1900mm floor 1820x2765mm[img]

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Reply By: Member - Alastair D (NSW) - Thursday, Nov 12, 2015 at 07:15

Thursday, Nov 12, 2015 at 07:15

Interesting project. I am building an expedition vehicle based on an Isuzu NPS300 4wd truck which has a 6000kg GVM. My target is 5000kg all up loaded so I know about watching weight but on a different scale.

As well as the total gvm you also need to watch the weight distribution front rear & L/R. If you know how to use a spreadsheet then it is easy to map the weights using the axle and centre line as reference points. Getting the balance right at the correct ball weight will make a huge difference in the ride. With the right f/r balance the van will bounce up and down on the axle, if it is not then you will get pitching which I don't think would be nice on the trike.

Let me know if you want some help on how to do the above.

cheers & good luck

AnswerID: 592611

Reply By: wholehog - Thursday, Nov 12, 2015 at 08:03

Thursday, Nov 12, 2015 at 08:03

Yes, very interesting project. I ride a Goldwing, and anyone who tows with a motorbike has bigger balls than me, but my hat off to you for your ambition and tenacity. Good luck. :-)

AnswerID: 592612

Reply By: gbc - Thursday, Nov 12, 2015 at 08:45

Thursday, Nov 12, 2015 at 08:45

Ive got a 200 k.g. counterweight off the old 60 h.p. fergie out the back you can have for nothing. Bolt it to that front swingarm fork and you'll be able to tow a Kimberley Kamper!
Just kidding. Looking forward to the build, but yes, fulcrums and levers are not you friend in a rear engine trike. Can you put weight on that roofrack, or make it loadbearing?

AnswerID: 592613

Follow Up By: gbc - Thursday, Nov 12, 2015 at 08:53

Thursday, Nov 12, 2015 at 08:53

If it's all about the front wheel rising, an extra long drawbar will solve most of your problems so long as the trailer wheels are far enough back. This is how yanks tow 6 tonne + boats - really long drawbars.

FollowupID: 860804

Reply By: Rangiephil - Thursday, Nov 12, 2015 at 10:18

Thursday, Nov 12, 2015 at 10:18

IMHO you have to ask yourself if it is wise to tow 300Kg with a trike.

I must state my position that IMHO trikes are a waste of space as they are just about as wide as a car so no lane splitting, and are inherently unstable particularly when towing.

If you need the "wind in the hair" buy an older Suzuki Vitara convertible say 99 ( or Sierra) where you have the choice of roof on or off, and sunroof, and sealed, with probably comparable economy.

You would also have far more room for stuff and can go on unmade roads and even gnarly tracks.

A Vitara can tow about 1650Kg at 1.5 times tare or AFAIR about 600KG unbraked.
I and my family have owned 2 and it's amazing what you can fit in if you remove the rear seats or even just fold them down.

Regards Philip A

AnswerID: 592619

Reply By: eaglefree - Thursday, Nov 12, 2015 at 11:13

Thursday, Nov 12, 2015 at 11:13

A very important point Alistair. With the body of the van it is rear bias at the axle point. The fridge and water tank are just behind the axle. I reckon the drawbar alone will result in a slight front tip towards the coupling. L&R balance too has been thought of, thanks.

300kgms means about 20-30kgms towball weight. I could put 40kgms in my top box and handling isn't affected. The weight limits on trikes are mainly from the manufacturer to safeguard themselves. However if these weights are ignored and an accident occurred the trike insurer might well knock back a claim. Hence the desire to stick to the limits.

This thread isn't about whether I should or should own a trike and tow a caravan with it. Many people own trikes for medical reasons unable to ride bikes. I've had bikes, many of them, only trikers know why they ride them. It's about sharing my challenge and listening to others ideas.

I'm naïve when it comes to sealants and the edge trim of the cladding. I saw a van being repaired and the roof cladding was bent over then stapled to the wall wooden frame with lots of sealant. I assume I'll do the same and use blind rivets into the steel frame. But what sealant does the caravan industry use?

I'm planning to use 2.7mm ply (already ordered) for under the thin roof cladding. What sealant is used there? to glue the cladding to the ply? For weight reasons I don't want to use ply between the wall cladding and the steel frame. But I'll need to use something between them like a rubber or sealant to stop corrosion? The frame will be 13mm thick so polystyrene has to be used to fill it in. Tony

AnswerID: 592622

Follow Up By: gbc - Thursday, Nov 12, 2015 at 12:12

Thursday, Nov 12, 2015 at 12:12

http://aus.sika.com/en/solutions_products/02/02a024/02a024sa08/02a024sa08100/02a024sa08105.html

FollowupID: 860809

Follow Up By: gbc - Thursday, Nov 12, 2015 at 12:14

Thursday, Nov 12, 2015 at 12:14

http://aus.sika.com/en/solutions_products/01/01a008/01a008sa04.html

FollowupID: 860810

Reply By: swampy - Thursday, Nov 12, 2015 at 17:30

Thursday, Nov 12, 2015 at 17:30

hi
Use only Sikasil Industrial
for semi permanent ,light to medium strength bonding
black white and clear
Trim can be removed with this product
very flexible
neutral cure [non corrosive ]
Even comes with a picture of a caravan/motor home on the front
5-7$ at Bunnings order in
long reseal service time

The poly ureathane sealants are recommended for permanent install
The advantages are high bonding strength , can get away with no screws although clamping would be required upon assembly
Trim work is destroyed upon disassembly

I rang sika for advice 3mths ago for advice on resealing my camper trailer . Suggest u do this as u mentioned timber bonding also .The customer service is good . I rang as the descripition online is very similar between most of there products . This is when I was told about sika sil [new product to aust ]

I only used the sika sil Industrial alloy to alloy /plastic

The poly ureathane debris left behind after a trim is removed is tough to remove . You may damage the base surface . [that's what alloy trim is for ha ha ]

hope this helps
swampy

AnswerID: 592638

Follow Up By: eaglefree - Thursday, Nov 12, 2015 at 18:59

Thursday, Nov 12, 2015 at 18:59

certainly does help Swampy. Thankyou. I'll certainly give them a call close to assembly time.

FollowupID: 860820

Reply By: Peter_n_Margaret - Thursday, Nov 12, 2015 at 21:54

Thursday, Nov 12, 2015 at 21:54

Bit late, but my start point would be glass (or carbon/kevlar if you are really keen) monocoque body based on sandwich panels, maybe some pulltruded glass sections for the draw bar and suspension supports.... and advise from here....http://vanglass.homestead.com/
Water tanks etc would be part of the structure.
Trailing arm suspension supported by Kevlar leaf springs.. :)

Cheers,
Peter
OKA196 Motorhome

AnswerID: 592652

Follow Up By: eaglefree - Thursday, Nov 12, 2015 at 23:34

Thursday, Nov 12, 2015 at 23:34

Thanks Peter,

I suppose being retired as many of us are, cost is easily blown out. Its already going over budget with the materials I'm using.

Surprisingly even with a steel frame and leaf spring solid axle I'm on target. The breakdown is

axle, wheels, springs and hubs 49kgms
Frame I'm allowing 65kgms
Floor 24 kgms
windows 10 kgms
internal fit out 25 kgms
ply for roof 7 kgms
roof cladding and wall cladding 10 kgms

190kgms. plus sealant, lights wiring. and I think I'll do better than 65 kgms on the frame.

Thankyou all the same.

FollowupID: 860832

Follow Up By: Member - KeithB - Sunday, Nov 15, 2015 at 16:45

Sunday, Nov 15, 2015 at 16:45

Looks like you've got 41 Kg for roof, walls and floor. That weight would buy your 10 sq m of 15mm thick Polycore composite material, which is the same stuff that I am using on my camper. Very rigid and if glued with pultruded angle, is amazingly strong and you can lay into it with a hammer. I am using it even for my underfloor water tanks. You could use it for your fit out as well.
Keith

FollowupID: 860918

Reply By: Ron N - Friday, Nov 13, 2015 at 11:58

Friday, Nov 13, 2015 at 11:58

Eaglefree - It sounds like you have 99% of the project worked out. The caravan fore-and-aft balance is going to be crucial.
You need to ensure no possibility of "tail wag" at speed, so I'd recommend the axle be positioned 25-50 mm behind the centreline of the caravan to ensure stability.

You're not alone on the project - I drove Perth-Albany-Perth last Saturday, and passed a bloke going the opposite direction, with a trike towing a good-sized van-type trailer or caravan. It seemed to be pretty stable.

Cheers, Ron.

AnswerID: 592676

Follow Up By: eaglefree - Friday, Nov 13, 2015 at 14:19

Friday, Nov 13, 2015 at 14:19

Thankyou Ron, Yes I suppose its all worked out.

For those wanting a bit of reading-

My wife and I owned a "Outback Camper trailer" that weighed around 320 kgms plus load say 450 kgms- without brakes. We towed it to Tassy (via ferry of course). During the trip we visited a lighthouse near Coles Bay on the Eastern side of the island. The road was a slim bitumen road with rubble in the middle of it.
Trikes for many years have had all three wheels operating on the same brake foot lever. Gone are the days of a separate hand operation for the front brake.
On the way down I wasn't travelling very fast say 35kph and being steep started to increase speed. I braked. Suddenly the front brake locked up on the rubble, the rig started to severely fishtail. I was counter steering in a desperate but futile attempt to straighten the rig. This continued for about 50 metres all the while dabbing the brakes on and off.
Towards the end of this dramatic experience and with my wife hysterical, there was a "T" intersection straight ahead with a dirt wall about 3 metres high, the road went to the right and a car park is on the left. The swinging fishtail action allowed me to swing into the car park. Lucky. Reckon we were doing 60kph or more at the end.
Also lucky that these trikes don't roll over being 180cm wide, like a F1 racer they just don't roll. It paid for me to know the trikes abilities.
I've learned a lot about trikes in my 7 years of ownership. Any more weight than say 350 kgms GVM and you need brakes. In my trikes case there is now more weight on the front wheel than when new without the roof. Downforce from 55 kgms to now 75 kgms.
There are many trikes that tow teardrop campers/caravans. I haven't seen a retail teardrop less than 280 kgms tare, most are 350-450 kgms plus load. They are asking for trouble IMO.
All this amounts to, in this build scenario a need for that best balance of the van. I thought it better to have the axle half way, right in the centre of the van with heavy items like the tank and fridge nearest the axle. But you have a point, 50mm to the aft would ensure a no rear bias of weight.

I'm also concerned about wind, even when set up camping. I'll mount two folding rings to the top of the van so I can clamp the van to the ground. See, it isn't common to own a van weighing 250 kgms loaded. I have visions of it being like one of those flying jumping castles for kids.

Here is our ChevronRV "Guppy" van we owned a couple of years ago. It was great but weighed too much with fibreglass roof and door. My worry is that insurance wont cover if an accident occurred. The first thing an insurance company will do is ring the manufacturer and he'll say "250kgms without brakes, 300 kgms with brakes". Hence the popularity of the smaller motorcycle camper trailers for trikes.

Here is a sketch of our proposed van.

FollowupID: 860849

Reply By: swampy - Friday, Nov 13, 2015 at 16:42

Friday, Nov 13, 2015 at 16:42

hi ,
Interested in the wheels hubs bearings u will be using ?
The smaller auto trailer wheels 8and 9 inch are speed limited and very very light duty poor quality to boot .
10 or 12 inch wheels ?? leyland mini wheels
There are 6/7/8 [cannot remember which size it is ] inch electric brakes suitable for small wheels . From the article I read these are order in to aust only .
luv the idea and your van that u sold very novel .

swampy

AnswerID: 592690

Follow Up By: eaglefree - Friday, Nov 13, 2015 at 22:55

Friday, Nov 13, 2015 at 22:55

Swampy,

This pic is of the 10" wheels and tyres. The axle, springs and wheels I bought from a trailer parts retailer.

This is a pic of the lightweight sink. under 2 kgms. will built a pine frame around it Under the sink will be light plastic drawers my wife has ordered.

These are the guards. Relatively lightweight saves making them from gal sheets.

This is the Detour motorcycle camper we are selling. Potential buyer coming tomorrow.

The next two pics are examples of my handy work over the years. The train loco was built over a ride on mower. 1995

So hope I'm up to building this van to a reasonable standard. Tony

FollowupID: 860873

Follow Up By: swampy - Saturday, Nov 14, 2015 at 11:54

Saturday, Nov 14, 2015 at 11:54

HI
The automotive trailer 10 inch wheel and tire combo . Is the load capacity and speed capacity up to what u need for the project ??? [also the wheel bearing capacity ]
After building some very very low trailers with the smallest wheels possible I found the load and speed capacity fell off greatly under 13 inch . Even 13 inch is not perfect [high wearing tires ]
That's why I suggested leyland mini wheel tire combo .Its seems to be the most common quality setup under 13 inch .

Yes it was 7 inch electric brakes commonly available .

swampy

FollowupID: 860883

Follow Up By: eaglefree - Saturday, Nov 14, 2015 at 14:53

Saturday, Nov 14, 2015 at 14:53

Hi Swampy,

The wheels are 10x3.5" maximum wheel load per wheel is 550 kgms. The van will never see more than 400kgms total (2 wheels) in its life.

The tyres are Deestone 8 ply tubed highway high speed (whatever high speed is tried searching couldn't find actual speed in kph) 5.00-10 maximum load per tyre 437 kgms.

So reckon I'm safe with a 200 kgms van tare and say 150 kgms load if I towed it with my Hyundai car and 50 kgms load if towing with the trike.

Glad you mentioned it. These figures never crossed my mind.

FollowupID: 860885

Follow Up By: swampy - Saturday, Nov 14, 2015 at 18:21

Saturday, Nov 14, 2015 at 18:21

hi
Many trailer but not all tires around this size have a limited highway speed 80kph . It would be in your interest to find out . [That's why I mentioned the "mini tire wheel combo"".]
Some top speed for some tires is only 40 km/hr or less . I have plenty of small machinery with smallish tires and was amazed at the differences out there.Another reason I only used 13 inch on the low trailers . Do a search on google to try and find specs .Deestone although ok would not be my first choice .Quite a lot of Carlisle and Kenda tires also come into the country .[there are others but my memory is not so good ] When u compare sizes between the brands nearly always deestone are wider taller smaller ,u get the idea .

swampy

FollowupID: 860888

Follow Up By: swampy - Saturday, Nov 14, 2015 at 19:04

Saturday, Nov 14, 2015 at 19:04

hi
145/70/12 mini stud
69 load rating 325kg / wheel
T speed 190 km/hr
500mm diameter

Be carefull of small tires as some make u pump the tire up to very high pressures to carry load
eg I have low profile 13 inch tires 90 psi for max load or 60 psi for normal use ,these are just to hard. Only use the last one for a spare now.

The 4.5 5 10 sounds ok but there are more common alternatives

cheers swampy

FollowupID: 860889

Follow Up By: Ron N - Sunday, Nov 15, 2015 at 01:15

Sunday, Nov 15, 2015 at 01:15

Eaglefree - Check the bearings, if any come with those axles/wheels. Usually, the bearings supplied in cheap, lightweight axles/wheels are Chinese no-name bearings, and I wouldn't trust them as far as I could kick them.
If they are Chinese no-name, replace them with some good name bearings, and you won't have a wheel suddenly depart from an axle, when you least expect it.

Cheers, Ron.

FollowupID: 860894

Follow Up By: eaglefree - Sunday, Nov 15, 2015 at 12:40

Sunday, Nov 15, 2015 at 12:40

These replies are exactly why I posted this thread. thankyou

I had ordered a spare set of bearings with my axle and wheels. So just walked out to the shed and looked at them. Cant determine if they are chinese or not but the stamp on the bearings say TAL and a part number.

Nothing comes up in google for TAL.

Tony

FollowupID: 860911

Follow Up By: Ron N - Sunday, Nov 15, 2015 at 13:16

Sunday, Nov 15, 2015 at 13:16

They are almost certainly Chinese no-name bearings. Buy a well-known brand name such as Timken, NTN, NSK, SKF,FAG or INA. Ensure that the box or seller states the country of manufacture.
All too often, mechanical failures today, can be traced back to Chinese components that have been manufactured to low standards or with little by way of QC.
Many Western manufacturers today have rushed headlong to utilise cheap Chinese components.
Where that manufacturer has invested large sums of money into Chinese factories and installed Western-style QC and supervision, then you can be assured of satisfactory quality. These components will be branded with a good brand name and come in a brand name box with the correct company logo and trademarks.
Merely requesting any Chinese-owned-and-run factory to supply critical components means that you are just getting a very large lucky dip, with quality, materials, and finish, varying enormously.
Surprisingly, I have regularly sourced top quality bearings off Amazon. The detail and specifications provided by sellers on Amazon is generally excellent, and you have a very wide choice of sellers, along with very reasonable pricing.

Cheers, Ron.

FollowupID: 860912

Follow Up By: Life Member - Terry 80FTE - Wednesday, Nov 18, 2015 at 23:17

Wednesday, Nov 18, 2015 at 23:17

Set up your spring and shackles on angle iron 8-12" longer than the springs, so as they will fit over the frame runners, then can be slid forward or backward of where you initially think they should be to get the best balance and on road performance, lightly bolt in place for trials, when happy, use a couple of heavier bolts and lock nuts per side or weld.
Cheers

Justify Your Existence
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Lifetime Member
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FollowupID: 861044

Reply By: The Bantam - Sunday, Nov 15, 2015 at 17:15

Sunday, Nov 15, 2015 at 17:15

Anybody interested in building light weight caravans would do well to look at the methods used in high performance sail boats.
Using epoxy, fibreglass and plywood incredible strength to weight ratios can be achieved.

Just slapping a sheet of 30GSM glass either side of a sheet of ply more than doubles its strength.

as far as flexing and vibration resistance ...... properly contrived composite construction will pretty much beat any other material available.

For this sort of work you would stay away from kevlar ...... because it fails to give sufficient advantage over glass unless you are realy pushing the edge of the weight barrier like you would in racing cars and top level racing boats.

If you are interested in reading about such things .... the two best recognised texts are " the Gudgeon Brothers on boat building" and "warram" on "fibreglass laminating".

Warram basicly covers standard bread and butter fibrglass laminating techniques ..... but is a bit narrow and adheres to fibreglass trade belief and convention.

The Gudgeon brothers, are the fathers of modern Fibreglass, epoxy and ply construction ....... between them they have either built or driven most of the world speed records for sail ....... one is an architect, one is a shipright and one is an accountant...... they work together in the family business ........ not only did they develop the mothods, but they developed the first well regarded modern marine epoxy ( the west system).

Their book is a heavy read bit it is an eye opener to what can be done with fairly simple and economical composites.

There is also a local marine architect ( Michale Storer ) who publishes small boat plans as a sideline, his website has quite a bit on the use of epoxy composites.

cheers

AnswerID: 592755

Follow Up By: Life Member - Terry 80FTE - Wednesday, Nov 18, 2015 at 23:08

Wednesday, Nov 18, 2015 at 23:08

Polycore composites honeycomb panel, lightweight and strong, different thicknesses and finishes.
I think it's still available.
or Ventubelite aluminium honeycomb panel, very light but probably not as good an insulator.

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Follow Up By: The Bantam - Wednesday, Nov 18, 2015 at 23:24

Wednesday, Nov 18, 2015 at 23:24

there are all sorts of exotic panel materials ..... but ya don't have to go too exotic to get some massive advantages over typical caravan construction ....... the lightweight plywood, glass mat & epoxy is reasonably easy to work with and a bit more forgiving than the exotic composite materials.

I have had saples of some of the hollow core products ... but have not played with it because of the cost ...... there are some realy good light weight plywoods arround, like palwonia & gobbon that are not a hell of a lot dearer than radiata or hoop .... and 50 to 75% the weight.

Combones with glass and epoxy these light weight ply woods can produce some spactacular strength to weight , without the sudden failure characteristic of the more exotic products.

One thing that is woth a look is foamed PVC board ..... its not expensive about half the weight of radiata pine ply, about twice as strong and has a realy slow failure characteristic.

cheers

FollowupID: 861045

Follow Up By: eaglefree - Thursday, Nov 19, 2015 at 23:01

Thursday, Nov 19, 2015 at 23:01

Thankyou everyone for your replies. We have just finished ordering all of our materials for the build. Also the last 4 days has been a period of building the floor frame.

The weight now is at 121 kgms. This includes the wheels, axle, springs, floor frame and drawbar.

I suppose this low weight to date proves that the old cart spring conventional suspension set up can be relatively light in overall weight if small 10" wheels are used.

I've ordered the roof ply. I also have 13mm polystyrene sheets to sandwich between the roof ply and the inner wall ply. As the wall frame will be made of 13x13x1.8mm square tube this thickness is perfect. I don't intend to use ply for the exterior of the walls, only the roof.

So the challenge isn't over. 79kgms left to my goal of 200 kgms. its a 50/50 chance of making it as I only have 6mm floor ply, bed frames, roof ply, roof aluminium cladding and wall cladding, shower wall, shower tray, water tank, sink and sink frame, lights and wiring. All these will add up in weight but reckon I might make it.

Cheers

FollowupID: 861095

Reply By: eaglefree - Wednesday, Nov 25, 2015 at 19:21

Wednesday, Nov 25, 2015 at 19:21

Here is the frame partially done. The floor frame including the drawbar, wheels, axle, springs total weight 121 kgms. Not bad, a little more than anticipated.

Now to finish the frame, reinforce it with webbing bits then floor, roof ply, electricals and so on.

Will I go over 200kgms tare? likely at this stage a little over but you never know. the upper frame is really lightweight with 13x13x1.8mm tube and ripped 20x20x2mm gal tube.

AnswerID: 593124