Custom Slide on Camper Design Advice

Submitted: Sunday, Jun 17, 2012 at 12:17
ThreadID: 96325 Views:13917 Replies:17 FollowUps:14
This Thread has been Archived
Hi Guys

We're a young couple (+ cat) from north Brisbane designing a custom slide on camper with the intent to travel around Australia. We're hoping to have the camper built by the end of October (fingers crossed!). I just haven't told the misses its October…. 2013 :)

The Camper:
Welded box aluminium frame clad in CNC cut alucobond panels attached with sikaflex
50mm EPS insulation
Hard side pop up (12v linear actuators)
5 x Camec 1175x565 jupiter windows
North-South double bed
Hi-Macs acrylic benchtops
Internal alucobond cladding secured with VHB tape
keyless digital door lock
webasto dual top diesel hot water and air heater
sparrow roof top air conditioner
potable water tank
sink with mixer tap and lid
sump with 12v pump for grey water
portapotti in drawer
LED lighting throughout
12v washing machine
12v fridge
supercombi 3000W inverter/charger
2 x 190w 24v solar panels through 40A MPPT
2 x 200AH 12v AGM batteries
Estimated Weight: 920kgs

The Trailer:
potable + grey water tank
rubbish storage
possible extra solar panels on roof of trailer?
misc gear

The Annex:
2 x 2.5m fully enclosed canvas (cat escape proof) annex
Entry from left or right side through floor to ceiling doorway

The Ute:
Mazda BT-50 DX 3000
Custom tray with150L centre mounted water tank below tray
Lockable storage container behind cab
Upgraded leafs to carry approx 1200kg

Left side:
Right Side:
From Bed:

We are looking for any ideas, opinions, improvements, and anything that we've missed. Any and all feedback appreciated. We are also looking for an electrician with camper experience to help with that aspect of the design (paid contract, please message us privately).

Much Appreciated,

Leisha Shannon
Back Expand Un-Read 0 Moderator

Reply By: Wayne (NSW) - Sunday, Jun 17, 2012 at 12:30

Sunday, Jun 17, 2012 at 12:30

If I have read this post correctly, you want a slide on camper plus a trailer.

It will be all to much for the Mazda. The vehicle is too light in the chassis to carry all that weight.

AnswerID: 488717

Follow Up By: racinrob - Sunday, Jun 17, 2012 at 13:06

Sunday, Jun 17, 2012 at 13:06
Leisha, I agree with Wayne and I'm speaking from experience, I had a Compass solid sided pop-top camper on a tabletop LandCruiser. The dry weight of the slide-on was 750kg but all up wet over the weigh-bridge with extra fuel, 130 liters of water and so on prior to a trip just a tad under 5 tonne, the Mazda might handle that and tow a trailer but it's a big big ask. JMHO.

rr VKE237 6678
FollowupID: 763855

Follow Up By: Member - Joe n Mel n kids (FNQ - Sunday, Jun 17, 2012 at 13:52

Sunday, Jun 17, 2012 at 13:52
Hi guys, dont want to also scare you off but it may require you to think in reverse and design what you want then find the car that will take it ..... it is not just the Mazda i will add, i have seen a few different makes now and it seems to be the newer ones but i think the reason is the load rating are higher and far more power and the same (looks) chassis ....
Other than that what program did you use to draw it ???? looks really good ..
Image Could Not Be Found
FollowupID: 763860

Follow Up By: Inflataduck - Sunday, Jun 17, 2012 at 19:24

Sunday, Jun 17, 2012 at 19:24
agree with both
had L/cruiser & Patrol both crack chassis's, I've used patrol 6wheelers for the last 2 vehicles & no problems but they both have the chassis beefed up & have a 4500 gvm
will you be legal when loaded & with all that wind age & load will you get any fuel economy?, I know that i get better economy with my 4.2ltr td 6wheeler towing my mates 6.25mtr boat than he does with he's BT-50, empty he kills me
FollowupID: 763878

Follow Up By: Nomadic Navara - Wednesday, Jun 20, 2012 at 16:01

Wednesday, Jun 20, 2012 at 16:01
Was the Mazda fitted with air bags?
Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

FollowupID: 764160

Reply By: splits - Sunday, Jun 17, 2012 at 13:33

Sunday, Jun 17, 2012 at 13:33
It looks very good but I agree with the others, are you sure the ute is going to carry all of it? I looked up the specifications on Mazda's site and the highest carrying capacity for any 4x4 model in that range was 1411kgs. The manufacturer has no idea what any owner is going to put on the car so the specified weight is for a bare cab/chassis with a near empty fuel tank. From that you have to deduct the weight of the custom tray, your own weight, a full fuel tank, your water tank weight plus its contents, the tow bar weight, the weight on the tow ball, your camper weight, any other accessories plus anything you put in the camper or the cabin of the car. I think you are going to be well over the car’s capacity.

The areas you intend taking the car could also be a problem. Maximum towing and carrying capacities are for good highway type conditions only and should be reduced in many off road situations. Volume selling cars of this type and size should not be stretched to the limit in the worst conditions they are likely to encounter. Few people pay any attention to this which is why the Outback service centres do a roaring trade repairing broken chassis, diff housings, wheel bearings shock mounts, wheel studs etc.

Regarding a shower: I have seen permanent ones built into slide on campers but the majority don’t have them due to restricted space. A simple idea that my wife and I have used successfully for many years is a fibreglass tray placed temporarily in the centre of the floor. Ours measures 650mm square and about 100 high. It has a drain tube glassed into one corner which goes down through a bath plug in the floor. A shower curtain attaches to velcro around the top inside edges of the tray and hangs from the roof with elastic loops. A bucket of water is more than enough for both of us while the shower is just a cheap 12 volt hand held one from a camping store. The tray sits on the bed while travelling and is placed inside the car overnight.
AnswerID: 488719

Reply By: Member Andys Adventures - Sunday, Jun 17, 2012 at 13:51

Sunday, Jun 17, 2012 at 13:51
I noticed that it is 2 meters wide, will you get it registered that wide as the widest I could make mine was 1.8 meters
AnswerID: 488720

Reply By: Member - Joe n Mel n kids (FNQ - Sunday, Jun 17, 2012 at 14:19

Sunday, Jun 17, 2012 at 14:19
Hi again, now to get away from the chassis bit i will list a few things for you to think about after reading the top and having a think about what i see here every day ..... we live in Doomadgee Far NQ and it is remote, also lived halfway up the Tanimi and in Arnhem Land so we have a good idea of what does and does NOT work ......
First ..... sorry to give you the bad news but the cat wont be able to go with you, if it is simply a MUST then cut your travel plans in half..
50mm insulation seems a bit excessive, every 2" added takes away storage space and 2", overall 4" is a LOT of space ... in a van where you actually "live" in it yes insulate but it is a camper and all going well you wont spend much time in it, dont kid yourselfs that you will not stay in accomodation, you need a break from the "camping" after a while ....
Keyless lock will stuff up with dust abd viabrations, "KISS" ... keep it simple ...
The "stuff" that uses water seems excessive for a couple, a washing machine can be the same bowl you wash dishes in and seems like you want all the stuff a caravan has in a tray camper, it simply wont happen ....
In short it is a good plan but it all adds up to a good camper trailer needed and you say you want to tow a trailer so i would start looking at good camper trailers, the market is getting tight at last and some good deals out there, you CON NOT build for what you can buy it now unless you are fully set up to do so, a heap of camper second hand are on the market now as people have brought them and find they hardley use them and quit then at half the cost and some even have simple showers and toilets in the, the ability to un-hook and set up and drive off and leave it ALL set up is priceless in the bush, having it on your tray even if it is a "slide off" is a major pain in the butt, slide it off and you have an empty tray, you want to go fishing or what ever you have to get it out from trailer or camper and re pack it on the ute then all in reverse when you pack up, un-packing and packing up are the biggest curses of travelling .....
My advise is go hire a camper trailer and spend some weekends away .....
AnswerID: 488721

Reply By: Leisha Shannon - Sunday, Jun 17, 2012 at 14:28

Sunday, Jun 17, 2012 at 14:28
Thank you for all of the informative replies, this is a great forum!

This has been the most troubling aspect of the design, and one we have given quite a lot of thought to.
We are intending to use the single cab with a 1415kg rated payload.
We have estimated the dry weight of the camper at 470kgs , with 430kgs of gear (fridge, power stuff, personal effects, etc), 150kgs for the two of us , 60kgs of diesel, 90kgs for tray, giving us a total payload of approximately 1200kgs.
We had originally hoped to carry water on the ute/camper however this would push us too close to the 1400kg max payload, so we came up with the idea of towing a small trailer of approximately 400kgs to carry water , generator, 2 x 20L jerry cans and rubbish.
When we setup for an extended time with the camper off the ute we can do a "water run" every few days to fill the 150L tank in the ute + tank in the trailer while the camper stays put.
Our plans so far is to travel slowly, mostly on sealed roads with no crazy 4WDing.

QLD Transport website states a load on a ute must protrude less than 15cm either side of the width of the vehicle. The width of the ute is 185cm giving a maximum possible width of 215cm. We have gone slightly less than this to accommodate a change in vehicle if required in the future.

Splits : Thank you, thats a fantastic idea for the shower!

Thank you for the replies so far!
AnswerID: 488722

Reply By: AlbyNSW - Sunday, Jun 17, 2012 at 15:27

Sunday, Jun 17, 2012 at 15:27
As said by others, I would be looking to shed a few kilos. Do you need 400ah of battery plus solar panels plus a generator??
AnswerID: 488725

Follow Up By: Nomadic Navara - Wednesday, Jun 20, 2012 at 16:34

Wednesday, Jun 20, 2012 at 16:34
Batteries weigh as much as 35 kg per 100 Ah.

Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

FollowupID: 764166

Reply By: Ozhumvee - Sunday, Jun 17, 2012 at 18:09

Sunday, Jun 17, 2012 at 18:09
Agree with the others none of the mid size utes will handle the load long term, even a Cruiser or Patrol will know its on the back.
No mention of cooking facilities but as you are already fitting a Webasto thermo top fit a Webasto diesel cooktop as well.
If you increase the solar and batteries to around 500w and 480ah you will have the same capacity as we have in the Oka and can leave the gennie at home. We use a 240v 1000w electric jug and a normal 240v toaster through the inverter as well as all the plugpacks to charge camera, laptop, Kindles etc.
You could get away with a smaller 1800w PSW inverter too as we have found it is more than enough.
Think about just using the insulated panels without a frame, just stuck together with Sikaflex, a couple of Oka owners have just done that and it is extremely strong.
AnswerID: 488738

Reply By: Ross M - Sunday, Jun 17, 2012 at 18:14

Sunday, Jun 17, 2012 at 18:14
All sounds fantastic but the BT50 won't carry much more than 500kg continuously and especially if it is used anywhere off road where road conditions will work it well past it's capacity. Land Rover derate their towing/carrying capacity by half in these conditions.
Just because it may be rated 1 ton ,that means in the most favourable, least stressed situations it may survive.

The rear axle strength and the chassis cross sectional area isn't anywhere near what is required.
If you look at BT50, not the new one, you will see the chassis is smaller and thinner than Colorado/Dmax/Nissan and they have been known to fail when overstressed.
Me thinks a rethink is on the menu.
AnswerID: 488739

Reply By: Crackles - Sunday, Jun 17, 2012 at 18:49

Sunday, Jun 17, 2012 at 18:49
Leisha a few things to consider:
*With so much of the camper protruding out past the ute, fuel consumption will be poor.
*The width & height will cause issues on narrow tracks or cleariance from trees.
*For a camper of that size I'd suggest it will weigh as much as 200kg more than your estimate.
*Rear access doors are historically difficult to dust seal.
*A cat will restrict where you can travel. As the majority of attractions around Oz are in National Parks you either can't go there or will have to find catteries. Not fair on the cat either locked up in the car for that time.
*Towing a trailer defeats the advantages of having a slideon. May as well just tow a van if just sticking to sealed road.
Good luck with your project & travels.
Cheers Craig................
AnswerID: 488742

Follow Up By: Inflataduck - Sunday, Jun 17, 2012 at 19:05

Sunday, Jun 17, 2012 at 19:05
agree with crackles
by filtered air pressurisation this will stop dust problems
FollowupID: 763873

Follow Up By: Member - Phil G (SA) - Monday, Jun 18, 2012 at 19:41

Monday, Jun 18, 2012 at 19:41
I also agree with Crackles, but easiest way to stop dust problems is to not have a rear door. No air pressurisation needed.
FollowupID: 763979

Reply By: Inflataduck - Sunday, Jun 17, 2012 at 19:01

Sunday, Jun 17, 2012 at 19:01
why don't you consider a (GRP) foam/end grain balsa sandwich construction all bench tops cupboards etc can all be made using the GRP foam sandwich construction making it even stronger & light at 920 kgs its too heavy, , I've had problems with linear actuators & would not use them on any project again & would not fit a roof air con, you need to get as much weight as low as possible
you may even find by having the slide on that extra bit back can cause some driving conditions dangerous EG, on my old l/cruiser & patrol if i slip the camper back 300mm to fit extra crap near the head board on a dirt rd they both had a bad habit of loosing steering & pushing fwd
Good luck I,m on my fourth slide on & presently making my fifth
AnswerID: 488744

Reply By: Leisha Shannon - Sunday, Jun 17, 2012 at 19:38

Sunday, Jun 17, 2012 at 19:38
Joe n Mel n kids:
Thanks for the heads up regarding the lock. KISS definitely sounds like the way to go.
The sketch was done in "Sketch Up" a free 3d surface modelling program thats really easy to use. What do you mean when you say we'd have to halve our travel plans if we bring the cat? We are aware he will need to visit a cattery when we're visiting national parks, but is there something else we're not yet aware of? Unfortunately, not taking him is not an option.
The 50mm insulation was chosen because we're planning to do tasmania / the snowy mountains, and some hot places. The slide on will fit in a shipping container so there is the possibility of international travel too . We figured the more the better as anything we can do to save energy heating/cooling the camper is a good thing. The frame is 50mm square box section so the insulation should fit inside it nicely.
We will be living full-time while working so the washing machine is appealing.. The water consumption is quite high (50+L/load) so we wouldn't be able to use it while in remote locations. We found the hand operated wonder wash ( ) , however this doesn't appear to be big enough to wash bed sheets. Does anyone have any alternatives ?

We've been umming and ahhing over taking a generator vs carrying additional batteries and are leaning toward the generator for a few reasons.
A second "alternate" source of power compared to all our eggs in one basket is desirable.
We should be able to do all of our "high power" tasks within 1-2 hours (cooking dinner, washing machine, charging batteries ) while the generator runs.

What problems have you had with the linear actuators? We are planning to have the mounting points externally accessible so that in the event of a failure they can be removed and roof opened manually.

What vehicles would you recommend we look at to handle anticipated load?

Thanks for the great feedback!
AnswerID: 488755

Reply By: Member - Geoff M (VIC) - Sunday, Jun 17, 2012 at 21:21

Sunday, Jun 17, 2012 at 21:21
Hi Leisha Shannon,

Good on you for doing the work planning your trip, and actually planning on doing it! However I have to agree with many of the other replies to your post in that the Mazda is just not up to it regarding weight.

I currently have a Mazda BT50 freestyle (2007) and carry a slideon camper that weights approximately 400kg's unladen. Even with upgraded suspension the chassis on my Mazda cracked on the Canning Stock Route last year, and subsequently I had the chassis strengthened and wheelbase extended. The next failure was the rear axle housing which resulted in the LHS wheel & axle leaving the vehicle. Even though I was under the vehicle GVM this happened. Everything has been repaired, but I have and will not carry any load in this vehicle again and are currently looking at replacing it with something stronger.

Consider seriously everything you plan on carrying, I can't stress enough about minimising the weight. The BT50 may do the job for you if you stick to the bitumen, but that would mean missing much of the fantastic places off the beaten track.

Good luck with your planning, and have a good trip.

Cheers, Geoff
AnswerID: 488769

Follow Up By: wombat100 - Monday, Jun 25, 2012 at 12:47

Monday, Jun 25, 2012 at 12:47
Hi Geoff
Over the weekend, I had a yarn with a bloke in the Tech side of Mazda here in Sydney. He actually designed and specified the chassis/suspension upgrade modifications for our BT50.
I showed him your report here (a while back) on the failures of your BT50. He thought he had seen a report on your vehicle from a dealer.
He reckons there is far more to the story than you are letting on..and I tend to agree !!
ALL vehicles have some limitiations, and reading your specs with diff locker and winch installed, I think you expected the BT50 to exceed those limitations.
We do not "stick to the bitumen" with our vehicle, and in fact have done many thousands of Kms of outback 'off the blacktop' touring, with many more to go.
No- the Mazda will not ' leap tall buildings' but it has got us through a lot of pretty tough situations. I find the standard diif is very adequate, and I don't get into a situation where a winch would be required. But I do carry an inventory of recovery gear.
The mods on ours were carried out before the camper was installed- with the whole job being engineered- not just a necessary repair job like yours.
Yes, we do have and use airbags, and used properly and as they are designed for, make a huge difference to vehicle handling, load carrying and overall minimising undue stresses. I suggest who ever gave you the negative air bag information probably knew no better.
Cheers for now
FollowupID: 764517

Follow Up By: Member - Geoff M (VIC) - Monday, Jun 25, 2012 at 13:52

Monday, Jun 25, 2012 at 13:52
Hi David,

You can check the various posts that I have submitted on the problems with my BT50 including the information above, and I have tried to be as accurate as I can be. I have contacted Mazda regarding the recent failures and spoke to head office - they had a copy of all the previous warranty failures and listened to the latest problem/s, thanked me for my input, and then basically said I was on my own from there! Maybe there was a report from the dealer - however despite trying several times I got no response from my original dealer.

I had low expectations of our BT50 and never expected it to tackle the difficult 4WD tracks - had set it up mainly as a touring vehicle. The winch was insurance as we travel alone quite a lot and I transfered it from my previous vehicle, and the diff lock was included to try and cover for the limited wheel travel due to the IFS. I had never taken the BT50 on what I consider hard tracks - I believe all the failures occurred from driving on corrugated tracks that were mainly driven in 2WD.

I don't believe that the BT50 is much different to the other meduim duty 4WD utes currently on the market in regards to overall strength, however I believe that none of these vehicles are suitable for long term outback travel carrying loads. After the last failure I had the vehicle independently checked and the verdict was that it was unsuitable for carrying the modest loads I require to carry. You will obviously disagree with me and that's fair enough - last year I would also have totally ageed with you.

David - I hope that you do not experience the failures I have had and that there are many years of trouble-free and safe traveling with your vehicle. I hope to have the same - unfortunately in another vehicle as the days of traveling in the BT50 have come to an end for us.

Cheers, Geoff

FollowupID: 764520

Reply By: Tonyfish#58 - Monday, Jun 18, 2012 at 16:55

Monday, Jun 18, 2012 at 16:55
Kiss is the way to go - Mine is home made out of alloy sheeting.

Once you start fitting these out you will add weight quicker than you can calculate.

Mine has a Roof top tent with storage below and swing out kitchen. I have rear compartments that I have no issue with dust.

My seal design has worked very well

I carry everything on our ute and we take it everywhere.

Slide on

Reply if you want greater detail for this type of design

Regards Tony

AnswerID: 488823

Follow Up By: katepaul - Saturday, Jun 23, 2012 at 15:49

Saturday, Jun 23, 2012 at 15:49
Hi I have just found this forum I would love to see more detailed photos of your set up as we are planning something similiar any help would be appreciated
thanks kate
FollowupID: 764394

Reply By: Member - Phil G (SA) - Monday, Jun 18, 2012 at 19:55

Monday, Jun 18, 2012 at 19:55
I guess by now, you are doing some rethinking. In my opinion you need a 4.5 or 6T truck (like a Canter or Izuzu 4wd) to fit what you've planned. If you still are interested in this concept, then google Earthcruiser or All Terrain Warriors - a lot of ideas crammed into those two even though they are not slide-ons.

I'll fess up to not being a fan of slide-ons. From what I've seen, 90% of slide-on owners give up sliding the thing off - too much effort required and even more effort to get it back on.
AnswerID: 488844

Reply By: Leisha Shannon - Monday, Jun 18, 2012 at 22:40

Monday, Jun 18, 2012 at 22:40
Thanks for the feedback regarding the choice of vehicle. We are currently looking at Ford F350s as these appear to have a payload of around 1900kgs which would mean we can ditch the trailer and carry our water on board safely.

Is there any other similar vehicles we should be looking at?
AnswerID: 488870

Follow Up By: Nomadic Navara - Friday, Jun 22, 2012 at 12:55

Friday, Jun 22, 2012 at 12:55
This one was returned too the vendor but I believe it is still for sale as a package Site Link

Other suggestions are - Site Link - Site Link -
Retired radio and electronics technician

Lifetime Member
My Profile  Send Message

FollowupID: 764273

Reply By: Leisha Shannon - Friday, Jun 22, 2012 at 13:08

Friday, Jun 22, 2012 at 13:08
Thanks all for the replies. We have decide that a ute based solution isn't appropriate due to our weight requirement so we are investigating light truck based 4x4s and associated camper bodies.

Back to the drawing board!

AnswerID: 489145

Follow Up By: Member - wicket - Friday, Jun 22, 2012 at 17:45

Friday, Jun 22, 2012 at 17:45
How much do you want to spend ? earthcruiser has it all sorted for you

FollowupID: 764308

Follow Up By: katepaul - Saturday, Jun 23, 2012 at 15:53

Saturday, Jun 23, 2012 at 15:53
Have a look at metal fabricators Wilmax they have done a great one was in one of the 4wd magazines
FollowupID: 764395

Reply By: Leisha Shannon - Saturday, Jul 21, 2012 at 17:15

Saturday, Jul 21, 2012 at 17:15
We have taken the comments regarding weight onboard and decided a 4WD light truck configured as an expedition vehicle is more suitable for our needs.

Isuzu NPS300 or Mitsubishi Canter (we are leaning toward the NPS based on feedback so far)
Single Rear Wheel conversion , ATW suspension
Bullbar, over cab storage rack, winch

Subframe / Tray :
Steel subframe, spring mounted (Army style)
3 x 150L external water tanks, 1 x 150L grey water tank.
Storage boxes


lightweight aluminium base frame with aluminium angle covering edges.
Hard shell 50mm van glass composite FRP panelling for the floors, walls, roof, and internal divisions
Sikaflex glued construction
4.2m long x 2.1m wide
Camec Jupiter windows with second acrylic sheet for double glazing
Fully enclosed annex (2.5m x 2m)
externally accessible storage area

LED lighting throughout
webasto dual top diesel hot water and air heater
sink with mixer tap and lid
sump with 12v pump for grey water
150L internal water tank
Thetford Cassette Toilet
North-South Double bed over lounge area with pulley system to raise and lower.
Wall mount airconditioner
130L 12v fridge, Microwave convection oven, washing machine, misc appliances.
4 x 190W solar panels , 12v 750Ah AGM, 3000w inverter/140a charger

Floor Plan:
Left Side:
Right Side:

We are looking for any ideas, opinions, improvements, and anything that we've missed. Any and all feedback appreciated.

Thanks again,

Leisha n Shannon
AnswerID: 491376

Follow Up By: Crackles - Saturday, Jul 21, 2012 at 19:44

Saturday, Jul 21, 2012 at 19:44
"We have taken the comments regarding weight onboard"..... Really?

You're looking to carry over 600 litres of water. (That's more than a slip-on fire fighting tank!) Add the 200kg of batteries plus all the upgraded/extra items that weren't in your original design & now you're on your way to overloading an Isuzu truck with a 3 tonne payload.
Rather than re-inventing the wheel, can I suggest having a look at what is already proven to work & commerically available then customizie a design around them. As an example having a fully enclosed anexe is fine for a caravan but on a truck/camper it means you can't shift if you need to drive to town to get some groceries & why existing campers like this will usually just have a retracable shade sail that can be pulled in quickly.
Have a look at the best in this class Earth Cruiser & look at their specs for ideas. eg: total of only 190 litres of water to keep weight down.
Good luck with the project & please post update photo's when the build begins.
Cheers Craig.............
FollowupID: 766852

Sponsored Links