Newbies designing their BTs

Submitted: Friday, Sep 12, 2003 at 23:32
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I have been following, with interest, various posts regarding BT design issues. There appears to be many people currently undertaking detailed analysis of their future BT requirements. Currently I am progressing a design for a 19-20’ BT and I am reviewing the best method to get the most efficient rig and value for money. One particular issue, is that I am in agreement with Collyn that $5k of solar to run a $1.5k fridge is a bit excessive and that it is most likely more efficient to run a tropicalised absorption fridge. Moreover, there are all the other inclusions to be considered, such as water heaters, stoves/ovens, batteries, pump, water tanks, microwaves, TVs/aerials, heaters, aircons (types, capabilities, ruggedness, suitability, practicability etc). I am developing a spreadsheet covering all requirements and thought that it might be appropriate and synergies achieved if details, design issues and information could be exchanged. Thankyou to the BT owners who have provided so much valuable information. Dusky
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Reply By: Deleted User - Friday, Sep 12, 2003 at 23:34

Friday, Sep 12, 2003 at 23:34
Dusky If you don't mind warm beer north of Capricorn, by all means go with a "tropicalised" absorbtion fridge! Myles
AnswerID: 559596

Reply By: Andy1 - Friday, Sep 12, 2003 at 23:35

Friday, Sep 12, 2003 at 23:35
Dusky One of the wonderful, possibly apocryphal, stories concerns JP Morgan, the great US Banker, being asked what was the cost of operating his Steam Yatch. His reply was supposed to have gone something like, "If you have to ask the operating cost you can not afford one". Collyn is no doubt correct that Solar Panels & Batteries are perhaps the expensive path, but to what end? To live well outback, or really anywhere, you need a compressor refrigerator, the issue is not the cost of the fridge but the benefit of the solar. We started with 3 solar panels & 3 batteries & are about to add the 4th battery to ensure fridge power at all times where possible. I am not even a beer drinker, but of course can not deny, based on photographic evidence, a taste for a drop of red. Up the mighty Lions! Andy
AnswerID: 559597

Reply By: Deleted User - Friday, Sep 12, 2003 at 23:36

Friday, Sep 12, 2003 at 23:36
Could I just throw into the pot ............. Yes 5k of solar is expensive ...... but only around 6 % of the purchase price but is 90 % of your independence from 240v power (and civilisation) the other 10 % being 8 water and 2 food or 10 % alcohol [smile] The power demand has grown (substantially) since purchase (in our BT anyway). The secret is your upgrading/expansion capability should be there at purchase ...... later, add a panel or two if the need arises. Use a 30amp solar reg instead of 20amp for a little extra instead of having to buy a 30amp later. If the expansion capability is there (wiring/regulator/charger) the next owner will have no trouble adding solar (if you dont) thereby increasing resale. Have you calculated gas consumption on a 200l fridge/freezer for say 14 - 30 days ? It would have to be around 500g per day ..... my Chescold 60l uses around 400gpd. Regards Anthony Explore this Great Land ... Do it Easy ... Tow a Bushtracker
AnswerID: 559598

Reply By: Deleted User - Friday, Sep 12, 2003 at 23:37

Friday, Sep 12, 2003 at 23:37
My advice re thinking hard before spending a heap of money on solar to drive a fridge - primarily concerns BIG electric fridges. The 300-litre units that many motorhomers feel necessary require at least six big modules. To provide a good margin up north one needs eight. On top of that one needs a large battery bank and really a back-up generator.

This is serious money and also weight. I've come across quite a few rigs where over $9000 has been spent to drive a big electric fridge.

I do usually stress it is substantially an economic argument - for motorhome types. With caravans though, the rigid loading constraints of the lower priced units (commonly 300 kg for single axles, 450 kg for doubles) usually totally precludes the weight of modules and batteries required. In this respect, BTs are a rare exception.

I totally agree with Anthony's advice to ensure the solar regulator etc is larger than initially required to allow for system expansion. Ditto cabling!

Re Myles point about warm beer. A 'tropicalised fridge' is not the same thing as a fridge rated to 'Climate Class C' (e.g. current RM 2453, RM 2553, RM4601). It's unfortunate that the term is used - but I did not invent it.

Most fridges are designed for ambients not exceeding 32 degrees C. 'Climate Class T' fridges on the other hand are designed to operate comfortably at ambients up to 43 degrees C. I have yet to come across anyone who has one (that is correctly installed) who is unhappy with the performance - even in a Darwin or Broome summer.

However unless a three-way fridge IIS 'Climate Class T', I would not personally consider using it in very hot climates - I too dislike warm beer!
Collyn Rivers

AnswerID: 559599

Reply By: Noosa Fox - Friday, Sep 12, 2003 at 23:38

Friday, Sep 12, 2003 at 23:38
Personally we love our 21' van that is really a luxury home away from home, but we have a 7.3lt F250 with intercooled Turbo to pull it. The extras that we have that are costs above the BT standard basic van are:- Aluminium checker plate along the sides. Aussie traveller awning with annex. (The annex has been used twice in just over 2 years) Shower /Toilet. We have standard width but I think 100mm wider would be better. (your physical size here is a consideration) A fan assisted vent above shower is a good addition. Hot water has remote ignition We have upgrade to Caprice 4 burner stove and oven. Hardly ever use the gas oven so a different type of hot plate only is a consideration. We have 5 water tanks, 4 for general use and 1 drinking. It is amazing how much water you use in shower. The standard water pumps that BT use are very good. We have 3 by 120 watt solar panels and 4 batteries that has 50amp battery charger for when in cloudy conditions. Only on rare occasions do we require to use the battery charger though. I believe the Glass mat batteries that BT are now using are very good. 190lt 2 door 12volt refrigerator. Highly recommended. 1800 watt pure sine-wave inverter. Useful when using microwave for short bursts (5 to 10 mins max) as they use a lot of power. Other than than a much smaller one would suffice for running all the other 240 volt things when away from mains power. We have a Winegard TV antenna which works good, but requires rubber pads under the fins to prevent vibrations. We have radio/CD player without external speakers and wish we had the external ones as well so that you don't have to turn volume up too loud to hear it outside. Large cargo doors on each side make storage easy. Light with handle beside the door is good. Rear view cameras are a nice to have item, but most people get along quite well without one. (We don't have one) In your layout don't put too many heavy items at the rear of van as it can upset stability of van when towing. (We had a rear pantry and found that we had too much weight in it and had to move items forward to get weight distribution right. It is amazing how much weight you have with sugar, flour, tin foods and all the other cooking items. It is not hard to have 100kg or more) We have wind down support legs, and would be without them. If you want to try van without, at least have BT weld some suitable brackets to chassis while under construction so that they can easily be attached later if you require them. A tap on draw bar is handy. 12" brakes provide very good braking. Flick mixer taps on sink and shower are also worth considering. We have a microwave, but it only gets limited use so you might like to leave that out if you are going to spend a lot of time away from mains power. We have air conditioner that can be operated from 2kva generator if away from mains power in very hot weather. If you don't get the air con, at least have van wired so that one can be fitted later. In cold weather the Webasto diesel heater is also a very good addition (about $2000 though) I fitted lights in cargo area, and grab rail just inside door along with towel rails etc. These are easy to do yourself and help to personalise your van. There are so many variations of extras to choose from but not all are necessary. Think carefully about what you put in as everything that you add increases the weight that you have to tow around, and that in turn increases the fuel consumption. Brian
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AnswerID: 559600

Reply By: Rockgoc - Friday, Sep 12, 2003 at 23:39

Friday, Sep 12, 2003 at 23:39
Hey Brian, we are pretty interested in why you have elected to fit wind down stablisers on the van. BTi told us they were not neccessary, and we didn't argue the point, but we always wondered why BT didn't need them. So do you reckon they are an absolute must? Our van is in the chassis stage, and has been put to one side in the factory until a completion date in March, so do you think it's too late to have the wind downs fitted? I'd rather have them, than have a home which makes me sea sick! Give us your thoughts please! Regards, Jan & Ian
AnswerID: 559601

Reply By: Noosa Fox - Friday, Sep 12, 2003 at 23:40

Friday, Sep 12, 2003 at 23:40
Hi Jan & Ian, Steve and I will always disagree on this point. Steve doesn't believe that you need them, but I believe that the Bushtracker is no different to any other caravan. Any caravan with pneumatic tyres has movement when someone is moving around inside the van. The pneumatic tyre on the jockey wheel also allows movement. I had 4 swing down the adjust legs fitted some after we picked up van, they are manufactured by Preston Chassies in Melbourne. At Cania Gorge about 90% of vans had some type of support under the vans, some had the wind down type like mine. others had portable ones and I think the other 10% will be putting something under their vans in the future. The swing down then wind type now being manufactured by Vehicle Components, Brisbane who make the tow hitch, is a much stronger one than the ones that I have, and several members have these fitted. There are a few BT in Tassie, and I know some are going down there soon so you should be able to arrange to meet with one of them and sit in their van, while someone else walks around in side. You will then be able to decide for yourself if you want them or not. Either 2 on rear and a centre wind down support on the front would probably be sufficient. We also have a wind down one on the A frame (Like a jockey wheel with solid plate on bottom) and when this is put down withe the van still connected to vehicle then it steadies everything up. Brian
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Reply By: Deleted User - Friday, Sep 12, 2003 at 23:41

Friday, Sep 12, 2003 at 23:41
I also have the Vehicle Components legs fitted. I bolted them on rather than welding just to be able to remove them if I ever have the need. They certainly stabilise the van. As we have kids with us every trip they would be in/out ..... and we got plain sick of the van rocking. Problem solved after fitting the legs. I thought BTi had these legs in stock for the customers that requested them ????? Maybe not ............. ????? Anthony Explore this Great Land ... Do it Easy ... Tow a Bushtracker
AnswerID: 559603

Reply By: Bushtracker42 - Friday, Sep 12, 2003 at 23:42

Friday, Sep 12, 2003 at 23:42
Hope I’m answering this the right way. We are new
to the site after hearing of it from a couple from Noosa who dropped into a
rest stop near gympie 5 weeks ago while we were heading north. They were
without their bushtracker but we had stopped to meet another BT parked there
for lunch.

We head about the ‘meeting’ of BT’s,
but not sure where/when until we got back today and found the web site. As
we are still in pre-retirement toruing mode, (holiday’s and weekends
only), we had an agenda this trip and could not make it anyway.

Re leg/support. We added a front leg, just a bolted
bracket on the A frame with std caravan clamps allowing us to drop a 2”
pipe with base down. We know some others who have rear wind down supports
bolted on, but we are in no rush for this mod as the front has made a large
difference/improvement and lets you take the load off the jockey wheel.


Gary Harding

TriSys Engineering/III

AnswerID: 559604

Reply By: F Troop - Friday, Sep 12, 2003 at 23:43

Friday, Sep 12, 2003 at 23:43
I'll put my two cents worth in re legs, Good things!!!!! I'm a big bloke and when I move around so did the van, BT fitted the VC legs for me before pick up, and they did a top job. I love them. Paul and George both picked up legs on the way home from Cania so that should give you a clue as to there worth. Graham
AnswerID: 559605

Reply By: Dusky - Friday, Sep 12, 2003 at 23:44

Friday, Sep 12, 2003 at 23:44
I would like to thank everyone for their advice and comments. All information received here and elsewhere in this forum and in particular those people that e-mailed me have been most appreciated and the advice is helping to clarify my BT design. Thanks again, Dusky
AnswerID: 559606

Reply By: Deleted User - Friday, Sep 12, 2003 at 23:45

Friday, Sep 12, 2003 at 23:45
Dusky et al, One of the great things about the B.O.G. ..... getting heaps of ideas from so many people that use them and hopefully some solutions to the little things (personal to your van) that make the delivery of the BT a day to remember. Between BTi and the B.O.G. a Bushtracker delivered now must be in its best " No Regrets" form ... fiscal limitations aside. I feel sorry for the people who go through the whole process (especially the restless nights near the end) without ever seeing the forum. Of course the restless nights disappear the day after delivery ........ [smile] Anthony Explore this Great Land ... Do it Easy ... Tow a Bushtracker
AnswerID: 559607

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