PDA

View Full Version : Sand



bigbugga
6th August 2003, 09:44 PM
The fundamental theme with sand driving is to conserve your momentum. Since traction is at a premium, any increase in speed can be difficult, if not impossible, and you do not want to lose any momentum, as you may not be able to regain it.

Tire Pressures

The first thing to do before driving on sand is to lower your tire pressures. This is done to provide better flotation by increasing the size of your "footprint" and thus dramatically improving your traction. It also reduces the amount of strain on your vehicle and minimizes wear and tear on the tracks.

The optimum tire pressure depends on your vehicle, the type of tires fitted and the terrain. The following technique provides a good starting point to find the optimum pressure and is best performed before leaving the bitumen.

Park your loaded vehicle on a level surface and place a brick 1 cm away from the sidewall of your rear tire. Deflate that tire until the sidewall just touches the brick and then measure the tire pressure. Use this pressure as your starting point when initially lowering your tire pressure for sand driving. As you become more familiar with sand driving, you con alter this pressure as the terrain dictates.

If you haven't performed the above technique before you reach the sand, don't fret. A good rule of thumb is to use a pressure of 15 psi or there about's.

Remember though, if you are going to lower your tire pressures, ensure you have a pressure gauge and some means of pumping your tires back up.

As you lower tire pressure, the tire becomes more vulnerable to damage by stoking the sidewall or rolling the tire off the rim. The lower the pressure, the higher the risk. However the gain in traction can be remarkable and may make the difference between becoming hopelessly bogged or simply driving away. The "correct" tire pressure becomes a decision between better traction versus increased risk of tire damage.

In severe cases of bogging, tire pressure can be lowered to a minimum of 40 kPa (6psi), as most tires require at least 6psi to remain seated on the rim while stationary. In almost all situations 10psi should be used as the minimum pressure as 6psi is likely to result in tire damage ie. tires rolled off rims or punctured sidewalls. Speeds should be severely restricted at these low pressures. To minimize tire damage, it is important that these low pressures are only used on sand and tire pressures should be increased if limestone or rocky outcrops are encountered, or when the terrain becomes more firm. Failure to do so will almost certainly result in tire or rim damage.

Sand Driving Techniques

When traveling on sand, you should endeavor to follow in the tire tracks of the vehicle in front as they have already compressed the sand to form a firmer surface than un-traversed ground. Never drive on vegetation as this will destroy it and lead to erosion and environmental damage.

You should avoid rapid changes in speed when accelerating or braking. Braking on sand will cause a mound to build up in front of all wheels and possibly prevent your vehicle from taking off. Rapid acceleration simply digs the wheels in and can actually lead to slower take-off speeds.

Take-off should be performed as smoothly as possible with gear changes done at fairly high revs. Sand driving requires plenty of engine power to get your vehicle "planing" on the sand. It is advisable to use low range as this multiplies the amount of engine torque available and will provide that extra gear if you encounter a particularly soft patch of sand. Check that your tires are pointing straight ahead when taking off to reduce the takeoff effort required.

When stopping on sand, depress the clutch and allow the vehicle to coast to a stop. This will minimize any sand build-up in front of the wheels. If the terrain permits, coast to a stop, rather than braking, with the vehicle pointing downhill as this will aid take-off. Avoid the soft sand at the base of most dunes and gullies when stopping.

When turning, make the turn as wide as possible to reduce the chance of bogging. Your front wheels act more like a rudder in sand and turning too sharp has a similar effect to applying the brakes.

Steep sand dunes can be traversed only straight up or down. If you drive even on a slight angle, the weight transfer is to the downhill side wheels. If the vehicle starts to slip, the downhill wheels tend to dig in and make the angle of the dune even worse, leading to a potential rollover.

If you are traveling straight down a steep dune and the back end starts to slip sideways, it is best to accelerate slightly to try and straighten the vehicle. Never use the brake, as this will cause weight transfer to the front wheels and can increase the back end movement.

If traveling up a dune and you do not get to the top, reverse down the dune in gear, NEVER coast down the dune and NEVER attempt a U turn.

When you return home after a beach trip, it is important to hose down your vehicle to remove all traces of sand and salt. Pay special attention to areas like the mudguards where sand is sprayed around and tends to get trapped. Thoroughly hose underneath your vehicle as well, as there are many nooks and crannies where sand con also get trapped.

Vehicle Recovery in Sand

As soon as you become bogged, avoid the temptation to simply floor the accelerator as this will just make vehicle recovery more difficult. Put the vehicle in reverse and gently try to back along your tracks as they provide a compacted path. When you have reversed a sufficient distance, try going forward again while being careful not dig yourself in. Hopefully you will travel further each time you repeat this technique and eventually be able to slowly pass through a particularly soft section.

If you cannot reverse out of trouble, get out of the vehicle and let your tires down further. A rule of thumb is to drop them by a further 12 psi. Before trying to reverse out, remove the build-up of sand from behind the tires. See if any part of the underside is touching. If it is, clear the sand away to allow the vehicle to reverse out. You may need to try this several times.

If necessary, continue to drop the tire pressures to 10 psi. Also, never underestimate the assistance of your passengers giving a push. As mentioned earlier, tires can be lowered to 6psi in extreme cases, but this should be avoided if other means of vehicle recovery are available.

If you are still stuck and your tires are down to the minimum pressure, you will have to resort to a snatch strap, winching or jacking to extricate yourself. The easiest method is usually by snatch strap, but this relies on another vehicle being present. If you are by yourself you will have to resort to winching (if you have one!) or jacking.

Summary-Sand Driving

lower tire pressures to greatly improve traction and reduce track erosion
drive smoothly with gear changes at high revs
ensure wheels are pointing straight ahead when taking off
avoid the soft sand at the base of dunes and gullies
make turns as wide as possible
ONLY travel straight up or down dunes
follow in others tire tracks to drive on compressed ground
avoid braking by coasting to a stop
do not floor the accelerator if you are bogging down
when bogged, try to reverse on your own tracks
thoroughly hose down your vehicle after a beach trip

VladTepes
15th July 2004, 09:50 AM
BB I hadn't seen this thread before.
Some great tips. I had read these in various places but rarely as concisely and clearly put together as you have done.

Nice job. style_emoticons/<#EMO_DIR#>/biggrin.gif

bigbugga
15th July 2004, 10:13 AM
Originally posted by VladTepes
BB I hadn't seen this thread before.
Some great tips. I had read these in various places but rarely as concisely and clearly put together as you have done.

Nice job. style_emoticons/<#EMO_DIR#>/biggrin.gif

You have been trawling back to some of the first posts I did.

August last year this one.

nige
26th July 2004, 04:14 PM
Excellent info. for uninitiated beach drivers. (and some supposed experienced ones also).
Saw a fully laden Tojo towing a fully laden trailer on my local beach,
up in the soft sand instead of lower down, hit the brakes hard when
he realised he'd just driven straight past the track. He was lucky he
could still open his doors!

Pedro_The_Swift
26th July 2004, 04:23 PM
The balder the tyre the better on sand too,,
though the trip to the beach becomes increasingly difficult :wink:

bigbugga
26th July 2004, 09:00 PM
Originally posted by Pedro_The_Swift
The balder the tyre the better on sand too,,
though the trip to the beach becomes increasingly difficult :wink:

Now there is a can of worms. 8O

I have seen this comment on other forums break out into total WAR as people argue for their veiws.

Some will say Bald is best, while others will say you need a good mud tyre to work well.

Both seem to agree that low presure is still needed.

So good luck Pedro, you opened this can :wink:

fernockulated
26th July 2004, 09:04 PM
:roll: was gunna add my two bobs worth into this one ,but thought against it and decided to leave it in the bank and live off the interest style_emoticons/<#EMO_DIR#>/laugh.gif

bigbugga
26th July 2004, 09:06 PM
Originally posted by fernockulated
:roll: was gunna add my two cents worth into this one ,but thought against it and decided to leave it in the bank and live off the interest style_emoticons/<#EMO_DIR#>/laugh.gif

But if you round it down as you have to now you will end up with 0 cents.


hmmmm seems fitting I think :twisted: :wink:

fernockulated
26th July 2004, 09:12 PM
style_emoticons/<#EMO_DIR#>/laugh.gif sorry ,all your talking reminded me about the price of <span style="font-size:12pt;line-height:100%">inflation</span>

RichardK
26th July 2004, 09:37 PM
Originally posted by bigbugga


Steep sand dunes can be traversed only straight up or down. If you drive even on a slight angle, the weight transfer is to the downhill side wheels. If the vehicle starts to slip, the downhill wheels tend to dig in and make the angle of the dune even worse, leading to a potential rollover.



If traveling up a dune and you do not get to the top, reverse down the dune in gear, NEVER coast down the dune and NEVER attempt a U turn.

Well done BB style_emoticons/<#EMO_DIR#>/biggrin.gif style_emoticons/<#EMO_DIR#>/biggrin.gif

It's amazing how many times I've seen drivers who obviously don't know any better drive up a steep dune and drive a "U" shape 8O 8O

As far as tyres personally I prefer A/T treads for the sand, my experience is that agressive treads dig in too easily, although I've never had "baldies" to try out.

Pedro_The_Swift
27th July 2004, 06:02 PM
just to clarify,,, :wink:

I have done a lot of RACING on sand,,,

even though it wasnt in a 4wd,, the principles are still the same,

no wheelspin, no problem,

wheelspin with no tread,, no problem,

wheelspin with tread,, dig own grave,,,,

come on people,,

what are you're thoughts???

VladTepes
27th July 2004, 06:09 PM
I think I'll have dinner.

Pedro_The_Swift
27th July 2004, 06:18 PM
I thought you could do with a good feed,,,,



but it would slow down th------ ooops,,,,





:wink:

one_iota
27th July 2004, 06:30 PM
"I generally refrain from speech during gustation" Big Dan (Oh Brother Where Art Thou)

Silence is Golden.

one_iota
27th July 2004, 06:38 PM
Ah..... that's better

I draw a sharp breath on seeing TV commercials selling the lesser 4wd being driven down sand dunes at roll over angles 8O

Its no wonder that some people get into trouble on their first day at the beach. They should stay on the black stuff and swim between the flags. style_emoticons/<#EMO_DIR#>/tongue.gif

Pedro_The_Swift
27th July 2004, 06:45 PM
oh, come one one_iota,,
its every ozzys right to drive a brand new 4wd at 100mph along a river or pull a horse float up a mountain,,,

isnt it?

one_iota
27th July 2004, 06:51 PM
Originally posted by Pedro_The_Swift
oh, come one one_iota,,
its every ozzys right to drive a brand new 4wd at 100mph along a river or pull a horse float up a mountain,,,

isnt it?

Yes it is and I'll defend their right to do it largely in the knowledge that they won't or can't. :wink:

0 to 45 degrees in 2 seconds :roll:

Pedro_The_Swift
27th July 2004, 07:13 PM
the dum thing is they can and will,,,

how many toyothingoes rollover on Fraser every year???

DiscoTDI
27th July 2004, 07:47 PM
They used 11 jackaroos to finish one add cause they only lasted a few takes before they fell apart

Saintmud
27th July 2004, 08:08 PM
I enjoyed the article BB, thanks.
The closest thing we have to sand driving down here (Southern Vic) is loose soil or loam. I have come across patches of this loose 'stuff' at the most inopportune times. Usually coming down a steep hill, with tight forrestation, at a bend in the track. The soil builds up on the outer edge and when the front tyres hit it, well lets say its 'interesting'. 8O
The tracks are closed during the winter months and the wind and rain cause many changes by the time they open for the next season, so its 'fun' all over again... :twisted:
Look forward to more.
style_emoticons/<#EMO_DIR#>/smile.gif

VladTepes
27th July 2004, 10:26 PM
Originally posted by Pedro_The_Swift
oh, come one one_iota,,
its every ozzys right to drive a brand new 4wd at 100mph along a river or pull a horse float up a mountain,,,
isnt it?

You forgot "after having been bitten by a Taipan"... style_emoticons/<#EMO_DIR#>/laugh.gif