Jump to content
SAU Community

Recommended Posts

if you want to use the towie/car carrier type ones you posted talk to your trailer builder and see if they can think of a way to mount these in the trailer floor with enough strength in the mounting. it may just require another play underneath to stop it ripping out. or it may just need to be welded on rather than bolted, or both.

PF1NEW_MED.jpg

  • Replies 435
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

TH31J_LRG.jpg

Ideally that's how i'd like to tie down my 600kg vehicle but mounting the d-rings to 2mm floor won't work as it's likely to rip it straight off the frame underneath or atleast try to.

Need to work out a way of mounting the d-rings to the floor, suggestions?

Weld some 6mm+ plate to the underside where you want to mount the d rings

then if you want some extra strength add some 50x6 Equal angle to tie it back to some structural members.

should be a max of 10kg in steel.

yep fully sprung, not unsprung as you said. so are you suggesting your 80% and 50% rule also allows for the extra strain of controlling body roll on top of just holding the weight of the load??? The only way to actually prevent suspension movement would be to pre-tension the straps so much that the suspension is on the bump stops!

quite contrary to your advice of never tieing down from the axles (which you even put in bold!), best practice for securing a vehicle on a trailer is around the tyre/wheel (an unsprung component that does not move in relation to the trailer!) like this cc8.gif and these http://www.uscargocontrol.com/wheelnetscartiedowns-c-47.html as used by car transportes and towies.

but however you tie it down, I think it would be a good idea to at least have straps rated to the weight of the car their holding, particularly if you are tieing to the fully sprung parts of the car that can and do move during transit which puts extra load on your tie downs.

anyway, my advice is go overboard in your tie down ratings rather than trying to use the minimum required. it certainly can't hurt.

The 80/50/20/20 rule is a MINIMUM, and I didn't say it would get rid of body roll, only most of it. Of course the only way to get rid of body roll is to use spring holders on all your suspension and then tie it down. You read too far into not going from the axles, I mean the ACTUAL axles since they were never designed to take that kind of load.

Wheel straps are ok, its just they do nothing to stop body roll so I don't like them if I can tie something down from the body instead. I wouldn't jump to some civilian tow truck drivers way of doing things as it can be extremely dicey, I have seen cars being held by nothing more than the tiny little winch that dragged it up and a ratchet strap over the roof.

thats not bad in the patrol, i have found that i can sit on up to 120 on the flats and straights slowly speeding up and going up the big hills whilst the car will do 100 i go into the slow lane and usually do about 90 trying not to let it kick back another gear.

yep fully sprung, not unsprung as you said. so are you suggesting your 80% and 50% rule also allows for the extra strain of controlling body roll on top of just holding the weight of the load??? The only way to actually prevent suspension movement would be to pre-tension the straps so much that the suspension is on the bump stops!

quite contrary to your advice of never tieing down from the axles (which you even put in bold!), best practice for securing a vehicle on a trailer is around the tyre/wheel (an unsprung component that does not move in relation to the trailer!) like this cc8.gif and these http://www.uscargocontrol.com/wheelnetscartiedowns-c-47.html as used by car transportes and towies.

but however you tie it down, I think it would be a good idea to at least have straps rated to the weight of the car their holding, particularly if you are tieing to the fully sprung parts of the car that can and do move during transit which puts extra load on your tie downs.

anyway, my advice is go overboard in your tie down ratings rather than trying to use the minimum required. it certainly can't hurt.

If you want to eliminate body roll completely (even though its not much of an issue on racecars) run transport blocks (as mentioned). I think you will find that most major vehicle manufacturers will run either spring retaining blocks or a series or spacers blocks when shipping vehicles from the factory.

I don't think suspension movement is an issue either. if anything, it would probalby help dampen the inertia of the trailer making it more stable. as for body roll being a problem - hardly likely on race cars as you say. I've towed a few rally cars which are much higher and softer setups than track/race cars and even a lifted 4WD a couple of times secured by unsprung components that don't move relative to the trailer so the body and suspension of the towed vehicle are free to move and I've never encountered any instability problems with my trailer.

Well you stick to ifs and assumptions and I'll go with my 5 years of towing everything from box trailers to 126 ton worth of tanks (thats 2 tanks on A-frame behind mine)

Not going from the body leaves the load free to move around on its suspension, even when tied down properly at the wheels the movement from the car can act against the movement of the trailer. This movement can amplify to the point that your trailer has a huge influence on the tow vehicles handling which if nothing else is dead set dangerous. If you want to help dampen the inertia of the trailer (as you put it) then set up your tow vehicle properly :(

Tying down from the body and having the trailer and load move as one is much more stable/safer for both the trailer and tow vehicle.

A quick example was the last time my car was a on a tilt bed, the driver said "wow you can barely feel the car back there on the tray, how stiff is it?" I replied "full cage and 10kg/mm springs and stiff dampers all around" This is the kind of thing you are after when towing, not being able to feel the load ;)

My car was tied down by wheel straps, but the suspension did a lot to stop body roll as was my intention for drifting :)

I guess I'm almost repeating myself now but yes if the load you are tying down is very stiff as it is, then not much need for going from the body. For long distances though as Trent said, it will get really annoying when you can feel the car at every little bump and turn.

Edited by mitch_SR32

Picked up a new tow vehicle today, well business vehicle but it will tow my trailer/aussie car much better than my 9yo Hiace (64kw).

Just a 2004 Hino Dutro 5000 4.6L 114kw 430nm. Has a 3.9m pan which is large enuff to fit my aussie car but too much hassle getting the damn thing in there so i'll just use the pan to bring every tool I own to the track, a set of tyres and my sleeping bag :P

truck2.jpg

Well you stick to ifs and assumptions and I'll go with my 5 years of towing everything from box trailers to 126 ton worth of tanks (thats 2 tanks on A-frame behind mine)

Not going from the body leaves the load free to move around on its suspension, even when tied down properly at the wheels the movement from the car can act against the movement of the trailer. This movement can amplify to the point that your trailer has a huge influence on the tow vehicles handling which if nothing else is dead set dangerous. If you want to help dampen the inertia of the trailer (as you put it) then set up your tow vehicle properly :P

Tying down from the body and having the trailer and load move as one is much more stable/safer for both the trailer and tow vehicle.

A quick example was the last time my car was a on a tilt bed, the driver said "wow you can barely feel the car back there on the tray, how stiff is it?" I replied "full cage and 10kg/mm springs and stiff dampers all around" This is the kind of thing you are after when towing, not being able to feel the load :ermm:

My car was tied down by wheel straps, but the suspension did a lot to stop body roll as was my intention for drifting ;)

I guess I'm almost repeating myself now but yes if the load you are tying down is very stiff as it is, then not much need for going from the body. For long distances though as Trent said, it will get really annoying when you can feel the car at every little bump and turn.

bah, I'm tired of being nice in the face of your condescending attitude... as much as I'm sure it will surprise you to find you don't know everything about towing, some car carriers don't have springs at all and work on the priciple of using the vehicle's suspension to dampen the combination. Its a proven principle, not ifs and assumptions.

you stick to your box trailers and tank towing experience. I've towed box trailers too but I struggle to find any relevance of that to this discussion, but I guess I must be missing something blindingly obvious (yes, that's sarcasm). And I'll bet you dollars to cents that these defence force tanks you keep name dropping as proof you know better aren't being held at a single point front and rear by ratchet straps as per your advice here, but completely secured by tensioned chains preventing any suspension movement and the resultant problems (which I've covered before but will get to again here too). I'll stick to my experience towing all sorts of cars over all sorts of roads up to a couple of thousand kilometers in a single round-trip, complete with blowouts at higway speeds both on the rear of the 4WD tow vehicle and the trailer itself, without once feeling any sort of movement in the load being carried when secured to unsprung components even in that scenario, or as previously mentioned when towing lifted high Cg 4WDs even up and down mountains and over rough dirt roads. As I said before, you wouldn't even know there was a load on the back of the patrol except for it being even slower than normal.

In fact that the only time I ever felt a load on the trailer was when it was held down from the body! You felt a harsh sudden jolt every time the strap was jerked tight. That was how I learnt the error of securing a vehicle from a fully sprung component when i started towing cars. It makes perfect sense - any movement of the suspension when tied down from the body will loosen then suddenly tighten the straps. The suspension WILL move downwards when the trailer hits a bump unless you have done something to prevent that from happening. You can't argue with Newton's equal and opposite reactions. If the trailer moves up over a bump, the car's suspension will compress. When the suspension compresses the fully sprung part sof the car move down. When the fully sprung parts of the car move down, the straps holding them loosen. When the straps loosen, the load is free to move. When the straps tighten as the suspension rebounds and/or the load has moved to the extent permitted by the slack straps, they are being shock loaded. When the strap is shock loaded it might loosen gradually or even fail completely, and you didn't recommend using a safety chain did you? anyway, the shorter the length of tensioned strap to the fully sprung component the worse the effects will be. if the length of tensioned webbing is long enough compared to the suspenion movement, you might be totally oblivious to it going on and suffer no ill effects from it, but it is nonetheless happening to whatever degree. So if you must tie down to the body or any fully sprung component (like a K-frame!) make the straps as long as possible would be my advice. The X pattern someone else mentioned to the K frame would be a good example of getting the straps as long as possible to mitigate this inherent problem of tieing down a moving component of the vehicle.

compare that real issue with your method to what I can gather of your objections to my securing advice: that I like to over-rate the straps I use for no good reason other than a bit of a margin for safety - shocking mistake isn't it! And this supposed body roll probem that you seem to think race cars (which is what we are talking about towing) have at legal road speeds combined with the cornering forces generated by the wonderful chassis dynamics of the tow car and trailer when towing these wobbly racecars. I know you drifter think racecars use soft setups, but really...

so, unless you have any sensible points about problems with securing a vehicle by unsprung components I won't bother rising to any more of your "I've towed tanks and I'm right" posts.

1: I said everything FROM box trailers to tanks meaning I have put a lot of things on trailers of all shapes and sizes and sometimes not even vehicles.

2: You were the one who used words like if and probably so thats how I read it.

3: I never said using over rated straps was a bad idea, infact I said I encourage it and recommend it to people. Just going too far with the rating can sometimes do more harm than good depending on what and where you tie down.

4: I don't believe I said race cars have soft setups, I was trying to keep it general throughout my posts.

5: I did think about going into the science behind tie town methods from different parts of the car but I don't have any photos or a program to draw up where straps can/cannot go. In that light I do agree with you saying that you need longer straps when going from the body. Your point about the safety chain, I know that its all part of a 'by the book' tie down process but honestly how many people INCLUDING qualified civi towies do you see doing it? I know what shock loading is and what it can do but thats why I posted up when to check your load after tying it down. Those checks will help you get the tension right once the load has settled on the trailer and should (nothing tied down is ever 100% stable save for twist locks maybe) stop a lot of the movement that would loosen a strap.

All this aside I wasn't trying to be condescending, but I have always come off that way and I guess it is why I sit here typing this out instead of going out with friends.

Edited by mitch_SR32

Ben, that looks like a good upgrade. and you are right, just tow the trailer off it and use the space to carry gear. Not worth the effort to get ramps or a lift to get the car in, and if you do it will severly compromise it's day to day usefulness

Harry and Mitch....can you guys let it go....

John - why do you want to go back to open? lighter or some other reason?

bah, I'm tired of being nice in the face of your condescending attitude... as much as I'm sure it will surprise you to find you don't know everything about towing, some car carriers don't have springs at all and work on the priciple of using the vehicle's suspension to dampen the combination. Its a proven principle, not ifs and assumptions.

you stick to your box trailers and tank towing experience. I've towed box trailers too but I struggle to find any relevance of that to this discussion, but I guess I must be missing something blindingly obvious (yes, that's sarcasm). And I'll bet you dollars to cents that these defence force tanks you keep name dropping as proof you know better aren't being held at a single point front and rear by ratchet straps as per your advice here, but completely secured by tensioned chains preventing any suspension movement and the resultant problems (which I've covered before but will get to again here too). I'll stick to my experience towing all sorts of cars over all sorts of roads up to a couple of thousand kilometers in a single round-trip, complete with blowouts at higway speeds both on the rear of the 4WD tow vehicle and the trailer itself, without once feeling any sort of movement in the load being carried when secured to unsprung components even in that scenario, or as previously mentioned when towing lifted high Cg 4WDs even up and down mountains and over rough dirt roads. As I said before, you wouldn't even know there was a load on the back of the patrol except for it being even slower than normal.

In fact that the only time I ever felt a load on the trailer was when it was held down from the body! You felt a harsh sudden jolt every time the strap was jerked tight. That was how I learnt the error of securing a vehicle from a fully sprung component when i started towing cars. It makes perfect sense - any movement of the suspension when tied down from the body will loosen then suddenly tighten the straps. The suspension WILL move downwards when the trailer hits a bump unless you have done something to prevent that from happening. You can't argue with Newton's equal and opposite reactions. If the trailer moves up over a bump, the car's suspension will compress. When the suspension compresses the fully sprung part sof the car move down. When the fully sprung parts of the car move down, the straps holding them loosen. When the straps loosen, the load is free to move. When the straps tighten as the suspension rebounds and/or the load has moved to the extent permitted by the slack straps, they are being shock loaded. When the strap is shock loaded it might loosen gradually or even fail completely, and you didn't recommend using a safety chain did you? anyway, the shorter the length of tensioned strap to the fully sprung component the worse the effects will be. if the length of tensioned webbing is long enough compared to the suspenion movement, you might be totally oblivious to it going on and suffer no ill effects from it, but it is nonetheless happening to whatever degree. So if you must tie down to the body or any fully sprung component (like a K-frame!) make the straps as long as possible would be my advice. The X pattern someone else mentioned to the K frame would be a good example of getting the straps as long as possible to mitigate this inherent problem of tieing down a moving component of the vehicle.

compare that real issue with your method to what I can gather of your objections to my securing advice: that I like to over-rate the straps I use for no good reason other than a bit of a margin for safety - shocking mistake isn't it! And this supposed body roll probem that you seem to think race cars (which is what we are talking about towing) have at legal road speeds combined with the cornering forces generated by the wonderful chassis dynamics of the tow car and trailer when towing these wobbly racecars. I know you drifter think racecars use soft setups, but really...

so, unless you have any sensible points about problems with securing a vehicle by unsprung components I won't bother rising to any more of your "I've towed tanks and I'm right" posts.

C'mon Harry.......breathe in........... and out..........now relax.... No need to get your knickers in a knot, leave the knots for tying down on the trailer :(

looks like it was already over to me. I'd already said I wouldn't replying on that point anymore and it looks like I misinterpreted Mitch anyway, so apologies for my condescending/narky remarks Mitch.

I'm looking for a new trailer too. I stupidly sold mine to a mate just recently after selling my Datto track car, but I now have another track only car on the way... maybe he'll sell it back to me.

Hey Duncan

I have used the MRT to mainly move my girl three times over the last 12 months lol and she now uses it to store her stuff in hahaha

I bought it when I was planning on making a comeback to IPRA a number of years ago. It has an annexe as well, very flash!!!

The only motorsport car that I actually own now is my Grunter Datto 1600 rallycar. I hardly have time to use the Datto, let alone the trailer. It is complete overkill for me now, as I pretty have been driving other peoples cars for the last 11 years.

So I still want to have a trailer, as I have always had one for the last god knows how many years............just a 4 wheel open one will do me.

I will probably advertise it on MY105 and just buy a new open one if knowbody is interested. I will put it on a few forums first though ;)

It will fit a GTR :action-smiley-069:

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...