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Posts posted by Daan
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Well well, touched a nerve or what? Always interesting when I start a debate about regulations and actually mention facts, people go of course by saying things like:
-It worked in the past
-If you dont like it dont turn up
-There are still enough people turning up
-Have you ever done any events
-Have we met
My point is, using boothy and saley as an example, that boothys truck is class 3 with 35 inch tyres, where as saleys truck runs 40's, weighs halve of boothys and is class 2.
If people dont mind that, fair enough, but I dont think it is right myself.
On the plus side, the awdc is making an effort to put things in classes, rather than ban them, like many other organisers do at the moment. So why come up with rules that dont actually create a level playing field?
I do say this , that on 1 event, ladoga, I have witnessed for the first time in my life a level playing field on the event. I would love to see that happening here.
Also, something that seems possible in that part of the world is that organisers are willing to talk to each other, and the result is that organisers have one set of rules that is generally used. This saves an awfull lot of grief, because you dont have to change the spec of your car for every other event.
The reason for me to comment on this without actually turning up on an event is that if the awdc club rules would make sense, some other organisers might actually adapt them, and who knows we all live in harmony ever after....
This is a subject close to my hart and having seen several different types of motorsport regulations, they always are based on the factors that affect performance. In our case, that is tyre size. So my point is that it would be better to base regulations on what makes the car perform better, which is mainly tyres.
Hope to meet you face to face one day, Chris.
Daan
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Very interesting build!
Daan
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yeah but in the le mans 24 hour race all classes run at the same time on the same track
But they arent in the same class.
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Having spoken to a number of competitors most were against the system and, as James says, felt it penalised vehicle development.
On this basis and the fact that it would extremely hard to police effectively we have decided to keep the existing class structure which has served us well for the last 6 years.
So you still believe that a formula one should be on the same grid as a touring car? The fact that Saley is in the same class as a challenge 90 shows that your regulations are fundamentaly flawed.
Daan
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Lifting the panhard rod relative to the axle will raise the roll centre (the point around which the body rolls compared to the axles) In theory, the closer the roll centre is to the centre of gravity, the less the body will roll as the lever arm of the body weight is reduced. In practice though I would think that by raising the roll centre, as in right hand pick, you will increase the lever acting on the springs during roll and would need a stiffer spring to reduce roll.
It is the other way round, you decrease the lever for the cofg to work on and therefore the roll will reduce, like I mentioned in my previous post.
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The whole articulation thing is a double edged sword - to a much greater extent than I realised when I started building my 'buggy'.
I like many had assumed that supple long travel suspension was best - and built something where you could lift one tyre 52" off the ground before any other lifted.
In a traditional cross axle - this works great. However, people setting up winch challenges tend not to make them such that with equal front & rear travel, the vehicle will stay level - they often tend to be traversing a side slope with cross axle.
Why is this a problem? Because most of the vehicle weight is on the down-hill rear wheel. The suspension fully compresses and you quickly get in to a situation where that wheel is tucked under the vehicle to the extent that the vehicle can roll over that wheel and topple.
It'a axtually the same thing as happens to 3 wheelers if you corner too fast - because there is no front wheel to push the diagonally opposite rear wheel down, it lifts and rolls.
In conclusion, I think that the suspension, even if it has loads of travel, needs to be stiff enough to hold the diagonally opposite wheel on the ground.
How stiff is this?
It depends on a number of factors including the wheelbase and track of the vehicle, it's weight and the steepness of slope you want to climb.
Likewise on a side slope, the vehicle leaning towards the down hill side can topple it earlier than you might expect - and in this case you have two springs pushing you back up.
Calculating the spring rates etc is going to be difficult - so maybe better to go for a trial & error solution. For that reason more than any, I favour the Fox Air Shox as you can set them up however you want.
The bottom line is that as you increase the travel, the increase becomes less & less worthwhile because you start to loose stability on slopes.
Using a small winch to pull up the centre of the axle might work well - as it will stiffen up the suspension as well as lowering the G of G, improving the slope stability.
Si
All true, but one more factor is important here: roll centre position. Basically, this is the axis over which the body pivots. The higher this point is, the less body roll you have, to the point that if your roll centre is at the same hight as the centre of gravity, there wont be any body roll at all. Of course there are other problems you need to consider, beacuse the ride would be very strange with this setup, but it is certainly a factor to consider. Also the lower the centre of gravity the less roll, as you mentioned.
Daan
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My major concern on the whole idea is using Landrover axles. They're a weak out of date design and don't have too many options for modifying and upgrading (not like a Dana 44 or 60 for example). I know there is an obvious market in the UK for an easy Landrover upgrade, but I think maybe looking at a complete axle solution, like Spidertrax may be a better way forward and widen the appeal to the European, US and Oz markets.
That is all true, but spidertrax only represents about 1 percent of all ofroaders, whereas landrover axles would represent at least 50% I would have thought, even world wide.
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All true whats said above, however, if you manage to source a standard available set of gears that is massproduced and adapt this, there might be mileage in the idea.
Daan
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pm sent.
Daan
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The facts are that the Tuff trophy was held at the end of July and the RFC was at the beginning of December the same year which only gave whoever was going to go 4 months- 16 weeks to prepare a car to a good enough standard to compete in a high profile event, get together funds, as the prize was only for entry, and to ship the car there!!!
We had long discussions at the end of the event and when we returned with all parties concerned, including Adrain and Dan and every agreed that there just wasn't enough time!! We spoke to the organisers of the event and proposed that if he could postpone the entry to 2010 then we would bring the winning team + another 2 or 3 teams from the UK, fully paying. He replied saying that the prize had been put up because 2009 was a recession year and that is why they were trying to promote the event as entries were low. So we left it at that.
This is the facts and for those of you who don't agree you might want to have a little think!!!!
Lucy
Ok, always good to know the facts. As I stated before, the price is worth having and if you ever think of doing it, now is the time to start organizing to go in 2011. dont start thinking about it in july, because it gets very tight. Also bear in mind that the ship takes 3 weeks to travel from southampton docks to arrive in KL (if it ever gets there
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Daan
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I dont think it will go. the td5 pto is longer, to clear the crossmember IIRC.
Daan
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Adrian,my point was and is that if you want to do it, you have to plan for it to go as a priority. You can always compete in the tuff trophy event to win the free entry along the way, a 1k saving is worth having, but as history has shown you have to start preparing way before that and prepare to take the full financial hit because you can never count on what other people do.
Let me know if you decide to go.
Daan
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I personally do not believe for a moment the prize will motivate anyone to do it. The commitment required to compete in the RFC is very great, and whether the entry is free wont be a deal breaker or maker.
Talking numbers: you are going to spend at least 5k doing it, and having free entry saves you 1k. Do all of a sudden hordes of people think were doing it? no.
It is a bit of a pet hate of me, that people say: were doing it without really thinking it through. In the beginning of 2003, there were 6 teams going. There was a plan to have 2 40 feet containers loaded up with 6 cars, and the whole thing would actually be quite affordable. The week before the ship was about to leave, there were me and Bucky left who were going. Then Bucky decided he couldnt make it, and yes there we were: me and my mate mark in our landy were going.
I do wonder whether all these people were ever really planning to go?
It is a big undertaking and I made the decission with christmas 2002, to go in november 2003. This gave me 10 months to organize it (I had to prepare the car as well). It happenned eventually, but in the end it was still the usual chaos (to get ready).
Still, It is by far the best thing I ever did, and all uk events put together quite frankly cant hold a candle to it, and as a result I can say: it was worth every penny.
Daan
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No need to test this, I am running detroit locking diffs, and if there is a difference in tyre pressures left to right (it only needs to be 2 psi difference), it wont drive in a straight line. That should tell something.
Daan
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I reckon speed reduces with less pressure, because your effective diameter gets smaller. Your right that the circumference dont change, but what happens is that there is effectively wheelspin at the two points where the tyre goes from round to flat. This gives a lot of heat and tyre wear and that is why you shouldn't run with your tyres deflated at any decent speed on the road.
There is now a trend for energy tyres, which run with more pressure than we used to, which obviously achieves better rolling resistance. So basically, the more pressure the better for rolling ressistance.
I reckon, anyway.
Daan
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I think the rear diff on an isuzu is centred, which gives a problem with your axle setup, because it is offset. This will give large propshaft angles, especially with the lift. If you look on ebay, you will however regularly find isuzu engines complete with a landrover gearbox, already converted.
daan
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With regards to the fusable stubaxle and fatigue strangth: It would be much better to waist the stub shaft over the full length between the splines, rather than just the groove. This would give it much more flexibility in the shaft and would represent much less shockloads on the whole front drivetrain, while still being the weakest point.
Daan
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TDI all the way. It is cheap to put in, and wil have plenty of poke, espesially if you put a bigger intercooler in. As long as the gearing is right, it will run very well. With regards to cost, I bet that the actual cost for any conversion is at least as much as the engine itself, but the biggest cost comes when you come to sell it; a tdi will always fetch good money, where as a converted car is more a case what some individual think its worth, if anything.
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As that link shows, yes it explains grade 8, but no, not available in BSF. To answer your original question tuko, I think, looking from the picture, that you are ok on the length as is. I also used schnorr washers under the boltheads, since there was enough length, but it isn't strictly needed I reckon. Lock tab washers was something else I tried, but they dont work with a pegged diff.
Hmm, memories of desperate times.
Daan
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I got my bolts from this lot:
They are good quality but I dont think they are any better than 8.8. The length I used, I think was 1.25 inch, but please double check this.
The problem I found is that proper high tension in this treadform is unobtanium. As I mentioned, capheads do exist, but dont fit. In the end, I loctited the diff, spacer and ringgear together and it has been reliable ever since using the strongest loctite known to man (cant remember the number). after loctiting, the bolts dont serve any purpose and, in theory, could be left out. If you ever need to replace a ringgear, it involves making a campfire to split them again.
Desperate times, desperate measures...
Daan
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Aren't these bsf bolts? In which case you are in a bit of a situation; I never managed to find high tension ones for my KAM ringgears. The only ones available are capheads, but they foul the casing.
Daan
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Wellits an angle, which changes when you lift it, so with your sin, cos and tan knowledge gained at school, I am sure you can work it out!
There are more options: I run a standard rear prop on the back of my hybrid, and a defender 90 rear at the front. Not sure how would work out on your setup, I have used a lt230 box and the wheelbase of 89". Hardly any lift at all.
You obviously can gain a bit of length with your extended joke idea (never realised it would fit), although that doesnt work on a defender prop.
daan
mig welder repair
in Tools and Fabrication
Posted
Hi, As it says, my mig welder stopped working (triggering only activates the gas release solenoid, but no wirefeed or current).
I cant see anything obvious broken or burnt out so a bit out of my depth here. Is there anyone good for welder repairs round oxfordshire area? The type is an Oxford 181 turbo welder.
Daan