biggoolies
Adventurer
Oh I see at the beginning you calculated 3km/l about 7mpg US
Merkabah: MB 2626 AK 6x6 tipper to expedition truck conversion
- Thread starter pairospam
- Start date
Having just read the thread from the beginning, I must say this is one of the most impressive and inspiring builds I've read. You saw what other people couldn't when looking at the poor neglected thing at the beginning. I find myself irrationally happy for Merkabah, getting plucked from a bleak life of getting worked to death to becoming this incredible machine with a whole new future.
Really looking forward to more.
Really looking forward to more.
Wazak
Member
I don't know about anyone else but I can only see the dirt road suspension test photoFrame flex tests.
Dirt road air suspension tests.
Works. And wow!
Wazak
Member
I love the flexometer.
Great photos of your flex test.
Sitec
Adventurer
Looking fantastic... Liking the fact that you are taking the time to work out the flex and mounting... One thing to remember.... Lots of people make 3 or 4 point mounting systems, but make the mistake of sitting it all above the chassis rails (because its easy to do and logical). Don't make the same mistake, as 6x6 flex is even more extreme than 4x4 due to the rear spring setup. Make sure the central pivot points are mounted within the chassis as this is where the pivot point is. Attached is a pic from Steve's book 'build your own overland camper'. This shows why the pivot point must be between the chassis rails. 
Looking forward to the next stage of your build!
Looking forward to the next stage of your build!
Hi, Sitec:
Well, actually it is a little more complicated than that, as it is not said that the axial torsion point of the frame is at the middle of the framerails, as Steven proposes. Though he is near.
That damn spot is somewhere in between the superior half of the framerail and the top of it, and it may change depending on a series of factors as the location of crossmembers, the size, shape and structure of the console of the bogie, the shape of the framerails, the lenght, etc.
I came to the conclusion that I have to explore and find the proper height of the axial flex point myself, as by no means anybody can for sure tell you where it is. And I am sure I am going to find out that the front pivot is different from the rear one, and I need to get it by the milimeter.
This is why this whole business is so amusing.
Kind regards.
Pairoa
Well, actually it is a little more complicated than that, as it is not said that the axial torsion point of the frame is at the middle of the framerails, as Steven proposes. Though he is near.
That damn spot is somewhere in between the superior half of the framerail and the top of it, and it may change depending on a series of factors as the location of crossmembers, the size, shape and structure of the console of the bogie, the shape of the framerails, the lenght, etc.
I came to the conclusion that I have to explore and find the proper height of the axial flex point myself, as by no means anybody can for sure tell you where it is. And I am sure I am going to find out that the front pivot is different from the rear one, and I need to get it by the milimeter.
This is why this whole business is so amusing.
Kind regards.
Pairoa
Sitec
Adventurer
Hi Paiora.
This is good information. I had sort of assumed that the center of the rails would be thee central twist point... but going on what you are suggesting (which makes sense ) I too will be carrying out a 'frame twist test' like you have. I'd also be interested to see what point you settle on for your pivots. Following with interest!
Cheers, Simon.
This is good information. I had sort of assumed that the center of the rails would be thee central twist point... but going on what you are suggesting (which makes sense
) I too will be carrying out a 'frame twist test' like you have. I'd also be interested to see what point you settle on for your pivots. Following with interest! Cheers, Simon.
Sitec
Adventurer
Hi again Paiora.
Did you have any more progress on your chassis twist tests and where the center line is sitting on your truck? I'm at that point now so interested in what you have found. I've decided to go for it and start building my 4 point system. I believe that the chassis 'twist line center' is roughly in the middle of the C sections (if you factor in the areas where the chassis depth is thinner at the rear for springs and axles etc, then this line is just above center). As the gearbox sits where the front pivot mount needs to sit, I am going to have my two fixed outer mounting points at the front of the body and the two central pivots further back (one mid way and one at the rear). This helps leep the front of the body and rear of the cab in a similar position making the crawl thru simple... With this system in mind I'm now thinking of hanging the rear lockers of the body and not mounting them to the chassis, as the chassis will have a lot of movement in relation to the body. This means The only thing at the rear that will get close to the body under twist is the tyres. I still plan to have a way of restricting twist/roll when on the highway... Below is a pic of the 60mm hole I'm planning on using for the front two outer points of my 4 point system. It is about 600mm back from the front of the body, and is a double plate hole as the spring hanger is very close.
Did you have any more progress on your chassis twist tests and where the center line is sitting on your truck? I'm at that point now so interested in what you have found. I've decided to go for it and start building my 4 point system. I believe that the chassis 'twist line center' is roughly in the middle of the C sections (if you factor in the areas where the chassis depth is thinner at the rear for springs and axles etc, then this line is just above center). As the gearbox sits where the front pivot mount needs to sit, I am going to have my two fixed outer mounting points at the front of the body and the two central pivots further back (one mid way and one at the rear). This helps leep the front of the body and rear of the cab in a similar position making the crawl thru simple... With this system in mind I'm now thinking of hanging the rear lockers of the body and not mounting them to the chassis, as the chassis will have a lot of movement in relation to the body. This means The only thing at the rear that will get close to the body under twist is the tyres. I still plan to have a way of restricting twist/roll when on the highway... Below is a pic of the 60mm hole I'm planning on using for the front two outer points of my 4 point system. It is about 600mm back from the front of the body, and is a double plate hole as the spring hanger is very close.
Sitec
Adventurer
Here's a quick cross section sketch of how I plan to do the mount. I think this setup will be fine on my 4x4 truck as the body is only 6m long... In theory it would work on your 6x6 too as the rear pivot on yours only needs to be between the two rear axles. The tail of your chassis could be chopped, and the body hung over the rear with a lower section... Thoughts??
Sorry for the late reply, Sitec. Things have been a little complicated lastly in my country, and I have completely forgotten this thread as the main story goes on another site.
I think that you have done good. There is not just one way to go, and yours is the most appropriate for you. It looks pretty tough too.
More to come when possible.
Ah, and I have never stopped working on the truck.
Cheers.
Pairoa
I think that you have done good. There is not just one way to go, and yours is the most appropriate for you. It looks pretty tough too.
More to come when possible.
Ah, and I have never stopped working on the truck.
Cheers.
Pairoa
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