Water & Batteries... in front of wheel wells or behind?

[TheHubbardBus]

Planning our conversion & trying to determine an ideal location for the heavy stuff.

At present, it looks like we should be able to put the batteries on one side of the bus, and our fresh/grey water tank on the other. Both will weigh close to the same (when full of water), so side-to-side weight distribution should be gtg.

If I placed these two items on either side, what would be the best lengthwise orientation... directly behind the rear wheel-wells, or directly in front of them? (those are the two options I think I'll have). And why?

FYI - dognose bus. 6 windows min to 8 windows max.

 

[ol trunt]

Glad to see you are considering weight distribution. To come up with the best arrangement you'll need to know the empty weight on both the left side, right side and front and rear axles. You will want to know max allowable weight on front and rear axles and not exceed them. Any weight you put behind the rear axle (or in front of the front axle) will be carried by those respective axles and will have a lever arm effect on the opposite axle--think sissy bars to help keep the front wheels of a dragster on the ground. With that info at hand you will be able to design and build a very practical and safe Skoolie.
Jack

 

[TheHubbardBus]

Thanks so much, Trunt!


Do you (or anyone else) know if truck weigh stations will allow you to use their scales to determine these figures (aside from the max-weight specs which I already know).



I can do the math to figure out approximately how much weight will be carried by either axle depending on the fore-aft location of these components. But what I don't know is what a good weight distribution between front & rear axle would be. 50/50? 40/60? More? I'd think you'd want to bias the rear a bit for traction, but it's the actual amount I have no clue about.



Love your ride, BTW

 

[Native-SKO]

Look into truck fuel stations ... the QT's, Pilot's, Fuel City's, etc.


So far I have not found one that measures left and right just front and rear axles.

 

[solvo]

Personally I would not put them behind the wheel wells unless you’re planning on protecting them from road debris. Since you’ll be continually transferring freshwater to gray water the weight distribution from side to side would be very tricky. If possible hanging them from the frame in the center of the bus between the axles would be ideal. 1 gallon of water weighs 8 pounds 100 gallons would be 800 pounds. With that kind of weight you would want it in the center of your bus which would also help with the way the bus rides down the road.

 

[TheHubbardBus]

Thanks for the info, Native. We'll do that!

Solvo, our tentative plan is to house the fresh water tank inside, and the grey water tank directly below it outside. We won't have a black tank (compositing toilet), so the majority of our water weight, sans what's lost to drinking, will be in the same location. The batteries on the other side of the bus would be the balance.

Alternatively, I'm considering 2 fresh water tanks on opposite sides of the bus (inside), with a single greywater centered between the frame rails. In that case I need to balance the battery bank on its own.

I hadn't thought about road debris concerning the grey water tank, so good call there! I did plan on welding up a protective cage/mount, so I'll make sure it incorporates that protection if necessary.

Anticipating a short(er) bus, though not sure yet, so space is at a premium. So far, unfortunately, I've found it very difficult to find a place for fresh water forward of the rear axle. I'll keep looking. But if I do have to put it behind the rear wheel-wells, it will be right behind them, with tall tank rather than long & flat to keep the weight as close to the axle as possible.

 

[ol trunt]

THB, I've found all sorts of useful info at this site: GM UPFITTER - Body Builder Manuals. While it is specifically aimed at GM stuff, you'll find lots of transferable facts about weight distribution for medium duty (under 26,000#) trucks. Just choose a model year and search the General information table of contents for weights etc.
Jack

 

[TheHubbardBus]

Sweet Jack. Muchas Gracias.

 

[HazMatt-SKO]

Don't know from whence it hailed; but the seller of my rig included a fresh-H2O tank, maybe 25-30 gallon, that is sized to fit snugly right up behind the start battery box...
Yet to install, so if yas need a snapshot, give with a holla.

 

[TheHubbardBus]

Thanks so much, Matt. But won't be necessary. Think we've got things tentatively figured out (fingers crossed).

With a bit of concession regarding our target floor plan, it looks like we can get the bulk of the vehicle weight - discounting the powertrain & shell - evenly balanced in regards to the rear axle. In our new plan, I'm putting the battery bank directly over the rear axle, the water tanks directly behind it, and most of the other heavy items spread out in front of it. Taking into account just about every item besides the engine, powertrain, and shell, I've got 2/5 of the mass behind the rear axle, 2/5 in front of it, and 1/5 directly over it. And what is behind the axle - mostly the water - is something we have the option of reducing significantly during long over-the-road stints to either improve ride quality/traction/road-holding and/or improve mileage.

Plus - side-to-side - I've got us down to <50# difference. Pretty much took all weekend to figure this stuff out, but I'm feeling pretty good about our plan at the moment. We'll see how it translates to real life soon (lol).

 

[HazMatt-SKO]

Gotta reckon the engineers & designers contrived to keep the intrinsic machanicals in balance, not unlike a boat's keel ballast, so prolly needn't figure in the cyphering...
Tho unlikely they considered what we unbalanced folx would later deign to effect upon their designs...
Assiduous fore/aft, port & starboard loading in balance shouldn't impact stability or handling.
Of concern is the house bank being inside, tho you doubtlessly have concocted a scheme to allow them to safely vent to the exterior.
In which case, no need to get the lead out.

 

[TheHubbardBus]

Yep... I'm good to go on the venting. Going to use AGMs, as well as vent the compartments to the outside in the case the pressure buttons get pushed. I wanted them inside if possible to keep their temps in a happy range. Plus, when I'm alone, I plan to open up the cabinets and make Tim Allen "more power" grunt sounds.


Feel ya on the leeway, but my OCD wouldn't have it any other way :biggrin:

 

[HazMatt-SKO]

Case like this, a little OCD is hopefully enough. I thought AGMs handle cold pretty well, not that freezing temps are on the menu, not outside of the fridge, anyway...
When waiting fills, I'd very much like to see your battery box. Or direct me to where it may already be posted, por favor
Not digging my "current" available options, tho still miles away from starting my batt bank.
In closing, I'd just like to add,
UNH!!!

 

[TheHubbardBus]

:biggrin:

I'd very much like to see my battery box too, Matt! Currently in the planning stages here, unfortunately.

But I absolutely, positively will share as soon as this project goes hot. I'm pretty amped just thinking about it. I've been flooded with ideas. I think our bus has quite a lot of potential, so long as I don't encounter undue resistance from the wife. After all these years together, however, I'm able to gauge her pretty well.

Anyway, gotta go get some meditation time in. Catch you later...

'Ohm'
'Ohm'
'Ohm'

 

[CaptSquid]

1 gallon of FRESH water weighs 8.36 pounds 100 gallons would be 836 pounds.

 

[TheHubbardBus]

1 gallon of FRESH water weighs 8.36 pounds 100 gallons would be 836 pounds.

Understood. And the batteries weigh nearly another 800.

I'll be throwing out 16 children to make up for the difference.

Or 8 if they eat like me :biggrin:

 

[HazMatt-SKO]

*owwie*
Yanno, I'm certain you HAD to miss an electrical pun in there, somewhere.

[emoji3]

I'd very much like to see my battery box too, Matt! Currently in the planning stages here, unfortunately.

But I absolutely, positively will share as soon as this project goes hot. I'm pretty amped just thinking about it. I've been flooded with ideas. I think our bus has quite a lot of potential, so long as I don't encounter undue resistance from the wife. After all these years together, however, I'm able to gauge her pretty well.

Anyway, gotta go get some meditation time in. Catch you later...

'Ohm'
'Ohm'
'Ohm'

But after maybe 3.5 hours of interrupted sleep in the friggin elevated heat n humidity last night, the light bulb just ain't coming on for me.
Wattever I missed, gonna have to take a pas(quale)

 

[Mark_In_MA]

Thanks so much, Matt. But won't be necessary. Think we've got things tentatively figured out (fingers crossed).

With a bit of concession regarding our target floor plan, it looks like we can get the bulk of the vehicle weight - discounting the powertrain & shell - evenly balanced in regards to the rear axle. In our new plan, I'm putting the battery bank directly over the rear axle, the water tanks directly behind it, and most of the other heavy items spread out in front of it. Taking into account just about every item besides the engine, powertrain, and shell, I've got 2/5 of the mass behind the rear axle, 2/5 in front of it, and 1/5 directly over it. And what is behind the axle - mostly the water - is something we have the option of reducing significantly during long over-the-road stints to either improve ride quality/traction/road-holding and/or improve mileage.

Plus - side-to-side - I've got us down to <50# difference. Pretty much took all weekend to figure this stuff out, but I'm feeling pretty good about our plan at the moment. We'll see how it translates to real life soon (lol).

I'd say that's pretty darn good. I'm assuming the fuel tank is between the axles? That should be a good couple hundred pounds of centrally-located mass. Plus the engine up front gives you a lot of leverage against any of that rear overhanging weight.

 

[HazMatt-SKO]

Between the axles, but unless they're paired, that's a big ol' sloshing mass only on one side, likely the shotgun.
If there's room on the driver's side (unlikely, since the start batteries live over there), that would be the place to place a 60 gallon, or whatever the tank's equivalent fluid volume'd be (plus delta density), potable water tank, to counter-balance the load.
However, given the gross mass of the bus, and the low center of gravity for the fuel tank (being at, & below, axle height), I'd bet cashy money that the clever fellers that crunched the numbers factored in that disparity in lading...
Also, the engine is, in a FE dog nose anyway, perched above the front axles, limiting the contravening leverage for excess loading behind the rear axles. The exception being a FF dog house, where the mill is forward of the steers, probably allowing heavier loading behind the drives...

 

[TheHubbardBus]

Between the axles, but unless they're paired, that's a big ol' sloshing mass only on one side, likely the shotgun.

Negative. Two 50-gallon fresh water tanks on either side directly behind the wheel wells (inside), with a larger, longer, and narrower 75-gallon grey water centered between the frame rails (outside). I do not plan on driving any significant distance whatsoever - at least not at speed - with the grey-water tank filled (partial or otherwise).

If there's room on the driver's side (unlikely, since the start batteries live over there), that would be the place to place a 60 gallon, or whatever the tank's equivalent fluid volume'd be (plus delta density), potable water tank, to counter-balance the load.

I have planned to put the propane tank across from the fuel, if at all possible. The fluid weight doesn't completely balance it, but the tank itself weighs more, so it does come close.

The sloshing does concern me. I've considered 2 or 3 smaller tanks to replace each full 50-gallon. I also don't know if baffled tanks are common or easy to find?

I can always travel full or empty... empty if I realize my math sucks. Full if I like paying for diesel. For our purposes, we plan to always have the tanks full - at least while not in use in the boonies - as the bus will serve as another source of H20 to help meet our preparedness goals.

Regardless, Two rows of kids in the back could be the functional equivalent, minus sloshing (guess that depends on the kids), and that's without the additional ballast we'll be adding forward of the front axle (which is also distributed over a much longer axis than the weight in the rear, which hugs the axle).

Not arguing - I posted here because I'm asking. But just visualizing things... it seems to me that so long as I don't exceed the GVWR (and I'm not even close yet from what I can tell), my load is pretty balanced. If my thinking is in error, I appreciate y'all pointing it out!