As I was removing the luggage racks on my 1987 MCI 96A3 coach a few months ago, I realized that each of the composite brackets going from the ceiling to the wall were actually 45° corner gusset braces. This would make them structural in nature. While removing the seats I realized that these too, were bolted from the floor to the wall thereby creating another brace, of sorts. The metal railing surrounding the driver seat and the knee wall on the passenger side by the stairwell are also bolted on the floor and the wall making them braces as well.
I am not a structural engineer but I worked as a on-site superintendent for a construction company for many years. My concern is that since all of the internal bracing has been removed, wouldn't that allow the walls of the bus to "rack" going around a turn.. Especially a sharp turn? A continuation of this moment could "worry" the remaining structural supports at the ceiling/wall corners and the floor/wall corners until the inevitable happens.
I may be way out left field somewhere, or perhaps just missing something, but is there anyone else on this forum that has had the same concern?
I realize that the installation of the internal walls would provide some structural integrity but that would not be even close to the supports that were removed. ???
I'm sure that I will figure a way to replace some of those braces.
Thanks for your answers. Danny
Even the worst-built bus is much stronger and more crash-survivable than most (but not all) RVs. I wouldn't worry about this! At least our buses won't turn into kindling if they hit something.
John
Not sure... BUT... I know Eagle and Prevost sold shells that never saw luggage racks or seats...
True Iceni. Ive seen a few of those trash trails left by some rvs.
Eagle, I thought of that too. Maybe those are structurally designed a little differently.??
Quote from: IMABUSBOY on September 24, 2015, 12:29:49 PM
True Iceni. Ive seen a few of those trash trails left by some rvs.
Eagle, I thought of that too. Maybe those are structurally designed a little differently.??
of course...they are mo bettah ;D
ps just kiddin ;D ;D ;D ;D ;D
Shell or seated coach structure is identical Prevost. If your talking MCI I built one and ran for years without luggage racks or seats. FWIW Bob My entertainer coach has taller inside height but windows are same as seated coach.
What constitutes "disaster"? I'm trying to just think through the post title. Just my opinion, but driving a bus down a 6% grade in 100 degree temps at 80 mph on a 19 year old under inflated dry rotted tire might constitute "disaster". But converting a coach and removing the seats and luggage racks to build it doesn't constitute "disaster" to me. Thousands and thousands of coaches have been converted and nearly none of them have their original seats, rails, or luggage racks. Some like ours have raised roofs (I was told that was structurally a bad idea) and drive down the road perfect, go around turns just fine, bounce across speed bumps and if you're Craig Holland, you thrash your bus pretty hard in someone's farm field every few weeks or so. What would the "disaster" be? I guess if I blew a steer, and rolled the bus several times, it might flex and tweak.....depending on how severe the rollover was, it might keep its basic structural integrity or it might not. That has a lot to do with how bad the accident was and not whether I left the luggage racks, drivers surround and seat rails intact. An accident severe enough to test the structural integrity differences of a coach with or without said items is an accident that will likely result in much much more injury from A: rolling around in the coach cause your passengers are not buckled.
B: your stuff rolling around because no matter how well you bolt it down, enough of a jolt will send it all scrambling around and I'm pretty sure one wouldn't feel too well after getting clocked with a 300 pound refrigerator.
Also, I would love to actually see data from a bus MFG that indicated the engineers intended the seats, luggage racks and drivers surround to be structurally integral to the coach integrity. I am more apt to think the luggage racks are beefy because they don't want people's heavy luggage crashing down on 50 people's heads when the bus crosses a rough set of train tracks. The seats are beefy because they don't want 50 people tossed about in the bus when he brakes hard and it breaks loose from its mount. Sometimes I think we overthink stuff on this forum just a little and need to step back and realize that certain aspects of coach safety are extremely important, but some discussion here is more banter than serious safety issue. I place this in the latter category.
My life is full of risks. They are calculated, but they are there. Driving a converted bus with a roof raise and no luggage racks, seat rails, or drivers surround isn't one of them. All that being said, if it's gonna keep you awake at night, I think you could creatively keep the luggage racks and incorporate them into your interior design. They are strong and could hold a ridiculous amount of weight.. You'd have to come up with doors for them...but I think it could be made to look really nice. The drivers surround could stay and wouldn't cause issues with your conversion, but your seats? Not sure how you'd work that out. You could keep the seat rails for added stiffness, they are under a bit of load. Trust me. When we removed
ours every weld we cut, made the whole rail pop. When we raised our roof, we welded in 1/8" thick square steel tube as cross braces between the window openings we weren't using. That's twice the thickness of the mild steel ribbing that comes stock with a 9. Reskinned with 1/8" aluminum sheet, also nearly twice as thick as the stock skin. That's about all we did to strengthen it.
Sent from my iPhone using Tapatalk
The stuff you mentioned are most definitely structural, but you must consider how different uses place different loads on the structure.
The 'live loading' of passengers & their loose luggage is very different than the stuff we put in. When you remove the load of all the passengers, you don't need the structure to 'secure' them.
40 people & their stuff at ~250# each = 10,000# .
My better half & I with all of our loose stuff is well under that !
Structurally wise, all the seats and racks that are attached to the walls and ceiling provide some support. My transit did not have any overhead cargo. Just seats. I don't think much is added on the seats to the structure. When I finished my bus with my wife and I in it and all our junk in with tanks full I weighed the bus and was 5,000lbs below the maximum gvw rating. Not many motorhomes made with that kind of surplus.
On my truck, I built it with 1.5" square tubing with 1/8" walls welded on 16" centers. I visited the shop that built my box (professionally built box, otherwise the insurance company would not insure it. They didn't care about the interior) when the walls were completed, but the roof wasn't in yet. I could rock the truck with the walls without any visible flexing. So add to that the roof, then the outside .060" skin glued to the tubing, then also the 3/4" horizontal Apitong (type of mahogany) slats screwed to the interior of the tubing, then the 1/4" interior plywood, and you then have a very strong wall. Buses are built very strong, with schoolies and transits being the strongest because of their service. Good Luck, TomC
One thing most of us converting do is add at least 1 or 2 partition walls which I would think produce far more support than the overhead racks or seats. Any thing is able to be destroyed you just have to decide what will fit your tolerances. Sometimes I think I can destroy a anvil with a rubber hammer! If you feel uncomfortable run away fast.!!! Bob
I would think that the bracing for the seats and luggage rack had more to do with them being capable of doing their design task than structurally re-enforcing the shell. Anyway, since there are lots of converted coaches on the road, there is ample performance history to tell us whether they are not capable of holding up to our use. I see no reason to worry about a scenario, even if I can imagine it, that seems unsupported by millions of miles of real world experience.
Oh, I think I rubbed some people the wrong way. Didn't mean to! I'm not worried that my coach will collapse. I realize that the weight of the luggage of 50 people riding overhead, would create much more lateral stress on a turn than a coach with all the weight at the floor level and below. I'm not even concerned about the scenario I described coming true, but it crossed my mind at the time. Given by background, I guess I always think in that direction. Old habits are hard to break. My wife and I love our coach and enjoy it every chance we get! We love bus people and the bus culture! We have a class A,(different people), but there's no comparison to 'The Sparrow'!
We are the talk of just about every RV park or campground we visit. It seems that people just have to stop and say hi. We logged 3,088 miles this month on a 9 day trip to Louisiana, Texas and back home through Texarkana Little Rock Ark and Nashville.
We're planning a 5-6 day trip to Niagara Falls in a few weeks.. mid Oct. That will be our last trip at least the rest of this year. We need to build up more vaca time and $$$. :( We want to do all we can before winter sets in. ;D I cant wait till she retires! As stated here, I am much more concerned about a tire than a roof collapse!
Thanks to all of you for your wisdom! What do I know.. after all, I'm just a bus boy. haha Danny
I don't think that anyone was offended, and the question was worth asking.
Quote from: Lin on September 25, 2015, 06:55:03 PM
I don't think that anyone was offended, and the question was worth asking.
agree ;D
Quote from: kyle4501 on September 25, 2015, 05:59:48 AM... 40 people & their stuff at ~250# each = 10,000# .
Interesting ... I'm in the middle of a repower. The new engine and transmission (according to published specs) are almost 1500 pounds lighter than the ones taken out. Yesterday, we dropped the rear axle -- I've not had a chance to weigh it and there are no published numbers, but to take it out, we dropped it onto a pair of 800 pound-rated transmission jacks, one under each brake drum, and one of them bent!!! (It's a big, heavy low-floor axle with differential on one side, and a pair of big planetary gears one on each side with a low slung housing between them. It's a monster.) I'm conservatively guessing that the Meritor axle and suspension (air instead of leaf springs) that's going in it's place is 700 pounds lighther. My total savings in powertrain will be over a ton!
The empty weight of my bus before I began stripping seats, etc. out was 19,000 pounds, but it was designed to carry a total of 98 passengers plus driver. I'm assuming that the design criteria was more like about 165 pounds per person (average men, women, children etc.) but that still gives a Gross Weight of 36,000 pounds. If I consider the weight of seats etc. removed and a savings of approx. 2000 pounds in powertrain, I'm thinking my new "empty weight equivalent" is down to something like 16,500 pounds. Can I really have a margin of 20,000 pounds before I get up to design Gross Weight? (Unfortunately, since the bus was made before modern GVWR's, I can't find a published GVWR,
It will be interesting to weigh my bus after full conversion and see how the numbers come out. I don't think that I've taken out any components that added to structural strength of the shell.
It shouldn't be a problem after all MCI sent bare shells to Marathon,Custom Coach and others without the luggage racks and seats to be converted back in the 80's,they didn't even have the seat rail in the floor
If this were a problem, I believe we'd have seen evidence of it long before now.
Duty cycle matters.
Occasional use is very different 500 to 1000 miles per day.
Sooooo, if it doesn't bend in half when you make the first hard turn out of your driveway, that is a good sign that it will probably last longer than you will use it. ;D
I will say this Danny, these coaches flex more than I ever imagined they would and that surprised me. I changed my front passenger steer tire yesterday and had to jack up the coach a little on that side. With it on a bottle jack, I can't get the front door deadbolt to lock and my bathroom door (half way down the coach) rubs when I close it. So there's definitely flex there that may not be as pronounced with the luggage racks and seats in place, but I don't worry about it much. As soon as I drop it off the jack, all returns to normal. The metal must have memory haha
Sent from my iPhone using Tapatalk
I have to disagree with the generalization above about flexing. I have had three Prevost coaches. I could support the chassis at the four chassis support points. Then I could jack any one point and the support point on the opposite side of the coach would come up at the same time with no apparent twisting of the chassis. On all three coaches I could jack up either front support point and it had no impact on how the door opened, closed or latched.
We have the fun of doing our own Bus Conversions. How long the government will allow the average converter to continue doing this is not clear. Lots of endeavors we have enjoyed as younger people are now no longer doable or in some instances even legal.
Enjoy it will we can? I believe so. Over time our own leaders will see that we are given less and less freedom to do something meaningful in our own way and fashion. Automotive smog laws come to mind. Some state vehicle inspections also apply.
We are responsible for what we do. This also includes Bus Conversions. Every time we mess with OEM stuff things may slightly change. Sometimes we are not even aware of this. I know I spent lots of time pondering low probability repercussions of my actions.
Good ole EPA not long ago they were checking trucks here for the DEF seems like some truckers are just running R/O water in the system,lol truckers you would think one would be smart enough to pee in the water
Urea or diesel fluid?
Didn't know that was even possible. Our local bus dealer recently had a new bus being brought in. The steering wheel holder filled the DEF tank with water by accident. It coded and derated. Had to be hauled in on flatbed.
DEF is 70% water some a little less
Quote from: Jon on September 27, 2015, 04:29:50 AM
I have to disagree with the generalization above about flexing. I have had three Prevost coaches. I could support the chassis at the four chassis support points. Then I could jack any one point and the support point on the opposite side of the coach would come up at the same time with no apparent twisting of the chassis. On all three coaches I could jack up either front support point and it had no impact on how the door opened, closed or latched.
Jon your prevosts sound like they don't flex much. But both MCI's I currently own flex enough when you jack them kittywampous that the door can be hard to lock or rubs different when you close it. Can't speak for prevosts but both my MCI's exhibit this.
Sent from my iPhone using Tapatalk
I have a MCI that twists when it airs down in my driveway,cant open wheelchair door and entry door is hard to bolt if not aired up or blocked before air drops.
Chuck
I don't know about Jon Prevosts but my 1997 Prevost with 4 the point HWH hydraulic levelers would twist and flex till the door would not open or close it was one of the few that had the HWH.
Last I heard they won't install the HWH hydraulic levelers on a Prevost now if one has slides
I was warned by Prevost to be careful and make sure all 4 were down before leveling.
I think they all flex I have seen a lot broken granite stair ways on the H-45 Prevost caused from flexing
Clifford, the fact you mention HWH suggests a conversion that may not have had levelers located at chassis support points. I haven't seen any flex on my three coaches, including the current one with Prevost slides.
That is supported by this report http://altoonabustest.psu.edu/buses/reports/429.pdf?1376405644 (http://altoonabustest.psu.edu/buses/reports/429.pdf?1376405644) which does not show any flexing that impacts the operation of any windows and doors.
But a bigger question is why use HWH levelers when the Prevost chassis has the level low system on motor home shells?
I didn't the like airs bags when parked in high winds.I know Dick has a 2002 XLL with a slide the 1st from Prevost his bus will flex enough the slide will give him problems some times
My HWH levelers when installed had a Prevost rep there for 3 days if they were wrong he told the people in Iowa wrong but it would flex
;D I have read that test before the thing that impresses me the most was the fuel mileage on the D-13 engine @ 435 hp it's hard to believe a 2012 engine overall average was 3.77mpg ? you know of any test on the other models beside the X3 I don't seem to be able to find one
No, I cannot find tests on the H3, XL or XLII. I wish I could.
I am not impressed with the knowledge of Prevost reps. Too often if you ask a question they make up the answer or tell you what they think you want to hear. My guess is they have never spun a wrench.
Jon,
I read the data sheet link you posted and noted that they specifically were looking for "permanent" deformation during jacking. Nothing was mentioned about temporary deformation. My coach always bounces back to normal once on all fours....er all eights. Are you using air leveling or actual hydraulic jacks?
Sent from my iPhone using Tapatalk
I just noticed that test was done on the X3-45 commuter coach made in America in New York I saw a couple of demo units in Phoenix last year.
It's hard to believe Prevost would build a bus with a life span of 12 years or 500,000 miles for the transit authorities surely they will last longer than that.
That is why the test was done I understand it now different ball game ;D it only needs to last 12 years and our tax dollars buy new ones this throw away society we live in just amazes me
Twelve years or 500,000 miles is the FTA standard for useful life on heavy duty transit buses. It's been this way for a long, long, time. That doesn't mean that the agency will not run them more than that. My transit bus (the one I converted) had 674,753 miles on it when I bought it.
At our property, we routinely run them for quite a bit longer than useful life. To some degree it depends on the bus too. As they age, maintenance costs go up. Sometimes there are other issues like structural problems to consider. We keep our MCI's well past their FTA useful life, but can't wait to get rid of 12 Novas as soon as possible. They were early CNG units and have been mucho headaches. How long buses are kept varies from property to property. For new purchases, the FTA will pay 80% of the capital cost for heavy duty buses. The system must fund the other 20% from local or state money and pay all the operating cost.
The ole girl doesn't look too bad for 700K does she?
(https://lh3.googleusercontent.com/-TBVwZFA0Cqs/VT2XhKO7xrI/AAAAAAAABQk/TxUCQR_ViPo/s800-Ic42/P1000832.JPG)
(https://lh3.googleusercontent.com/-HlQGIxe7UuM/VT2XBsVLn1I/AAAAAAAABOM/IZCU_LUdd5c/s800-Ic42/P1000811.JPG)
That's my point Prevost never built a bus to those standards before a tour bus operator would flip out with the 3.77 average mpg,I don't understand Prevost building that bus in the USA maybe for sales to cities that have a charter prohibiting buying non USA who knows
With all the cites in the Phoenix area having 1 transit authority seems like they get new buses every week on top of the billions they spend on the light rail system going nowhere In Vegas and Phoenix you can't buy a transit bus now they are scraped out but you can buy the wheels
Yeah, I think you're right. 3.77 mpg is average mileage for a transit bus in transit service. A tour operator is not going to be happy with those metrics. I wonder what kind of service they tested it in to get those numbers. If it was transit service, I can believe them.