Fame dimensions, please.
 

Fame dimensions, please.

Started by someguy, August 09, 2020, 03:38:20 PM

Previous topic - Next topic

someguy

I'd like to do some stress analysis on the J4500 frames.

Could anyone supply me with measurements of the various members ?  Lengths, size, thickness.

I'm starting with a 2D analysis of the stress in the side truss.  I want to investigate what happens when a slideout is added.

Thanks.

ktmossman

IIRC, much of that info is in the parts books.  They break it down to every nut and bolt.
Kevin Mossman
2006 MCI J4500
Dallas, TX

someguy

Quote from: ktmossman on August 09, 2020, 03:50:40 PM
IIRC, much of that info is in the parts books.  They break it down to every nut and bolt.

I haven't seen the dimensions of any of the structural elements.  If you have, I'd love to know what section they are in.

buswarrior

That sort of stuff is likely going to take a call to MCI.

There's no reason for the common bus fleet to need that information to maintain the coach?

Happy coaching!
Buswarrior
Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

someguy

I'm hoping that somone has the walls torn apart on their conversion and can take some measurements.

luvrbus

J uses the bridge truss design the framing for the slides just transfers the stress on good slides,the framing on the Happy Jacks used in 5 th wheels and entry level motor homes don't have much stress they are nothing but a hole in wall,you need to buy a bus all this analyzing is going to make you a basket case in a year jump in and go for it like the rest of us the factories engineers have done the work for you   
Life is short drink the good wine first

Dave5Cs

Someone had to say it, LOL Yea Clifford  ;)
"Perfect Frequency"1979 MCI MC5Cs 6V-71,644MT Allison.
2001 Jeep Cherokee Sport 60th Anniversary edition.
1998 Jeep TJ ,(Gone)
Somewhere in the USA fulltiming.

someguy

Quote from: luvrbus on August 09, 2020, 08:19:48 PM
J uses the bridge truss design the framing for the slides just transfers the stress on good slides,

Absolutely not !

The top image is my unscaled drawing of the side of a J.   You remove all the strength of the truss when you remove part of it to install a slide.   I am not aware of any slide out system wherein the slide itself makes up for the removed section. 

In all applications that I am aware of an external truss must be built up to replace the section of truss that has been removed.  This is the case with the factory Prevost slides wherein the strength removed from the sidewall is replaced with strength in the baggage compartment.

Quotethe framing on the Happy Jacks used in 5 th wheels and entry level motor homes don't have much stress they are nothing but a hole in wall,
I have a 5th wheel with 3 slides in it.  5th wheels and entry level motor homes have a stand alone truck like C channel frame that does not get cut or weakened by the slideout.  That is definitely not the case with the bus "frame".   

Quoteyou need to buy a bus all this analyzing is going to make you a basket case in a year jump in and go for it like the rest of us the factories engineers have done the work for you   

The factory engineers have not "done the work for" anyone putting a slide in an MCI.

I'm in no rush to do anything until I figure out what I want to do. Proper preparation prevents piss poor performance.   With dimensions, I can do a rough analysis on a frame in a couple hours.  It is time well spent.

buswarrior

When you discover that the J defies the engineering tests, and by calculation, shouldn't be capable of holding its own self up off the road, never mind a slide...

Then what?

Fill in the appropriate baggage bay door areas with structure and get building?

The mileage typically put on a bus conversion, it will matter little whether you are too heavy, too light, whether it will pass an Altoona test... the big engine down the back will push it along.

If these calculations are part of the hobby, you will get far more accurate measurements if you go find a coach to measure in person. Big coach body shop, coach wrecking yard, refurbishment shop, someone will have a J model eventually, with its pants down.

Happy coaching!
Buswarrior


Frozen North, Greater Toronto Area
new project: 1995 MCI 102D3, Cat 3176b, Eaton Autoshift

ktmossman

I know I've seen it in the MCI docs before but I can't find it now.  I have most of that structure exposed (from the inside) right now on mine, but it will be Saturday before I have a chance to get back out there.  Let me know exactly what dimensions you are looking for and I can get them.

Kevin Mossman
2006 MCI J4500
Dallas, TX

luvrbus

The same outfit in Canada installed slides in the Prevost and MCI till Prevost acquired the company ,all they added was a beam above the baggage compartments and not much of a beam either.Flat floor factory sides were never a option in the Prevost till 2016 and only 1 was available installed in the salon area,Slides in the Prevost factory installed slides are rated for 1500 lbs same,MCI and Prevost both have the same designed frame now that Eagle used since 1957 .I have seen to many slides installed at Newell, Country Coach, Marathon,ForeTravel and HWW so someone did the engineering.I don't how it is now but for years you could only buy the MCI or Prevost with 1 factory installed slide the converter would add 3 HWH slides.I too own a 40 ft 3 axle 5th wheel those slides are not much I wouldn't have another electric slide with a outside flange around the slides   
Life is short drink the good wine first

Jim Blackwood

I went with the larger bus specifically to avoid slides. No way a slide equipped bus can have the structural integrity of one without them.

Jim
I saw it on the Internet. It MUST be true...

sledhead

I installed a kitchen,living room slide in my old MCI 102c3 and never had a problem in the 10 years we ran it down the road

it can be done and it was not that hard

dave
dave , karen
1990 mci 102c  6v92 ta ht740  kit,living room slide .... sold
2000 featherlite vogue vantare 550 hp 3406e  cat
1875 lbs torque  home base huntsville ontario canada

someguy

How wide is a window in a E/J ?

someguy

Quote from: sledhead on August 10, 2020, 08:39:30 AM
I installed a kitchen,living room slide in my old MCI 102c3 and never had a problem in the 10 years we ran it down the road

it can be done and it was not that hard

Pictures ?  How did you reinforce the frame ?