Just wondering.
Thanks
Matt
There is no frame on a 4106, at least not in the traditional sense. Same for nearly all GM intercity coaches. They are true monocoque construction with the bulkheads, lower bay floor, and shell making a structural unibody construction similar to an airplane's fuselage. There are some steel panels involved, like around some of the windows, the front and rear caps, and a few other places. The remainder of the construction is aluminum but for some structural steel in the engine cradles and a few other supporting sub-structures.
Truly an engineering marvel that our GM buses roll down the road with no frame rails.
Here is a photo of the underside of a 4106 we just purchased
MCI's and Prevost have no frame either , GM has steel roof bows for roll over protection and engine mounts from the roof,GM's have enough steel to rust too
Can some one tell me if a mci dl3 has frame rails
Quote from: 6805eagleguy on June 07, 2021, 04:58:57 PM
Can some one tell me if a mci dl3 has frame rails
No frame on the MCi DL3
Don't MCI and Prevost buses have more of an exoskeleton than a GM bus though? If you pulled off the skins on one of those you would still have the outline of a bus made by the exoskeleton. On a GM, pull off the skins and not much is left.
What else does it really need.?? >>>Dan
Quote from: richard5933 on June 07, 2021, 05:34:43 PM
Don't MCI and Prevost buses have more of an exoskeleton than a GM bus though? If you pulled off the skins on one of those you would still have the outline of a bus made by the exoskeleton. On a GM, pull off the skins and not much is left.
Yes Prevost's do have an exoskeleton. I found this diagram in the parts manual.
(https://www.crystalpoint.com/cpdownloads/public/outgoing/Freds/Framework.jpg)
Plus when I was installing my solar panels, I first drilled through aluminum and then steel...
"On a GM, pull off the skins and not much is left."
And you think that is a good thing? :)
Quote from: Dave5Cs on June 08, 2021, 12:41:18 PM
"On a GM, pull off the skins and not much is left."
And you think that is a good thing? :)
Yes, it's monocoupe and needs no exoskeleton, neither does our Grand Cherokee toad...
LOL GM sure have a ton of rivets holding the skins on to metal for a true monoscope
Well back in the day they couldn't use computer models to determine exactly how many rivets a bus would need holding it together to last the designed service interval, so they just put an absolute crapload of them on. 60+ years later, here we are enjoying them still.
Lol ....Exoskeleton = frame... aka birdcage Maserati...
MCI are similar and if you pull off the inside wall panels and the outside skin without supporting the rest it would collapse. The baggage bays are supported by the above Monocque Frame above but only as the panels support it. The front and the rear are supported with the Bulkhead front and rear and the engine is supported by a truss on either side of it that it sits on.
Found this on an engineering site;
Monocoque means "one shell" or "single skin". Almost nothing is a true monocoque -there's always some load condition that can't be sustained by a single shell. It's become a marketing term.
Wonder if some aircraft are considered monocoupe? And I'm not even thinking wing here just fuselage.
Quote from: dtcerrato on June 09, 2021, 06:38:01 AM
Wonder if some aircraft are considered monocoupe? And I'm not even thinking wing here just fuselage.
Most are I believe - it's a design far more common in the skies than on the roads.
My guess is that many of the engineers working on our earlier buses were former military men & women that were involved in the creation of the fleets of planes used during WWII. That experience translated directly to the construction used on our buses. Most planes during that era were monocoque, which apparently translates literally as 'single shell'.
Here's a breakdown of the terms used to describe the various types of vehicle construction: https://www.motortrend.com/news/body-on-frame-vs-unibody-vs-monocoque-what-is-the-difference/
Reviewing the link Richard posted, earlier mention of our Jeep Cherokee toad being Monocoupe is incorrect as it is more accurately unibody. FWIW
As far as the relation between military (WW2) machines & our vintage aluminum buses - TOO COOL... :^ - on not just the bodies but also the power plants...
One of the first monocoque aircraft was the Aircoupe which was an early metal skinned low wing 2 seater but even with those you have metal ribs inside.
Exoskeleton means literally the skeleton is on the outside. Not really the right word for a perimeter skeleton that is on the inside.
Jim