Various types of chassis sections used in Ladder frame construction

offroad_maniac · 24th February 2010, 20:32

Here is one pic showing Scorpio chassis (Source:mahindraengineering.com)

The details given as below:

Ladder frame

Tubular & formed x-member

Fully welded components

Side members as C IN C box section, stitch welded, 3 piece variable section & multi-plane bending

Whats is stich welding. is it a type of welding done keeping a small gap at frequent intervals so as to act as stress busters?
AHAIK, Scorpio chassis do not have big holes or any holes in the side rails.

Whats is the meaning of 3 piece?
What signifies the Red,Blue & Orange colors? Are they of different thickness for weight reduction/ strength?

Last black chassis is of Jeep CJ7- again C in C ?

SPIKE ARRESTOR · 24th February 2010, 22:25

@offroad maniac stitch welding is a term used for co-relating a weld joint to that of stitching a cloth, during welding gaps are not provided for stress relieval, the holes are punched in the blank itself before the bending/forming process,red,blue,green are used for representing various sections in a CAD layout, the thickness may or may not be similar,the last pic has a C in C construction

Spike

offroad_maniac · 25th February 2010, 05:34

Quote:

Originally Posted by SPIKE ARRESTOR

@offroad maniac stitch welding is a term used for co-relating a weld joint to that of stitching a cloth, during welding gaps are not provided for stress relieval, the holes are punched in the blank itself before the bending/forming process,red,blue,green are used for representing various sections in a CAD layout, the thickness may or may not be similar,the last pic has a C in C construction

Spike

Thanks Spike for answering my queries. you know I am so much interested in chassis etc as it is a base for any vehicle, & its design & strength is very important for an offroader.

Whats your fav. type? (If I may ask)

Sutripta · 25th February 2010, 21:57

Quote:

Originally Posted by offroad_maniac

AHAIK, Scorpio chassis do not have big holes or any holes in the side rails.

Re: the big holes seen in the riveted chassis shown in post # 25, check out the spatial relationship between the holes and the rivets.

Regards
Sutripta

offroad_maniac · 25th February 2010, 22:28

Quote:

Originally Posted by Sutripta

Re: the big holes seen in the riveted chassis shown in post # 25, check out the spatial relationship between the holes and the rivets.
Regards
Sutripta

Yes, but that chassis is of Ford. I am talking about Mahindra Scorpio Chassis. It has got very small holes that too in lesser numbers.

Sutripta · 25th February 2010, 23:05

Quote:

Originally Posted by offroad_maniac

Yes, but that chassis is of Ford. I am talking about Mahindra Scorpio Chassis. It has got very small holes that too in lesser numbers.

Was saying why the Scorpio chassis does not have/ need big holes. IMHO, the big holes in the Ford chassis are for access to the underside of the rivets. The Scorpio chassis is welded. If the primary purpose of the big holes in the Ford chassis had been anything else, the outer C section would also have holes punched in them!

See also post # 30. Also I would think that there should be some means of air circulation, else there will be condensation/ rusting problems.

Regards
Sutripta

SPIKE ARRESTOR · 26th February 2010, 14:48

Quote:

Originally Posted by offroad_maniac

Thanks Spike for answering my queries. you know I am so much interested in chassis etc as it is a base for any vehicle, & its design & strength is very important for an offroader.

Whats your fav. type? (If I may ask)

@offroad_maniac yes you may, it is my pleasure, i love the chassis sections of old CJ3Bs (KISS-Keep it simple and stupid), only thing is they are susceptible to overloads as prevalent in indian conditions (overload e.g. commander 650)

Spike

vinod_nookala · 26th February 2010, 14:53

Quote:

Originally Posted by SPIKE ARRESTOR

i love the chassis sections of old CJ3Bs (KISS-Keep it simple and stupid),

Spike

Strange you don't like the improved Mahindra's NGCS chassis?

If so why? How is old 3B chassis better than NGCS in pure off roading point of view? (no over loading, handling, cmvr etc.. etc)

SPIKE ARRESTOR · 26th February 2010, 15:11

Quote:

Originally Posted by vinod_nookala

Strange you don't like the improved Mahindra's NGCS chassis?

If so why? How is old 3B chassis better than NGCS in pure off roading point of view? (no over loading, handling, cmvr etc.. etc)

@Vinod i didn't say that, i like CJ3B as it is simple, the best thing about it is despite being so simple it can handle a good amount of abuse, one of the best thoughts on it is the K member, any idea if any CJ3s came with cross braces or not?

Spike

vinod_nookala · 26th February 2010, 15:23

Quote:

Originally Posted by SPIKE ARRESTOR

despite being so simple it can handle a good amount of abuse, one of the best thoughts on it is the K member, any idea if any CJ3s came with cross braces or not?

Spike

Yes K member is damn tough and best for towing! Why was it discontinued? My MM540 has it. But later models got rid of it. Why?

No idea about cross braces...what are they?

SPIKE ARRESTOR · 26th February 2010, 15:56

@Vinod the reason for discontinuing I guess is the packaging of fuel tank assembly at the rear overhang, cross bracing is done to improve the torsional rigidity of the chassis i am attaching a pic for this.

Spike

vinod_nookala · 26th February 2010, 17:14

Quote:

Originally Posted by SPIKE ARRESTOR

@Vinod the reason for discontinuing I guess is the packaging of fuel tank assembly at the rear overhang, cross bracing is done to improve the torsional rigidity of the chassis i am attaching a pic for this.

Spike

Spike my 540 has a K member and its fuel tank is located behind. how?

SPIKE ARRESTOR · 26th February 2010, 17:23

@Vinod good information, can you post the pics of your rear overhang area

Spike

headers · 26th February 2010, 17:23

Quote:

Originally Posted by SPIKE ARRESTOR

@Vinod the reason for discontinuing I guess is the packaging of fuel tank assembly at the rear overhang, cross bracing is done to improve the torsional rigidity of the chassis i am attaching a pic for this.

Spike

Quote:

Originally Posted by vinod_nookala

Spike my 540 has a K member and its fuel tank is located behind. how?

Yours must be an old model to feature the K member. Newer vehicles do not have it.

There will be an entire design team that decide on what to remove and what NOT to remove on new vehicles.

Modern software even allow the design dynamics to be tested virtually before finalising the BOM.

And I guess the different coloring of the chassis is done by the CAD CAM packages to distinguish between various pieces of the BOM.

Interesting thread

vinod_nookala · 26th February 2010, 17:40

Quote:

Originally Posted by SPIKE ARRESTOR

@Vinod good information, can you post the pics of your rear overhang area

Spike

Will upload it tom

24th February 2010, 20:32	#31
offroad_maniac BHPian Join Date: Aug 2008 Location: Thane-Mumbai Posts: 492 Thanked: 154 Times	Here is one pic showing Scorpio chassis (Source:mahindraengineering.com) The details given as below: Ladder frame Tubular & formed x-member Fully welded components Side members as C IN C box section, stitch welded, 3 piece variable section & multi-plane bending Whats is stich welding. is it a type of welding done keeping a small gap at frequent intervals so as to act as stress busters? AHAIK, Scorpio chassis do not have big holes or any holes in the side rails. Whats is the meaning of 3 piece? What signifies the Red,Blue & Orange colors? Are they of different thickness for weight reduction/ strength? Last black chassis is of Jeep CJ7- again C in C ? Attached Thumbnails
	() Thanks

24th February 2010, 22:25	#32
SPIKE ARRESTOR Senior - BHPian Join Date: Nov 2009 Location: Germany Posts: 2,854 Thanked: 1,532 Times	@offroad maniac stitch welding is a term used for co-relating a weld joint to that of stitching a cloth, during welding gaps are not provided for stress relieval, the holes are punched in the blank itself before the bending/forming process,red,blue,green are used for representing various sections in a CAD layout, the thickness may or may not be similar,the last pic has a C in C construction Spike Last edited by SPIKE ARRESTOR : 24th February 2010 at 22:27.
	() Thanks

26th February 2010, 15:56	#41
SPIKE ARRESTOR Senior - BHPian Join Date: Nov 2009 Location: Germany Posts: 2,854 Thanked: 1,532 Times	@Vinod the reason for discontinuing I guess is the packaging of fuel tank assembly at the rear overhang, cross bracing is done to improve the torsional rigidity of the chassis i am attaching a pic for this. Spike Attached Images Last edited by SPIKE ARRESTOR : 26th February 2010 at 15:58.
	() Thanks

26th February 2010, 17:23	#43
SPIKE ARRESTOR Senior - BHPian Join Date: Nov 2009 Location: Germany Posts: 2,854 Thanked: 1,532 Times	@Vinod good information, can you post the pics of your rear overhang area Spike
	() Thanks