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paulkeith
04-13-2005, 01:13 AM
http://www.pirate4x4.com/forum/showthread.php?p=3913107#post3913107


like is mentioned over there, its going to eventually be cut off behind the rear braces, and door/side bars will be added from shoulder height to shin height. dash/floor frame is gonna be built out of 2"x2" 3/16", and the seat mounts will be also.

tell me what's good or bad

Paul

ELLLLLIOTTTTT
04-13-2005, 01:29 AM
Trying to figure out that design and how you'd work it into the ZJ's unibody. I'm assuming you've redone the uniframe into some subframe by plating it or whatever but is what the rectangular pieces represent? It just looks like that design is for designing a buggy from scratch. Alls I can really say is don't crimp the DOM at the bends like you did on that ZHEAP! :flipoff2:

paulkeith
04-13-2005, 02:06 PM
i guess its more of a completely new frame. the only zj parts on it are going to the gas pedal, steering column, brake pedal, and maybe grill..haha

i posted here more for the knowledge and people's opinions than so much of a "grand cherokee," but i guess that's where this thing came from


yeah, those bends were nasty. there was so much wrong with it that made it easier and smarter to start over and do it right. the best part is, this time i've got a pro-tools HD bender waiting to get it done. no more "bending" tube in a pipe bender. live and learn, eh?

Kraqa
04-13-2005, 04:10 PM
looks liek what i did kinda. especially from the end.

Cody
04-13-2005, 04:39 PM
Couple thoughts I have


The triangular bars in the 'windshield' frame will drive you nuts as they are now. Most people run a 'v' with the point at the top of the windshield and the spread of the 'v' at the bottom-but use a smaller (like 1" od) tube and only spread the 'v' maybe 4-6". Then your roof spreaders can intersect at the center point of the 'v' and traingulate back towards the 'b' pillars. Does that make any sense? I'll post some pics later if you want.

Once you get the chasis together, you may want to consider putting some kick into the door bars. It just depends on how tight your cabin/cockpit area is, but sometimes straight door bars can get into your way and become obnoxious.

Are you going to put the 305 into the buggy?

Cody

paulkeith
04-13-2005, 11:13 PM
kraqa, i pretty much copied the rear bumper straight from your pics. not copyrighted, is it? :finga:

yeah, i was wondering about those windshield bars getting in the way. i follow what you're saying though. i was also thinking about having the door bars actually function as doors? i think it would be difficult and still retain the actual structural benefit of what they're there to do. any ideas on that? or just not worth it?

yeah, the 305 is goin into this. sm465, np205, 14b, and no front axle yet...but hunting for a 60. i'll hopefully get a little FI action on 305 too.

i've read a little bit on pbb about hrew vs DOM, but what do ya'll think? is DOM the way to go?

consensus on pbb is to ditch the 2x4 3/16 and get round tube. i've already got more than plenty of the 2x4 (100'ish) to get the frame done, and that shite wasn't cheap. i want to use it, and i'm not so concerned with the added weight. with good bracing and triangulation of the frame, i do not think strength will be an issue. what is the right way to go here? why?

Kraqa
04-13-2005, 11:16 PM
i ridden with many peopel with ERW and no problems. i get my 140' tomorrow. 1-3/4 .120

paulkeith
04-13-2005, 11:27 PM
for the places where the frame rails change height,

http://www.prism.gatech.edu/~gtg998h/images/jeepimages/summer05buggy/framewhat.JPG

top or bottom? whichever i do will get plating over the top of the junction, i just can't decide which would be stronger. top has more weldable area, but bottom has smaller moments on the welds.

the more i stare at this, i think that i answered my own question. i think the bottom one with plating over the top of it would be the strongest....opinions?

Swamp boy
04-13-2005, 11:53 PM
Bottom looks better to me.. The top looks like it would be a weak link that would be hard to stengthen..

Kraqa
04-14-2005, 12:09 AM
bottom one. way more strong and you can weld a fish plate onto it.

Cody
04-14-2005, 01:50 AM
Man, round tube would probaby be a lot easier and lighter to use than that square stuff.

HREW/EREW can be used. Seam to the inside. My main cage is DOM but the spreaders and non load bearing stuff is 1.5"EREW. If it's well engineered seamed tube will be OK.

Cody

paulkeith
04-15-2005, 04:37 PM
cody,

do you know off the top of your head, or can you measure for me, the inside-to-inside width of your "b" pillar? a normal zj looks to be around 56"ish, but i was curious what you've got, and if you think it should be wider/narrower etc

edit: and your wheelbase. what is optimal? i am shooting for around 110. do i want longer? shorter?

thanks
Paul

paulkeith
04-19-2005, 09:07 PM
alright fellas, got a new prototype designed, here are the pics:


wheelbase is right around 104"
widest point of the body is 52"

how does that look?

ELLLLLIOTTTTT
04-20-2005, 12:54 AM
i like it. only thing i thought is that you might wanna add more bracing to your corners like at the top of your A pillars where more force would be exerted if you rolled. Also maybe take a couple unneccesary spreaders off at some places.

nathaniel
04-20-2005, 10:10 AM
IMO you should have the front windshield middle bars with bends in them to match the corners. Would make mounting windshields a lot easier and cleaner look. You should probably have one diag. bar between the b's somewhere. maybe get rid of some of the other stuff thats just in the way.

OverkillZJ
04-20-2005, 10:42 AM
Won't those front cross brases get in the way of engine mounting? I like.

paulkeith
04-20-2005, 12:41 PM
yeah, i thought those might get in the way of the bottom of the oilpan, and if they did i was just gonna scrap them.

i'm not really going to put a windshield on this thing, and i figured that they would handle more load straight than with a bend in them.

Cody
04-21-2005, 01:36 AM
Thats good. My only thoughts are similar to what has already been stated.

Some sort of triangulation between the vertical B pillars...

Is all that square tube cross bracing business necessary? Thats going to get heavy quick.

Here is a build thread that a buddy of mine did. He took all his XJ running gear and put it into a buggy--and I think his design is really close to what you are trying to accomplish. Couple things to note---not the '2nd' A pillar in the finished product (check page 3 for a good picture of it), and how the lower 'frame' is designed. I still say you'll be happier if you use tube instead of adding a few hundred pounds of useless weight.

http://www.rockymountainextreme.com/showthread.php?t=11167

you may have to register to see the pics but it's worth looking at.

Cody