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View Full Version : Upper Tri-link Design. . .critique



gearhead313
01-23-2005, 01:08 PM
http://img.photobucket.com/albums/v123/gearhead313/upperdesign1.jpg


nothing new and inovative what-so-ever. I want to use all straight tube, not sure what size or anything yet, belly side jonny joints, etc.

all my cad is on my laptop which is broke, so i had to use a ghetto program on my house computer, so i know the drawling is eh. I figured I'd start with this and get creative from there if necessary.

Give me all your critiques and ideas to help me out like what size/type of tubing would be ideal, etc. I at least want to get the idea down, then apply it to my zj's geometry when I'm ready.


also, my 14b is already really nicely setup with a verticle mount design which im not going to change, so im working off that.

Nordic1
01-23-2005, 01:34 PM
Strickly IMO... Go with 4 link... With three link you won't be able to center the axle once everything is welded in plus there is quite a bit of body rolll.

robselina
01-23-2005, 02:02 PM
Use a 3/4" Heim at a minimum. I'd just use 1" SCH80 pipe with weld in tube insert for the heim. That's plenty beef considering this thing will never meet a rock.....

OverkillZJ
01-23-2005, 02:03 PM
Strickly IMO... Go with 4 link... With three link you won't be able to center the axle once everything is welded in plus there is quite a bit of body rolll.

Funny. Especially considering stock WJ's use a 3 link.

gearhead313
01-23-2005, 02:55 PM
trust me, i'd like to go 4 link, but the axle is already setup to run a 3 link, and im not going to change it. I understand its driving charactoristics, but im fine with that.


Think the sch80 pipe will really be enough? I believe it was setup before with a 1" heim, but im not sure. I'll go measure later.

robselina
01-23-2005, 04:40 PM
Think the sch80 pipe will really be enough? I believe it was setup before with a 1" heim, but im not sure. I'll go measure later.

Measure the hole and use a heim that your brackets were made for. As for the 1" sch 80 pipe, it's like 1/4" thick, I've used it on my steering on the waggy and it's stout stuff. I also used it on my rock sliders on the ZJ. If it were lower links, I'd say no, not enough, but for the uppers, definitely. BTW, if it's a 1" heim you'll need a bigger tube insert which means bigger pipe or tube...check this place out for the hems and adapters, it's where I got mine:

http://www.polyperformance.com/shop/home.php?cat=25

http://www.polyperformance.com/shop/home.php?cat=98

gearhead313
01-23-2005, 05:52 PM
awesome....thats what i was looking for.


any need to change the design at all?

Nordic1
01-23-2005, 09:16 PM
Strickly IMO... Go with 4 link... With three link you won't be able to center the axle once everything is welded in plus there is quite a bit of body rolll.

Funny. Especially considering stock WJ's use a 3 link.


I thought they were 5 link? 2LCAs, 2UCAs and a trilink....

chadjans
01-23-2005, 11:11 PM
turn your joint 90*

ELLLLLIOTTTTT
01-23-2005, 11:39 PM
Strickly IMO... Go with 4 link... With three link you won't be able to center the axle once everything is welded in plus there is quite a bit of body rolll.

Funny. Especially considering stock WJ's use a 3 link.


I thought they were 5 link? 2LCAs, 2UCAs and a trilink....

:wrong: a-arms are a beeyotch.

Jim311
01-24-2005, 12:32 AM
It'd be nice if you could somehow make the threads adjustable without having to remove the entire arm to adjust it. Use a couple of jamb nuts and whatnot to achieve that. I'm big on ease of adjustability!

Nordic1
01-24-2005, 02:28 AM
It'd be nice if you could somehow make the threads adjustable without having to remove the entire arm to adjust it. Use a couple of jamb nuts and whatnot to achieve that. I'm big on ease of adjustability!

yea but how many times do you have to adjust it?

ELLLLLIOTTTTT
01-24-2005, 02:43 AM
It'd be nice if you could somehow make the threads adjustable without having to remove the entire arm to adjust it. Use a couple of jamb nuts and whatnot to achieve that. I'm big on ease of adjustability!

yea but how many times do you have to adjust it?

if its like anything else on a jeep then you'll put it on, then adjust, then adjust it back just a little bit. Then maybe add some more lift then need to adjust it again, etc, etc. I'll agree, ease of adjustability is nice.

gearhead313
01-24-2005, 11:11 AM
I'd like to turn it 90*, but i can't. thats what im stuck with, so thats what i have to make "work".



I like the idea of having it more readily adjustable. I'll think about that and see what i could come up with.

JeepinHank
01-24-2005, 12:06 PM
I think it would be possible to make the tri-link adjustable. At least a little bit. If your heep is anything like mine, nothing on it is perfectly square, so you'll need to be able to tweek it a little anyway.

Just make each arm's length adjustable. (on the frame side.)

If you make the heim adjustable as well, you could adjust alignment / lateral position and pinion angle independently, right? Or am I not thinking about it straight?

Timzjatl
01-24-2005, 01:40 PM
If you don't turn the heim, you will rip them up in very short order (a matter of weeks)... The side loading on that design is tremendous. Trust me, I ran what you are showing above, and killed 2 heims in a month (chromo, expensive ones) so I flipped the heim and had no more problems for the life of the system.

gearhead313
01-24-2005, 03:13 PM
Just make each arm's length adjustable. (on the frame side.)

If you make the heim adjustable as well, you could adjust alignment / lateral position and pinion angle independently, right? Or am I not thinking about it straight?

I think that's possible, but not something I was going to do. I'm hoping i'll get everything square enough not to need to do that.

Most likely i'm just going to cut apart my upper RE arms and use the frame side as they are, no adjustments. I think you have an idea, but im not sure how it would work with triangulated lowers. That might be TOO much adjustment for me!





If you don't turn the heim, you will rip them up in very short order (a matter of weeks)... The side loading on that design is tremendous. Trust me, I ran what you are showing above, and killed 2 heims in a month (chromo, expensive ones) so I flipped the heim and had no more problems for the life of the system.

I dont understand how that positioning of the heim will so affect its life span. There shouldn't be any difference in side loading between the two. Both ways, with a lateral load on the axle will be on the bolt the same.....pulling it in either direction. I also think the force on it (other than longitudinal axle wrapping cycles) will be lessend with properly placed lower control arms. Please let me know what I probably have wrong in my thinking. Again, the axle is so nicely setup this way, I really hate to change it.

gearhead313
01-24-2005, 03:14 PM
this is the only way i could think to make the upper adjustable, but it doesn't seem like it will be nearly strong enough to hold up:

http://img.photobucket.com/albums/v123/gearhead313/upperdesign2.jpg

JpRngr
01-24-2005, 04:16 PM
You need to lay the heim flat so the bolt faces up and down. With it how you show in your drawing, there is nothing to control side to side movements. There is only a little collar holding the ball of the heim in from the side. With it laying flat, the side load will be against the casing of the joint and won't pull apart.


Corey

BMRisko
01-24-2005, 04:42 PM
Rotate the heim 90* or you'll be blowing out joints every week/

robselina
01-24-2005, 05:43 PM
this is the only way i could think to make the upper adjustable, but it doesn't seem like it will be nearly strong enough to hold up:

http://img.photobucket.com/albums/v123/gearhead313/upperdesign2.jpg

yea, definitely don't do that. Better to have the adjustment in the A arm itself, know what I mean? It would serve two functions that way.

oh yea, also, it won't work unless you have a LH and a RH thread....

As for the mount that's existing on the axle, post a pic. I'm betting it would be pretty easy to rotate the heim 90 degrees...

Timzjatl
01-24-2005, 06:04 PM
If you don't turn the heim, you will rip them up in very short order (a matter of weeks)... The side loading on that design is tremendous. Trust me, I ran what you are showing above, and killed 2 heims in a month (chromo, expensive ones) so I flipped the heim and had no more problems for the life of the system.

I dont understand how that positioning of the heim will so affect its life span. There shouldn't be any difference in side loading between the two. Both ways, with a lateral load on the axle will be on the bolt the same.....pulling it in either direction. I also think the force on it (other than longitudinal axle wrapping cycles) will be lessend with properly placed lower control arms. Please let me know what I probably have wrong in my thinking. Again, the axle is so nicely setup this way, I really hate to change it.
The side load that would normally be taken out by the trackbar will be focused on pushing the ball of the heim out of the casing. Heim's aren't designed to be loaded this way, and as such you'll blow the little ball right out of the casing. Trust me, I've done that.

ATL ZJ
01-24-2005, 06:16 PM
If you don't turn the heim, you will rip them up in very short order (a matter of weeks)... The side loading on that design is tremendous. Trust me, I ran what you are showing above, and killed 2 heims in a month (chromo, expensive ones) so I flipped the heim and had no more problems for the life of the system.

I dont understand how that positioning of the heim will so affect its life span. There shouldn't be any difference in side loading between the two. Both ways, with a lateral load on the axle will be on the bolt the same.....pulling it in either direction. I also think the force on it (other than longitudinal axle wrapping cycles) will be lessend with properly placed lower control arms. Please let me know what I probably have wrong in my thinking. Again, the axle is so nicely setup this way, I really hate to change it.
The side load that would normally be taken out by the trackbar will be focused on pushing the ball of the heim out of the casing. Heim's aren't designed to be loaded this way, and as such you'll blow the little ball right out of the casing. Trust me, I've done that.

Exactly what I was thinking. You want your bolt perpendicular to the force to prevent damage to the joint. In the case with this A-arm assembly, the force would be lateral, rather than vertical. The bolts article by Billavista in the new Xtreme Offroad (actual good magazine with real tech) outlines this very well.

gearhead313
01-24-2005, 07:22 PM
Thanks for the replys on that, i understand now how thats affected. I just never thought that there would be 'that' much force on it when the triangulated lowers should take up some of that force.

Ya, i know the threads need to be opposing...i just forgot to show it in the drawling. I definitly stick to the first idea also.

I'll get a pic of the axle whenever I can find my camera.


...my thoughts are, why did the previously owner of this axle have it setup like it is if its obviously not the correct design. I know this axle was in a buggy for almost a year before he parted it out. Maybe i'll try to get more information on his setup.

gearhead313
01-24-2005, 07:46 PM
here are the best pics i could get of the axle with my video camera:

http://img.photobucket.com/albums/v123/gearhead313/zj%20pics/IMGA0074.jpg

http://img.photobucket.com/albums/v123/gearhead313/zj%20pics/IMGA0075.jpg

http://img.photobucket.com/albums/v123/gearhead313/zj%20pics/IMGA0076.jpg

http://img.photobucket.com/albums/v123/gearhead313/zj%20pics/IMGA0077.jpg

OverkillZJ
01-24-2005, 10:23 PM
You're right, you're not flipping that heim 90 degrees!

gearhead313
01-25-2005, 10:24 AM
You're right, you're not flipping that heim 90 degrees!

see what i mean, and how nice that is.. :(

gearhead313
01-28-2005, 01:12 PM
After getting educated, it seems that its going to be manditory to flip that heim on its side. Its just a matter of designing the axle mount then going from there.