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lupinsea
07-30-2008, 03:13 PM
Just a heads up post on my recent "fix" for my Jeep. I'll often contribute write-ups on other Jeep boards and while I know it's not too applicable to members on this board I figured some might be interested just for interest's sake.



Lower Control Arm Bracket Reinforcing


CONTENTS

1) Vehicle Setup
2) Overview / Performance Review
3) Installation


1) VEHICLE SETUP

No other modifications are necessary to perform this procedure and installation. It will work with stock or modified Jeeps.



2) OVERVIEW / PERFORMANCE REVIEW

Overview:
After 4 years and 50+ offroad outings the control arms and mounting brackets on my Jeep needed repair. The control arms were bent and one smacked by a rock so badly the pressed in bushing came loose. The bracket ears on the frame were dented and crushed to the point they interfered with the control arm movement. All this resulted in wonky and vague handling and disconcerting clanking and creeking noises from the suspension.

Solution:
In addition to replacing the control arms with new(er) used stock control arms, the brackets on the frame were straightened and reinforced with a 1/4" rod shaped to a flange and welded in place. The lower axle brackets were boxed in with a mini-skid plate. This protected the end of the control arm from rocks and greatly strengthened the lower control arm brackets. Total cost for the project has been approximately $20-25 in steel, spray paint, and consumables.

Performance:
While no impact testing has occured I feel confident the reinforcing flanges and mini-skids have significantly beefed up the brackets. In the case of the weld-on flange rod the edge of the frame brackets have tripled in thickness. And by boxing in the axle brackets the chance of the bracket tabs getting knocked askew is virtually eliminated by the skid acting as a shear brace.

Road testing the new arms and straightened brackets has been great. All the clanking and creeking noises have disappeared. The handling and ride has improved as well and it feels like I have a new Jeep again. This exercise has certainly been worth the time and very modest expense.

Leasons Learned:
A few aftermarket companies make pre-bent and pre-cut front axle bracket skid plates for approx $25 tha are ready to weld. For a modest cost these save some hours of measuring, cutting and shaping of the steel. Were I to do this over I would have purchased a set of the pre-made weld-on skids as a time saver. The rear axle bracket skids are easy enough to fabricate out of flat bar stock and take significantly less time to make These I'd definitely recommend fabricating yourself.



3a) INSTALLATION - FRAME BRACKETS

Tools:
Use of a welder, angle grinder are critical for this project. In addition, a pipe wrench made an excellent bracket bending tool. ratchet straps help suck the axle back into place making control arm re-installation easier. A dremel tool is needed for close-quarters grinding and cleaning of the front axle brackets. Beyond these is just basic mechanics tools.

Note:
Remove one control arm at a time. The remaing control arms help keep the axle located.

Preparation:
The process for the frame brackets are the same front and back. Note how damaged and misshapen the frame bracket is (Fig 1). Remove the control arm (Fig 2) and assess the bracket. Using the pipe wrench (Fig 3), place the jaws over the bent bracket ears and re-bend. This is a very controlled way to re-shape the bracket compared to smacking things with a mallet. Also, the control arm bolt was reinserted and snugged down to keep the bracket ears aligned during bending. Note how straight the bracket ears can be reshaped to (Fig 4.). Finally, use the angle grinder to grind off the paint around the welding area as well as de-burring the outer edge and reshaping any lumps.


http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_01.jpg
Fig 1. Front frame bracket was severely bent and distorted along with the
control arm which was also replaced.



http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_02.jpg
Fig 2. Remove control arm and asses bracket



http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_03.jpg
Fig 3. Using special tool #3489, carefully re-bend bracket ears into
original shape. One of the suspension bolts was reinstalled to help keep the
ears from spreading during the re-bending process.



http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_04.jpg
Fig 4. The re-straightened bracket.



Flange Fabrication:
With the ears now straightened, hold up a piece of cardboard and trace the outline of the bracket (Fig 5). Using a bench vice and mallet shape a piece of 1/4" steel rod to the profile traced on the cardboard (Fig 6). Once you get the hang of it the shaping process doesn't take much time. Test fit the flange against the bracket (Fig 7). Due to the factory facets in the bracket you'll need to fine tune the flange so it sits flat on all the facets.

Note: Be sure to allow for sufficient clearance around the bolt hold for the bolt and washer/nut.

Lastly, weld the new flange to the bracket by first tack welding it down, then welding both sides of the flange rod (Fig 8). Make sure the flange extends up to the frame and overlaps with the ramped portion of the bracket.


http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_05.jpg
Fig 5. Using an angle grinder, remove the old paint and get down to
bare metal for welding. While at it, grind down any burrs or protrusions.
Then trace the profile of the bracket onto a piece of cardboard for a
template.



http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_06.jpg
Fig 6. Using the template and a precision bending machine, bend the
1/4" steel rod to the shape. Keep the shape of the rod "inside" the outer
edge of the bracket profile you traced.



http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_07.jpg
Fig 7. Test fit the new flange rod. Some tweaking will be required to
ensure the rod fits flat against all the bracket facets.



http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_08.jpg
Fig 8. Weld the flange rod onto the bracket. this tripled the edge thickness of the bracket ears.



Clean-up and Finish:
Using a wire wheel, wire cup thingy, and/or steel brush clean up the weld area for painting (Fig 9). Lastly put on a couple coats of paint for protection (Fig 10). In this case I used an industrial quality Rustoleum, black. After a few runs it'll dirty up again and blend in with the rest of the frame.


http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_09.jpg
Fig 9. With the wire wheel and steel brush hit the bracket to get rid
of any welding residue and clean it for painting.



http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Frame_10.jpg
Fig 10. Spray on a couple coats of good paint to protect the steel
from corrosion and rusting. Don't worry, after a few wheel'n runs the fresh
paint will get dirty and blend in with the rest of the frame.





3b) INSTALLTION - AXLE BRACKET MINI SKID PLATES

Preparation:
Like the frame brackets, re-bend then grind/clean the area to be welded (Fig 11). The use of a dremel tool is invaluable for the front axle brackets as thre are a number of places it's hard to manouver the angle grinder to.


http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Front_01.jpg
Fig 11. The front axle bracket takes a lot of hits on rocks and can
benefit from having it boxed in with a mini-skid plate. This will help protect
the end of the control arms, too.



Measure:
Carefully measure where to place the front skids. For this project I found the skids run nearly parallel to the front bracket edge but are held out nearly 1" so the end of the control arm will have sufficient clearance. Also, determine where to weld the skids on to. In this instance I welded the new skids to the outer face of the existing bracket. Some scraps of cardboard are useful for making mock-ups, just cut and bend the cardboard to get the desired shape. A 2 ft x 3" piece of flat stock is sufficient to fabricate all four axle brackets.

Cutting and Shaping:
With the necessary measurements I cut and shaped two pieces of 3/16" x 1" x 1" angle iron to form the sides of the mini-skids. With the angle inverted this gave me a flat area to which I could weld the main 3/16" x 3" flat stock piece. A vicegrip clamped the main skid and side angles together to help with a pre-weld test fit.

Welding:
Next the various pieces of the mini-skid were welded together after proper alignment and test fitting. Once the skid was ready it was welded to the axle brackets (Fig 12).


http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Front_02.jpg
Fig 12. The mini-skids after welding the pieces together. Ready to
weld to the axle bracket



Clean-up and Finish:
Lastly, the final cleaning and painting put the final touches on this project (Fig 13).


http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Front_03.jpg
Fig 13. The new skids welded to the front axle brackets and painted.



Rear Brackets:
The rear brackets are much simpler to make since there are no side-skirts needed for control arm clearance. (Fig 14)


http://homepage.mac.com/jgreening/.Pictures/Jeepmods/LCA%20Bracket%20Reinforcement/LCA_Back_01.jpg
Fig 14. The rear axle brackets were much more straightforward to
fabricate. Just bend the end of a 3" wide plate and notch at the bend for it
to fit between the bracket ears.

misterlance
07-30-2008, 06:50 PM
Nice. I remember the noises those control arms made. ;)

rautox
07-31-2008, 08:11 AM
I'll be interested to see how the bracket reinforcement holds up, Lup'.

*welder jones*

lupinsea
07-31-2008, 02:07 PM
Certainly. Sometimes I wonder if I should have welded on a thicker flange. But after whacking the frame bracket ears pretty hard with a mallet they seem solid. We'll see. I think they'll do fine.


I just came across some other cool ideas such as cutting and re-welding my gas tank skid to tuck it up ender the Jeep further (increased ground clearance / departure angle). Cost $0.00.

And I've come up with a superior mirror relocation bracket to move the side mirrors off the doors and onto the windshield frame such that they retain the stock spring / detent mechanism. There some units already on the market but they stick out about 1.5 - 2". My design would only project out about 3/8" and be much stronger. Cost in steel ~$4 or less each bracket.

I want to do the mirror brackets soon but I'll wait on the gas tank skid modification for later. I won't be doing any wheel'n in the Jeep for a few months at least. . . why bother starting a new mod.

operknockity
07-31-2008, 02:45 PM
Certainly. Sometimes I wonder if I should have welded on a thicker flange. But after whacking the frame bracket ears pretty hard with a mallet they seem solid. We'll see. I think they'll do fine.

I'd have thought you would have reinforced the base of the ears better, too. Maybe run that reinforcing farther up a few inches.

lupinsea
07-31-2008, 05:28 PM
The back "ramped" portion of the bracket is boxed in, a u-shaped piece. Welding on material there wouldn't have done much as its already very stout. And looking at the damage to the brackets that was already sustained, it all occurred on the thin "ears". The back portion was still rock-solid and un-dented.

It was the rounded "ears" that were unsupported and crumpled over.

Let's see. . . Ok, take a look at the first picture. It's a bottom-up view of one of the brackets. The top of the photo is toward the rear and the bottom shows the control arm toward the front. Note how the steel bracket is shaped in a general box or u-shaped. There's a lot of strength at the corner and it didn't seem necessary to continue the flange too far up the corner. As it is, it goes half way up.

operknockity
07-31-2008, 06:30 PM
Only thing is, now that you've reinforced the ears, if you sustain new damage, the weak point is now the section between the reinforced ears and where the ears mate with the box.

3LOU5
07-31-2008, 07:18 PM
If you keep modifying that Jeep, pretty soon it'll end up looking like this:

http://www.hprcc.unl.edu/nebraska/Dscn0134sm5.jpg

:lol:

lupinsea
08-01-2008, 03:14 PM
Only thing is, now that you've reinforced the ears, if you sustain new damage, the weak point is now the section between the reinforced ears and where the ears mate with the box.

I think it'll be pretty good for the trails and terrian I run. If I were rock crawling it'd be a different matter. But I mostly run forest trails. This damage occurred on some trails I wasn't used to that had a lot of hidden rocks below the surface mud.

lupinsea
08-01-2008, 03:15 PM
If you keep modifying that Jeep, pretty soon it'll end up looking like this:

http://www.hprcc.unl.edu/nebraska/Dscn0134sm5.jpg

:lol:

MMmm..... tempting. But mine would be yellow.