Joel's multipurpose XJ build (rocks/boulevard)

Found a possible answer on the bump stop engagement.

http://www.fourwheeler.com/how-to/0904or-bump-stop-tech/#photo-08

When installing urethane bumps, consider that they may compress about an inch or more and set your dimensions with that margin in mind. Bump stops with integral air gaps will compress even further than solid urethane ones.

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Unless anyone else has more specific feedback I'll likely set mine at 1" plus the full height of the cutout window (another 3/4" maybe? need to measure) before shock bottoming as my starting point.

A few questions still outstanding above.

I highly recommend you plate the frame around the bump stops if they're going to get used. I had those, plus some extensions off the axle tube to hit the stops. It eventually started buckling the frame around the bump stop. I've since removed them and plated the whole frame, but I'll be doing something else for bump stops.

trippled said:

I highly recommend you plate the frame around the bump stops if they're going to get used. I had those, plus some extensions off the axle tube to hit the stops. It eventually started buckling the frame around the bump stop. I've since removed them and plated the whole frame, but I'll be doing something else for bump stops.

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Roger that. I had one bolt on each side seize/shear on disassembly, so I was thinking it might be easier to cut those out with a hole saw and add a plate back in with heavier nuts welds. Sounds like that idea just became dual purpose.

Got a picture of your axle tube extensions? What's the new plan for bumps?

No pics. They were basic, just square tube welded on. Worked really well. Not sure what I'm doing yet tho. In the midst of a big overhaul on it, but I'm going to look for something a bit more progressive. I found the day stars to be super hard if you ever hit them. Which if I was loaded down, happened a lot.

trippled said:

No pics. They were basic, just square tube welded on. Worked really well. Not sure what I'm doing yet tho. In the midst of a big overhaul on it, but I'm going to look for something a bit more progressive. I found the day stars to be super hard if you ever hit them. Which if I was loaded down, happened a lot.

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Makes me wonder if I should look into shaft bumps as a first stage with the daystars as a second engagement. Sounds like I'll have to play with these a bit.

Anyone have thoughts regarding building bastard packs? Again, these are the two I'll be combining and I'm looking for 1.5-2" lift if I can.

trippled said:

No pics. They were basic, just square tube welded on. Worked really well. Not sure what I'm doing yet tho. In the midst of a big overhaul on it, but I'm going to look for something a bit more progressive. I found the day stars to be super hard if you ever hit them. Which if I was loaded down, happened a lot.

Click to expand...

Makes me wonder if I should look into shaft bumps as a first stage with the daystars as a second engagement. Sounds like I'll have to play with these a bit. Thanks for the heads up.

Anyone have thoughts regarding building bastard packs? Likely going to tackle that tomorrow. Again, these are the two leaf packs I'll be combining and I'm looking for 1.5-2" lift if I can.

I’m way behind on these updates but at least I’ve been making some good progress so here’s some more info.

Frame Stiffeners… supposedly key to XJ longevity. Since I decided it was worth upgrading my Jeep a bit more, I bought the full front/mid/rear kit from HD Offroad Engineering.
http://hdoffroadengineering.myshopify.com/products/xj-frame-stiffener-set Reviews on fit were good. I likely the goldilocks “just right” thickness at 0.135” and the time savings having someone else burn and bend these easily justified the cost. Plus it's cool to support someone who's really focusing on the XJ.

Downside was that I’d screw up the width of my fancy mid skid since that bolts in from the sides.




I’ll have to fix that to install stiffeners but still went for it.

The stiffeners ship bare (no box!) tack welded together in two bundles with labels stuck on random faces. It kinda seemed chincy, it kinda cracked me up, but they still arrived without damage so I guess it works.

Started prep by drilling out the 6x skid plate points per side. I was planning to reuse the hole positions but wanted the stiffeners in tight to the rails and was worried what might happen if these gloried rivet nuts ever failed and spun.






I ended up with 9 jackstands supporting the vehicle. 2 on the gas tank skid, 2 big 12 ton jobs on the front bumper, 2 on each axle, and one for the transfer case.



The BDS transmission subframe was left in place, dangling down. I took this up and down a bunch of times doing trial fitments. It dangles by the weld nuts as it would have to slide in above the frame rails if you took this all the way out.

Pro Tip: Don’t drop a lower control arm on your head, especially a long arm. 9 stitches (3 internal) and a tetanus shot later…



Funniest moment in the ER. My wife grabbed a book and is reading to us while we transition from the various waiting rooms. Didn’t think about it, but we happened to be re-reading on of the Harry Potter books. Talk about dudes with FAMOUS FOREHEAD SCARS! I was laughing for a while after I realized that, even while they were trying to sew on me.

Ok, back to the project…

Grabbed some remnant stock from work and sliced up a bunch of little disks so would have some proper threads to engage into by tapping this after the fact. Used magnets to hold it while I burned them in and felt clever with my forethought (more on this later).






After I ground these most of the way back flush, I moved over to prepping the actual stiffeners.

Fit was quite good but could be improved ever so slightly. Rear of the mid stiffener was notched with a 1/4" step on both sides to clear the leaf spring mount.




I also notched around the two frame rail gussets on either side. Here’s my estimate.




One of the rear stiffeners was missing a couple rosette holes so I added those back in. Grinding disc made a decent circle cutting guide.




Last comment would be that I took about ¼” off the top curve to the left of my gusset notches. Actually both top and bottom radii could be larger but I wasn’t going to add material back in. Not sure if these were late model changes (I’m a 1999), but I’ll try to get this to HD Offroad to see they want to make some subtle improvements.




Did a few rounds of bending in appropriate places to optimize fit since tack and hammer fitment only gets you so far.




All stiffeners and frame rails also received a healthy dose of weld through primer before I burned these in.




Here was the last trial fit and you can see what I meant about the radii.




Last thing to do was to add the holes for E-brake cable tray and my specific trans subframe. That’s not that interesting so I didn’t stop to grab a picture.

All in, I was still a pretty happy camper as I got welding. Rare mug shot, because I liked the mad scientist hair (this was at some point before I smacked my dome).




Notes on welding next...

frijolee said:

Grabbed some remnant stock from work and sliced up a bunch of little disks so would have some proper threads to engage into by tapping this after the fact. Used magnets to hold it while I burned them in and felt clever with my forethought (more on this later).

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ive seen many drill bits ruined when trying to clean up a plasma cut hole. the heat locally hardens the area. hope it works out for you. atriot:

VAhasnoWAVES said:

ive seen many drill bits ruined when trying to clean up a plasma cut hole. the heat locally hardens the area. hope it works out for you. atriot:

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Very astutely observed... Emphasis on my original statement is that I felt clever (past tense). The holes I cut via plasma were for welding so that was fine. Hell even drilling and taping welded mild steel was do-able.

The mystery steel bar stock I pulled out of rem stock? I thought about whether it might harden in welding but it cut fine on my band saw (bi metal blade, nothing crazy) so I thought I'd be OK.

Turns out, not so much... but I think you already know where this is going.

ahhhh yes, good ole' mystery steel.



love the belly skid BTW.

frijolee said:

Pro Tip: Don’t drop a lower control arm on your head, especially a long arm. 9 stitches (3 internal) and a tetanus shot later…

Funniest moment in the ER. My wife grabbed a book and is reading to us while we transition from the various waiting rooms. Didn’t think about it, but we happened to be re-reading on of the Harry Potter books. Talk about dudes with FAMOUS FOREHEAD SCARS! I was laughing for a while after I realized that, even while they were trying to sew on me.

Click to expand...

I did similar....but it was one night ~ 3 am as I was getting ready for a run.....no one around to help or take me to ER.

Mine was not a long arm tho....it was the rear driveshaft from a lifted 79 dodge ramcharger (see my avatar).

I had just swapped from a NP203 to a NP205 tcase...and when I went to put the DS in to see if it fit, I put the rear ujoint in the pinion yoke, then held the shaft with my right hand as I stretched it to put the ujoint in the tcase yoke with my left hand. Guess what....the NP205 is shorter...the splined joint in the DS came apart, and the long/heavy end covered in grease and gunk came down and smacked me about 1/8" above my right eyebrow, giving me a nice gash about 1 1/2" long.

I was VERY lucky it didn't hit my eye, and that it didn't do any more damage than it did.

It just gave me a massive headache, and I stopped working and missed the ride that day. Never did get stitches, or even go see the doc over it.

Still got a scar to this day, and that was over 20 yrs ago.


.

TRCM... That does sound similar. Mine 10 pm or so, working alone on my driveway. It wasn't quite lining up so I was wiggling it up there and it got away from me as I repositioned hands. Quite thankful I didn't knock myself out or I might have been bleeding for a while.

Post a pic of your scar! I'm curious.

Thoughts on welding frame stiffeners.

1) Don’t even both trying a tig welder (too many gaps and overhead work jammed against rails and/or the floorboards). Probably obvious, but worth stating.

2) A 110 V mig is plenty for these, I blew through the frame rail twice as it was (frame rail is thinner so it’s not hard to do). I’m using a little Millermatic 135 on the bottle and it kicked ass and took names.

3) I also used a big wire wheel to get things close and then only removed paint with a flapper disk at each point I planned to weld. I’m really doing all I can to keep this healthy long term and sandwiched metal can be a corrosion risk. Then it all got wiped down with denatured alcohol prior to the weld through primer (U-POL #2).

4) I started from the middle using a combination of a floor jack and 2x4 from below and C-clamps from the sides. On the first rail I started jumping every three holes, but having looked at how far the heat affected zone goes I don’t think concentrated heat is much of a problem for the rosettes.




I experimented with a few different methods and sequences of burning. I found that if you just weld in a spiral from the middle all the way out to the stiffener the rosette hole is large enough that you can blow through the rail. To be fair, I was welding pretty hot. It also can end up with a pretty big weld (more to grind later).





Doing this on jackstands sucks. Sitting on the ground left my head banging against the rocker at eye level and it was hard to see without putting your spine in a pretzel to get low enough. I got a little lost on one...





The best technique I worked out for the rosettes was this:

1) Start with a ~2 second pulse in the middle of the rosette hole. It’s just welding on the rail at this point but it’s building up and getting things hot (especially helpful when there’s any kind of gap between rail and stiffener.

2) Pause long enough for the glow to get back to kind of a dark cherry red. Maybe

3) Do a finish pass tracing the classic MIG cursive letter “E”s around the perimeter of the hole tying stiffener to the build up you made a few seconds ago.

After doing the side rosettes I added the stitch welding along the edge. Some folks claim you don’t want to weld the whole edge else as its good to have some frame rail maintaining parent material strength. Made sense to me so I stitched the seam between every other rosette hole. On the stitch welds I did do two passes from end to end to keep the heat moving around (every other stitch on each pass).




I basically did 100% of each vertical face on the mid stiffeners before moving to the bottom surface. On the bottom fact my rail had a few dents that formed a little gap in places. The horizontal leg is also pretty short. As such, here I stitch welded first (and got my 2x4 smoking a few times in the process).




By the way, if you do blow through the frame rail while welding on the bottom surface it’ll drop a decent size blob of molten metal so you do NOT want to be directly underneath this thing, it’s just too easy to do that.

If you do drop a blob of molten metal on your driveway, when you go to weld up the hole you just made, you may or may not notice that you just set the driveway on fire next to you. Not that I’d know anything about that… Just saying.




Very last area I did was the gaps for bending on the mid stiffeners. Brian (HD engineering), nailed the placement on these. I used a filler pass on rail only to shrink the gap a bit and then did a full pass swinging back and forth all the way to the edges welding uphill. Seemed to work out pretty well.



By the way, the rosette weld on the right in the pic above is a pretty good example of what I was shooting for. I did grind all the rosette’s back to flush since I need a relatively flat surface to tie my big skid plate back into. I’d picked up a big dog 8” angle grinder at a garage sale a while back and used the heck out of that thing. The masking tape at the top helped avoid getting shavings behind the stiffener. I’m planning to use seam sealer after I get it painted.

Expect the ground to be pretty furry with shavings by the time you’re done grinding.




Front frame stiffeners tuck behind the front bumper side plates so I’ll need to move my jack stands before I tie those in. Process should be the same.

A little late, but The best way I have found to rosette weld stiffeners is like this:

Think of the rosette like a clock face.

Start at 9 and work backwards in time to about 3 (lefties would probably want to do the opposite) basically welding the bottom half. Keep most of the puddle on the stiffener.

Once you've welded the bottom half of all the holes, turn your voltage down just a touch then work from 12 o'clock down to 3 and then 12 down to 9.

Depending on the size of the rosette hole you may need to spiral the middle to fill in.


On the overhead stuff, an exceptionally clean surface helps a lot, but welding overhead is never easy. Especially on the thin sheet metal of an XJ unibody.

frijolee said:

TRCM... That does sound similar. Mine 10 pm or so, working alone on my driveway. It wasn't quite lining up so I was wiggling it up there and it got away from me as I repositioned hands. Quite thankful I didn't knock myself out or I might have been bleeding for a while.

Post a pic of your scar! I'm curious.

Click to expand...

HA....not much to post now it seems.

I just checked in the mirror, something I ain't done in many years, and I don't really see it anymore. I guess it finally went away, or is hidden now due to the old man bushy eyebrow thing that's starting to take hold.

And only where the scar was too.....wierd.

And back then, no camera phone, so no pics of the damage either.

rockclimber said:

A little late, but The best way I have found to rosette weld stiffeners is like this:

Think of the rosette like a clock face.

Start at 9 and work backwards in time to about 3 (lefties would probably want to do the opposite) basically welding the bottom half. Keep most of the puddle on the stiffener.

Once you've welded the bottom half of all the holes, turn your voltage down just a touch then work from 12 o'clock down to 3 and then 12 down to 9.

Depending on the size of the rosette hole you may need to spiral the middle to fill in.


On the overhead stuff, an exceptionally clean surface helps a lot, but welding overhead is never easy. Especially on the thin sheet metal of an XJ unibody.

Click to expand...

I like the fact this approach deliberately addresses the effect of gravity and the puddle sagging when you're on vertical faces. On my second pass, I generally did a full circle from 3 o'clock, clockwise back to the start. I also lingered a bit at 12 o'clock help address puddle sag.

Was the goal of focusing puddle on the stiffener based on the thick/thin rule to help penetration? I think I was trying to address the same prinicple: by welding the middle of the hole first, the second pass ends up tying between two surfaces that are now closer to the same thickness. I suspect the impact of thick/thin might be greater on thicker stiffeners.

The one I'm not so sure about in your description, is adjusting the welder mid pass. Do you have some sort of torch control? I had two solid evenings of welding into this as it was and my welder lives on a cart. No way could I see climbing up and down every twice for every rosette to dial things up and down. As it was, just lying on my back for the overhead stuff, I ended up using a chunk of 4x4 and folded towel as a pillow just because my neck was getting tired holding my head up that long.

The jerry rigged pillow might have been why I was so comfortable and kept going when I set the driveway on fire... My wife laughed at me. Wasn't the first, probably won't be the last time. :yelclap:

I'll try out your notes on the front stiffeners and compare. Thanks for posting!

the focusing on the stiffener is for better penetration since they are thicker.

as far as adusting the settings, I only do it once for every section.

I do all the bottom half Rosettes, adjust the welder and finish them.

I only do that particular step because I am using a lincoln 180v and it runs pretty hot, I find myself burning through once the unibody is nice and hot and I'm welding on a veritcal plane.

Rockclimber, good stuff, thanks for clarifying.


Moving on, here’s the story on those frame rail steel plugs that didn’t work want to thread as planned.

Sometimes when you’re pushing hard trying to get something done you make decisions that come back to haunt you. Sometimes shortcuts work out OK. Sometimes you think you can get away with more than you can. I’ve often told non-car people that wrenching on cars is about overcoming the unexpected difficulties that crop up. Whether it’s the rusted bolt you just broke, or the part that didn’t quite fit like expected, you can never productively finish projects unless you can find a way to overcome those challenges.

I knew I’d set myself up for some pain, drilling 12x holes through ~1/2 steel by hand. That’s not easy nor particularly fun no matter how you slice it. For drilling steel I like using about 1/8” bit. Bigger and it’s too slow. Smaller and it’s too easy to break bits pushing with enough force to get it to cut (and not just smoke the bit).

First four pilot holes drilled OK. I was using basic Harbor Freight Titanium Nitride Bits (their basic machinist set). Hole 5 gave me a bit of a challenge, had to break out the drill doctor. It was still kinda slow cutting so I reached for the small set of Dewalt split point bits I had and drilled all other 8 positions without too much difficulty.

Whew, hard part past I’m thinking… Now that I have pilot holes I should be in the clear. Jumped up to an "H" sized bit (Ti Nitride again) as I’m only planning to tap for M8 bolts and they don’t have to be huge. Again first four holes drill fine. 5th hole… Will not cut. Drill doctor again, make sure the bit is perfect, plenty of cutting fluid, varying pressures, varying speeds. Will not cut.

I’m not ready to give up so I head over to HF and buy their machinist cobalt set. Those weren’t out when I originally bought my other ones a decade ago. Yes, you can get stuff that’s more bad ass, but I’m pretty careful and I’ve had decent success using their stuff in the past. Cobalt set still runs $110 in drill bits, they're a little brittle but good in a pinch.

Take it back home and manage to drill all the holes. #5 on driver side is still the sticky spot but at least I prove the drill doctor works on cobalt bits too. Split point on that bit gets a bit shaved down in sharpening but I can live with that. Any time I’m reaching for a cobalt bit this big I’m going to have a pilot hole already.

OK, time to tap this thing.

I’m up again the bottom side of the rig, but I figure out I can use a square drive socket and wrench to apply torque with good force and still keep the tap stable and straight. Definitely going to use this trick again...




Again first four holes go OK. Takes some significant torque to cut but it’s working. I can feel it start to bind up so I’m reserving regularly to break my chips. I have Tap Magic cutting fluid dripping off this thing… Basically I’m doing everything right that I know of.

Hole 5:




Back out the tap and it's fubar'ed about as deep as I cut... Dammit. Couldn’t feel the difference between cutting threads and the plug ripping the teeth off my Craftsman tap… What the F was this metal? The stiffener itself cuts like butter by comparison.

So I take the bar stock I used into work and we break out the hardness testers.




Exterior of the bar measures 27 HRC. That’s not mild steel but it isn’t too ridiculous. Head machinest sends me home with a bad ass tap, supposedly rated to 45 HRC and some Castrol Moly Dee cutting fluid. We also talk about opening up the pilot holes a bit to make things easier.

I get home and drill all the hole out to a “J” without much difficulty. I start using the bad ass tap… chase the first four holes and get some decent crap cleaned out of there.




Hole #5, get it started… IT’S CUTTTING! I’m being as smooth as I can be… I just start to feel the chips loading, I hear the tiniest of cracking noises, so I go to reverse… and promptly break off the tap in the hole.




Well, I’m not fitting an EDM under my car to burn out a tap and/or cut threads. I’m doubting this is tappable at this point… and I owe my machinest a $30 tap. Screw it I’m done. Sometimes, you can overcome the difficulties, sometimes you have to know when to cut bait and run. I’ll just have to add fresh holes in a different position.

I wish this story had a happier ending, but for the moment it’s mostly a cautionary tale. I was just pushing too hard to keep things moving that a shortcut in material choice burned me bad. Live and learn.

I was frustrated enough that I couldn't stand tapping another hole and I moved on to other things...




-Joel

So now that I’ve added frame stiffeners, here comes the skeptical part… Everyone swears by frame stiffeners but it always seemed to me like a really inefficient way of adding torsional rigidity to a unibody. On the one hand I know that a cage tied into the roof pillars would be orders of magnitude better, but I’m trying to keep this family friendly.

My XJ already had welded rectangular tube at the rockers, but I’ve heard of folks who’d hit down hard enough on these to collapse the body above. As such I decided that if I was going to do frame stiffeners, the least I could do would be to tie in the rockers and end up with more of a ladder structure on either side of the body rather than discrete parallel stiff elements connected by only sheet metal. This was the plan from first ordering frame stiffeners so I did it immediately following.

I started into this planning to use two 2x2s and two 2x1’s stingers on each side, with the 2x1’s allowing me to keep enough clearance to the prior hole pattern for the big aluminum mid skid.

Plasma cutting w/ guide.




Cleaned up and ready to bend ends inward.




Not shown: welding the angles, adding drain holes, and a quick shot of weld-through primer on the insides, but here they are burned in. Slightly larger spacing up front than for the back three to clear my BDS transmission subframe bits.




Since I was abandoning my planned mid skid hole locations (see drilling/tapping fiasco posted above), I ended up making a few more of these stingers and running the equivalent of 2x2s everywhere.

My rocker is 3/16” wall which is a little more than my MIG is supposed to be used for. I used a MAP gas torch to preheat the rail and was happy with the penetration and results.