Colinb17's kinda sorta build thread - now with 4-link and long travel

Really liking it!
1/2" seems a good size if you want one size to fit everything from small harnesses to larger winch power cable. I'll probably order some 1/4" as well though for the real small stuff like tail light wires and ABS sensors. excited to try out some of their other products.

natural shape



held open



mock-up with three 14 ga wires



mockup with some shitty winch power cable that came with one of my winches years ago. not sure what gauge it is, but i always swap out for a size or two larger, which this loom should also fit just fine.

 

cutting out the 1/4'' frame plates to finish up boxing the frame from the rear-most crossmember under the cab, back to where the frame is chopped. the little notch tucks under the crossmember allows the plate to extend all of the way to the crossmember and weld to that as well.

 

I have a bunch of wires in my truck, and my car that both need some re-looming. This will be the way.

 

rear frame plating complete, and the rear of the sliders tied into the frame. was able to get away tithe the foot of unsupported slider for a long time, but with the main hoop attaching to the slider, it needed to be done. the forward portion of the frame will get reinforced as well, but that will likely happen after the additional crossmembers for the links are complete, if not at the very end, after the truck is drivable. it's a very important step for beating on the truck off road, but not critical for getting it up and running.

next step is to mock up the link cross members and get some PVC links hooked up. then i can test all of my clearances on the cab/frame at full compression, and confirm that pinion angle and plunge are consistent with the original calculations throughout the suspension cycle.

 

This is going to be one stout rig! I like the triangulation.

 

How's that HOA been?

 

So far so good. We've had a lot of visitors the last few months to see the baby, and they typically don't realize anything is up when they walk up the driveway right past it.

 

Makes it sound like they don't have as keen an eye as we do.

 

Looking good

 

today was very fulfilling. got the links mocked up with PVC and the link locations (frame side) mocked up with some scrap tubing tacked into place. The hours of measuring, spreadsheets, and math paid off, and the suspension cycled exactly as planned on the first try. I trusted the math, but wanted to mock up anyway before cutting and drilling the expensive 2''x.25''wall DOM. it also allowed me to test clearance on what remains of the the frame, and confirm what the up and down limiting factors will be.

at full compression, the limiting factor is the driveshaft contacting the underside of the cab. at full drop, the limit is the driveshaft u-joints (pinion angle is where it should be). there are of course some ways around both of these limits, but i'm hitting my planned travel numbers without them, so no need.

between both limits, vertical wheel travel is 25''. bumped and strapped, i'll be limiting it down to about 22''. the photos with the tape measure below show 26.25'' from bottom of drum to concrete where i plan to have the bump bottom out, and 4.25'' from bottom of drum to concrete where i plan to have the limit strap stop things (stretch factored in).

also tested out articulation to make sure there were no link contact issues. vertical separation was adequate. it will articulate more than the photo shows, but i ran out of Jack, and the heat index is 115 degrees here today, so i wasn't feeling rigging up the engine hoist.

First photo is the truck at ride height, which will be roughly 1'' of lift over stock. strapped and bumped, this yields 12'' of compression and 10 inches of drop.



photos of full bump.









photo of full (strapped) drop.





drop and bump measurements.





There's more articulation, but I ran out of jack. pleased with how little horizontal axle movement/rear steering there is under articulation.

 

Got the link tubing cut down based on the PVC mockup. Need to put a decent bevel on the ends and drill some plug weld holes before welding in the rod end bungs.

Cage tubing vs link tubing.
1.75"x0.120"
2"x0.25"

Definitely the most expensive steel I've had on the band saw.

 

Got all 4 links cut, prepped, welded and re-tapped based on the mockups. pretty simple overall, but tedius when every step has to be done 8 times.

after cutting, I put a decent bevel on the ends for weld penetration, and then tossed them in the self centering drill press jig to get the plug weld holes for the threaded bungs. 4 holes per end, two at 1'' offset and 2 at 3/4'' offset. started each hole with a center drill, and then finished with a 3/8'' bit.









machining on the bungs was nice and tight, so really no precautions were needed to ensure they were in the tubing square asside from a quick check with the anglefinder.

for welding them, i laid 4 tac welds half way between each plgt weld hole, and then laid a TIG root pass with 1/16'' filler. the root pass was made in ~1'' beads, jumping around the bung.




After the root pass, i MIG welded the plug holes. intentionally took the plug weld about 1/8'' proud of the surface of the tubing. more on that in the next few photos.....
i then cap welded the bung. TIG again, but with a 3/32 filler. again, jumping around the bung with 1'' beads.




after letting them cool, it was time to re-tap the threaded bungs for the rod ends. one left hand and one right hand thread per link.

Been using anchorlube for a while. fantastic stuff for drilling, tapping, notching, and band saw cutting. its a water based paste, so it stays where you put it vs the oils that get absolutely everywhere. water base makes for an easy cleanup too. only thing you have to watch out for is if you're drilling at higher speeds, you can fling it off the bit.
anyhow, you can see how well it works to prep your taps with. available at TMR customs, Amazon, etc. I bought the little applicator bottle and TMR, and a big refill jug on amazon.



some people opt for bungs with a hex end on them that you can put a large adjustable or open end wrench on. I opted for smooth bungs, since after a few wheeling trips, dragging the lower links across the rocks, those wrench ends are so banged up, you pretty much have to use a pipe wrench on them. I'm not a big fan of pipe wrenches, since the teeth digging into the bung or link itself will cause stress raisers that can lead to cracking and tearing. also does a number on them from a paint standpoint and you have to repaint after each use. these links in particular are way overbuilt for my application, so stress raisers really aren't a threat, but I still don't like the principle. instead, a good strap wrench will do the trick. going back to those plug welds, by making them 1/8'' "too tall" they also give the strap wrench more grip. not critical when re-tapping the threads, but will certainly come in handy when torqueing down those jamb nuts that have a tendency to loosen up.




this might be a little nerdy for most, but the benefits of the weld process I outlined for the bungs was very intentional. when welding threaded inserts like that, with enough heat to get good weld penetration, you will essentially always get shrinkage, so best practice is to plan on re-tapping them afterwards. frightens me a bit that there are a lot of people just accepting that their rod ends take a ton of effort to spin into the bungs after welding them in. with the low end taps of this size running about $60 a piece, make sure it's planned in your build budget for $200 with or taps.

if your welding procedures play out well, you will get a little shrinkage, but no warping of the bungs. you can tell if you have warping or not by the consistency of resistance on the tap, and what the cuttings look like. As shown in this photo, long, thin cuttings show general shrinkage with a very small amount of material being removed around the entire bung. You also have a very constant resistance on the tap. if you have warpage, you will feel "tight" and "loose" spots as you turn the link on the tap. the cuttings will be much shorter, only cutting where the bung warped inward. the downsides to a warped bung, are that you're getting good thread contact where the tap is cutting, but less than desirable contact were the "loose" spots are. when most links catastrophically fail, its the rod end being pulled out of the bung, so maximum and proper thread contact is important.
you can see the long, thin cuttings on top of the tap in this photo.




going back to expensive taps (and tooling in general).... the water based cutting lube is super easy to clean up, but MUST be cleaned up or else it will rust your tooling. I wipe most of it off with a shop towel, and then a quick spray with wd40 removes the rest of the residue. quick spray with acetone removes the wd40, and then you can protect the tooling with 3-in-1 oil, or whatever you'd like before storing it. my go-to is Boeshield. Created by Boeing, and used by a number of manufacturers, primarily on their landing gear for corrosion prevention. this is also what I'll be spraying the bodies of the King coil overs with to attempt to protect them from out salty air here.





Slightly less related to the truck, these two XX chromosome individuals have been the reason for this build to move so slowly. As much as i can't wait to make Truck memories with them, i can't miss out on the current memory making opportunities. hope everyone had a love and freedom filled 4th of july/weekend

 

Lol ...... 723 ft*lbs on this guy

 

Hopefully you've got a 10' torque wrench haha

 

I've got an engine hoist and a 2000 lb load cell. Just have to math it up based on how long of a wrench I hook onto the end of.
May send a wrench into orbit, but we'll meet spec!

 

Was hoping to hold off on the full frame plating and reworking until the truck was on its own 4 wheels again, but as I got further into it, it just didn't make sense to delay. So 2 days later, and we're nearly complete with the plate work.

Started by plasma cutting the bottom flange of the frame from the back, up to front cab mount area. Just shy of 7 feet long. Replaced the double layer of thin gauge steel that's occasionally riveted together, with a single piece of 1/4" plate. Also wide Ed the flange by about a half inch. Wrapped the same 1/4" steel 3 inches up the side of the frame on the outside. Fully welded from both sides, and the outside plate integrated well with the slider's scabbing plates.

Now finishing up boxing the inside with more 1/4"" plate. Math says I've added about 150lbs of steel so far, likely cresting the 200 lb mark once I finish from the carrier bearing cross member, forward. Fortunately all 200 lbs is below the COG, further lowering it. Frame is becoming quite rigid, even without the tube work. It'll make for a louder passenger experience, but really allow the suspension to be tuned without frame flex muddying the waters.

Too hot out to spend much time taking photos, so here's one of the plate between the carrier bearing cross member and what is now the rear most cross member at the back of the cab.

 

Yes, yes, yes.

 

What's the benefit of a torque spec being that high on that jam nut vs say torqueing it to 200ftlbs and calling it a day?

 

Can of worms question! I'll try to be brief, but complete enough to make sense.

It's all about the yield strength of the rod end at that point. Realistically, I will never (hopefully) be able to put enough force on the rod end to require the 700 ft*lbs, and a couple hundred will be fine.

But the science behind torque value on a jam nut is that the rod end has all kinds of directional ratings. The jam nut is concerned about what happens under tension. Under the maximum allowable tension, the rod end will stretch (temporarily) "x" amount, as calculated and/or measured in a lab. The jam nut needs to have at minimum, the same amount of tension preloaded onto its threads when torqued. If it does not, then at the exact instant that the maximum tensile force is achieved, the jam nut will become loose, until the rod end returns to its original length. With these links being so overkill, I could make the assumption that at 2/3 of the maximum rod end rating I will actually tear the frame apart, or something along those lines. So if I cannot physically reach the maximum allowable rod end rating, then as you suggest, there is no need for the stated torque spec.

The question then, is what is enough? So without doing an absolute ton of measuring, modeling, and math to determine what the maximum load they'll see is before the truck tears apart, I have two options. Lower torque spec, and monitor to make sure they don't come loose, and if they do, increase the torque until they dont.....or torque to 723 and not have to think about it.

Ultimately what this all boils down to is that tension in a threaded system is really what matters, not torque. Thread tension can only be measured with a load cell though, so instead of putting mini load cells (tension washers) on everything we do, we use torque, a derivative of tension, that can be measured by a wrench.