Builds fj60 going to EV FJ45 (1 Viewer)

[workingdog]

Okay, I'm back to the rear suspension. I knew I'd be here eventually when it was time to think about the flatbed.

I got talked into going from 12" to 14" coilovers, and in the rear it was a mistake because it shoved the coilover tower way up into the flatbed. Plus ... the way this thing is laid out, I can't take advantage of 14" coilovers, with 5" of up travel max, there's no way I can make use of 9" of droop, 7" is fine. So 12's work great (really, 10's would probably serve). That should bring the tower down to level with the top of the battery box, which means the flatbed will be high, but it will work.

So, now, I'm ripping the rear coilovers off for like the 4th time. (Doing something twice is bad enough but this is getting ridiculous). I set the frame at what felt like a good ride height, just a little higher than the front, and looked under and I only had 2" of up travel (and yes - why did I put the brakeT there when clearance is such an issue? Fortunately it's easy to move). So, I took the rear back up 2 more inches. And then I started thinking - and that's when things always go down hill.

The limiting factor on the up travel are the link mounts on top of the rear axle truss. They sit just (and I mean just) behind the battery box under the grey box which is the high voltage charger. Now, the high voltage charger could move and I could put a hole in the steel plate across there so that the link mounts could travel another 1/2" up, but the links would hit the battery box pretty soon anyway, so I can't get much.

But then, the idea that occurred to me a few days ago that I could rotate the battery box vertical. The batteries don't care. Run the main BMS cable out another side. The HV connectors wouldn't even have to move. It would require notching out the flatbed big time, but the flat bed could then sit a little lower. The big gain is that I'd probably be able to gain 2" of up travel by letting the diff and the upper links sink into that area. I'd have to messwith the supports ... but that's doable.

This gets the frame down at a reasonable height (19 to 20"), while getting more up travel. But, getting more up travel with the frame lower pushes the coilover tower back up.

so, here's my original problem. I want the tower down at the height of the black battery box.

Here's my clearance issue underneath. Those two bolts you see coming down hold the charger in place, that's the areaI'd clearance - after I get the brake stuff out of the way.

Here's a view from the side

Here is what I'm thinking of doing.

 

[workingdog]

My son's brilliant suggestion is to just put the battery box on the flat bed and then figure it all out later. That might be the best solution.

 

[Ragnaroek]

Maybe you should go back to leaf springs in the rear...

What about moving the charger and pushing the battery box up another 2-3"? The bed would end up pretty high, but then there could be enough room in the rear to mount the spare wheel between the frame and the flatbed and incorporate some toolboxes/storage left and right of the battery box.

 

[DangerNoodle]

Lol, 12" rears is where it's at. Rotating the battery seems like a pretty good solution.

 

[workingdog]

I really want the flatbed here to see how it sits. The one I want won't be here until April. But, those are all options.

 

[workingdog]

Okay, re-did all the numbers on the rear. The battery box is up in the air so it's not an issue and the plate is removed. So, here's a video of my stuffing it and getting about 2" more. So, with that and 5" of up travel, I can cut the coilover tower down about 1". Not nearly as much as I hoped. But, it is what it is.

When I get the towers tacked in place, I'm going to put it back to full stuff and then tack the bumps stops in at that actual height. No math.

I'm going to need to figure a way to keep the battery box where is it while I'm test driving, I guess just a couple of ratchet straps.

And here it is at ride height

 

[workingdog]

Okay, the towers are in for the 12" in the back. they are higher than ideal, but I think we can stuff a flatbed on top of them. The battery box is way high for now, and I'll have to wait and see if I can get it low enough to go under the flat bed while still keep all the up travel I want/need. And ... I happened to have the right springs and it settled right to ride height. I think it's a pair of 15's - one 12 and one 14. When the bed goes on, I may have to swap one to 175, we'll see.

And this time, when I put the coilovers in, I put the spacers in. I figured out to build a little do-dad that would keep the spacers in position while I get the coilover into position. There is no to hold onto one spacer, let alone two, and get the bolt in the way the ends of the coilover are dished out (concave). But that wouldn't work on the bottom, so I used the do-dad to locate the spacers and used my little LED plastic welder to weld the spacer into position long enough to get the bolt in. I'm going to have to see if I can get slightly wider spacers.

 

[workingdog]

Here's the latest test drive with windshield, roll cage, 12" coilovers in rear. with the windshield, you can hear the horrible gear whine. I'm going to have to chase that down. I'm playing with my phone to make sure the gopro is recording, all I succeeded in doing was stop it recording. This makes it quite clear the steering wheel isn't in the right orientation - damn.

 

[workingdog]

Update:

Swapped HV cables to the driver's side so the primary disconnect would be easier to reach. The required flipping the battery box bottom for top. Could not just spin it as the connectors would up on the back. Moved coolant to passenger side.

2 days of fun to fix a minor annoyance.

Battery box up on wood so I can get at it - 850 lbs of fun.
turns out these connectors are going to be right behind the main support for the flat bed. So, I'm almost certainly going to have to take this side off and move them as close to the bottom of the box as I can get.

part way up, had to reset

Not now using second chain hoist to control rotation, almost up

Up

And down on the other side.

Coolant from controller now out passenger side, cool pump rotated down 90's for better hose orientation and easier priming of pump.

New HV connections on drivers side.

New disconnects of coolant on battery box.

New disconnect location on driver's side, farther out so that it's accessible when the flat bed, which will be out where the slider is, is in place.

 

[GLTHFJ60]

I love this build, but damn man, this is an exercise in trial and error.

Have you considered modeling any of this stuff in cad? It'd be a bunch of hours to model it all, but I feel like you'd find a lot of these conflicts before you start installing.

Not trying to throw shade at all. You're the first individual I've ever seen try to build a crawler ev. I absolutely love it, and could see myself building one too. Tons of respect, but is there a better way to figure out how to make this all fit and work together before you spend money on fab?

 

[workingdog]

I did try to model the suspension in 2D in the beginning, and it was a waste of time. But, even if I'd taken the time to learn solid works - which I might still do, my son is about to learn it - my problem is I didn't have the experience to know how to compare the tradeoffs of travel versus packaging versus etc., etc., etc.. One of those tradeoffs I slowly been prioritizing more and more is to get the thing as low as possible. Getting it lower finally convinced me to go back to 12's and redo the battery position so there's more up-travel into the frame so that the frame can sit lower. I had no clue about the realities of that when I started.

Certainly, putting the HV disconnect on the wrong side was just me not thinking when I did it originally - which was driven by the face that it was just a frame and I didn't have the tub or seats to kind of orient me. But, things like getting talked into 14's is totally my lack of experience. I took the advice to heart. But once I did the math, I realized that there was no way this rig (ladder frame, flat bed) could take advantage of the 14's - and the 14's caused all kinds of different problems.

I've learned I have to actually see and touch something to be able to feel in what feels okay and what doesn't. And the height of the flat bed (or having holes in the flatbed for the coilover towers) was one of those things I've been trying to get a handle on for over a year. One of the reasons I've decided to build the flatbed myself is so that I can work through it as I go, and because it's going to have to work around what's there (battery box, coilover towers). My son said 'but it won't look nice and professional'. Well, nothing on this car looks professional.

One of the main reasons I took the project on was so that I would have to work through every single facet of putting an off roader together and learn all those trade offs that are so important. I've still not gotten the rig over 40 mph. I should have registration in a month of so, and then I'll be able to drive it down to the store and I'm sure that experience will prompt a whole bunch more changes.

For instance, one of the things I got originally talked into was connecting the motors together and using a transmission and transfer case. I still think that was the wrong approach. I think it should have one motor driving the rear axle and one driving the front axle. But, I haven't done all the math to figure out how just the gearing would work, let alone how to package the front motor so it will drive the front axle, and now a center drop front axel would work better (and I can lose the panhard?) - and I'm not sure if the Hyper 9's will be okay with the slave motor going on and off. (although it could just stay on). So, eventually I may attack that. That would save ... 300 lbs? Which is 10%, that would be a big deal. I'm far from done.

Another thing I realized recently is that I'm doing all this on 35's I don't intend to run. So, I finally ordered some 40's (still nothing good available) so that I can actually do all this at the right height and be able to look at if something rubs are not. That could cause a bunch more problems.

But, the thing I really, really miss the most is having someone in the shop with me to just talk about this and that. Without that kind of back and forth to get different options and walk through alternatives, I end up down rabbit holes that I should never have headed down.

 

[workingdog]

The aluminum for the flatbed has arrived.

But I can't do anything with it until I get the new tires on, and I can't get the tires on, and I get take the wheels off until I turn the EV around so that I can also put spacers on the front coilovers while it's up in the air. And I can't turn the EV around because it's throwing and error indicating it can't read the spin sensors.

It can't read the spin sensors because these connectors

apparently spontaneously lose connection. It ran fine last week, but this week throwing the error on startup. When this happened months ago, the guy I bought the motors from told me the connectors have a tendency to do that. So, I took them apart and put them back together and zip tied them up - and it's been good. But now it's doing it again. And, given how buried they are now (unlike months ago) and the fact the error makes the rig dead in the water. I have to come up with a better solution. So, I think for now I'm just going to rip them apart and convert them to crimp on spade terminals or a simple screw terminal block. I can't see any reason why that won't work. Going to be a huge pain where it is, but ... I can't think of a better solution. It's this kind of stuff that drives me crazy. All this vehicle held hostage by a 50 cent connector. Also, I can't believe they are just losing contact. how could that be?

But, if I can the EV to move, this weekend I'll have the EV on 40's and I'll be mocking up the flatbed.

 

[archie73]

The aluminum for the flatbed has arrived.

View attachment 3170042

But I can't do anything with it until I get the new tires on, and I can't get the tires on, and I get take the wheels off until I turn the EV around so that I can also put spacers on the front coilovers while it's up in the air. And I can't turn the EV around because it's throwing and error indicating it can't read the spin sensors.

It can't read the spin sensors because these connectors

View attachment 3170062

apparently spontaneously lose connection. It ran fine last week, but this week throwing the error on startup. When this happened months ago, the guy I bought the motors from told me the connectors have a tendency to do that. So, I took them apart and put them back together and zip tied them up - and it's been good. But now it's doing it again. And, given how buried they are now (unlike months ago) and the fact the error makes the rig dead in the water. I have to come up with a better solution. So, I think for now I'm just going to rip them apart and convert them to crimp on spade terminals or a simple screw terminal block. I can't see any reason why that won't work. Going to be a huge pain where it is, but ... I can't think of a better solution. It's this kind of stuff that drives me crazy. All this vehicle held hostage by a 50 cent connector. Also, I can't believe they are just losing contact. how could that be?

But, if I can the EV to move, this weekend I'll have the EV on 40's and I'll be mocking up the flatbed.

Man I’d love to go ev on my f100, but between my lack of knowledge in terms of ev and these set backs you’re having, I’m not sure I’d be up for the challenge. Good on you for keeping it going!!

 

[workingdog]

Oh, don't think your experience will be like mine.

And, I got under there to replace the connectors and the wires just came out in my hand. and these were pins that were snug when I made them over a year ago. And now they just fell right now. Not good. I put little tiny wire nuts on them for now and it's working again.

 

[workingdog]

Okay, got the spacers in the coilovers. Could not get the parking brake to work.
But, I got the 40's!!! Little tight on the front fender. but it certainly changes the look.

My math on the rear slider length wasn't quite up to stuff.

and now the coilovers are done and the charger is mounted again and the battery box are the right height. I put some of the decking on to see how it sits.

 

[workingdog]

Okay, the high voltage connectors were definitely not in the right place once I put the main flatbed support in place.

So, picked up the battery box one more time (I have racked my brain about a mechanism for lifting the battery box that's easier than ratchet straps and can't figure one out) and relocated them lower.

And I replace the spin sensor connector with a DIN connector. It's easy to operate, a very positive connection, can be mounted and dismounted easily. And if I need to remove the controllers, the motors can stay connected.

 

[workingdog]

So, the main longitudinal stringers are roughly in place with wood. I think I'll end up doing box tube and rubber matt for the final installation. The lateral strings are just set in place. The 2x2 is 1/4" wall, so they are beefy. And then the decking on top. Right now it's 72" by 72". that's as long as it can possibly be, and the same width as the sliders. So, it's a big square with about 1/2" clearance above the battery box and the towers.

I mean, it will work. I was looking at it if it needed to be narrower or shorter, but I think it's fine, the departure angle is fine and consistent with the bumper (which is not kind of buried). And the width seems fine, a little wider than the cab, same as the sliders, a couple of inches narrower than the outside of the tires. Should be pretty easy to attach fenders.

The decking overlaps and locks together and almost every piece of the overlap is bent or dinged, so there's some time there cleaning that up. And I'm not exactly sure how to secure it. I can rely on the over lap (in fact, I could just cut if off). I'm going to have to secure each piece to each 2x2. I'm checking if the deck manufacturer has a clip I can use. The way this stuff is made, it's not easy to toe screw it.

 

[DangerNoodle]

Can you weld it? Would probably be the easiest.

 

[workingdog]

I could weld it, but then it's never coming apart. Although I could just tack/spot weld it.

Also, I need help figuring how to attach the main stringers to the frame. I could use u-bolts over the C-channel or I could just drill holes in the C-channel and bolt it to the support, but I don't know if I need to allow for more movement than that. Same with welding the decking, as the hole thing flexes, I don't want it to tear the flatbed apart.

 

[DangerNoodle]

I could weld it, but then it's never coming apart. Although I could just tack/spot weld it.

Also, I need help figuring how to attach the main stringers to the frame. I could use u-bolts over the C-channel or I could just drill holes in the C-channel and bolt it to the support, but I don't know if I need to allow for more movement than that. Same with welding the decking, as the hole thing flexes, I don't want it to tear the flatbed apart.

I would think some light tacks till you can fully bolt it would make it way easier.