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As I mentioned to Gavin above, I'm just starting to educate myself on what can be done, Perry. I originally thought I might be able to repurpose the donor brake lines, but they have many bends in them and are pretty hard material. Unbending them, which is what I'd have to do, isn't practical.

I bought a roll of CuNi (I think they call it CupraNickel or something like that) line which can be bend by hand if necessary, although I have a simple bending tool also. That line is going to run inside the tunnel. I have welded in tabs to mount it already and have the mounting clips too.

The part I have to reason out and plan is the segment from the chassis proper to the brake calipers. Until I had all the moving parts in place (photos will be posted today) it was hard to visualize where the simplest, safest place might be to place the join of the flex tubing to the chassis mounted tubing.

I haven't got a plan yet, but I'm in shape to make one after I educate myself on ways to do it, and where it needs to go to stay safe.

The Anti-moan plates (I think of them as Slut-plates, which tells you a lot about my mentality) were an add-on somewhere in the SN95 development process. Under maximum braking, the Mustang brake mounting flange tended to flutter and moan. They were an after-the-fact way to solve the problem without modifying the rear axle itself. You've implicitly asked the right question, Perry, "Will they still be necessary?" I don't know the answer, but my inclination is to make sure I can modify them in future should they be necessary to have them, but leave them off for now. I may just modify them, but leave them uninstalled. I go back and forth on that because it is so much easier to work on the axle now versus after it's on the road.

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Thanks for the ideas on this. I may get back to you with some questions later. It's a new area for me.

Thanks very much,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

I guess I'll start with the "bottom line" from yesterday's work. I have all the components, or their stand-ins, in place now. Here's an overall photo. I finished in the evening, so the sun was pretty low, and the photo isn't all that clear - too many shadows.

Here's some details:




I put everything into the standard "neutral behaviour" setting. The control arms are parallel and horizontal. The Panhard rod is horizontal and also at right angles to the centerline. I estimate the roll center is about 6".


I knew some components would be a tight fit, and have to be installed in a particular sequence, so doing the fit-out showed me what that would have to be. I had two surprises. It turned out the faux coilovers needed to be set at 12-1/8" instead of the 12" indicated in my 3D model. Meh! The second one will actually require some action.

At about 1-1/4" of bump, the tire sidewall barely makes contact with the upper control arm bolts. I've planned on 3" bump as my upper limit, so that's an issue.



I did use a different bolt and washer setup than the original design. It sticks out about 1/4" more, and that's just enough to cause trouble. I've thought of three solutions thus far: 1) back to low profile bolt heads, thinner washers; 2) 1/4" spacers for the rear wheels; and 3) move the axle back 1/4" by adjusting the control arm lengths. The last one has the most consequence as it slightly change the rear suspension (arms, Panhard, coilover angle/length). I've got some time to think it over. It's just going to rolling around in the garage for a while - no bumps.

Generally, I'm quite happy. No serious issues have shown up. It's the first car I've designed, and given that, it's turning out pretty well so far.

Cheers,

_________________
Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

When cornering, and with the low tire pressure, the tire is going to deflect maybe an inch laterally.

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Kurt, you could be right. However, it's hard for me to visualize that with these tires. They are very low profile, with really stiff sidewalls. If it is true, I have 3 tools (at least) to work with. All three could be used, if necessary. For example, moving the axle back 1/2"; low profile bolt heads; plus a spacer should give the distance needed.

Also, I could look at a V2 adjuster to move the bolt forward. The driveshaft, rear anti-roll bar, etc haven't been made yet, so no loss there.

Cheers,

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Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

This might be a stupid suggestion (if so, apologies) but could you reverse the bolt so that the larger head is on the 'inside'...?
Maybe you don't have sufficient space to insert the bolt from the rear...
This idea won't help much but, added to one or two of your options, might just give that little extra clearance you need.

All three sound good to me, individually or in combination. I don't think moving the axle back a quarter inch would give you any driver-detectable problems, but hey, I'm a street guy nowadays and haven't had the seat of my pants recalibrated since '74.

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Locost builder and adventurer, and founder (but no longer owner) of Kinetic Vehicles

No that's not a stupid suggestion at all. In fact, the mounts are made to work that way. The thing that changes is that the chassis side is no longer adjustable. It's fixed in the traditional Locost 4-link configuration: control arms parallel to each other and to the road surface. It's a good, simple solution with "neutral steer" at the back axle.

Here's a photo with that setup. The bolt protruding is too short because it was just a trial to make sure the threads were clear and working from the back.

Thanks for the suggestion.

Cheers,

_________________
Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

Thanks for the "Amen" on that, Jack. I've made everything adjustable, so altering the axle location isn't hard. A 1/4" change won't really make a significant difference in suspension performance.

Cheers,

_________________
Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886

If the bump was one wheel/roll from lifting one side, the hardware, a trim to the sleeve/outer bush length/inner spacer, and 1/4 wheel spacer may be all you need.

If this contact was from lifting both ends of the axle, then you may need to do more to ensure clearance in roll.

The adapter could be shortened and tapped instead of using a nut and washer on the inside to save about a 1/2 inch. You'd need to offset the rear of the link in the axle brkt the same amount if retaining the bushing at the front instead of going with heims on both ends.

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Lonnie, looking at your pics I'm assuming that the axle assembly is centered? Pan hard rod adjustment takes care of that. Low profile bolt head and wheel spacers would be my fix.
I'm liking that button head bolt picture MV8 posted.

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Perry

'If man built it, man can fix it'
"No one ever told me I couldn't do it."
"If you can't build it safe, don't build it."

Perry's Locost Super Che7enette Build
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I've got nothing constructive to add. I do have just one question. Do I detect masking tape painted over? I think it would be stronger if those frame tubes were welded together rather than just taped. But then again, I'm no degreed engineer. Maybe you've done the analysis. I wouldn't want you to have a Hempy event.

I'm Just kidding of course (OR IS HE?).

Maybe that is what the "W" is for in black Sharpie (JD, I found one that got away), a quality control inspection tag for rework. Yeah. That is probably what it is.

BTW, Looking good.

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Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766

I actually just had a constructive thought. Along the lines of MV8's cap screw. if you have access to a lathe, you could turn a new top-hat shaped washer like the pic below. That way the cap screw would be completely below the washer's face giving you even more clearance.

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Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766

I had the same idea as Chuck. And I think it will give you the most space when utilizing the bushing mount.

Another idea that I had is to utilize rod ends on the upper control arm. It would buy you a good bit of space. My guess for this idea to work well, is that both ends on the UCA would need to be rod ends to avoid binding of the busing in the axle. You could build a spacer or use misalignments spacers in the rear to take up the room in the axle mount. I think this counts as option #5

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Gavin

My build: http://www.locostusa.com/forums/viewtopic.php?f=35&t=16005

@MV8
@horchoha
@rx7locost
@Mnot

Thank you gentlemen for all the ideas. I'm going to take a look at all of them. I'll answer your questions, though.

It was a one wheel bump that developed the interference problem. The rear axle is as centered as I can make it with hand measurements using rulers and a tape measure. Yes, the W's are to remind me to weld the joints when I dismantle the chassis for the final time to paint it. I decided I'd rather do good flat welds later, rather than do poor out of position welds now.

The good news is that there is certainly a solution. Just the button head bolt and a simple spacer would get me a lot. My near term goal is to get a roller and get it off the build table. I still have two biggies to do: front suspension design/build; and the back end of the car. I'll switch to those two now and work on this issue in the background.

Thanks again, I do appreciate the help.

Cheers,

_________________
Damn! That front slip angle is way too large and the Ackerman is just a muddle.

Build Log: viewtopic.php?f=35&t=5886