LocostUSA.com

I welded my ball joints in. 3 stitch welds around the bottom, easily scored and popped out if they ever need a change. 4130 has so little chrome in it that it’s not really a chrome family classification in the welding world. Weld it with ER-90s and your good. No pre or post heat needed.

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Steve

My build : http://www.locostusa.com/forums/viewtop ... 35&t=17160

MGB/GT V8 5.0L. viewtopic.php?f=36&t=20782

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Cheers, Tom

My Car9 build: viewtopic.php?f=35&t=14613
"It's the construction of the car-the sheer lunacy and joy of making diverse parts come together and work as one-that counts."
Ultima Spyder, Northstar 4.0, Porsche G50/52

He's back!

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Peace, Ron

If you're welding 4130 to mild steel, ER70 is fine. The filler will still be stronger than the mild steel side of the joint. I've welded a fair amount of 4130 to mild steel with a MIG - no issues. The most difficult part is when you're using thinner wall 4130 tube and having the heat correct.

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-Andrew
Build Log
Youtube

I now have both sides of the Lower Control Arms done in CAD. It's been tricky because the suspension analyser program I use (which has all the accurate distances) has a completely different coordinate system that the CAD program. So, I had to lay it out common to something between them like the build table plane and the roadway plane at ride height.


My first set of QA checks look good. Of course the proof is in the pudding, which means a part constructed on an accurate jig, that fits the brackets on the chassis. The latter two are the really hard parts. I'll start figuring out the jigs next although I'll probably reverify the CAD measurements with the actual chassis before I finalize it.

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

I need to tilt my LBJ too, in order to clear the taurus wheel bearing while placing the ball as far outboard as possible to minimize the scrub and KPI.

Are you using the K772 or K727? My LCAP brkts are the adjustment method on the spitfire. I’m offsetting the LBJ a ½ inch forward on the LCA to provide some caster without adding shims to one side of the LCA that would tilt the coilover at the LCA attachment and cause the LCAP bushes to not be on the same axis.

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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12

@MV8

I often get the numbers mixed up, but my upper is the K772 upper, and my lower is a modified version of the K727 lower. It's shaft is shorter than standard to get my spindle closer to the ground for better positioning of the lower control arms.

At the time I started my project, I wasn't aware that due to the light weight of these cars, the smaller K772 is strong enough to be used as the lower as well. The K727 was a better match for my Mustang spindles, however.

Last night I realized I had left out the the reinforcing gussets at the outside edge of my ball joint plates where they bend. I'll probably wait until they're done as shown, and do a "field upgrade" then.

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

Your planning is impressive! Can hardly wait for the next stage of construction.

Thom

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Thom

@BostonWill

Thank you, Thom.

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

I concur Thom.

If Lonnie can tear a Vette dash out, wring out the electrical issues, put it all back together, pass the inspection, I'm sure fabbing up a couple or four control arms is going to be a piece of cake for him!

Yes I can hardly wait for the pics.

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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
Perry's TBird Based 5.0L Super 7 L.S.O
Perry's S10 Super 7 The 3rd
Perry's 4th Build The Topolino 500 (Little Mouse) Altered
Perry's 5th Build the Super Slant 6 Super 7
Perry's Final Build the 1929 Mercedes Gazelle

@BostonWill
@horchoha

Thanks for the vote of confidence, guys.

However, I've found it's easy to make a bad, inaccurate part, and hard to make one that's correct and precise. I now approach these things with great humility and reverence. And, then I end up making a bad part anyway [LOL].

Oh well, I do try my best, and sometimes that turns out to be pretty good.

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 post will be a smattering of things. I'm going back through my notes and schedule getting familiar and confident with the data I developed before my multi-month layoff from the Locost project. I looked at my lower ball joint notes, and felt they were vague.


The lower ball joint assemblies have 5 components in all if you count the Zerk fitting, but it comes apart easily for measurement, which is what I wanted to verify by doing again, and improving my notes.


I did make some drawings of the bent plate for the lower control arm. It occurred to be it would be a good piece for the local waterjet outfit to cut in 3/16" steel, and then I'd only have to bend it. I got a quote, and it was reasonable, but they couldn't get to it for 2-1/2 weeks. So, I'm going to do it by hand.


Fortunately, my HP printer/plotter is accurate enough to do a 1:1 drawing, glue it on to cardboard, and use it for a pattern. I just center punch the holes out using the pattern, then drill them out based on the center punches. That's why the holes are not cut out.


I'm going to try an interesting approach to the lower control arms. I could spend a lot of time building an accurate jig, but I think I can build them in place. I have some very accurate wooden bases that hold the spindles at the correct ride height even without the tires mounted. The ball joints disassemble for easy viewing and placement (me thinks) of the ball joint center locations at the correct distances in X,Y and Z. The critical measurements are placement the ball joint center locations and the length of the control arm from chassis bushings to ball joint center location. I won't go into a lot of detail, but I think I can do it in place.



I like to noodle around with stuff and put things in place to try them out. I found the rear, upper suspensions bushings were rubbing on the bracket. They are the two shallowest of the 8 brackets. With the bolt in and tightened, the bushing collar made pretty tight contact with the bracket and was tough to rotate.

So, I put the bushings in the lathe, and turned down the bushing collars about 0.040 and they fit much better, and turn readily when the 1/2" bolt is tightened.

The fit is pretty decent now. The other 6 brackets do not have this issue.


So, that's it for now. I need to go out and find some hole saws to drill the 2-1/2" hole for the weld-in ball joint ring, then trace out, fab and bend the LCA bent plate. Tomorrow's a half day, though. It's Super Bowl time tomorrow afternoon. Go Rams!

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

I started on the DOM bushing sleeves. I've measured each of the 8 locations and figured out what I believe will be the best width for each location. The bushing maker gives a generic width, 1.320". However that's too wide for some locations, and too narrow for others. I only want a couple thousands of play between the bushing material and the bracket steel. Just enough so there's not undue friction, but not enough to let the control arms move much under braking, steering, etc., etc.

So, I ended up with a list, and I'm just marching through it. The DOM material is very heavy duty, but is what the bushing manufacturer recommends.


I ended up cutting two different widths. I'm facing off one end, then trimming down the other end to the desired width using my mini-lathe.


It was interesting getting things set up. It requires a lot of concentration since several widths are required, but I kind of got into it and it became somewhat meditative. This is the first completed DOM sleeve.


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

Looks close in size to 1 inch schd 80 pipe. I like schd 40 pipe for shells and sleeves after machining the small weld rib out of the id. These spit arms are just rolled tube, unwelded and much thinner wall.

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Miata UBJ: ES-2074R('70s maz pickup)
Ford IFS viewtopic.php?f=5&t=13225&p=134742
Simple Spring select viewtopic.php?f=5&t=11815
LxWxHt
360LA 442E: 134.5x46x15
Lotus7:115x39x7.25
Tiger Avon:114x40x13.3-12.6
Champion/Book:114x42x11
Gibbs/Haynes:122x42x14
VoDou:113x44x14
McSorley 442:122x46x14
Collins 241:127x46x12

It is really thick material. One of my questions is about welding to it joining the 1" DOM tubing that will actually make up the arms. It's got to be enough heat to penetrate the thick bushing sleeves, but not too much to blast through the 1" DOM material.

Questions, questions [SIGH].

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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