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Discussion Starter · #143 ·
Now there are 4 A-arms and two push rods ready to be welded and heat treated. The sphericals locations will be bored out to after to allow for any distortion during heat treatment. The rod ends will come last.





I still need to make the upper mounting brackets or plates to allow for double shear on the bolts. After that it's upright / knuckle work. At the very least, when these are done it'll go a long way towards making me feel like I've had some real progress after such a long time.
 

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Discussion Starter · #144 ·
Welding time!
I had a friend and a friend of a friend come over to my place and get the A-arms and pushrods welded up. He has a lot of experience (training and job) and knowledge (degree) in materials / materials joining so really it was a no-brainer when he agreed to help with these. He has a new, water cooled Tig setup from Miller and was happy to have a project for it again.

Since the parts are 4140 and 4130 that I bought in the annealed state and I want to get them heat treated, he hunted down some 4130 filler rod instead of the typical ER70.. or ER80.. type filler. This would allow the weld area to be more uniform with the base metal and be able to be heat treated to the same levels instead of the ER series wire.

So... on to pictures.
I used my oven to get the parts preheated to 400F to help ensure the weld areas in the alloy steels wouldn't later crack. We then locally heated the weld areas with a MAP torch before welding began.


He welded all of the tube ends first. Notice the safe attire haha. He said it's the first time he's welded in sandals but not the first time in shorts. We experienced record breaking heat this weekend in Seattle so I couldn't blame him. Molten metal might have felt cooler with the humidity and heat we're not used to (typical 70s or 80s and it hit almost 110 at my place this weekend)


All the tubes were stuck in a bucket of sand to control the cool down rate after the ends were welded. When those were cooled we started the pre-heat cycle for the tubes to the machined lugs. Weld. Sand cool-down.


Final results!


I'll drill the pushrod holes after heat treat and bore out the spherical bearing holes to their final diameter to account for any shift or deformation during heat treatment:






I just dropped off the parts to a local heat treat shop (ok, a business that does large castings, machining, and heat treatment) that agreed to put my personal project in their flow since I asked for a fairly typical heat treat level of 150-160ksi.

Now it's a waiting game for them to anneal, heat treat, and temper before I can chase the threads in the ends and finish machine everything. In the mean time I'm finally getting back to moving the Bridgeport base in place to re-assemble that.
 

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Discussion Starter · #145 ·
Progress on two fronts recently...

First, the Bridgeport is finally getting assembled in position!
Base first


Then knee, turret, and ram. This accounts for a majority of the 'heavy' items. Once I replace the bearing in the knee that goes over the lifting screw, I'll be able to get the table put on. The head re-assembly will follow all of that.


Now for the front suspension update:
The arms and pushrods are back from heat treatment. At first I specified a minimum strength of 160ksi (160,000 lbs tension capability per square inch of material cross sectional area). I didn't specify a maximum because that was a fairly easy target to hit. I figured it'd come back around 180ksi. Turns out they figured they could skip tempering and that resulted in almost 240ksi. Way over the minimum so technically they met my requirements. Since stronger equals harder which equals less elongation and more brittle (in a relative sense, not like a ceramic brittle), I asked them to temper it lower. In the end it came out to 200-215ksi depending on the 4130 tubing and 4140 lug. Still has good elongation to prevent cracks due to bumps or road hazards but still strong enough to give me extra safety margin from what I calculated originally.


In this picture you can see where they removed the scale after quenching so they can do hardness testing (and calculate strength based on that). Look close and you'll see multiple, tiny dimples from the tester on the end and on the tube.


The dark arms are after heat treat, tempering, and quenching. The light is after a soft sand blasting to get the scale off. I don't think I'll polish or powder coat the arms but I will probably clear coat them after I solvent clean the outside to keep the metallic look but prevent rust on the alloy steel.


Next up is boring out the lug ends for the spherical bearings and grooving them for a snap ring. The lowers will also have the hole drilled for the pushrod rod end.
I'm also starting on the upright parts for the spindle, brakes, steering, etc.
 

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Insane amount of talent and work.. thanks for positing.. learning from every step.. :)
 

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Discussion Starter · #147 ·
Thanks northshore2014! Glad you like it all!


Onward with the latest

I did a quick test fit of the A-arms on the chassis and I think they'll work pretty well once I get some proper spacers/parts made to take up the gap between the arm lugs on the chassis and the rod ends. This will also be one of the ways I can adjust the caster in the front even though I'd rather the lower arms stay relatively fixed due to the pushrods connecting there.


The upright has also made progress with the LH/driver's side one. I started with a billet of 14lbs of 7075 aluminum and started machining away.


Mid progress before flipping:


The end result is an upright that weighs 5lbs, 2oz. Not super duper light but considering I'm doing hand calcs and conservative estimates (I hope haha), I don't think it's too shabby. If anyone wants to weigh the front spindle Factory Five provides to compare, feel free to post the weight of that.


Finally, this is the configuration of the front suspension including the upright, hub, brakes caliper and rotor, steering bracket, etc. There's still a few 3d printed parts I need to fabricate out of metal but the progress was good for a couple weeks.


Still on the list is boring out the a-arm lug ends for the spherical bearings and grooving them for a snap ring.
 

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Discussion Starter · #148 ·
More two front progress. First the car:

I was able to bore out the holes for the spherical bearings at the end of the A-arms and also put in the grooves for the internal snap rings that will retain the sphericals. I'll get a couple more pictures once I clearcoat the arms since two of the ends I machined too undersized (not a big enough bore) for the press fit. I'll have to re-jig those two or figure something out. I didn't notice until I removed them from the jig because measuring the bore with a dial bore gauge requires decent access vertically. Live and learn


I created some spacers for the rod ends to the frame. Since the original a-arm setup from Factory Five has wide bushings and the rod ends are comparatively narrow, the gap had to be filled. Here's a simple, yet cool looking spacer I'll replicate for the locations.



Bridgeport resto progress:
Here's the knee components that lift and lower the table. Rather dirty and greasy.


The knee bearing that supports the weight of the table was just plain nasty. You can see the grease I picked out on the table below my hand. I then put it and the other parts in an ultrasonic bath. Thank goodness for cheap Harbor Freight jewelry cleaners and Simple Green :)


Components cleaned and ready to re-install. I was able to get the knee to raise and lower with the crank so that means progress!



Next up is finishing the spherical installs, clear coat the arms, make more spacers, and then finally install the arms to the chassis! And people talk about long waits on their suspension parts backorder list ;)
 

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Discussion Starter · #149 ·
More front suspension updates:

I got all of the a-arm spherical bearings and internal snap rings installed. The upper arms use a 'typical' spherical while the lowers that have more load through them and hold the weight of the front of the car up both use a wide ball spherical to take more axial load. Shown is an upper arm.


All 4 front arms with the spacers:


Rod end side to attach with the chassis. The washers are a set thickness which will later give me flexibility with alignment adjustments to dial in caster:


Lower arm with spacers on the chassis. Notice the gap that had me a bit confused at first:


Turns out the spacers were hitting the liner which was slightly thicker than the spec showed:


Instead of modifying the replaceable rod end, I narrowed the end of the spacer to clear the liner:


Upright progress is scheduled next
 

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Discussion Starter · #150 ·
I had a free night to work on the Coupe in the garage last night so I took advantage of that and started assembling all the components that I've been working to fabricate in little time increments available.

First up is the lower a-arm to upright bracket. I made the spacers to evenly hold the spherical bearing in the middle of the opening even though there's a bit of extra material on the arm itself. More on that later...


As a general rule of thumb for me, I didn't want to be threading into aluminum for a complex part in case the threads failed or got damaged. Didn't want to replace a complex part when I could more easily replace a simple part. This called for something to act like a nut that is captured in place. I've seen barrel nuts before so I replicated that. These are hardened steel rods that fit in the bores of the upright and are threaded. I matched the angle of the upright on one end to help with alignment since it's a blind setup.


Both a-arm brackets and upright all attached:


Some views of the tight clearances. Someone on Facebook commented on the caster angle but if you look closely you can see the lower arm connects in front of the wheel centerline and the upper arm connects just behind the wheel centerline giving me positive caster. The scrub radius is minimal even with the wide upper bracket because my wheel offset is +22 and that puts the pivot point just outside of center.



View looking inboard you can see the pushrod almost at the back of the upper a-arm. Once connected to the bellcrank it'll have a bit more clearance.


In the aft view looking forward, you can see the pushrod is really close to the CV boot. I thought it would clear more but obviously not, so I'll need to think about that one. I don't want it to rub and tear open throwing grease everywhere.


Finally, the front view looking aft. Here if you look at the a-arm brackets you'll be able to see a little bit of contact to the upper a-arm. I'll clearance that a bit and check where there's a rub with the upright at full droop and where full lock left and right will be. I have some rubbing and will need to disassemble it to see exactly where. Right now I have free movement up and down by a total of 4". I'd like to clearance that to get 2.5" up and 2.5" down with full steering lock at the extremes. Not that I'd be at full lock in full compression, but I'd rather it not bind on me either.


So, more to do, but more progress too.
 

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Discussion Starter · #156 ·
I got a little more time to work on the car over the weekend so here's the current state of it all:

I have a quick bracket for holding the steering rack in the expected location above the differential. It'll feed between the 'A' of the standard chassis above the upper a-arm as seen in the third picture. I made a wood holder for the differential to get it at the right height and already cut off the aft driver's side 'normal' steering rack bracket.


View looking top-down and forward. Everything is super tight to the frame. The differential needs to go further towards the driver's side to have equal length half shafts so I've already started notching the frame (after the pic was taken) to get it to fit correctly.


Side view of the steering rack and differential output locations:


Finally a wider view of the current front:


I need to finish the frame notching for the front diff, then cut out for the steering rack extensions, then I'll get the bellcrank and coilover mounts located. Lots to do but good to get a sense of front getting sorted out!
 

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Discussion Starter · #157 ·
April Fool's update:

I did some more checking on the width of the CV joints on the front differential and found I needed to shift the differential over another .2 inches to get the half shafts to be the same length. More cutting of the frame happened so I'll need to tidy it up from here. Sorry Factory Five.... it had to happen haha



It's ugly right now but I'll clean up the cut lines and then weld in plate to fully enclose the tubes again and keep water and debris from getting it and restore the strength.


I also bought some more filament to get some of the exhaust mocked up. Easy to do while I'm not able to get to the car since the printer just works away


I'll need to move the X-pipes forward a little but I'll finalize that once I have a real engine in and know the clearance to the harmonic balancer and accessories.


I also 3d printed a bracket mockup of where I'll mount the shock from the bellcrank (right side of image)



For the Bridgeport inching closer to assembled, I got the saddle (y-axis) cleaned, painted, and the oiling lines routed. Next I can put this 100lb part on the base and get on to the table (the 250-275lb behemoth)


The loose lines go to the ballscrews
 

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Discussion Starter · #158 ·
First, I'm still working on fitting the differential. I'm almost there for clearances but need to make sure I have room to weld the supports back. It's taken a lot more fitting than I first expected but I'm glad to finally have it sit in the right position. The pictures of that don't show visible change so I skipped posting them.

On another front... or side, in the case..., I played with the side exhaust exit and a cover for a standard style muffler. Some will hate the look and that's ok by me. I get that it's not the typical visible look, single or dual pipe configuration.

This is what nearly $20 in 3d printed PLA looks like


The design is to slip into the dual entry/exit Magnaflow muffler. It's a 'straight though' perforated design but actually is set up like a X so it'll act to help as a final balance between pipes and keep the exhaust flow going


I'll plan to clean up the looks with a side skirt that blends into the side of the body. Will still be distinct to the eye but flow better than a giant stainless steel oval with the letters MF on it.


Finally, this picture shows how far my wheels and tires go out running the stock Mustang GT rear axles (which I'll make new rear control arms for). I'll blend the side splitter into the wheel well body flares.


Now back to getting the front diff completely in place so I can move on to the rest of the drivetrain height, angle, and mounting
 
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