78 Big 10 on Wide Fives

[GoSki]

Looking through my photos I have discovered I only took two photos of the left side upper control arm shortening procedure. I must have been tired at this point, and grown weary of stopping to snap a picture. I elected to take 3° out of the upper ball joint plane and lay it more flat, this is because I knew the upper arm was going to be operating at an angle it was not designed to, and this gave my ball joint a little more breathing room.



Shortened next to stock length

[GoSki]

I brought the arms home and tossed the LF suspension on the truck.

At this point I still did not have a good feel for where the ride height was going to be, so I just took a rough guess and set things close. This mockup gave me a chance to see if everything was going to clear.

On the list of things to check were the upper and lower ball joint surrounds and the steering arm to the inside of the wheel. The clearance of the hub, rotor, and caliper to the spindle, wheel, and front crossmember, as well as how much the upper control arm would need to be notched for the steering shaft. And of course, tire clearance to the fender! I'll say that in the end, the tire clearance to the fender ends up being tighter than what these initial mockup pictures show, that is because the drop spindles I ended up using pushed the track width out from where the stock spindle puts it.

During this mockup session the front crossmember had not been sectioned yet, so not everything was sitting as it was going to end up, but it was still another data point to tell me I could keep going.

[Rickysnickers]

Wow, you really have quite a skill set!! Impressive work, I'm envious.

[SCOTI]

Nice fab work. The sectioned transitions for the arms are clean-clean.

[GoSki]

Originally Posted by Rickysnickers

Wow, you really have quite a skill set!! Impressive work, I'm envious.

Hey, Thanks!!

[GoSki]

Originally Posted by SCOTI

Nice fab work. The sectioned transitions for the arms are clean-clean.

Thanks SCOTI

[GoSki]

So the next step was to procure a set of drop spindles and marry them to some new Coleman wide five snouts.

I decided to use a set of 2.5" drop spindles from Mcgaughy's and a pair of wide five snouts from Coleman Racing Products.

I started by calculating how much I needed the snout to protrude out the front side of the drop spindle. This would dictate how far the hub slid onto the snout, and thus set the brake rotor location to line up with the brake caliper. After sorting that out, I put the snouts in the lathe and turned a very small amount off the OD of the press section up to the point I wanted them to stop for my plunge depth. This left me with a very small machine shoulder that I could use as my press stop.



Then I had to get creative with some fixturing, and make a few pieces in the lathe to secure the spindle into the mill. This boring process ended up being a two step process because of mill limitations. So I had to start machining the spindle bore from one side of the spindle, and then part way though I flipped and re-fixture and realign the bore centerline.











I machined a corresponding counterbore into the backside of the spindle and this gave the shoulder on the snout a place to land against.

[GoSki]

So now I want to mention something about the press fits and resulting interference forces that are generated from them. I'll avoid being a nerd and skip the excel sheet unless someone actually wants to see it.

When you press a round rod into a hole located in a chunk of material, each piece of material (the rod and the chunk with the hole in it) generates a force acting on the opposite piece of material. This is how a press fit works and stays in place. If you press a solid rod into a big thick chunk of material, both of those pieces have a lot of force to offer against the other piece. This is because the rod is solid, and therefore deflects very little, and the big chunk of material is thick with a lot of mass, so it has a lot of force to offer back against the rod. This is the scenario when you have a solid spindle pin pressed into a big cast spindle with a small-ish hole in it.

When you do what I am doing here, pressing a hollow rod into a chunk of material with less mass (because it now has a larger hole in it, and the material thickness around the hole is less than it was before) you are bound to decrease those interference forces.

The trick is to identify how much you are decreasing them by, and is what you are left with sufficient to do the job. Keep in mind, all of this is for the purposes for identifying if the snout is going to dislodge from spindle, whether that be via a lateral or rotational force. Being on the front end, the rotational dislodging risk is pretty low, as we are not driving the front axle with power, and unless a bearing were to seize, this is unlikely. The lateral dislodging is a more likely failure mode, but still unlikely if the math checks out for the press fit.

When I pressed the stock pins out of the 2.5" drop spindles, they came out with relative ease, the pressure gauge on the hydraulic hand pump registered around 4000 lbs, and the diameter of the ram on my shop press is 2.25", so it took about 16,000 lbf to press the old pins out.

When I calculated how much interference force I was losing by doing what I did, I came up with about a 40% loss.

When I pressed in the Coleman snouts, I registered just about 3000 lbs on the gauge, this equated to 12,000 lbf to press in the new pins. This was in fact only a 25% real world loss in force. This is likely due to the fact that I machined the bore and snout to have a bit more press fit interference than is normally standard for this diameter hole into cast iron (and what I based my calculations on) You have to be careful to not be too aggressive on your interferences for the hole size and material, as you can easily damage or break the pieces while pressing them together, cast material can be more susceptible to this.

I ended up with an interference of about .0015". Considering how much surface area is involved for this fit, that is approaching aggressive levels. To help "gain back" some of the loss of forces, I opted for a few more mitigating tactics.

1) I used Loctite retaining compound, which has a shear strength of 4,000 psi

2) I machined a weld on retaining ring for the outboard side of the snout, this was pressed on over the snout, and tack welded in place.
















One noteworthy thing with this retaining ring is that I waited a day before I tack welded it on, and that was to give the retaining compound a chance to dry. Also, I only tack welded it to keep from getting things hot and damaging the retaining compound.



Last thing worth saying, all of this was done rather than welding the snout into the spindle, because the spindle is cast iron, and those welds would be inferior. Had I been able to find cast steel spindles, I may have considered some welds as insurance.

[GoSki]

Then it was time to do another hub and rotor mockup to make sure I hadn't messed anything up.

[GoSki]

Once I had both spindle mods done, I turned my attention back to the control arms, I still had to do the right side and I still needed to modify the left upper to give clearance to the steering shaft.

I marked out where I thought I needed the clearance and drilled a hole with a hole saw, then filled it back in with a piece of tube. I have to admit that I had to do this twice, as once I got it home and all put back together I was not satisfied with the amount of clearance I had to the steering shaft, so I ended up doing it again.





















Here are two pictures of the upper arm after I redid the notch for a second time, this offered more room in the correct area, I was much happier with this. Although I think the first round looked better.





Here are the arms in the "all done" state. However, this is not true, later on the lowers ended up needing another small modification to clear the steering.

[GoSki]

The third big modification to the front suspension was to section the front crossmember. We did this on Corey's truck and it worked out well. This allows for more suspension drop without having to use big drop springs. We elected to take 1.5" from this crossmember, which is the same amount we took from the one on his 72 GMC.

We marked out the cut lines with a laser and then I cut it apart with a cut off wheel. Although this method is very noisy and dirty, it gives you a very clean and straight cut that can be refit and welded with ease.























I had to make two small filler pieces

[GoSki]

After sectioning a crossmember, you have to rework the horizontal mounting holes in the frame rail. You end up filling two of the old holes and re-drilling them in a new location on each frame rail.





After filling the holes and grinding them down, I used a DA to sand the frame rails before repainting, I have found this this to be the best way to "hide" your grinding marks.

[GoSki]

More Tomorrow.....

[SCOTI]

I saw 'dropped spindles' & immediately had concerns w/the TRE's interfering w/the back spacing on the 15" wheel.

Typically there can be interference which is one reason back spacing is limited when using smaller diameter wheels. Hopefully that's not your scenario.

[hewittca]

Originally Posted by SCOTI

I saw 'dropped spindles' & immediately had concerns w/the TRE's interfering w/the back spacing on the 15" wheel.

Typically there can be interference which is one reason back spacing is limited when using smaller diameter wheels. Hopefully that's not your scenario.

SCOTI, I'm with you there! I ran into that issue on my truck, so I was a nagging voice in the background of all this work reminding Nick that he may have tierod interference issues. I am from the future and can tell you it all works out.

Also Nick, we need to see that spreadsheet for proof you really are a nerd.

[SCOTI]

Originally Posted by hewittca

SCOTI, I'm with you there! I ran into that issue on my truck, so I was a nagging voice in the background of all this work reminding Nick that he may have tierod interference issues. I am from the future and can tell you it all works out.

Also Nick, we need to see that spreadsheet for proof you really are a nerd.

My assumption was it did work out since the truck made it out to an event. I just wondered/thought.... If there was some extra effort required, I hope it wasn't too drastic.

For others following this work, I did my first crossmember sectioning pretty similar to how GoSki did (including making the filler pieces).

On the subsequent ones I've done, I use a big freakin' crescent wrench to tweak the upper & lower areas that are mis-aligned once the material is removed from the center.

I reference mark the areas w/a Sharpie to know where the gaps are. I move the lower in a bit while pulling the upper out in those areas. A couple of rounds tweaking things lines them up close enough that the weld bead can get it done. Just an alternative....

[GoSki]

Originally Posted by SCOTI

My assumption was it did work out since the truck made it out to an event. I just wondered/thought.... If there was some extra effort required, I hope it wasn't too drastic.

For others following this work, I did my first crossmember sectioning pretty similar to how GoSki did (including making the filler pieces).

On the subsequent ones I've done, I use a big freakin' crescent wrench to tweak the upper & lower areas that are mis-aligned once the material is removed from the center.

I reference mark the areas w/a Sharpie to know where the gaps are. I move the lower in a bit while pulling the upper out in those areas. A couple of rounds tweaking things lines them up close enough that the weld bead can get it done. Just an alternative....

SCOTI,

As Corey mentioned, it did work out, however, when I go to check my bump steer, and if find that I need to flip the outer tie rod, it is not going to clear the tire sidewall unless I change to a heim joint instead of a ball joint.

Thanks for the input on the crossmember sectioning.

[GoSki]

Originally Posted by hewittca

SCOTI, I'm with you there! I ran into that issue on my truck, so I was a nagging voice in the background of all this work reminding Nick that he may have tierod interference issues. I am from the future and can tell you it all works out.

Also Nick, we need to see that spreadsheet for proof you really are a nerd.

Alright Corey, here it is, however, it's minor league nerd, because you have no fun equations visible.

The 3rd column titled "w/slugged Coleman Pin" is an option I did not do, but still could. This math correlates to if I were to machine a 50.7mm diameter by 50mm long cylinder and press it into the hollow Coleman Snout. This would restore more of the interference force to the equation because it effectively prevents the pin from deflecting radially and the force that causes that can instead push back against the spindle.

[GoSki]

It was time to bolt up the front suspension and set the truck on the ground. The was also the time to install the steering components and see what (if any) clearance issues we had.















You'll see here that the center link was making contact with the front leg of the control arms, this was on both sides.





So, more control arm surgery was in order.













This shot shows how much the "hump" was lowered compared to the other leg behind it.

[GoSki]

At this point in the build it was mid summer of this year. Corey and I have made a tradition out of going to the C10 Fall Revival in October every year, and I had it in my mind that I wanted to go to the show in an old Chevy. I knew this truck would not be done in time, so I pitched the idea to Corey of buying a old running beater and spending a couple months just doing small things to it so we could have something to take to the show.

After some thought Corey suggested what if we just get my current truck looking like it was complete from the outside and trailer it to the show. I thought this was a good idea, but it was going to be a lot of work to make it happen. At this point we had 10 or 11 weeks to get the truck ready. So we locked in on that as our goal, and I had to get ready to spend some money.

[GoSki]

Making the truck look complete meant a lot of work to body panels, painting, patina, rebuilding the doors, installing new front and rear glass, trim, and narrowing the rear axle. There was a lot of work to do, and a lot of parts to buy.

In order to pull this off, it was going to require a lot of help from Corey, we were going to have to work on things in parallel, so I ended up feeding him body panels a few at a time that he could take to his house and prep so that we could shoot paint.

I started with the doors. The driver side was in much better shape than the passenger side. I knew I wanted to save as many body panels as I could because they had the right patina that matched the hood and roof. I ended up replacing the bottom half of the passenger side door because it was totally gone.





While I had the doors apart for repair and paint, I took the opportunity to rebuild all the door mechanisms and vent windows.













I was able to fix the broken stud on the bottom of the vent window. I welded a new stud to the bottom of it and then filed that two flats back into it, then just chased the threads with a die and it was good to go.

[GoSki]

While I had the doors apart I also machined some new door hinge bushings to tighten everything back up

[GoSki]

The core support was pretty crusty looking, but in good enough shape to be saved and reused, just went with the old fashioned wire wheel, hand sandpaper, DA, and scotch brite pads. Then paint.

[GoSki]

One thing I had been stuck on for months (maybe even a full year) was if I was going to reuse the bedsides or if I was going to buy different, or new ones.

For a year and a half I was always looking on Marketplace for a full short bed, or a full long bed that had patina but no rot, I was willing to cut down a long bed if I had to, and of course a short bed would have been best, but I never found anything that was good enough and close enough to me to make it worth the drive.

The reason for all of this is because I just couldn't get past the very strange circular rust pitting that was all over my bed. The driver side was almost completely rust, and it did not make for a good look, especially knowing I was changing the color of the truck. As I already mentioned I started to shorten the passenger side, but stopped to focus on other parts of the truck.

So after storing these old bedsides for almost 2 years, I decided to just go buy new ones. I am fortunate enough to live 12 miles from a National Parts Depot, and this really came in handy for the last few months of this build. Not paying freight, and not waiting on the infamous LMC Truck shipping was a luxury.

For any of you trying to keep track of what I kept for original body parts, here is the list for you.

Original Sheet metal

-Cab
-Hood
-Lower Valance
-LS Fender
-LS Door
-RS Door
-Bed Header Panel

Marketplace Sheet Metal

-RS Fender
-Tailgate

New Reproduction Parts

-Bed Floor
-Right Bedside
-Left Bedside
-Wheel Tubs

[GoSki]

The RS fender was too rotten to use, so I found one local to me on Marketplace, it came off a 77 Custom Deluxe.