Now that the fabrication work is done on the setup pads, it’s time to set up the setup pads so that the setup pads can be use to set up the car.
First thing’s first: Paint. It’s always paint.
Step 2 is…more paint, oddly enough. I picked a fairly central location in the shop for the setup pads, then got them on the car so that they could be squared up, so that their locations can be marked. This is so that each pad goes in the same spot, in the same orientation each time, that way once they’re leveled, they remain consistent.
I made up a stencil to use for marking the floor, put the foot of each corner on the circle in the middle, then marked out the perimeter with tape.
That done, the stands came out from under the car, the car was moved out of the shop, and each spot was marked:
Next it was time to level the full set. I started off by setting the feet to their highest setting so that I could find the lowest corner, and then adjust the rest of the pads to meet that corner.
CUE THE LASERS!!!
I used a couple of my big fabrication squares, made white backgrounds (to better see the laser) and then made a mark on each at the same level. Get the lines on the squares to meet the laser at both the front and rear of each pad, and you’ve got it level.
With the setup of the setup pads done, it was time to…. do some setup on the scales. Specifically, I was sick of dealing with the rats nest each time I unspooled the cables, so I made left- and right-side “harnesses” to keep things tidy. They’ll run under the car down the middle so that they’re out of the way of jacks and what not.
And with that, somehow, miraculously, despite taking what felt like most of my life, they’re complete and in service! They look great and will work great. Having now used them exactly once, they were already worth the effort. Being able to get and keep a consistent setup on the car (and help friends with their cars) can only be a good thing.
Roll off pads are very useful for setup, allowing a place to make alignment changes, to zero the scales, and to allow the tire to roll to undo any bind that setting changes may have introduced. They are also the thing that adds a TON of cost to the commercial setup stand options.
Since I’m fully committed at this point, might as well go big.
The pad itself will be a pieces of 1/8″ aluminum sheet, supported on both sides and in the middle.
The side supports are made of 3/16″ steel bar with 3 holes per side drilled and a nut welded to the back side on each to secure the plate. The bars are supported on 3 sides, sitting on the frame on the short sides and 1 long side. Those bars on top of the frame puts the floor just a shade lower than the scale pads, allowing space for some thin grease plates to do alignments.
The center support is a length of 1″ bar with 3 holes through it. 1/4″ on one side for the bolts, and just about 1″ on the bottom to allow a 10mm socket with an M6 nut to be inserted from the bottom.
Once the 2 sides were done, the next challenge was fitting up the middle support tube such that it was dead level with the 2 sides so the floor is perfectly flat. To do that, I flipped the entire frame so that the side-supports were flat against the welding table, then placed the tube in to get tacked up so that the welding table top became the reference surface for the whole setup.
With the frames completed, it was time to fab up the floor. After rough-cutting it, clamped it to the frame and drilled the 3 central holes as they can be accessed from underneath. The challenge, however, was to get the position of the 6 holes on the sides that were covered up by the angle iron.
This is where a DILYSI Dave hot tip came in incredibly handy. Long ago when I was building the new Seat Mounts, he suggested making some blind transfer punches out of some bolts. I made up a few more so I’d have a full set for this job. I threaded them into the holes, then bolted down the 3 central bolts so that the floor would be in the correct place, then gave each location a sharp whack with a rubber mallet to mark its location on the aluminum sheet for drilling.
With the prototype nearly complete, I wanted to do some strength testing (ie: dropping the car on it vigorously a few times) to make sure there weren’t any glaring issues:
And since I was painting the new Saw Stand, I figured I might as well hit this one with a coat of paint. This, it would turn out, would be a mistake.
The keen eyed will notice 2 glaring omissions at this point (the point at which I thought I was done with this…). 1. There is no provision for the cable for the scales to pass through, and 2. There are no wheel stops. The commercial ones don’t usually have wheel stops, but they’re much shorter so were you to roll the car off of them, the likelyhood of them damaging the car is fairly low. These are very tall, and VERY strong. As such, should the car roll off of these, it would be ugly. I’ll address these next.
First up is a notch for the cable. Attempt number 1 was…. well… fugly. I tried doing it with and angle grinder and the results were bad.
It was at this point that the true value of a welder came into play. That was ugly enough that I decided to un-cut steel.
After a rethink and some consultation, I decided to use a hole saw instead. Normally this wouldn’t be a problem, however at this point, with the frame fully assembled, it was a bit late in the game. This is by far the dumbest thing I’ve ever chucked up in the drill press, but damn if it didn’t work!
(I’ve no idea why this photo shows up sidewards. Click the picture for the right-side-up image)
Thankfully the results were most excellent. After a little cleanup of the sharp edges and corners with a flap disk, I was very happy.
Now that I know where the notch needs to go, subsequent cuts were FAR easier.
On to the tire stops. After a bit of figuring and evolutionary engineering, I ended up with an easy to fabricate, dead simple solution that will 1) stop the car rolling off the ends, and 2) still allow the stands to stack together to minimize the space they take in the shop.
Part the first is a 2″ length of 1/2″ OD tube welded in the center of each end of the frame:
Next is a 6″ length of 3/8″ steel rod, with a bend around the 2″ mark and a bullet nose ground in on each end. The bend is so that they won’t just fall through the tube, and it leaves a ~4″ step that would take an immense amount of force to get the tires over. If you figure out a way to do that, you do your alignments far more aggressively than I.
The short side / long side has an added advantage that I wish I could take credit for but in reality was a complete, but happy, accident. Up front, that long post interferes with the splitter when rolling the car back and forth between the scale and the roll off pad.
With it flipped upside down, there’s still plenty of a step to stop the car (plus the taller sides are still up at the rear), and the splitter clears easily. I love it when a plan, accidental or otherwise, comes together!
Many moons ago, a buddy posted a few pictures to Facebook of his car on some setup / alignment pads. My curiosity piqued, I reached out and got a bit more info from him, as something similar would be phenomenally useful. I’d looked at commercial options for these, but they are prohibitively expensive, and John’s homebuilt pads looked pretty close to what I wanted for a lot less money.
After a great deal of figuring and bouncing ideas off of engineer friends, it became clear that a set could be made that would also incorporate setup scales, for relatively little cash (and a great deal of time….so, so much time). Initial designs were drawn up and steel ordered.
What follows is going to be a boatload of photos of various stages of the build. It was a very very long process of evolutionary engineering and problem solving, but now that I know how to build them, additional sets will be made relatively (and it is very relative, because they’re a ton of work) easily.
First step: getting a bunch of steel home. I had various pieces cut more or less to length, as I didn’t know exactly how they would go together but had a general feel for at least what the long legs needed to be. The rest were cut to fit in the back of the truckster to get it home.
Lots of measuring (way more than twice), cutting, coping and beveling later, and the first frame was roughed out.
The scales will sit on the side with “floor” on all 4 edges, and the rolloff pads will go opposite them.
Cutting 45 degree miter joints would have been far easier from a fab standpoint. However coping the joints has 2 very big advantages: it leaves nice, flat areas on each end of the “long” side of the frame for the legs to sit on, and with that, there is a lot less strain on the welds and puts everything in compression, with the welds mostly holding the pieces together, and not supporting the weight of the car.
It’s not that I don’t trust my welds, but with something that needs to hold the weight of a car from crushing me to death, I will take every bit of added strength I can get.
A quick test fit was very encouraging. My measuring a dozen times lead to a fit that allows the scale pads to rock in and out easily, but not enough that they can move around too much.
Mocking up the legs:
Got the rest of the gussets and the horizontal supports done.
A design requirement was to have feet at each corner that will allow the full set to be leveled. The first step of that are these that make the bottom of the legs, with the threaded nut inside the leg. So, weld the nut to the washer, then weld that assembly to the leg.
The rest of the parts stackup.
This once again goes into the strength of the thing. Once the jam nut is tightened up, all of the load is on the big washers at the bottom of the legs and the bolt, and virtually none of the operating load is on the tack welds securing the nut on the inside of the legs.
With the basic design roughed out, we’ll work on the roll off pads in Part 2.
I’ve coveted them for a while because the stock rear adjusters tie toe to camber, and these allow you to do 2 really interesting things:
Adjust toe and camber individually.
Play with suspension geometry a little bit. Because the upper rear arm is nearly infinitely adjustable, you can use the stock alignment cams to set toe, but also set track width, and then compensate by making the upper arm longer or shorter to maintain your alignment.
Easy, consistent adjustments. Each 180° turn on the control arm translates to a 1/4° change in camber.
It’s one of those things that gives you plenty of rope to hang yourself with, but if you take your time and plan out what you’re doing (and take lots of measurements), you can do a lot of good as well. Which means I’m probably going to end up metaphorically hanging from the end of that rope…
There were some concerns about the strength of the threaded components, so I took a few measurements. The gist of it is: the shaft is 3/4″ diameter, and it is a fully threaded sleeve on the control arm portion so there’s thread engagement far beyond the front and rear “nuts” it looks like it has. Barring some weird metallurgy issue, these should be plenty strong.
Finally installed with the car. Between the adjustable upper arm, the adjustable offset upper-outer bushing (in the knuckle) and the stock cam adjusters, there’s a lot of adjustment now built into the suspension to make (or break) the setup.
On to the tires: There is a readily available Formula Atlantic (I think?) Avon A11 compound Radial Slick in a 240/600R15 size. It’s about 1/2″ taller and wider than the Hoosiers I’ve been running. I’m not thrilled about the taller bit, as it may end up with some interference with the chassis, but the wider should be nice. And they allegedly last longer than the Hoosiers, while being as easy to get.
Ideally, I’d be on a 275/35/15 Hoosier A7 or a 21.5 x 10.7 x 15 Avon, but those are friggin expensive, and unobtanium on the used market, so I’m going to see how these do, then end up settling on either these, or the 23 x 9.5 x 15 Hoosiers after this set.
And finally, last night I had a buddy come by to help drink my beer and measure while I adjusted from under the car. While the last set of tires wore fairly evenly, it was apparent that the rears needed a little bit more camber, and the fronts needed to be adjusted. I think they got knocked out of alignment over a couple big bump at an event, because we found about -1.5° degrees camber on the left side and -3.5° on the right. Definitely not ideal.
After roughing in the rears to be even, I threw the “Me Simulator” 210 lbs of steel plates into the driver’s seat and we got to work. The alignment numbers I ended up on are:
Front Camber: -2.75°
Front Toe: 5mm out
Front Caster: as much as I can get away with and hit my camber number…
Rear camber: -1.75°
Rear toe: 0″
We’ve got an event this weekend so we’ll see how she runs, and go from there.