Brake development

So one of the criticisms of the 818 kit is that the braking solution is... not inadequate, exactly, but wanting of some improvement. I have to give a lot of credit to my uncle, Ed Holyoke, who researched and developed the braking solution we're both going to be using on our kits. That's also his photo there to the left, which I am using with his permission.

This is the setup for the rear brakes we're looking at, on his custom bracketry. There's a massive Brembo/Cadillac caliper at the right to act as the service brake, and a little cable-actuated Wilwood unit at left for the parking/emergency brake. Both of those will squeeze a truly massive caliper, sourced from the front axle of a Subaru WRX STI.

The fronts will also get the same Caddy caliper and the same STI rotor, but there's an existing bracket solution for that upgrade. Roughly speaking, we're doubling the braking effectiveness in the front, and quadrupling it in the back.

There are a few reasons this is important:

First, the kit uses unboosted brakes. There's no vacuum assist here - all the braking is powered by the driver's leg. Second, while the donor's engine is in the front, the kit will have it in the rear; this affects the weight balance of the car significantly. While nearly all cars have much more braking at the front to deal with the additional mass at the front of the car, the kit needs help around back. Third, these kits may very well see some track use, so more braking will be better for that, including extra mass for dealing with heat.

Long story short, the idea of the kit car is to make something that will accelerate and handle at very high levels - so stopping is also going to be important. As far as bang for the buck, this solution, while not exactly cheap, is a great bargain.

Marking tools - in use!

 Lot of pics here to show how I used the three marking tools I made to locate two holes.

That's the hole I needed to mark from the center of, so the conical end of this tool allows me to locate on that.

 The other end has a hole sized to take a Sharpie.

 So when it's all assembled, the tip of the marker is two inches from the center of the cone.

 Using that, I drew an arc on the control arm.

 This is effectively an edge marking tool - I needed to draw a line 1.5" from the front edge of the control arm. The step on this tool rides along that edge.

 And of course the other end accepts a Sharpie to draw the line.

 Next, from the intersection of those two lines, I needed to draw a line at right angles to the axis of the mounting bolts. I didn't print the square; I already had that lying around.

 Once the first hole was punched and drilled at the intersection of all three lines, the third tool came into play. It locates on the drilled hole with one of the bolts I will use in mounting a bracket here.

And again, using a Sharpie, I drew an arc, crossing the line I made with the square. Then I punched and drilled a hole there.

The bracket isn't painted yet (maybe tomorrow), but here's where it will go. The bolts lined up quite nicely with their holes, so it will all go together quite well.

Marking tools

I love it when my hobbies interact to facilitate each other. I have some parts ready for paint - may get the paint going this afternoon - but once they are painted, I have to drill some holes on donor parts to mount them.

The directions for doing so are kind of rubbish. For example, they say to measure 2" from the center of an existing hole - and the picture shows a builder holding a measuring tape approximately in the center of the hole. Preferring some degree of precision and repeatability, I designed and am now 3D printing a marking gauge (the one in purple) that will let me mark that 2" more easily. The other two gauges will allow other, related markings. I'll post pictures of them in use once I get them printed and, you know, in use.

Forward firewall is complete!

 Not a complete ton of progress today, but I did get the final panel of the forward firewall installed. At left, it's all drilled and Clecoed. Below right is an overview of the finished expanse of the nose area of the car. Later on, this space will get filled up with suspension bits, the battery, the radiator, and so on.

The next steps in the book all relate to the front suspension. The kit reuses the front lower control arms from the donor, with an additional bracket added. And of course the bracket is one of the parts that is backordered for by kit. Full thanks to my uncle, who also had these parts backordered, and who reached out to Factory Five to get the parts sent to both of us.

I have a few parts in the front suspension, including those backordered brackets, which are unfinished steel. I've been working on wire-wheeling the ones I have in prep for paint. As they come from F5, they still have what appears to be welding flux on them, plus scorch marks from laser cutting, and so on. Here are some suspension uprights, which will connect the donor steering knuckle to the kit's upper A-arm. The top one is as delivered; the bottom one has been wire-brushed.

The rivets are coming from inside the car!

 The first thing I did today was to get the frame down off the jack stands and onto some wheeled dollies. This will let me move the chassis around, so I can make room to get to one side or the other as needed, and push it out of the way when I am not working on it. It's a lot closer to the eventual finished height on these dollies.

 Not quite there, but I believe the goal for the finished ride height is four to four and a half inches. As my wife pointed out today, this means I am going to have to be very careful around speed bumps, to avoid getting high-centered.

Here's the panel I worked on today. It's in progress here, but I did finish it. I am actually sitting in the car to take this picture, on the passenger side. Not in a seat, unfortunately, but on an upturned milk crate.

The panel rivets in on the inside of the frame here. Got it all marked, drilled, Clecoed, deburred, cleaned, and riveted up. I got a late start because of stuff, but it feels good to get work done on it and to keep the build moving forward and not stalled. I have one more panel for the forward firewall.

After that, the build manual says to work of the front suspension - but there are still some critical parts backordered for that portion of the build. I'll have to decide what to do next.

Pushing more tin

 Had another very satisfying day in the shop today. When I had left off on Sunday, I had 3 out of four pieces of the driver's side firewall ready to rivet in. Today I got the fourth piece all set up, and riveted up the entire driver's side assembly.

The new pneumatic rivet puller makes this so much easier than the manual riveter I was using before. It's almost not fair.

 The passenger side is next. This triangular piece felt like easy mode after all the hooraw with the driver's side. Here's the first fitup, where I just clamp it to the frame and mark where it fits against the tubes.

 Here it is with those markings. I had to do a little more to find places that I would not be able to get at with the drill or the riveter, but no big deal.

Mark, drill, deburr, drill frame, Cleco, deburr, clean, add sealant, Cleco, rivet. At right, the frame is drilled and the panel is Clecoed up.

And here's where I wrapped up for the day. Couple more panels to do on the passenger side, and then I believe it is front suspension next.

3D printed edge marking gauge

 Works with Extra-fine and Ultra-fine Sharpies.

Makes a line 1/4" from the edge of your sheet metal, wood, etc. Printing a 1/2" version now, and obviously these could be made in any required size.

Pushing Tin

 I had a very satisfying day on the kit today. Not only did I get the pedal box bracket finally mounted, but I also managed to make a lot of progress on getting sheet metal installed for the forward firewall.

The forward firewall is seven pieces of aluminum, all in shapes and sizes, that go together to form the barrier between the cabin and the area where the radiator lives. The build manual makes it sound like you are starting out easy, just doing the left half, but several of the pieces overlap, and they all depend on each other for positioning and fixing, so it turns into installing them all before you can install any of them.

At left is a picture of the entire firewall mocked up and just held in with clamps, but I actually did get three  pieces of the driver's side ready for mounting, and about halfway through the fourth.

 This bit is the inboard strip of the driver's side - you can see some holes in it that have to line up with matching holes in the pedal box bracket.

It's not really visible here, but every hole has to be thought through pretty carefully - not only do the pieces mesh with each other, but it's also important to consider tool clearance in planning - can I get a drill in that spot? Can I get a rivet tool in that spot?

For example, where this panel sits next to the pedal box bracket, I wanted to put a couple of rivets about 1/4" from the edge - but my rivet tool needs 1/2" of space to fit in there - and moving them would make the rivets fall outside of the tube I wanted to connect to. Overall, I ended up skipping a half-dozen holes or so. Would have been more except for a low-profile right angle drill I have.

And this is the piece that started the series of Catch-22s. it gets overlapped on both sides, so it's important to relate all the pieces to each other before drilling any holes.

But it's all coming together very well. Tomorrow or Tuesday, I should be able to pull rivets on the driver's side firewall.

The passenger side is a lot simpler.

Pedal Box Mount Bracket

 Last night after work, I got the last coat of paint on the pedal box mount bracket. It's still not what I would call a good paint job, but I'm going to call it done.

 The basic problem, in addition to my being rubbish with a spraycan, is that it's a weird complex shape, with overhangs and inside corners and tight spots all over it. I'm at the point now where I probably could make it better, but it would require several times the effort - so it's good enough for now.

 Here's where it mounts to the forward firewall. All the pedals and hydraulics mount up here, so this is a pretty strong piece of steel. It's going to spend its life being pushed on, hard, by my feet.

And there we go, all mounted up. It looks not half bad once it's in place. Next, I have to assemble the forward firewall out of several shaped pieces of aluminum. And guess what that means? More pictures of Clecos, coming soon!

Painting parts

Man, am I rubbish with a spraycan. I guess I am impatient and inconsistent. I had some issues the first time I tried to paint this part, so I had to sand off some problem areas, and now I am going after it again. I think it's going better this time.

It's going to be way under the dash, and no one will ever see it once the car is built, but I just want it to look reasonably good.

I've also been really frustrated with my work schedule. On days I work, I only get a little bit of time each day to work on the car. I do get three day weekends every week, but I just want to get more done.

But rushing is the enemy.

How to rivet on a panel, part 3

Boy, work weeks are terrible for shop productivity. I had hoped to at least get a few minutes in the shop during my work week, but I just couldn't.

Anyway, in Part 2, I was frustrated with rivet spacing, so I went into a side trip of designing and building a "rivet fan," a tool for spacing rivets. It was a little funny to have the 3D printer running here in my home office while I was working, but it all came together just fine, and I'm glad to report it works great!

 Here it is, in fact, in its natural habitat. It expands pretty far, so I am able to mark ten locations at 3" spacing, or anything down to about 3/8". This makes it easy to fit a series of holes to a space.

 So once I have all the locations chosen and marked out, I used a hammer and a punch to make a dimple at each mark, so the drill bit would not wander.

 And then I drilled the holes.

 And then deburred them, from both sides. If they weren't deburred, the panel might not sit tight against the frame.

 And all the cut edges of the panels also got deburred with a file - again, from both sides.

 All the markeings got wiped off with acetone.

 And then the panel got clamped back onto the frame. I used the blue tape and Sharpie marks to get it back where it had been.

 Then, I used the holes in the panel as guides to drill holes in the frame. I put a Cleco in the first hole, and about every other hole after that, to keep the panel from shifting relative to the frame.

 And here it is with all the Clecoes in place.

 Once I had the frame all drilled, I took out all the Clecoes and removed the panel, and went back to deburr all the holes in the frame.

 And I used a caulking gun to apply sealant to the panel all around the edges and along all the lines of rivets.

Then I put it back on the frame and started pulling rivets.

It's all riveted up now, and it looks really good. Tomorrow, after the sealant has had a chance to cure, I will clean off all the bits that squished out, and I will wipe down the outside of the panel to remove all the ink and such.

Also tomorrow, I hope to clean up and paint a bracket and possibly start on the front firewall.

Rivet spacing tool, v.1.0

Here's the final (for now) version of the rivet spacing tool I have been working on. This one is smaller than the first try, which makes it less floppy. I only need a maximum of 3" spacing, which this provides nicely. And, for the aesthetics of the thing, I modified a couple of the legs to remove an unneeded sticky-outy bit and an excess hole.

Now I can get back to marking and mounting the next panel.

Rivet spacing tool, v.0.5

Here's my first attempt at a 3D printed rivet spacing tool. It has a couple of issues, so I am printing a refined version now.

Delivery day retrospective

I've been meaning to post this for a few days - here's my wife's post, over on her blog, about the delivery of the kit. It was very cool. She takes much better pictures than I do, and she had more time to take them.

How to rivet on a panel, part 2

At the end of part 1, I was a little frustrated with getting the rivets to come out nice. My uncle mentioned a "rivet fan" as a tool for spacing rivets. But I can't get one reasonably priced and quickly.

So I woke up early with the realization that I could make my own. A quick trip to the hardware store, a little tinkering in CAD, load some filament in the 3D printer, and I am on my way to a homebuilt rivet fan!

How to rivet on a panel, part 1

 Apparently, I have become neighborhood famous; in the couple of hours I was out in the shop today, I gave two nickel tours of the frame and the assembly process.

But today, I wanted to detail the process I am using to attach an aluminum panel to the frame.

First, the panel is held against the frame with clamps. I do a lot of eyeballing and measuring and feeling until I feel like it's appropriately lined up, and I use blue tape and Sharpie marks to make some references.

 Then, from the other side, I make lines outlining all of the tubes it will rest against.

 On the bench, I do a lot of layout with rulers and Sharpies to figure out the lines I will put rivets along, to hold the panel firmly to the tubes.

 Here's a closer view of my layout lines.

This is a marking tool I made from a cheap aluminum framing square. Once side has holes on 2" centers; the other side is 3" centers. I'll use this to mark out the rivet spacing. In this case, because the panel is being mounted to the frame, I'm using 3" spacing.

I did not get the whole panel marked for rivet locations today - I'll finish it up tomorrow, I hope. I think it needs a little revision anyway, so that things come out a little nicer than they currently are.