Sunday, April 21, 2019

Handbrake Assembly | Roundtail Restoration

Hi everyone! After a bit of vacation, it's time to get back to working on Dorothy. I actually did the work below before I left, so now I'm caught up. Here's the video:


Since I had the new rubber grommet, which is integral to the handbrake operating properly, I wanted to see how it all comes together. It's surprisingly complicated (to me, anyway). But, I had all of the required parts (well, mostly) and the workshop manual, so I was ready to go.

As a little refresher, here's the drawing from the workshop manual. If you see a number(s) following a part name, it refers to this drawing.



The handbrake lever (4).

I was missing one of the small clevis pins (23, 25, 41) so I took a long one that I had laying around and made it fit my needs.

Getting ready to drill a new hole for the cotter pin.
 
Original (L) and modified.

Original (L) and modified.

That sorted, I moved on to routing the cable and getting it fitted properly. The relay lever (9) is supposed to sit, with the handbrake released, at a 15-degree angle.

How its supposed to sit. The picture is flipped and inverted for some reason, but it works.

I used my cam timing wheel to make a 15-degree triangle out of cardstock so that it was easier to see what I needed to do.

Template made.

Then I attached the relay lever (9) and the compensating sector (24) to the mounting bracket in the body and used the template to properly align it. That done, I taped it down to prevent movement.

Angle set. 

With the angle set, the cable length is adjusted, using the clevis (40) and the large threaded portion of the front of the primary cable (37). In my case, I had to shorten the effective cable length.

Where the adjustment happens.


What is looks like from underneath. 

I'm sure you can do this in the opposite order from how I did it...adjust the cable length, moving the relay lever until it sits at the right angle. I just figured it would be a bit easier with the cable not attached to the relay lever.

With the cable length set to get the proper angle, the next step is to put the cable under tension. This is done by compressing the spring (35) "about an inch" and then locking it down with the clamp bolt assembly (30-34). I'm not real crazy about how tightly this grabs, so I may have to revisit it. 


Cable tensioned up.

In this condition, even though it's not connected to the rear brakes, it is possible to test the handbrake, which I did in the video. Pretty cool.

After that I moved on to fixing the crack that I put in the bonnet when I was trying to set my gaps. As I suspected, this was a crack that I previously "repaired" so it was already weak. I welded it better this time, I promise!

Crack, pre-repair.

And post repair.

And that was about it. This was only a weeknight visit so not a whole lot of time to do stuff, but progress all the same. Cheers!



Wednesday, April 10, 2019

Odds & Ends | Roundtail Restoration

Lots of random stuff this time. To the video:



With all of the gaps where I wanted them, I needed to mark each of the hinges and various other points for reference. That way, when it's time for final assembly, I hope to minimize the pain...we'll see how that works for me!

I picked up a nice Starrett punch from Amazon for this. A bit pricey, but I knew it being a Starrett, it would be very high quality. I don't have any pictures (they're in the video), but I also made several metal shims out of 16-ga sheet metal for the door hinges. This will save me from using a lot of paper shims.


Little punch dots on the hinge.


More punch dots, more clearly showing (kinda) the matching dots on the A post as well.

It was also important to mark which hinge was which, top or bottom, for the door as well. I punched in the letter "T" or "B" for the top or bottom hinge, and segregated the driver's and passenger's side attachment hardware into their own ziplock bags.

Hinge marked, ready to be bagged up.

I followed the same general method for marking the striker plates on the B posts and also the pivot hinges for the bonnet. Hopefully it'll work out and make putting it back together a bit easier.

That took most of the visit so, at the end I was looking for some low-hanging fruit and decided to polish up the boot hinges with a 6" buffing wheel I picked up from Harbor Freight for my bench grinder. They're old and there's some pitting in the chrome, but all in all not too bad. Definitely re-usable. I'll do more work on these, with some chrome polishing compound, and I expect them to get better.

Polished (L) and not. The polished one looks better in person.

The polished one.

And unpolished.

First up for the next visit was to get the body back off in preparation for final body work and paint. I've documented this before and used the same method with no issues.

Another area to focus on before the body gets landed for the final time is the handbrake. A lot of its linkage is under the car and very difficult to access and adjust with the body on the chassis. I have new cables and some hardware, but will be re-using all of the old brackets and such - they needed to be cleaned up in preparation for epoxy.

Cleaning it all up is easy, of course, but the arrangement is a bit tricky. I didn't pay too much attention when I was taking it all apart on either car (and both were in various states of disrepair) so I'm not positive how it all should look. I've got the workshop manual, though, so that's should hopefully do it for me.

Workshop manual.


The black car's primary cable (37, cut) with the clamp bolt (30-34) and relay lever (9).

Another portion of the assembly that is nearly impossible to fit with the body on the chassis is the rubber primary cable grommet for where the cable comes into the passenger compartment. From my research, later cars (the Mk3 and onward, I think) used a tube in this area vice a grommet, which I assume was used for being better at keeping water out.

These grommets are unavailable, but I asked on my favorite forum about them. I was lucky enough to have a gentleman from my favorite forum offer to make some with his super-awesome 3D printer. I took some measurements and...voila! A new rubber grommet that fit perfectly. Gotta love modern technology!

Grommet from inside the car. This has a split collar for easier installation, but other versions did not.

View from under the car.

Along with all of that I also cleaned up one of the headlight dip switches. These are like the old American cars where the bright lights were actuated with your left foot. Triumph, on the USA versions of the Spitfire, used the same setup. This one came out of the black car and was painted black and covered with the undercoating that was all over that car. Pretty yucky, but it cleaned up just fine.

Much better.

The next item to repair was the rear license plate lamp. Dorothy's was rusted away to about nothing. The black car's wasn't much better, but I was able to pick one up that was not too bad. The inner bracket, however, wasn't that hot. I decided that the bracket had to come out for repair and painting. First, I removed the paint from the outer piece to expose the spot welds to drill them out.

"Outer piece". The light itself attaches to this part.

The inner bracket, all bent and rusted. That nut is rusted to it as well, but I think it's a captive nut.

Inner bracket removed.

Inner bracket, other side.

The outer bracket after drilling out the spot welds.

Since the captive nut had been drilled out at some point and was beyond repair, that needed to get ground off. Also, I needed to fix the corners of the bracket. To make both of these easier, I pounded the bracket flat.

Bracket flattened out.

As I sometimes do, I decided during the repair that replacement was the better way to go. It was only 20-gauge metal and just a rectangle with some holes cut in it - easy to fabricate, so that's what I did.

New piece made, with marks on where it needs to be bent.

Bracket bent and trimmed at the edges to fit back into the outer bracket.

I got the bracket bent and fitted, but I held off on welding it back in. The new bracket is quite square so it'll need to go in a bit crooked to make sure the outer bracket is square to the body. I also need to paint it an all of that, so it'll be finished at a future date.

And there it is. Not perfect, but it'll do.

That was about it. Like I said, lots of odds and ends. Cheers!