Today was a day of focaccia fueled shop work; mostly fitting little drum brake parts and focusing on some of the kart's little holes. One drill bit required a soldered extension.

This morning I gathered up enough mental focus to install the liners in the brake drums. After boring for an interference fit, I heated the drums to 600* F and dropped in the rings.

Very nicely done Chuck. But......you didn't think you would get away that easy did you???
How you getting 600°???? Mothers oven is only gonna get up to, maybe 500° on the
cleaning cycle, and I'd hate to take the torch to those nice billet drums after all that beautiful
CNC time, soooooo......how ja do it???
When I look at the whole assembly, it gives me the feeling that I'm looking at something
new or modern, but at the same time, because of the mechanical approach to breaking,
something dated or old. Kind of a ying and yang feeling. Real cool!!!!!
I'll bet you've spent lots of late nights laying awake thinking about your designs.
Are you going to find the time to take her to Bellvue, CO for the big one this summer???
(a little wishful thinking going on there!!)

Denny Graham
Sandwich, IL

Denny, The drums just fit in the heat treating furnace at work; there was, maybe, 0.050" to spare. I didn't need to get them that hot, but I didn't take the time to make anything to guide them together, and I didn't want to find myself needing to back them out. Let's try and stay the course and all make the big ones this year.

I attached a small brass surface to each brake shoe, and now they return with a snap. The first pair is in the bonding fixture, and left alone for the night.

Looking back.....was that Mac & Cheese & Brake Shoe in the earlier picture?
I assume the brass was because the were sticking when it was just the aluminum
surface??
That clamping fixture reminds me of the hat stretcher I made a few years ago when
I couldn't find that in between sized fedora.
When my nephew closed down the family machine shop, he gave me the heat treat
oven, which needed the controller replaced. I eventually gave it back to him and ended
up making my own gas fired version.
dg

Focaccia. I found that I can both bake and work on the kart during the weekend; The kitchen counter becomes the common ground between the two activities.

You are correct about the aluminum surfaces.

Tonight, I did a lot of necessary dinkin' around with the engine in the little warm space that I have under the stairs. The goal for this evening was to establish some ignition timing marks.

I'm not sure what to call these parts; they'll help route the control rods back to the brake drums.

The brake shoes now have their pads; they'll need to be mounted to their backing plates, shimmed, and turned on the lathe; the arcs will match their drums (full surface contact).

Brake Control Levers??? That's some thick brake material, I had half that on a go cart brake I did. I use some kind of fiber glass bonded material.

---

S'all for now!

Sounds good, Vic. The shoes won't fit in drums now. Once I arc them to the diameter of the braking surface, the friction material will be a bit less than half as thick.

Today, I mocked up some brake controls with threaded rods, and tensioned the spokes on the rear wheels. I kept the rim true as I worked and checked the tension with a gauge that I borrowed from a friend. I didn't check them all, just a few to get an average( +/- 20% is acceptable). Once I measured an average of 100 Kgf, I stopped.

Don't know if you found it to be as much of a PITA as I did, but there
is no way to get the tension close on all the spokes and still maintain
the well alignment. So it sounds like you ended up the same place I
did, alignment first and as close as you can get them to the recomended
tension.
All the YouTube videos by the tool and bike manufacturers would have
you believe that you can tension all the spokes the same or within a
rather tight tolerance and still maintain the alignment. Don't kid yourself
guys.....NO WAY to do that!!!!!
Denny G

I would agree with you Denny. If Park Tools suggests that +/- 20% is acceptable, then my experience tells me that you don't have to measure all of them. You want tight wheels, but you don't want to pull the spoke nipples through the rims (weakest part in a bicycle wheel, can't speak to steel motorcycle rims).

I noodled about indoors today; braised pork, baked focaccia, tensioned the front wheels, lapped in the valve seats so that I could see the contact ring (dull grey circle in the picture), and finished a little brass clip for the spark plug.

Tonight I shimmed the brake shoes open (about 0.030" ) with sandpaper (handy), and turned the pads on the lathe until they matched the inside diameter of the drums; 250 rpm, 0.020" cuts; no problem.



Edited 1 time(s). Last edit at 2019-02-11 10:18 PM by smallboregarage.

Now...... what I really want to know is.......do you actually have one of those
leather racing helmets like in the picture?????
Denny G
Sandwich, IL

I'm often away from the kart, but never without parts of it (in a box or in my pocket). It's just another tool, really; it supplies some level of focus that I wouldn't have naturally. The last couple of days, I've been carrying around these brake actuator parts.

Such a talent......for the fourteenth time, a work of art in the making.
Now just imagine if you were putting all this effort into a 3/4 scale
Bugatti or an Alfa Romeo P3-B. It would certainly command some
big bucks over in the Buy, Sell, Trade forum that's for sure. Not to
mention the attention and trophy's it would get at any gathering of
gear heads. And you could actually run it in the apple trials at Tieton.
You gotta build real racer when you finish up on this one Chuck.
Denny G