Adjusting Sidepull Brakes

Mrs. Nerdly and I bought an old Schwinn Twinn Deluxe tandem bike and have enjoyed using it to get around town, but the front brake was questionable so I thought I’d try and get it working better.

The bike is a 1978 model, made in Chicago.

There’s no rear brake visible in the picture because it is a drum brake built into the rear hub.  When we got the bike I opened up the hub brake out of curiosity.  It looked OK and the mechanism is incredibly simple, and it worked well enough to leave alone for the time being.

The front brake is a simple sidepull style brake.  The rims are steel so the braking action is not going to be great, especially in the wet.  I started by replacing the lousy cheap brake pads with mid-range Aztec pads.  But then I couldn’t get the brake centered!

No matter how I adjusted things and lubricated the brake itself, the brake assembly would either want to rotate to the cable side or would bog and seize up.  And Sheldon Brown (R.I.P.), still my preferred source for information on bike repairs, had surprisingly little to say.

It seemed that removing friction from the works might help, so I pulled the cable from the housing and lubed it up along with the brake lever.  That did wonders for the smoothness and feel of the brake, but it still was difficult to center.  Further searching on the internet led to the suggestion of tapping the brake at the coiled part of the spring to adjust the centering.

I used a flat-head screwdriver and light taps with a hammer at the doubled area of the spring at the end of the arrow – this is attached to the center of the brake instead of one of the arms.  Sorted!  The braking action is now good (at least under dry conditions), with a nice smooth and tight feel.

Rebuilding the Rancilio Silvia steam valve

I’ve had my excellent Rancilio Silvia (“Miss Silvia”) espresso machine for seven years now and the steam wand developed a dribbling leak.   Time to rebuild that sucker!

I ordered replacement o-rings and seals from 1st line and was happy to get the parts just the day after ordering them, despite just using ground shipping.  Most of the work in rebuilding the steam valve went as described here, though there were a few things worth pointing out.

It is important to back up the flare nut fitting when removing the steam valve from the solid copper tubing connecting it to the boiler, to avoid twisting and kinking the solid tubing.  Here’s a photo with blue-handled wrenches (the top one is out of focus):

I used a couple of cone wrenches that had previously seen service in rebuilding bicycle wheel hubs (a side benefit of having too many endeavours is having a bunch of related tools that could serve other uses).

The steam wand itself was stuck hard and it took a lot of force to remove it.  It has an odd plastic bit where I expected an o-ring.  This photo shows the degraded plastic bit alongside the o-ring I replaced it with:

I removed the degraded black plastic bit when I rebuilt it.

Here is a test before I re-assembled the housing.  The PID controller I’d added years ago for temperature control is resting at the bottom left – I had to pull it out to access the steam valve.  The boiler has wooly ceramic insulation installed to try and protect the electronics in the PID

No leaks!  Hopefully Miss Silvia will provide many more years of service.

Roasting Coffee

So Mrs. Nerdly called me saying she found a hot air popcorn popper at Community Forklift for $5 – should she buy it for roasting coffee?  Why not!

Years ago I’d used a Zach and Dani’s roaster (now Nesco) when I lived in an apartment – that roaster had a nice feature of an “afterburner” to reduce the inevitable smoke from roasting coffee.  But it crapped out as the belt driving the auger started slipping, and I junked it after stripping out some parts for my junk salvage box.

This new device is a Presto Poplite model 04820 (or as it says on the bottom of mine, 0482007) and fairly powerful at 1440 Watts.  I guess there was a glass top or something at one point for popcorn, but no matter that it was missing.

I started with some green coffee beans from the fantastic Sweet Maria’s: Espresso Monkey and another espresso blend, “Espresso Workshop #21 -The Satpura Fold.”

I did four batches, two of each blend, each using about a half cup of green beans.  I put an open-ended food can on the top of the roaster as a chimney

With about half a cup of beans, I lost a few beans blown out the top, but I like to think they were mostly sickly light dried-up beans.  It did a nice job blowing the chaff out.  Definitely something to be done outside!

The end results looked nice and I look forward to tasting them tomorrow.  I got about 11 ounces by weight of roasted coffee from the four small batches.

Incidentally, I would swear I got a caffeine buzz from being near the coffee as it roasted.

GameScience dice

In a fit of nostalgia I picked up these GameScience dice, which are made in the USA and feature a “razor edge” unlike other die, supposedly providing more uniform results.


GameScience is upfront about the sprue marks left behind, but they look pretty bad on the left and center dice here.  Also, the die on the right has a pretty big smudge with a fingerprint in it – disappointing.